J Escartin
email: escartin@ipgp.frescar-tin.javier@gmail.com

Nathalie Feuillet
email: feuillet@ipgp.fr

Anne Lefriant
email: lefriant@ipgp.fr

Anne Lefriant Subsaintes'

FR Ipgp

Le Friant

Leclerc Frédérique

Andreani Muriel
email: faultrocksmuriel.andreani@univ-lyon1.fr

Dano Alexandre Microbathymetry
email: microbathymetryclaire1.marchand@orange.fr

Delorme Arthur
email: delorme@ipgp.fr

Deplus Christine

Marie-Laure Master

Gini Caroline

Gracias Nuno
email: nuno.gracias@gmail.com

Hamelin Cédric

SP U Girona

Komorowski Jean- Christophe
email: komorowski@ipgp.fr

Marchand Claire

Catherine Geology

Onstad Solveig Lie
email: solveig.onstad@gmail.com

Garcia Rafael
email: rafael.garcia@udg.edu

Mathilde Cannat
email: cannat@ipgp.fr

Geology

Saal Alberto
email: alberto_saal@brown.edu

SUBSAINTES'17 Cruise Report Coseismic ruptures & tecto-volcanic interactions at the French Antilles Arc between Les Saintes and Dominica

HAL is

Introduction

Cruise overview

The SUBSAINTES'17 cruise took place between the 2 nd and 24 th of April in an area between the islands of Les Saintes and Dominica. This area has been mapped with shipboard multibeam surveys (Bathysaintes'10 onboard N/O Pourquoi Pas? PI: N. Feuillet & C. Deplus). Les Saintes and Dominica are linked by a network of normal faults that interact with various seamounts in the area, unsampled to date and whose nature is unknown (Figure 1). This area also witnessed in 2004 a Mw6.4 seismic event along the Roseau Fault, one of the major fault structures that runs NW-SE and bounds the fault network system to the SW. This earthquake, in addition to causing damage in the nearby Les Saintes (including one casualty), also triggered a minor tsunami.

During the ODEMAR'13 cruise onboard N/O Pourquoi Pas? A preliminary, 3-day long survey, was conducted using deep-sea vehicles as a second leg of the ODEMAR cruise; F. Leclerc, who was conducting PhD research on the links between faulting and volcanism, joined this second cruise leg. During ODEMAR'13 a section of the Roseau Fault was mapped using the Remus 6000 AUV (Geomar, Germany) and the ROV Victor 6000, equipped with a multibeam system, conducted near-bottom multibeam mapping, still electronic image surveys, and 3D video surveys. These preliminary observations revealed the Roseau Fault plane, and evidence of recent fault ruptures that are most likely associated with the 2004 Les Saintes seismic event; these include fractures in the hangingwall at the base of the fault scarp, and a recently exposed fault slip plane. 3D video models were also used to estimate a vertical fault displacement of ~0.9 m associated with this seismic event. The SUBSAINTES cruise thus builds on data gathered in 2013 during the ODEMAR cruise in the area, as the fault rupture was only partially mapped and characterized over a length of ~3 km.

The main goals of the SUBSAINTES'17 cruise are A) to investigate the extent and nature of the coseismic fault rupture associated with the Mw 6.4 Les Saintes Earthquake, and quantify the displacement associated with it along the Roseau Normal fault, B) Investigate the volcanic and tectonic features in the area, sample them and observe their interactions, C) Evaluate and constrain erosion and sedimentation processes in the area and the links to active tectonics and volcanism, D) Develop video-derived 3D mapping techniques to obtain quantitative information on fault and volcanic structures (e.g., fault displacement, fine-scale geometry of lava flows, etc.)

Our AUV and ROV dives targeted the following tectonic and volcanic structures, shown in Figure 1.3 and with a geological interpretation in Figure 1.4:

-Roseau Fault, extending from the SW of the Les Saintes Plateau to the NW of the study area over >15 km -Crawen Volcano, that shows a volcanic dome within a crater and an association with faults, and located at the edge of the submerged Les Saintes Plateau -Colibri Volcano, on the southern side of the survey area, at the tip of Roseau fault, and raising >500 m over surrounding seafloor -Coche Volcano, a volcanic edifice NW of Crawen Volcano, crosscut by numerous normal faults -Agoucha Volcanoes, a series of volcanic domes located at the southern tip of the fault system, NNE of Colibri Volcano and East of the submerged Les Saintes Plateau -Roseau Volcano, a large volcanic edifice that is cross-cut by numerous faults -Souffleur Fault, a major fault cross-cutting the submerged plateau to the N of the study area, and sub-parallel to the Roseau Fault.

Each site was the target of one or more AUV dives to acquire microbathymetry, and one or more subsequent ROV dives for geological observations, image surveys, and sampling (See AUV and ROV operations sections below).

The scientific team onboard included members from French Institutions (IPGP, Géo-Azur/Université de Nice, IFREMER, U. Lyon, ENSTA), and international ones (U. Girona, U. Bergen), and covering the expertise on tectonics, volcanology, marine geology and geophysics, and computer vision and robotics. A personnel exchange was conducted half-cruise (13 th of April).

AUV/ROV mapping, survey, and sampling strategy

The original proposal included solely ROV VICTOR to conduct both mapping and sampling, but the AUV AsterX was subsequently included. As the AUV flies more than 6 times faster than the ROV (up to 3 kt vs. .5 kt or less for the AUV and ROV respectively during multibeam surveys), and to optimize both mapping and sampling in the SUBSAINTES area, we carried out geophysical surveys (microbathymetry and associated measurements such water column measurements) mainly with AUV AsterX. ROV 6000 was equipped with the sampling module ("Module Prélèvement"). We exchanged the vertical, down-looking video camera by the new OTUSII electronic still camera, to allow the acquisition of digital images for seafloor photomosaics (at a nominal height of 5 m above seafloor). ROV Victor conducted thus rock and sediment sampling, geological observations, and camera surveys (OTUSII and video). Figure 1.5 shows the AUV and ROV tracks together with VIC-TOR sample locations.

AUV AsterX and ROV VICTOR were deployed in alternance, with a dive cycle of either 24h (~12h for AUV and ROV operations per day) or 48h (~12h for AUV operations and ~36h for ROV operations -see calendar in Section 1.4).

AUV operations were conducted primarily in daytime, with a target launch in the early morning, and a recovery in the early evening. L'Atalante followed the AUV during surveys, for relocation of the vehicle, and control of the operation, vehicle status, and checks on data acquisition. AsterX conducted a total of 13 dives (#394 through #406), with a single dive aborted and one shortened. AUV dives logged around 500 km with ~100h of bottom time. We acquired bathymetry at a resolution of ~1 m per pixel over an area of ~100 km 2 .

ROV VICTOR was operated on a nightly dive cycle during short dives (~12h cycle), or over two nights and one day in between (36h cycle). As sampling is one of the main goals of ROV dives, longer dives included NASA elevators to bring samples back to the surface, replacing full sample baskets by empty ones. This allowed for continuous sampling through dives, regardless their length, with minimal time loss at the seafloor. For this cruise, the Module Prelevement was used throughout, but the vertical OTUS camera replaced the vertical video camera to allow us to acquire imagery for photomosaicing. The Module Route was not used during the cruise.

We conducted a total of 13 dives (#653 through #666), logging more than 160 km along the seafloor over ~ 260h of bottom time, corresponding to almost 11 days (more than half of the cruise duration). During these dives we acquired more than 190 rock samples, 4 sediment cores, >100.000 OTUS camera images, in addition to HD video imagery (two video channels were recorded continuously, including in all cases the main science camera Camera Principale).

Cruise data

A complete dataset of the cruise has been backed up both at IPGP and GéoAzur/Université de Nice, including videos, geophysical data, and working files (sample tables, maps, etc.) generated onboard. A subset of the cruise data and working files, as reported in this Cruise Report, is provided as ancillary data. Full listing of files is provided in file 'DataFles_Listing.txt' within the Data Annex folder.

Both the scanned Cruise Logbook:

SUBAINTES2017_Logbook_Cruise.pdf

And the Rock Logbook:

2_Logbook_Rocks.pdf are included in the Data Files (folder Logbook), associated with this cruise report, and included as an annex of this report.

Excel tables with the sample information (sample sheets, packed boxes/bags, sample distribution) are included in the Data Files (folder Samples).

Full list of IPGP and GeoAzur back up (all video, cruise data, onboard working files) are listed in the folder Subsaintes_Backup.

Other files and folders with relevant data are described in the pages below.

In the following sections of this report we provide information on the ROV and AUV dives, summaries of samples, and other instruments and operations (pressure sensor, Eh sensor, nephelometer, Kullenberg corer).

Calendar of operations

The summary of operations as a calendar is provided below, in the folder '17_ReportTables' of the Data Annex, available as Subsaintes_Calendar.xls.

During the SubSaintes cruise from departure to return to dock, ~61.5% of the ship time was dedicated to ROV operations, 24% to AUV operations, 8% to transits, 3% to other operations, and 3.5% corresponded to downtime -this represents 87% of ship time dedicated to scientific experiments.

AUV AsterX operations

Introduction

The Autonomous Underwater Vehicle (AUV) ASTERX from IFREMER (Figure 3.1), is ~4.5 m long, weights ~800kg on air and can be operated in water depths up to ~2700 m. The system comprises the AUV itself and the Calisto launch and recovery system, deployed with the A-frame of the ship, and that allows AUV deployment and docking in the water. The navigation system uses an inertial system Phins-Ixea and a Loch-Doppler WH300-RDI. The AUV is also equipped in standard configuration with a Seabird CTD SBE49/19. A turbidy sensor, supplied by INSU Instrument Pool, and an Eh sensor, sensor kindly supplied Prof. by K. Nakamura, for water column measurements; these are described in following sections of this report. Microbathymetry was acquired with a Kongsberg Reson SMF EM2040 multibeam system. Calisto, with AsterX docked inside, is lowered into the water with the ship's A frame, and the AsterX is then released to proceed with pre-dive checks before starting its mission. At the end of the dive Calisto is lowered into the water, and AsterX is driven on the surface to dock into the recovery system. AsterX is then hoisted onboard, docked inside Calisto.

During missions, the AUV is tracked with a USBL system to relocate the vehicle when needed, to redirect it in case of problems on the mission follow-up, or to terminate the dive.

Post-cruise (May 2017) the AUV was renavigated. Details are given below in subsection 2.7 AUV Renavigation.

AUV AsterX surveys

During SUBSAINTES'17 cruise 13 missions were flown by AsterX for microbathymetric surveys. One dive was aborted and provided no data, and a second dive was interrupted shortly after the start of the mission (see Table 1). Missions at the start of the cruise (dives #394 through #400) were flown tracking the bottom at ~70 m above seafloor. Owing to problems with the bathymetric data (noise and artifacts), a second mode of flying was implemented in the second part of the cruise, with constant inmersion instead of bottom tracking (dives #401 through #406). The summary of multibeam bathymetry dives are presented in Table 3.1 below, and the areas covered by the AsterX multibeam mapping are shown in Figure 3.3. Additionnal details (times of dive, on bottom, etc.) are given in a table in the Annex. 3.1).

AUV AsterX mission summaries

Dive technical reports are available in the Data directory '3_AUV_TechnicalReports'. Renavigated Y/N ? Yes (see navigation map below) -at the time of writing the report (end of cruise):

AUV

Comments : data shows important artefacts, probably due to non-filtered immersion data. One swerve event, at the end of the survey.

Produced bathymetric grids (mnt and grd):

PL394_mnt_1m_postnav_Ssc.mnt PL394_mnt_1m_postnav_Ssc.grd

Grids are corrected from tide, rolling, renavigated, and manually cleaned.

Produced back-scatter mosaics :

MOSComp_NAVR_AUV-PL394-03-01_1m.grd

This back-scatter mosaic was produced with Sonarscope. A statistic compensation was applied from the curve processed over file 1 which seems to be the most flat and homogene about back-scatter for this dive. Mosaic gridded at 1m, using navigation calculated with Delphins software by Ifremer.

Water-column comments : Polar echograms and echo-integration, a specific method developed by Ifremer, has been produced to help to spot flares in the water column.

No signal was found in profiles passing above volcanic dome. Produced back-scatter mosaics : Mos_Comp_SsTraversiers_AUV_PL395-04-02.grd However, it's better to use the data of dive 400 as we had trouble on dive 395 with bathymetry and attitudes. This back-scatter mosaic was produced with Sonarscope.

A statistic compensation was applied from the curve processed with file 24 which seems to be the most flat and homogene about back-scatter for this dive. Mosaic gridded at 0.75 m, using new navigation calculated by Ifremer.

Water-column comments : Polar echograms and echo-integration has been produced. No flares signal in the water column, only fishes or relief noise coming from the MBES emission secondary lobes. Comments : data shows much less artefacts than for the two previous dives, the level arm value was corrected before the dive.

Produced bathymetric grids (mnt and grd): PL396_mnt_1m_postnav_Ssc.mnt PL396_mnt_1m_postnav_Ssc.grd

Grids are corrected from tide, rolling, renavigated, and manually cleaned.

Produced back-scatter mosaics: MosaicPostNavCompFile15-AUV-PL396_Files1to23_0,75m_.grd 75m.grd This back-scatter mosaic was produced with Sonarscope. For this dive, bathymetry DTM back-scatter mosaic is splitted in 2 parts to avoid flaws in the processing, as well as "crosses" that prevent a good interpretation. File 24 doesn't appear as it was bad (307 Ko size and no records inside).

For profiles 1 to 23, a statistic compensation was applied from the curve processed over file 15, while for the profiles 24 to 40, the curve was calculated over file 36. Mosaic gridded at 0.75 m, using new navigation calculated by Ifremer.

Water-column comments : Polar echograms and echo-integration has been produced.

No signal in the water column. Dive cancelled due to damage on communication system to the multibeam echosounder. Fixed in a day. Grids are corrected from tide, rolling, renavigated, and manually cleaned.

Produced back-scatter mosaics :

MosaicPostNavComp_AUV-PL-400_AvecTraversiers_0,75m.grd 75m_interp.grd This back-scatter mosaic was produced with Sonarscope. A statistic compensation was applied from the curve processed over file 10. Mosaic gridded at 0.75 m, using new navigation calculated by Ifremer. The bathymetry suffers flaws coming from pitch but back-scatter has a good quality for this dive.

Water-column comments : Polar echograms and echo-integration has been produced. Nothing to see. Geometry : Acquisition test profiles: auto-immersion vs. auto-altitude. 6 profiles along the northern tip of the Canyon segment, along the Roseau fault. Then several NW-SE profiles west of Les Saintes plateau, acquired in auto-immersion mode.

Renavigated Y/N ? Yes.

General Comments : New acquisition strategy: auto-immersion mode. ABORTED after the acquisition test and of 4 out of 6 profiles along the northern tip of the Canyon segment (though AUV traveled along the last 2 without acquiring data). Data recovered from the MBES processing unit's hard drive. Tests profiles (files 1 to 4) has been saved and studied.

Grid offset = 100 m

Grids are corrected from tide, and manually cleaned. It appeared since the beginning of the auto-immersion mode (Dive 401), that post-processed navigation data bring along artefacts never seen before the 401 Dive. That is why maps are gridded with raw navigation. Data are of a good quality but not well positioned. For this area, two complementary sets of data were gridded with profiles 8, 9, 10 and 32 to 37. The reason of that is because of the overlapping of profiles that mask structures under those.

Produced back-scatter mosaics : MosaicRaw_All_Prenav_AUV_PL402_SansTraversiers_0,75m.grd MosaicRaw_Prenav_AUV_PL402_AvecTraversiers_0,75m.grd This back-scatter mosaic was produced with Sonarscope. A statistic compensation was applied from the curve processed over file 3. Mosaic gridded at 0.75 m, using raw navigation.

Water-column comments : Polar echograms and echo-integration has been produced. Nothing to see. Geometry : Eleven N-S profiles along the faults.

Renavigated Y/N ? No General Comments : Acquisition was configurated in auto-immersion depth when the profiles were parallel to the isobaths, and in auto-altitude mode otherwise.

Produced bathymetric grids (mnt and grd): PL406_mnt_1m_super_brut.mnt PL406_mnt_1m_super_brut.grd Grids are corrected from tide, and manually cleaned. We used raw navigation. Warning, one of the profile have been shifted during acquisition. We might see twice the structure. The profile shifted from auto-altitude to auto-immersion and the AUV starting to fly up quickly. During this configuration, the loch lost the ground position and as the result, the navigation is bad for this particular profile.

Produced back-scatter mosaics : Mosaic_Prenav_AUV-PL406_SansTraversiers_0,75m_interp_flipud.grd This back-scatter mosaic was produced with Sonarscope. Raw mosaic gridded at 0.75 m, using raw navigation. Corrected navigation is not available yet as it is week-end.

No homogeneous file from the back-scatter point of view is available for this dive.

Only the raw mosaic is processed.

Water-column comments : Polar echograms and echo-integration mosaic have been produced.

AUV AsterX microbathymetry & acoustic backscatter

The 13 missions flown covered a total of 100 km 2 ; the location of each dive is given in the previous section (Mission Summary Reports), in Figure 2.3, and in Table 2.1.

After recovery of the vehicle the bathymetric data was downloaded and roughly cleaned in Caraibes to generate maps allowing data quality control, and obtaining maps that could be used for ROV planning and navigation. Navigation data was sent back to Toulon for processing onshore, and to obtain a vehicle renavigation that in principle should provide better quality data.

The first dives displayed significant noise that could not be corrected using the renavigated data. To determine if the bathymetry was noise due to AUV navigation, during dive #401 we conducted profiles of over an area to compare the differences in the data quality a) going up or down slope, and b) using bottom tracking to fly at constant altitude, or programming a vehicle immersion. These tests are presented in section 2.4.1. The vehicle presents significant oscillations in heading and pitch, with a lesser impact in roll, as shown in section 2.4.2.

Grids obtained onboard for each dive are shown in section 2.4.3, and the corresponding grids are in the Data folder '4_AUVGrids', together with the microbathymetric maps for each dive (postscript files). The file names indicate if the grids have been generated using the raw or processed navigation data (prenav and postnav respectively). All cleaning and editing has been conducted with Caraibes. Some of the grids have been createdusing the Sonarscope software (indicated as Ssc in the filename); otherwise gridding was done with Caraibes.

Final maps will be available in a few months after detailed point editing is finished.

Bottom track vs. immersion navigation: Tests dive #401, EM2040 data

Tests on AUV navigation are analyzed on tracks conducted during dive #401 (Figure 2.28).. Files 1 and 2 correspond to bottom tracking altitude, and Files 3 and 4 to immersion navigation. Files 1 and 3 are acquired during a descent, while 2 and 4 during ascent of the same area (Figures 2.29,2.30). The comparison of Files 3 and 4 for a dive with immersion prescribed, the similarity is significant. The two steps corresponding to depth changes in vehicle immersion are associated with extreme pitch values of -38° and +40° for descent (File 3) and ascent (File 4, Figure 2.32) It is also clear that the pitch during the rest of the survey shows an oscilation of ±5°, that is of lesser amplitude and more regular than for the survey navigated with altitude tracking (Figure 2.31). Vehicle attitude shows important peaks in pitch, of -34° (descent) and a return to ~0° within 30 s. We also observe a regular oscillation of ±5° in the heading (Figure 2.35). From the results of this test survey, we decided to combine both flight modes in the following dives to benefit from their different advantages. Auto-altitude mode was used over highly changing bathymetric areas in order to prevent pitch jumps observed in auto-immersion mode. Auto-immersion mode was used over smoother reliefs as it is more stable and to prevent pitch oscillations observed in auto-altitude mode.

AUV oscilations along slopes: Files 14 & 24, #394

Dives using bottom tracking to keep a constant altitude show that the vehicle oscillates in along slopes. These oscillations initiate not at the beginning of slopes, but ~10 minutes later, as seen in File 14 of Dive #394 (x=~800 in Figure 2.36, see pitch), resulting in artifacts in the bathymetry that are not properly corrected using the vehicle's attitude (green track in Figure 2.37). The period of this oscillation is ~25 s. These oscillations are seen on the heading and pitch, and on the roll to a lesser degree. File 24 shows the behavior of the vehicle during an ascent. Oscillations do occur also during ascent, and after a damping at the summit of this track, they initiate during the descent (in this case, the Crawen volcanic dome). In this case, heave is uncorrelated with other vehicle oscillations. Pitch show oscillations with a period of 25s during ascent, that shorten to 12 s during descent (Figure 2.38). File 24 corresponds to the green track in Figure 2.39.

AUV EM2040 backscatter

Back-scatter mosaics were produced during the SUBSAINTES cruise in order to help determining the sampling targets for the ROV dives.

The back-scatter mosaic has been provided in .grd format for further conversion in MIMOSA dive planning software, used for both AUV and ROV.

Back-scatter final mosaics in GMT grid format are available in the Data directory:

Additionnal grids and files associated with the backscatter, and including these grd files, ara available in the Cruise's working directory:

/science/SUBSAINTES/MNT-OK/ ExportsPourGMT-KMZ-SonarScope
Back-scatter processing is to be found in:

/science/SUBSAINTES/REJEU/Sonarscope
Nature of back-scatter data Instead of being based on sound speed in the sea and time, back-scatter is based on the received signal's relative amplitude. The georeferenced mosaic is in decibels (dB), over a gray scale.

Back scatter data is read in the .all files from the MBES EM2040 where it is recorded in real time.

Processing of back-scatter data

Navigation of AUV:

Processing on back-scatter data is systematically done once data are available. Navigation of the AUV, coming from the MBES, is not accurate and can show derivation with time. INS VS post-processed navigation is calculated with Delphins software in Ifremer, Toulon, with a delay of one to 3 days. Therefore, a first Mosaic with the navigation not corrected is calculated, and names of the files contain: "pre-nav".

From dive 394 to dive 400, post-processed navigation calculated with Delphins software in Ifremer, Toulon, was imported in order to georeference correctly mosaics. Names of files contain "post-nav". After the dive 400, we pin-pointed that the noise seen in the bathymetric data were coming from a bad incorporation of the immersion and the attitude data into the MBES. From dive 401 to dive 406, when the AUV dived in "auto-immersion" mode, the post-processed navigation files contain also recalculated attitude data. Attitude data for previous navigation files were provided afterwards. This new format is not supported by Sonarscope yet. However, after analysis with Sonarscope, the AUV recorded but also the corrected immersions seem not to be plenty reliable and make flaws in the bathymetry.

This will have to be deeply studied after the cruise to try to get to the high-quality data that echo-sounder is able to provide.

Choice of mosaic horizontal resolution:

Sonarscope allows exporting data tables, calculating statistics on the data, and for instance, calculating the distance between two pings (Figure 2.53). Histograms of this inter-ping distance are obtrained for each dive, and allow choosing the best pixel size for mosaic calculation. In general, a horizontal resolution of 0.75 m is chosen for both the back-scatter and the DTM using a specific Sonarscope tool, to generate the mosaics onboard (Figure 2.54).

Compensation

Examination of the raw mosaic is needed to select a sonar file with the most homogeneous back-scatter characteristics. This file is then used to process the compensation curve, that is subsequently applied to all the dive profiles/files that have the same emission mode

Then, the mosaic is processed again but answering yes to the question about compensation when building the mosaic as requested by Sonarscope (Figure 2.56). The previously saved compensation curve is chosen and the mosaic is built applying it over all the chosen files.

The compensation process is statistical and calculated over 1 file. Therefore, it has limitations, especially over steep areas as the file for compensation is systematically chosen over flat and homogeneous areas.

Eh Sensor

An Eh sensor, provided by Prof. K. Nakamura, was installed in the AUV (Figure 2.58). This sensor is widely used in the exploration and search of hydrothermal plumes and associated vent fields. The purpose of including this instrument in the AUV was two fold. First, we tested the possibility of including this sensor as part of the standard suite of sensors in deep-sea vehicles run by IFREMER, and include the sensor data in the AUV's data streams. This first objective was fully accomplished. Second, Eh anomalies in the water column, if any, may indicate the presence of hydrothermal fields in the area, unknown to date. None were found.

The Eh sensor is an electrochemical device that compares the voltage difference between an electrode made of inert metal (platinum), which is in contact with the seawater environment, and a silver/silver chloride electrode, which is placed in a silver chloride solution, and acts as a standard. The Eh sensor responds to all ions and indicates how chemically reactive a fluid might be. Hydrothermal waters contain chemicals, like hydrogen sulfide, that make the Eh decrease in value. When the vehicle moves through the plume of a vent, the pH does not change significantly, but there can be a dramatic shift in the Eh level. The magnitude of the Eh anomaly is also inversely correlated to the distance from the source, which can be exploited to identify the the vent source.

For each dive, data were acquired and stored in the AUV's rdm data stream as : 110.10 $NAV, 090417,153524.000,1545.88891,N,06128.72069,W,0555.63,336. 756,-3.48,+0.52 corresponding to: Electric resistivity $NAV, day month year, hour minute second, longitude(degree decimal minute), North, latitude(degree decimal minute), West, depth, heading, pitch, roll

The .rdm files for each dive were converted into a single .csv file using a Matlab script written by Aurélien Arnaubec and Caroline Gini to facilitate processing. Figures were produced with Matlab using the .csv files for each dive. For each dive, the data of the descent and ascent to and from the seafloor were deleted based on the depth profile of the dive to remove water column data (ascent and descent of AUV).

CSV files and plots (png images) of Eh data for each dive are available in the '6_AUV_Eh' folder of the datafile. All Eh data and scripts are available in the folder from the cruise's WORK directory : 'science/REJEU/AUV_brut/EH-SENSOR'

Nephelometer

A Seapoint turbidimeter sensor with an RBR Virtuoso data logger, borrowed from the Instrumental Pool of INSU (CNRS). Programming of recording and recovery of data is done through the Ruskin program. The instrument was installed within the rear part of the AUV, with the Seapoint sensor exposed to the exterior at the bottom of the vehicle.

The turbidity record has a sampling interval of 3 seconds, continuously recording from the start:

2017-04-08 22:02:54.000

to the end of AsterX dive #406:

2017-04-23 00:00:09.000

We identified no anomalies in the water column near-bottom during the AUV surveys.

Two This folder contains a) a pdf file, 17_127_CR_SUBSAINTES_AUV.pdf, with the information on the reprocessing carried out by GENAVIR, and a pdf file with information following a meeting between GENAVIR and Science Team members on vehicle navigation, '17_155_CRreunion_posttraitement_SUBSAINTES.pdf'.

ROV VICTOR 6000 operations

Introduction

The ROV VICTOR 6000 (IFREMER) was deployed with the 'Module Prélèvement' during all SUBSAINTES dives. We modified the ROV's camera configuration to swap the vertical video camera by the OTUS II electronic still camera. This swap was intended to provide flexibility during geological exploration and sampling dives so as to conduct small-area mosaics. OTUS II, with the LED panels installed in VICTOR with Module Prélèvement, can acquire images at ~5 m altitude, instead of the ~10 m planned for surveys using the Module Route, that includes more powerful lights. OTUSII was used both to perform photomosaics in selected areas, and to document seafloor nature during transits. We acquired more than 100.000 OTUSII images.

Overview of ROV VICTOR dives

We conducted a total of 14 VICTOR dives (#653 through #666), with none aborted. Technical ROV dive reports are available in the Data folder '08_ROV_Reports'. Other cruise ROV files are available in Data Folder '09_ROV_Navigation', including:

-Text files with longitude, latitude, depth (vicXXX.txt) -Adelie extractions of navigation (nav_estimeXXX.dtxyz) -Events names and location information (ptrXXX.dtxyzname)

This folder also includes the files combining data for all dives, both in matlab format, 'subsaintes2017_estime.mat', and as ascii csv file, 'subsaintes_estime.txt', with the following format: All dive data are available in the ROV data folders (Videos, OTUSII, data streams, etc), in addition to extracted and processed data, at: 'science/WORK/ROV_VICTOR' folder.

The fourteen ROV dives where conducted on a 12, 24, or 36 h cycle (see Table 3.1 and Calendar above). Issues with the recording system resulted in loss of video data during dive #661 on Colibri volcano, and loss of naming of video files in several dives. Blackouts during dives, at times frequent and closely spaced, resulted in time loss that did not impact the operations nor the achievement of objectives. The total bottom time was ~258h, with a total of ~161 km of track length (see Table 3.1). During these dives we sampled 201 rocks (see section 4 below), acquired 4 sediment cores, performed numerous video surveys for 3D reconstruction, and OTUSII surveys. The bottom time corresponds to slightly more than 50% of the time spent on site. The average speed, including sampling, black outs, video acquisitions, etc, is slightly superior to 0.6 km/h (see Table 3.1 and Figure 3.1).

Individual dive Summaries are given in section 3.5 below, while sample operations and descriptions are given in the Section 4.

ROV IMAGERY

Optical imagery was acquired using the camera systems mounted on the ROV. The OTUS2 was assembled down-looking on the ROV's sampling module and is mainly intended for high resolution still imaging and 2D mapping of the seafloor. The camera setup consists of a Nikon DSLR camera that can be controlled remotely from the vehicle console through a browser interface. The main specifications of this camera are the following: The HD camera is the pilot's main observation camera and is mounted on a pan-andtilt platform. It's a sony FCB-H11 camera with corrective optics and dome port. It was used mainly for image acquisition for 3D reconstruction. The ability to dynamically change the pose of the HD camera (using pan/tilt) enabled us to adjust the acquisition setup to the observed scene and obtain slanted views critically required in the 3D acquisition process.

Camera calibration

The accuracy of the final results (either 2D mosaics or 3D models) depends strongly on the knowledge of a projection model that describes the image formation inside the camera. To obtain the parameters of this model both cameras were been precalibrated using MATLAB's calibration toolbox (1). The following intrinsic parameters, with uncertainty bounds of three times the standard deviation were used for all onboard processing: The HD camera can change its focal length to zoom in a specific area of the scene. However, the calibration was performed with the widest angle setting (e.g. the minimum focal length). As such all image acquisitions were executed at the same wide angle setting.

Intrinsic parameters of OTUS2

Navigation data

For the 3D acquisition, the ROV navigation data was obtained by the real-time navigation. This navigation is obtained with a IXblue PHINS III system which merges in real time USBL data, inertial data and DVL data. It will be possible to post-process navigation to obtain more accuracy and correct for DVL bad configuration present on two dives. The global accuracy of this navigation is around 1m and has no drift because of USBL registering.

In May-June 2017 a new renavigation dataset was provided (see above). Some of the models presented below will be re-calculated using this dataset. This post-cruise processing is on-going and will not be included in this cruise report. Final models will be provided at a later time, when available. The lever-arm of the HD camera is (-216.00,149.50,642.00) mm. This corresponds to the position of the camera described in the ROV position frame.

Navigation data associated with the OTUS frames are retrieved automatically by the camera software that has access to the ROV realtime navigation datagrams. During an Otus survey a navigation file with extension .dim2 is created. This text file can be read from inside Matlab with a simple command to access the following fields: Navigation data associated with the HD camera was retrieved indirectly by interpolating the values of the real-time navigation files to obtain estimates of navigation at the instants of the frames extracted from the mp4 files.

Acquisition protocol

The main strategy for the 3D optical surveys was to have the ROV camera looking fronto-parallel to the vertical walls, and to move the vehicle slowly sideways (at 0.2 to 0.3 m/s) while keeping a constant distance of 2-3 meters from the walls. Perform 2-3 or more transects if needed at different altitudes and with some overlap among transects. HD camera could be tilted down (although avoiding imaging the ROV basket). In areas with narrow canyons ("fissures") the ROV should fly above it with the camera tilted (avoiding capturing the horizon). It is preferred to perform the survey in opposite directions to capture the geometry of the scene from both sides.

For the 2D optical mapping, the intended reference altitude of the ROV was 5m with the speed of 0.2m/s. A desired overlap of 35% between the tracks is obtained with 3m distance between the transects. However, due to the rugosity of the terrain and piloting constraints, this geometry was extremely difficult to keep.

For the majority of sites, multiple distance measurements were taken using a laser caliper. The caliper consists of 4 independent laser point projectors, from which 3 were mechanically well aligned to project parallel laser rays. When projected on a flat surface perpendicular to the laser rays, the point projections form a square with sides of 16.5 cm (for the two sides created by the 3 well aligned lasers). These distance measurements serve to validation of the accuracy of the scale of the models. Furthermore, these measurements can potentially be added as additional observation to the reconstruction software in the future, to further improve the scale accuracy of the models. Information on the laser measurements is given in section 3.3.6 below.

2D optical surveys

The OTUS2 camera was used throughout the cruise for the acquisition of downlooking high resolution still images. The table below contains the list of the most relevant acquisition sessions. Most of the acquisition was done while the ROV was navigating between sites, and therefore comprising sparse and non-overlapping transects. In table 3.2, the entries marked in bold correspond to acquisition sessions specifically for the creation of 2D area mosaics, thus executed under a prescribed survey pattern of higher transect overlap.

Table 3.3 below contains all OTUS2 acquisition sessions with more than 20 images. For some of the surveys, the OTUS2 camera was turned on and off for each transect, thus resulting in a large number of acquisition sessions. Data from the last dive of the cruise (dive_666) were not available at the time of writing this report, and therefore is not included.

3D optical surveys

During ROV dives several video sequences were acquired for 3D reconstruction, primarily of outcrops (striated surfaces, exposed cross sections of detachment fault zones). These video sequences are listed in Table 3.4. A review of models is being conducted post-cruise, and the final set of 3D reconstructions is not available at the time of writing this report. 198,199,200)

Preliminary results of 3D model construction

The 3D reconstruction pipeline used for processing the data consists of modified open-source solutions for the following processing steps

Preprocessing -Comprised white balancing and contrast stretching. For these a simple method for the estimation of the color of the illuminant was used. For most of the models, the contrast was stretched using an histogram specification technique. For the cases where the illuminations was highly non-homogeneous (such as when the scene was very slanted ) a CLAHE method was used.

Structure from motion -Using the acquired images and navigation data of the ROV a sparse representation of the observed scene together with the pose of the cameras is estimated. Two different approaches were used to process the data. Models with "_AA" postfix used only imagery data (feature points) in the bundle adjustment process while in models with "_KI" navigation data was also included in the minimization. To obtain properly scaled and geo-referenced "_AA" models, additional step of applying a similarity transformation is required. The transformation is computed by minimizing the difference between the trajectories from the reconstruction and navigation. A slightly adjusted version of openMVG3 was used.

Densification -Using initial pose estimation for each camera and a set of sparse 3D points, a denser point cloud representation of the model is computed by trying to estimate the depth of each pixel in every image. Result is denser point cloud, consequently enabling the higher detail representation of the observed scene. An opensource library openMVS4 was used.

Surface reconstruction -Using dense point cloud as in input, triangle mesh is computed by estimating the best fitting surface to the data. As the selected method for surface reconstruction 5 provided in openMVS produces a triangle mesh with a large number of triangles, a simplification step was also used to reduce the number of tri-angle faces. The simplification tries to minimize the number of triangles by combining adjacent triangles without changing the topography of the scene.

Texture mapping -The resulting simplified triangle mesh is used together with the set of input images to produce a final textured object. Using known camera poses (estimated in the SfM process) texture is mapped on the reconstructed surface and combined by minimizing the visual differences at seams between patches used from different images. To obtain a globally consistent texture global seam leveling option was used. The process is available in MVS-Texturing6 library.

During the cruise, 28 models were constructed, scaled and geo-referenced (see table 3.4). All models were saved in OBJ format and are available together with sample screenshots with the Data associated with this report. As an example, Figure 3.4 shows the 150m long and 30m high model reconstructed from the optical data acquired in ROV dives 654 and 658, with a detail shown in Figure 3.5. In order to obtain an initial estimate of the accuracy of the model, laser measurements performed during the acquisition (Figure 3.6 right) were used for comparison to the measurements obtained from the model (Figure 3.6 left). The process was done by hand and is error-prone, so further automated process will be conducted post-cruise.

Table 3.5 shows views of the different models constructed onboard for reference. The map of laser measurements is shown in Figure 3.7, based on positions reported in the file LASER_final.txt.

Video acquisition, problems, & file renaming

During all ROV operation dives, two video streams were recorded as multiple MP4 files. The first stream corresponds to the ROV pilot HD camera (also used for the 3D reconstruction). The HD video was recorded to disk without text overlay (also referred to as incrustations). The text overlay is saved on a separate file with extension .ssa and can be seen while playing the video using a video player such as Videolan's VLC. The overlay contains some navigation data, such as the depth and heading, and current time. The video of the HD camera was compressed into smaller MP4 files preserving the resolution, but lowering the quality, and intended for distribution among the scientific team. This video was recompressed using FFMPEG and a bit rate of 6 Mbit/sec.

The second stream corresponded to one of the remaining ROV auxiliary cameras, which was selected by the scientist in charge during the mission. The video was recorded in standard PAL video resolution and saved in MP4 file format.

During the ROV dives we suffered blackouts that implied rebooting of the ROV computer systems. These interruptions had two consequences. First, some of the videos, particularly those re-started by the ROV pilots, had a file naming inconsistent with the video archival system, and lacked incrustation files. Furthermore, during dive #661 (Colibri volcano), there are no video recordings for the first part of the dive, starting on 20170414 at 09:32; normal video recording was initiated at 15:08. This video loss is also associated with a lack of electronic logs. Hence for dive 661 the only records we have for the first hours of the dive are the manually kept logs. Videos with inappropriate naming concern dives # 655 (1), 659 (6), 661 (5), 662 (25), 663 (84) and 664 (15); some of these videos where recorded on-deck, as part of the VICTOR preparation for the dive. These videos names differ from the standard, and have filenames as, e.g.,:

Encoder1-[2017-04-18_03-49-46]-000.mp4 Instead of: Subsaintes_Subsaintes11_170418034946_XX.mp4

The subtitle files of the 'Encoder' files are absent. In some instances, the videos were recorded with hard incrustations, while in others the only time/date reference is that of the filename. However, it appears that date/time from the filename can be shifted from minutes to days.

We have listed in a Excel of all the videos concerned, and explored the filenames and incrustations to evaluate which files had proper date/time naming, and which ones required a renaming to match the actual UTC date/time. This excel table, Vid-eo_renaming.xlsx, is available in the associated data folder: 10_ROV_VideoProblems

We identified the 'uninteresting' videos that correspond primarily to the water column, deck (no seafloor imagery). Another set of videos has been defined as 'interesting' in this table, and those require a re-evaluation post cruise.

A third group of videos identified as 'interesting', correspond to longer video files with seafloor imagery, that are thus processed to obtain adequate renaming. A subset of these 'interesting' files do have hard incrustations that appear to be showing the correct UTC time. A second subset does not have incrustations.

Our evaluation suggests that the filename shows the accurate UTC start date and time in some instances, while in others there is a shift (lag) of 30, 50, or 90 minutes relative to the real UTC acquisition date/time. There also seems to be a relation between the time shift (0, 30, 60 or 90) and the number at the end of the filename (000, 001, 002, 003).

Some of these files can also be checked against the ties at the end of the previous file, or the beginning of the following one from the same camera or the other video channel. In cases where there is no video before or after, and the other camera channel did not record, this comparison of times cannot be achieved. Finally, a group of files do have incrustations that are accurate in UTC time, but have a filename that is not correct. We verified that, for most cases, the date of file modification (rather than the date/time given by the filename), can be exploited to assign the right filename.

For good number of videos, particularly the larger ones (both in size and duration), we are confident that we have been able to determine if there is a shift or not in UTC date/time, and its magnitude. For those, we wrote a python script to:

-Rename the 'Encoder' files to have consistency with the rest of standard video files -Generate a subtitle file that contains the accurate UTC time, and when available the heading and immersion, sampled every secong from the NMEA ROV files

The script soustitres.py is available under the folder: 10_ROV_VideoProblems/processing This script takes as an input a) a CSV file with the original file names and the time shift calculated after the video evaluation described above, and b) the attitude camera file extracted with ADELIE. The output is the renamed video with the associated subtitles.

To track these modified files, the name contains two parts:

The 'standard' filename with the UTC time, and appended to it, '_OLD_' followed by the original filename. We also maintained the original files with the corresponding filenames.

The output is the renamed video with his subtitles. The name is in two parts: first the new « normal » name, then _OLD-and the old name. We also kept the original files, so there is two versions of these videos in the video directory of the dives: one with the old name, one renamed. The Excel table Video_renaming.xlsx contains 3 sheets: a list of the concerned files, a list of the already processed files and the processing_input table (exported as a CSV for processing). Unprocessed files will require a post-cruise review and renaming, as determining the accurate UTC date/time needs to be evaluated in a case by case basis, and this determination is likely less straightforward that that of the videos processed onboard.

The video duration, required to generate the incrustations, is extracted with the command ffprobe from the ffmpeg program. Programs, tables and input files, together with the script, are available at 10_ROV_VideoProblems/processing. conglomerate, creating a notch due to erosion. Stratas are dipping to the NE but are often broken and deposited on the SW dipping sediment slope. 06:42 AUTT7, SBS-665-194, sampling the micro-conglomerate. 06:53 Passing across the basin parallel to the fault, along the antithetic fault. Strata dipping to the SW, cracks and concretions inside, around SF9. 07:32 SF10, back to the base of the fault. Ridges on the bathymetry are small fault scarp, highly degraded, with black concretions that fill cracks, and that cover the fault scarp itself. Sampling the concretion: SBS-665-195. 07:59 heading SW a little bit to pass 2 of the scarp, small fault plane (laser) visible.

Dive summaries

On the hanging-wall, a straight gully in the sediment looking artificial (manmade? Drag?), and several concretions that are linear, N133ºE striking, with perpendicular smaller branches. 08:15 Starting a profile perpendicular to the scarp (to SF12). Plurimetric blocks (>10m) at the base of the scarp. Some present centimetric stratas that are black or green, these stratas intrude each other, with "plume" like pattern. Fluidescape structures? 08:17 SBS-665-196 is a piece of this material, taken in a black layer, in a fallen block. 08:42: Going up. Scarp is covered by plurimetric slabs of indurated sediments. One is gently tilted, and the structural surface is dipping to the SW, not sedimented, it shows dense network of fractures and fissures. 08:53 3D video of this structural surface that looks like small-scale damage, till 08:56. 09:00 At the base of the second slope break. not a tectonic scarp but edge of stratas, highly degraded. Rock is granular with lava clasts. On top of this >5m thick strata, we find the black/green deposit. 09:23 Heading toward the 3 rd and topmost scarp. Fracture N170. 09:33 Approaching the uppermost scarp, soft slope with sediments and rocks (talus).

The scarp is vertical, with a >5m thick strata looking like the one we saw at SF2, capped by a 1-1.5 m thick (laser) deposit presenting green/black horizontal centimetric layers. 09:57 Sampling fallen rocks that seem to be the dark/green deposit. SBS-665-197 10:00 ROV leaves the seafloor 10:32 ROV at the surface 11:01 ROV on board This folder also includes the files Subsaintes_renav.txt and sub-saintes2017_renav.mat including all renavigated data in a single file.

Post-cruise ROV Renavigation

Owing to problems with the inertial system and data acquisition (see report for details) some of the dives where not fully renavigated. Renavigated ROV track overlain on 'estime' tracks are shown in Figure 3.22.

ROV VICTOR 6000 samples

Rock sampling with the ROV Victor6000

Sampling with VICTOR allows to get a sense for the geological environment and to obtain a precise location for each of the sample. We tried to collect samples in situ, but this was not always possible in the case of massive lava flows or consolidated breccias/sandstones. We then collected loose blocks in the slope or at the base of the formation.

The samples are named with 3 letters corresponding to the cruise name, the dive number, and the sample number, that is sequential from the beginning of the cruise:

SBSxxx_yyy

Where xxx corresponds to the absolute Dive # and yyy to the sample#.

The samples are collected with the ROV's mechanical arm MAESTRO and put into the basket. The basket is divided into movable boxes that are labeled, and we keep the record of the label as the samples are stored. However, because of space requirement, it may happen that two samples are stored in the same box.

To avoid possible confusion and obtain the precise location of the sample, we have established a procedure that proved very efficient, and that builds on the experience from the ODEMAR cruise:

-before the dive, the position of the boxes in the basket is systematically recorded (photo, sketch)

-snaptshots of the sampling site and of the sample itself in the arm claws (to record its size and shape) are taken systematically -in addition to notes in the logbook -after the end of each sampling, the snapshots are recovered on the Science network -the most representative of the sampling process are selected -one is chosen to be the reference and is printed -with the time of this reference, the exact position (Lat, Long, Depth) is determined from the mimosa screen in the PC. These are written on the photo.

Post-cruise reprocessing of renavigation data provided new navigation files for the most part of the dives. These data have been used to update the sample positions to match the renavigated ROV tracks. These recalculated positions are reported in the Each rock sample is described, and a form with the description, location, and photos of outcrops and samples is available in the each of the folders SBSxxx available under the same folder 11_ROV_RockSamples.

Other relevant information related to the samples, including photos of the outcrops, moment of sampling, uncut and cut samples, etc, are available in each of the falders named Divexxx available under the same folder 11_ROV_RockSamples.

The working samples were then assigned to the different laboratories. A table compiling these working samples, SBS_Sampling.xlsx, and including information on the destination, and weights, is available in this same directory 11_ROV_RockSamples.

Finally, a summary of all the rock samples, with location information, setting, brief description, and selected photos, is available in the subsections for each of the dives included in Section 4.2 below.

As mentioned above, the positions reported in sections 4.2 onwards correspond to those recorded onboard, but the reference positions for any follow-up work should report those in the table SBS_master_sample_table_FINAL_NAV.xls, calculated using in priority the renavigated positions.

DIVE SBS654 along the North Roseau Fault

Coring with the ROV Victor6000

During dive #655 along the Rosseau Fault, we deployed the 4-tube minicorer on the NASA, and sampled the consolidated, darker sediment layer that is visible in the ODEMAR photomosaics showing cracks and fissuers, at the base of the Rosseau Fault scarp on the hanging wall. We cored along a line more or less perpendicular to the fault scarp, at distances of ~50 (core#1) to ~20 m (core #4) from the base of the scarp (see Figure 4.A).

Ship's multibeam surveys

Ship's multibeam echosounder EM122

R/V Atalante is equipped with a Multibeam echosounder Kongsberg EM122, emitting at a frequency of 12 KHz, allowing acquiring bathymetric and back-scatter data between 100 and 10,000 m bsl.

The emission beam, composed of different sectors, is 1ºx150º, while 288 reception beams image a surface of 2ºx32º at the seafloor. The MBES works in dual swath mode: 2 pings are emitted successively, at 0.5º forward and 0.5º backward.

Two different data are acquired:

-travel time of acoustic waves, allowing to calculate bathymetry -intensity of the reflected acoustic signal, allowing to calculate intensity of backscatter (also called imagery).

The geometry of the MBES results in:

-a vertical resolution less than 0.2% of the depth (see figure below) for angles less than ±60º; -a reflectivity precision of ± 1 dB; -a spatial (horizontal) resolution equivalent to 3 to 4 % of the depth (it can image objects larger than 3-4 m at 1000 mbsl).

EM122 Survey strategy

Two surveys were carried out during the cruise: #PL61 west of the study area on April 17 th , #PL62 south of the study area, along the Dominica slopes, on April 22 nd .

Ship bathymetry was not a priority during the cruise, and was carried out during down time.

Therefore complete processing of these data has been delayed and will be done later onshore. Bathymetric data were however corrected from ship attitude, manually cleaned and gridded at 10 m for a first validation. Back-scatter imagery was corrected by a statistical compensation and gridded in a mosaic.

We built our survey in order to have a good coverage (20 to 30 %) between bathymetric profiles, following the Ifremer-provided coverage diagram below. The emission angles were reduced between 80º/55º in order to keep the central beam signal only, and avoid noisy beams at extreme angles. Ship was heading at 8 knots, reasonable to have a good recoverage.

Figure 5.2. EM122 theorethical range

Before starting the surveys, Sippican sensors were launched. They record electric conductivity with depth, which allows estimating salinity and temperature gradient of the water column, and calculate sound velocity profiles, over the first 200 m approximately. On the basis of the LEVITUS data base, the sound velocity profile was completed at depth, to the sea floor. This velocity profile is used later in the processing in order to convert acoustic waves travel time into depth. Post-cruise, the processed data is available in Data Annex '20_Ship_Bathymetry' as grd grids with a spatial resolutions of 10 m (and the corresponding pdf maps):

EM122 survey #PL61, W of Roseau Fault

PL61_mnt_10m_Ssc_interp2.grd PL61_mnt_10m_Ssc_interp4.grd

EM122 survey #PL62, Dominica flank

Four profiles were acquired. Start of the survey: 20170422 at 15:25 End of the survey: 20170422 at 19:50

Bathymetry has been roughly processed with Caraibes software, and gridded with Sonarscope. Files generated onboard include:

Pl62_mnt_10m_Ssc.grd

In this grid, an artifact on Yanti volcano is present due to slope shadow. The MBES EM710 was turned on from profile 3, along the coast of Dominica, to Pointe-à-Pitre.

Post-cruise, the processed data is available in Data Annex '20_Ship_Bathymetry' as a grd grid with a spatial resolution of 10 m (and the corresponding pdf map), combined with data from PL63:

PL62_63_mnt_10m_Ssc_interp4.grd

Ship's multibeam echosounder EM710

R/V Atalante is equipped with a Multibeam echosounder Kongsberg EM710, emitting at a frequency of 70 to 100 KHz, allowing acquisition of bathymetric and back-scatter data at depths shallower than 1500 m bsl.

The emission beam, composed of different sectors, is 0.5ºx150º, while 200 reception beams image a surface of 1ºx26º at the seafloor. The MBES works in dual swath mode: 2 pings are emitted successively, at 0.5º forward and 0.5º backward.

Two different data are acquired:

-travel time of acoustic waves, allowing to calculate bathymetry -intensity of the reflected acoustic signal, allowing to calculate intensity of backscatter (also called imagery).

The geometry of the MBES results in:

-a vertical resolution less than 0.2% of the depth (see figure below) for angles less than ±65º; -a reflectivity precision of ± 1 dB; -a spatial (horizontal) resolution equivalent to 2 % of the depth (it can image objects larger than 2 m at 1000 mbsl).

EM710 survey strategy

The EM710 was turned on at the exit of the harbor, #PL60 on April 3 rd , as well as during the transit to the harbor, #PL63 on April 22 nd .

Ship bathymetry was not a priority during the cruise, and was carried out during down time.

Therefore complete processing of these data has been delayed and will be done later onshore. Before starting the surveys, Sippican sensor were launched and used for determining the sound velocity profiles. Bathymetric data were corrected from ship attitude, the tide, manually cleaned and gridded at 1 m for a first validation. Back-scatter imagery was corrected by a statistical compensation and gridded in a mosaic.

EM710, #PL60 Transit from Pointe-à-Pitre

Start of the survey: 20170403 at 12:00 End of the survey: 20170403 at 13:05

EM710 Survey and Transit #PL63 from Dominica slope to harbor

Two profiles were acquired on Les Saintes area (Figure 5.6).

Start of the survey: 20170422 at 17:12 End of the survey: 20170422 at 20:20

Then the MBES was stopped until our anchor station to wait for the pilot, before being turned on again for navigation purpose to the harbor (Figure 5.7).

Bathymetry has been roughly processed with Caraibes software, and gridded with Sonarscope.

PL63_mnt_10m_Ssc.grd

Post-cruise, the processed data is available in Data Annex '20_Ship_Bathymetry' as a grd grid with a spatial resolution of 10 m (and the corresponding pdf map), combined with data from PL62:

PL62_63_mnt_10m_Ssc_interp4.grd

Chirp survey & Kullenberg coring

During the Subsaintes cruise we conducted a single Kullenber core to investigate the possible traces or signature of sismites recorded in the sediment column. To carry out the Kullenber coring, we conducted first a survey of different sediment ponds to identify a coring station using the ship's chirp system, and then cored using a Kullenberg-type corer.

Chirp survey

The mud-penetrator echosounder (Chirp) produces acoustic chirp signal at a frequency centered on 3.5 kHz, on a broad range between 1800 -5500 Hz. The sounder emits a signal after receiving the previous one. Horizontal scale is therefore not constant in distance, neither in time.

Our survey lasted ~3h15' :

Start of acquisition: 20170408 13h32 End of acquisition: 20170408 16h44

To plot the chirp data, the sound velocity was set up at 1500 m/s. Depth is calibrated by mono-beam echo-sounder. 10 profiles were acquired, surveying 2 core sites.

Processing was carried out on board with SUBOP, a matlab-based software provided by Ifremer. Delays, ship attitude and spheric divergence are automatically corrected. SUBOP produces data reports, and concatenated profiles in PDF. Central part of profile 9 is empty due to copy error. Not recoverable.

SUBOP data reports and profiles provided in PDF for each profiles, together with other files, available in the DATA folder 12_Chirp.

Acoustic release

To recover the pressure sensor and mooring floats, we used an AR 6X1 acoustic release (type: AR 661 B2S DDL, serial number: 312) attached at the bottom the mooring to some iron chains used for ballast. Some tests of the material were done in the lab at Saint-Maur des Fossés prior to shipping (Figure Y).

The acoustic command suitcase is connected to a cable and a transducer head used to send acoustic commands that allow us to interrogate for for distance information, necessary to locate the mooring, or to send the release command of the mooring.

Mooring

The mooring was released near the Roseau Fault at 15°45.

Data from Adelie

For each dive, we converted several of the Adelie files for plotting on maps and other purposes:

• dimXXX.dbf files -informations on the snapshots acquired during the divewere converted to HTML, with links to the images folder, • nav_estimeXXX.dbf files -estimated navigation -were converted to date time x y z format (space separated), in folder 09_ROV_Navigation • ptrXXX.dbf files -points of interest -were converted to date time x y z name format (space separated) and also concatenated (all dives) in one CSV file ptr_all_dives.csv, in folder 09_ROV_Navigation • we extracted from dimXXX.dbf and science.xml (from ROV data) all informations about litter that we found on the seafloor. These informations are stored in litter_all_dives.csv, in folder 14_Litter

The converted files can also be found in :

WORK/ROV_VICTOR/extracted_from_Adelie along with the python scripts used in folder 15_Python

Cruise blog & outreach

For communication and outreach we maitained a blog on-line, targeting mainly a general-public audience, and including a section of data acquisition. The blog was updated almost daily. The blog is available at :

Subsaintes2017.weebly.com

The pdf of the different sections of the cruise web page are available under the folder 16_Outreach in the Data Annexes.

Cruise report Data Annex

This cruise report is associated with different files and folders that have been described in the corresponding sections above. In addition to these Data files, the directory 'Subsaintes_Backup' includes text files for all the har drives backed up onboard (AUV, ROV, science, working hard drives).

Figure 1 . 1 .

 11 Figure 1.1. Study area (dashed blue polygon) between the Les Saintes and Dominica

Figure 1 . 2 .

 12 Figure 1.2. 2004 Mw 6.3 seismic event and aftershock microseismicity, indicating the reactivation of the Roseau Fault (Bazin et al., 2010).

Fig. 1 . 3 .

 13 Fig. 1.3. Bathymetry map of the study area showing the different Faults and Volcanoes mapped, sampled, and studied during the Subsaintes'17 cruise.

Figure 1 . 4 .

 14 Figure 1.4. Details of shipboard bathymetry and SAR sonar data for different volcanoes in the area (modified from Leclerc et al., 2016).

Figure 1 . 5 .

 15 Figure 1.5. Map of ROV tracks (red), AUV tracks (blue) and location of sampling locations during VICTOR dives.

Figure 2 . 1 .

 21 Figure 2.1. AUV AsterX at the surface at the end of a dive, and being recovered within the Calisto Launch and Recovery system. Subsaintes2017 cruise.

Figure 2 . 2 .

 22 Figure 2.2. AUV AsterX on rails on the deck of the N/O l'Atalante

Figure 2 . 3 .

 23 Figure 2.3. Shaded shipboard bathymetry (Bathysaintes Cruise, PIs: N. Feuillet & C. Deplus) and AUV microbathymetry surveys (in colour). Numbers correspond to the AsterX dive numbers (see Table3.1).

Figure 2 . 4 .

 24 Figure 2.4. AUV track for Dive#394, corrected navigation

Figure 2 . 6 .

 26 Figure 2.6. AUV track for Dive#395, corrected navigation

Figure 2 . 8 .

 28 Figure 2.8. AUV track for Dive#396, corrected navigation

Figure 2 . 9 .

 29 Figure 2.9. AUV track for Dive#398, corrected navigation

Figure 2 .

 2 Figure 2.13. AUV track for Dive#400, corrected navigation.

Figure 2 .

 2 Figure 2.14. Globe 3D view of Carrata edifices and Roseau volcano (left), shipboard bathymetry wrapped with #400 acoustic back-scatter.

Figure

  Figure 2.17. AUV track for Dive#402, corrected navigation.

Figure 2 .

 2 Figure 2.26. AUV track for Dive#406, raw navigation.

Figure 2 .

 2 Figure 2.27. Globe 3D view of Redonde fault system and horsetail, shipboard bathymetry wrapped with #406 acoustic back-scatter.

Figure 2 .

 2 Figure 2.28. Globe 3D view of the area studied during dive#401 for AUV navigation and variations due to survey type/strategy.

Figure 2 . 30 .

 230 Figure 2.30. Attitude for a survey with immersion specified, descending (left, File 3) and ascending (right, File 4). Note that the pitch peaks corresponds to periods of sudden ascent or descent of AsterX.

Figure 2 .

 2 Figure 2.31. AUV pitch during bottom tracking immersion during descent (blue, File 1) and ascent (red, File 2).

Figure 2 .

 2 Figure 2.32. AUV pitch during immersion assigned survey during descent (blue, File 3) and ascent (red, File 4).These peaks in pitch during ascent and descent do correspond to the same location spatially (Mean pitch view, Figure2.33).

Figure 2 .

 2 Figure 2.33. Along-track plot of Mean pitch (°) for the during descent (blue, File 3) and ascent (red, File 4) with the AUV flying with immersion pre-defined.The rest of the dive was flown with immersion pre-defined. File 5, corresponding to the start of the survey, is done in descent (Figure2.34).

Figure 2 . 34 .

 234 Figure 2.34. Microbathymetry projected in 3D of File 5, corresponding to the start of the survey, flown with pre-defined immersion, and following the navigation/attitude tests (Files 1 through 4) during dive #401.

Figure 2 . 35 .

 235 Figure 2.35. Vehicle attitude during start of survey (File 5, Dive #401), flown with predefined immersion.

Figure 2 . 36 .

 236 Figure 2.36. Vehicle attitude, File 14, Dive#394.

Figure 2 . 37 .

 237 Figure 2.37. Bathymetry and navigation during Dive#394. The flight track in green corresponds to File 14 shown in Figure 2.36.

Figure 2 . 38 .

 238 Figure 2.38. Vehicle attitude, File 24, Dive#394.

Figure 2 .

 2 Figure 2.39. Bathymetry and navigation during Dive#394. The flight track in green corresponds to File 44 shown in Figure 2.36, ascending and descending the volcanic mound at Crawen volcano.

Figure 2 . 40 .

 240 Figure 2.40. Compilation of bathymetric surves conducted by AsterX during the SUB-SAINTES'17 cruise.

Figure 2 .

 2 Figure 2.41. Microbathymetry from AUV dive #394.

Figure 2 . 42 .

 242 Figure 2.42. Microbathymetry from AUV dive #395.

Figure 2 .

 2 Figure 2.43. Microbathymetry from AUV dive #396.

Figure 2 .

 2 Figure 2.44. Microbathymetry from AUV dive #397.

Figure 2 . 45 .

 245 Figure 2.45. Microbathymetry from AUV dive #399.

Figure 2 . 46 .

 246 Figure 2.46. Microbathymetry from AUV dive #400.

Figure 2 . 47 .

 247 Figure 2.47. Microbathymetry from AUV dive #402.

Figure 2 . 48 .

 248 Figure 2.48. Microbathymetry from AUV dive #403.

Figure 2 . 49 .

 249 Figure 2.49. Microbathymetry from AUV dive #404.

Figure 2 .

 2 Figure 2.50. Microbathymetry from AUV dive #405.

Figure 2 .

 2 Figure 2.51. Microbathymetry from AUV dive #406.

Figure 2 .

 2 Figure 2.52. Comparison of AUV's raw navigation and processed navigation, AUV Dive#403.

Figure 2 .

 2 Figure 2.53. Inter-ping distance (m) of dive 399, plotted over the navigation profiles.

Figure 2 .

 2 Figure 2.54. A raw mosaic processed, Dive #403.

Figure 2 . 55 .

 255 Figure 2.55. Compensation curve calculated for the backscatter in File 32 of Dive #403.

Figure 2 . 56 .

 256 Figure 2.56. Sonarscope window to implement backscatter compensation for an AUV dive.

Figure 2 .

 2 Figure 2.57. A compensated sonar mosaic, Dive #403.

Figure 2 .

 2 Figure 2.58. Installation of the Eh sensor (with blue caps) and cabling within AsterX.

Figure 2 . 59 .

 259 Figure 2.59. Example of Eh values along track (top left), as a function of depth (top right) and of time (bottom). AUV dive#394.

Figure 3 . 1 .

 31 Figure 3.1. Bathymetry of the study area with ROV VICTOR6000 tracks (navigation 'estime').

Figure 3 . 2 .

 32 Figure 3.2. Illustration of the reference frame used for the ROV positioning data © IFREMER. Adapted from "POSITION DES CAPTEURS PAR RAPPORT AUX REPER-ES CRN ET CRP", IFREMER N° de rattachement B.E : VICTOR.V.00.00.DG08

  Figure 3.3. Example of 2D OTUS2 survey, with blended photomosaic (above) and ROV tracks over the microbathymetry (below).

Figure 3 . 4 :Figure 3 . 5 :Figure 3 . 6 :

 343536 Figure 3.4: 3D model, ~150 m long and ~25m high, of a fault scarp reconstructed from data acquired in dives 654 and 658 -model AUTT28_KI

Figure 3 . 7 :

 37 Figure 3.7: Map of laser measurements conducted during the SUBSAINTES cruise. Red dots correspond to renavigated positions, and black dots correspond to sites where no renavigated data exists, and the 'estime' navigation is used instead. Green circles correspond to positions recorded onboard (including some erroneous ones). Red tracks correspond to renavigated ROV positions, magenta to 'estime' ROV navigation, and cyan to tracks from the ODEMAR-Les Saintes cruise. Numbers correspond to the measurement index. The laser data information is available file LASER_final.txt in Data Annex folder 19_LASER.

Figure 3 .

 3 Figure 3.13. ROV track for dive #658 (black), and sample locations (red stars with numbers) overlain on shipboard bathymetry.

Figure 3 .

 3 Figure 3.14. ROV track for dive #659 (white), and sample locations (red stars with numbers) overlain on microbathymetry.

Figure 3 . 15 .

 315 Figure 3.15. Detail of the volcanic dome at Crawen showing ROV track for dive #659 (white), and sample locations (red stars with numbers) overlain on microbathymetry.

Figure 3 . 16 .

 316 Figure 3.16. Detail of the volcanic dome at Crawen showing ROV track for dive #660 (black),and sample locations (red stars with numbers) overlain on microbathymetry and regional shipboard bathymetry.

Figure

  Figure 3.17. ROV track for dive #661 (black), and sample locations (red stars with numbers) overlain on microbathymetry.

Figure 3 .

 3 Figure 3.18. ROV track for dive #662 (black), and sample locations (red stars with numbers) overlain on microbathymetry.

Figure 3 .

 3 Figure 3.20. ROV track for dive #663 (black), and sample locations (red stars with numbers) overlain on microbathymetry.

Figure 3 .

 3 Figure 3.21. ROV track for dive #665 (black), and sample locations (red stars with numbers) overlain on microbathymetry.

Figure 3 .

 3 Figure 3.22. ROV track for dive #666 (black), and sample locations (red stars with numbers) overlain on microbathymetry.

Figure 3 .

 3 Figure 3.23. Renavigated ROV tracks (red) overlain on 'estime' navigated tracks (black).

Figure 4 . 1 .

 41 Figure 4.1. Location of the cores (#1 to the NE and #4 to the SE) along a transect subperpenticular to the fault scarp, indicated by the warm colours corresponding to the terrain slope calculated from ODEMAR ROV microbathymetry.

Figure 5 . 1 .

 51 Figure 5.1. EM122 evaluation of precission at 4500 m depth

FourFilesFigure 5

 5 Figure 5.3. #PL61 Bathymetry data acquired with EM122 (color) and ship tracks (black lines), overlain on shaded B&W BATHYSAINTES 10m grid.

Figure 5

 5 Figure 5.4. #PL62 Bathymetry data acquired with EM122 (color) and ship tracks (black lines), overlain on shaded B&W BATHYSAINTES 10m grid.

Figure 5 .

 5 Figure 5.5. #PL60 Bathymetry data acquired with EM710 (color) and ship tracks (black lines), during transit from Point-a-Pitre.

Figure 5

 5 Figure 5.6. #PL63 Bathymetry data acquired with EM710 (color) and ship tracks (black lines), in Les Saintes area.

Figure 5

 5 Figure 5.7. #PL63 Bathymetry data acquired with EM710 (color) and ship tracks (black lines), heading to the harbor.

Figure 6 . 1 .

 61 Figure 6.1. Chirp profiles (black and red lines), and location of core SBS-17-PC-001 (yellow circle)

Figure 7 . 1 .

 71 Figure 7.1. Configuration parameters of the SBE39 pressure sensor

Figure 7 . 2 .

 72 Figure 7.2. Acoustic release, command suitcase, and transducer used to transmit commands to the acoustic releas.

Figure 7 . 3 .

 73 Figure 7.3. Sketchf the mooring used to deploy the Seabird SBE39 pressure sensor.

Figure 7 . 4 .

 74 Figure 7.4. Map showing the crossing of the ranging from three different positions (coordinates in UTM).

Figure 7 . 5 .

 75 Figure 7.5. Top : Depth converted from the pressure recording using the Seabird SBE39. Bottom : comparison of the recorded tide (black) and the predicted tide provided by the SHOM (France) for this area (red).

Figure 7 . 6 .

 76 Figure 7.6. Detail of the comparison between the recorded and predicted tide, showing the ~1h lag of the predicted tide.

Figure 7 . 7 .

 77 Figure 7.7. Detail of the tide record showing the peaks, with an amplitude of up to 0.8 m, at the same tidal phase.

Table 2 .

 2

	Dive	Date	Survey time	Distance Area map Flight	Location
	#394	20170404	08h26'	51.0 km	8.7 km 2 Bottom track Crawen V
	#395	20170405	07h03'	40.2 km	6.2 km 2 Bottom track Agoucha V South
	#396	20170407	07h56'	44.2 km	10.2 km 2 Bottom track Souffleur F.
	#397	20170408	N/A	N/A	0 km 2 Aborted
	#398	20170409	08h41'	47.3 km	7.0 km 2 Bottom track Crawen V
	#399	20170410	09h43'	43.0 km	7.8 km 2 Bottom track Colibri V
	#400	20170411	12h22'	68.0 km	13.6 km 2 Bottom track Roseau V
	#401	20170413	01h04'	7.7 km	1.4 km 2 Immersion	Roseau F Canyons
	#402	20170415	08h29'	47.5 km	9.7 km 2 Immersion	Roseau F Canyons
	#403	20170417	08h26'	45.9 km	7.2 km 2 Immersion	Coche V
	#404	20170419	09h05'	39.0 km	7.0 km 2 Immersion	Roseau V South
	#405	20170421	09h25' 50.643 km	10.8 km 2 Immersion	Roseau V South/2
	#406	20170422	11.8 hours	71.5 km	9.3 km 2 Immersion	Redonde
		total*:	99h51'	533.5 km	98.2 km 2
		avg.*:	7.4 hours	41.0 km	7.6 km 2

1: AUV Mission statistics for cruise ODEMAR.

*Survey time = time spent mapping near the seafloor; distance = distance travelled near the seafloor; Averages do include the aborted and shortened dives #397 and #401.

  This back-scatter mosaic was produced with Sonarscope. A statistic compensation was applied from the curve processed, but not really effective on this type of relief. The raw mosaic is preferred. Mosaic gridded at 0.75 m, then new navigation calculated by Ifremer applied. Connection troubles inside the AUV, between the INS and the MBES PU, inferred cuts in attitude measures and recording. The new navigation file from Ifremer, Toulon, should fix that but Sonarscope team has to provide a new setup to adapt to this new navigation format. This new navigation format (corrected position and attitudes instead of corrected position only) is also provided for dive 402. From dive 403, cable trouble is fixed.

	2.3.9 AUV Dive #402 -Roseau Fault Canyon segment
	AUV Dive # 402
	Dive duration: 09 :54	Survey duration : 08 :29
	AUV in water: 20170415 at 11:39
	Start of the survey: 20170415 at 11:58
	End of the survey: 20170415 at 20:27
	On deck time: 20170415 at 21:08
	Distance on-bottom:	47.473 km
	Multibeam echosounder EM2040 : on	Nephelometer : on	Eh : off
	Survey area: Roseau fault / Canyon segment
	Information about Data and Processing :
	PL402_mnt_1m_prenav_Ssc.mnt
	PL402_mnt_1m_prenav_Ssc.grd
	PL402_mnt_1m_prenav_8_9_10_Ssc.mnt
	PL402_mnt_1m_prenav_8_9_10_Ssc.grd
	PL402_mnt_1m_prenav_32_to_37_Ssc.mnt
	PL402_mnt_1m_prenav_32_to_37_Ssc.grd
	Produced back-scatter mosaics :
	MosaicRaw_Postnav_SansAngles_AUV-PL401_AvecTraversiers_0,75m_interp.grd
	MosaicRaw_Postnav_SansAngles_AUV-PL401_SansTraversiers_0,75m_interp.grd

Produced bathymetric grids (mnt and grd): PL401_mnt_1m_prenav_Ssc.mnt PL401_mnt_1m_prenav_Ssc.grd Grids are corrected from tide, rolling, and manually cleaned. We used raw navigation. Profiles 3 and 4 in auto-immersion mode have shown better quality data than profiles 1 et 2. Gaps in data coverage seen during sharp slope rising of the AUV have been reduced by the auto-immersion mode.

Water-column comments : Polar echograms and echo-integration has been produced. Nothing to see. Figure 2.15. AUV track for Dive#401, corrected navigation.

Figure 2.16. Globe 3D view of Roseau Fault, Canyon segmentshipboard bathymetry wrapped with #401 acoustic back-scatter. Geometry : 10 NW-SE profiles along the Canyon segment of the Roseau fault, west of Les Saintes plateau.

Renavigated Y/N ? yes General Comments : The bathymetry seems to be improved with the new autoimmersion configuration decided for the AUV. To be confirmed with dive #403.

Produced bathymetric grids (mnt and grd):

2.17. AUV track for Dive#402, corrected navigation. Figure 2.18. Globe

	2.3.10 AUV Dive #403 -Coche Volcano
	Dive duration: 08 :26	Survey duration : 09 :36
	AUV in water: 20170417 at 12:16
	Start of the survey: 20170417 at 12:34
	End of the survey: 20170417 at 21:00
	On deck time: 20170417 at 21:27
	Distance on-bottom:	45.936 km
	Multibeam echosounder EM2040 : on	Nephelometer : on	Eh : on
	Survey area: Coche volcano
	Information about Data and Processing :
	Geometry : 10 NW-SE profiles over the Coche volcano. 11 SW-NE profiles over the
	Coche fault, and 3 NE-SW profiles over Roseau volcano.
	Renavigated Y/N ? yes
	General Comments :
	Acquisition was configurated in auto-immersion depth when the profiles were paral-
	lel to the isobaths, and in auto-altitude mode otherwise.
	Bathymetric data are less noisy and the survey is of very good quality.
	Produced bathymetric grids (mnt and grd):
	PL403_mnt_1m_prenav_Ssc.mnt
	PL403_mnt_1m_prenav_Ssc.grd
	Grids are corrected from tide, and manually cleaned. We used raw navigation.
	Produced back-scatter mosaics :
	MosaicRaw_Postnav_AUV-PL403_AvecTraversiers_0,75m_interp.grd
	MosaicRaw_Postnav_AUV-PL403_SansTraversiers_0,75m_interp.grd
	This back-scatter mosaic was produced with Sonarscope. A statistic compensation
	was applied from the curve processed over file 32. Mosaic gridded at 0.75 m, using
	post-processed navigation calculated by Ifremer (Delphins software).
	Water-column comments : Polar echograms and echo-integration has been produced.
	Nothing to see.

3D view of Roseau Fault, Canyon segment, shipboard bathymetry wrapped with #402 acoustic back-scatter.

Figure 2.19. AUV track for Dive#403, corrected navigation. Figure 2.20. Globe

	2.3.11 AUV Dive #404 -West Roseau Volcano and Roseau Fault segments
	Dive duration: 09 :05	Survey duration : 08 :35
	AUV in water: 20170419 at 12:25
	Start of the survey: 20170419 at 12:46
	End of the survey: 20170419 at 21:21
	On deck time: 20170419 at 21:51
	Distance on-bottom:	39 km
	Multibeam echosounder EM2040 : on	Nephelometer : on	Eh : on
	Survey area:

3D view of Coche volcano and faults, shipboard bathymetry wrapped with #403 acoustic back-scatter.

West Roseau volcano and Roseau fault segments.

	Information about Data and Processing :
	Geometry: Nine profiles NW-SE striking, following the faults. One perpendicular
	transect.
	Renavigated Y/N ? Yes but not complete (map below shows navigation without
	correction)
	General Comments:
	Acquisition was configurated in auto-immersion depth when the profiles were paral-
	lel to the isobaths, and in auto-altitude mode otherwise. Many swerve events. Post
	processed navigation is valid only for profiles from 1 to 17.
	Produced bathymetric grids (mnt and grd):
	PL404_mnt_1m_prenav_Ssc.mnt
	PL404_mnt_1m_prenav_Ssc.grd
	Grids are corrected from tide, and manually cleaned. We used raw navigation. The
	map show still some artefacts due to many swerve events.
	Produced back-scatter mosaics:
	MosaicComp_Prenav_AUVPL404_Decoupe_SansTraversiers_0,75m_interp.grd
	MosaicComp_Prenav_AUV-PL404_SansTraversiers_0,75m.kmz
	MosaicRaw_Prenav_AUV-PL404_Decoupe_SansTraversiers_0,75m_interp.grd
	This back-scatter mosaic was produced with Sonarscope. A statistic compensation
	was applied from the curve processed over file 9. Mosaic gridded at 0.75 m, using
	raw navigation.
	Water-column comments: Polar echograms and echo-integration has been produced.
	Potential flares are spotted in pings number 269 and 315 of file 22:

Figure 2.21. AUV track for Dive#404, raw navigation. Figure 2.22. Globe

	2.3.12 AUV Dive #405 -West Roseau Volcano & faults
	Dive duration: 10 :08	Survey duration : 09 :00
	AUV in water: 20170421 at 11:25
	Start of the survey: 20170421 at 11:57
	End of the survey: 20170421 at 20:57
	On deck time: 20170420 at 21:33
	Distance on-bottom:	53 km
	Multibeam echosounder EM2040 : on	Nephelometer : on	Eh : on
	Survey area:
	Figure 2.23. Watercolumn acoustic backscatter with possible signals in above Roseau volcano
		highs in southern section of plateau.

3D view of Roseau volcano and faults, shipboard bathymetry wrapped with #404 acoustic back-scatter.

West Roseau volcano and fault segments of Le Havre and Colibri. Navigating at 35 m above seafloor where we suspect hydrothermal vent on Roseau volcano. Linking the other AUV surveys of the area and completing the coverage of the volcano.

	Information about Data and Processing :
	Geometry : First NE-SW profile over the potential hydrothermal site, then 6 NNE-
	SSW profiles over the faults. Following the northern edge of the Rosaeau volcano
	plateau to the northeast, crossing surveys 404 and 403. Five NW-SE profiles, two
	more along the Coche fault graben. Four E-W profiles.
	Renavigated Y/N ? not yet
	General Comments :
	Acquisition was configurated in auto-immersion depth when the profiles were paral-
	lel to the isobaths, and in auto-altitude mode otherwise.
	Produced bathymetric grids (mnt and grd):
	PL405_mnt_1m_prenav_Ssc.mnt
	PL405_mnt_1m_prenav_Ssc.grd
	Grids are corrected from tide, and manually cleaned. We used raw navigation. The
	survey is of a very good quality event without post processed navigation data.
	Produced back-scatter mosaics :
	MosaicCompPrenav_AUV-PL405_Sanstraversiers_0,75m_interp.grd
	SlopeMax_Prenav_AUV_PL405_SansTraversiers_O,75m.grd
	This back-scatter mosaic was produced with Sonarscope. A statistic compensation
	was applied from the curve processed over file 42. Mosaic gridded at 0.75 m, using
	raw navigation. Corrected navigation is not available yet as it is week-end.
	Water-column comments : Polar echograms and echo-integration has been produced.
	Potential flares are spotted in ping number 114 of file 3, at the same place than the
	ones spotted in dive 404.

Figure 2.24. AUV track for Dive#405, raw navigation. Figure 2.25. Globe

	2.3.13 AUV Dive #406 -Redonde Fault system
	Dive duration: 10 :03	Survey duration : 09 :22
	AUV in water: 20170422 at 11:44
	Start of the survey: 20170422 at 12:25
	End of the survey: 20170422 at 21:17
	On deck time: 20170422 at 21:47
	Distance on-bottom:	5.0 km
	Multibeam echosounder EM2040 : on	Nephelometer : on	Eh : on
	Survey area:
	3D view of volcano, shipboard bathymetry wrapped with #405 acoustic
		back-scatter.

Redonde fault system and horsetail

	Information about Data and Processing :

Table 3 . 1 .

 31 Summary of ROV Victor Dives, their on-bottom duration, the approximate length of the track at the seafloor, and the overall location of the dive.

	Dive #	On bottom	Off bottom	Duration Length, m Location
	653	03/4/17 -23:09:38	04/4/17 -09:07:24	09:58	3460	Roseau F. Center
	654	05/4/17 -00:14:05	05/4/17 -10:16:02	10:02	4390	Roseau Fault N
	655	06/4/17 -00:37:18	07/4/17 -09:15:43	34h37	20515	Roseau Fault S
	656	07/4/17 -23:43:26	08/4/17 -09:12:23	09:29	5141	Agoucha 1
	657	08/4/17 -22:09:26	09/4/17 -09:25:57	11:16	6283	Agoucha 2
	658	10/4/17 -00:43:08	10/4/17 -09:18:31	08:35	6738	Roseau C&N
	659	10/4/17 -23:40:06	11/4/17 -20:36:03	20:56	10088	Crawen
	660	12/4/17 -14:18:05	13/4/17 -14:32:34	24h14	16136	Crawen
	661	14/4/17 -10:23:11	15/4/17 -08:30:32	22h07	10728	Colibri
	662	16/4/17 -00:08:33	17/4/17 -09:12:48	33h04	18792	Roseau V
	663	18/4/17 -03:49:32	19/4/17 -08:56:31	29h07	23760	Roseau Canyons/Coche
	664	19/4/17 -23:31:39	21/4/17 -08:59:42	33h28	22586	Roseau V. / Coche
	665	22/4/17 -01:38:20	22/4/17 -10:01:15	08:23	4855	Souffleur
	666	23/4/17 -00:33:05	23/4/17 -13:53:51	13:20	7626	Roseau V S
	Total			257:47	161098
	Average			18 :25	11507	0.625 km/h
				Duration	Length

  [dive, date, time, im_source, im_source_fmt, im_filename, lat, lon, depth, alt, yaw, roll, pitch, X_speed, Y_speed, Z_speed, RX_speed, RY_speed, RZ_speed, cam_pan, cam_tilt, cam_zoom, cam_focus,cam_iris, event_name, tag, comment] =textread('otus653.txt','%n %s %s %s %s %s %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %s %s %s %*[^\n]','delimiter',';','emptyvalue',NaN);

Table 3 .

 3 2. 2D Imagery acquisitions

	Dive	Start time	End time	Sites Covered	Comment
		20170405 01:29			Otus survey on dejection cone
		20170405 06:43	07:23		Dejection cone NW of FPQ
		20170606 00:53	05:40	AUTT 39-62	See Summary-Dive655_Final.docx
		20170606 06:19 06:40	AUTT 64, 65, 66
		9:31	??	AUTT74	25m along scarp
		12:48	13:30	AUTT84,87
		13:43	13:59	AUTT88,89	"tracking linear structure/cracks with OTUS"
				AUTT 101, 91,
		19:49	22:36	111, 112, 113,114

, 116, 117 Photomosaic survey, usable sec- tions are approx 20:16-20:33 (3 transects) and 21:41-22:36 (sev- eral transects). At 21:41 start OTUS transect away from fault, over 2013 mosaic area. Fractures in sediments imaged farther than in 2013 mosaic. 20170407 4:00 09:15 AUTT 110 to 147 Approx. 14 profiles for photomo- saicing. See Summary-

					deposits covered by sediments
	659	????	11:35	AUTT46 to 50
	659	11:51	12:20
	662	20170415 02:15	02:55	AUTT22 and 23
	662	????	13:46	AUTT29 to 37
					Dive655_Final.docx
		20170408 00:33	00:58		OTUS started over lava flow
		4:47	5:32	AUTT_166
		6:24	7:10	AUTT_168 and 169
		20170409 00:45	00:59	AUTT13
		04:27	0616	AUTT30	Approx. 10 transects for photo-mosaicing
		06:54	07:34	AUTT32 to 34
		08:08	09:25	AUTT 35 to 38
		20170409 02:08	02:15		alternating outcrops and sedi-ments with ripples
					OTUS from 5 to 4, distributed de-
		04:42	04:55		formation, numerous subparallel
					fractures
		??	07:20	AUTT7, AUTT9 SBS_658_56
		7:43	09:18	AUTT 12 and 15
		07:30	08:58	AUTT-45	summit caldeira, subhorizontal

Table 3

 3

		.3. Otus2 surveys (>20 images)
						#
	Dive	Survey Name	Begin time	End time	Duration	Frames
		acq_20170404T025147 04-Apr-2017 02:51:53 04-Apr-2017 03:59:57 1:08:04

Table 3 .

 3 4. Summary of video sequences for 3D reconstruction

	Dive	Start time	End time	Model	Comment
	653	04/04/2017 02:20	04/04/2014 02:08 FPB_AA	Fault scarp
	654	00:36 05/04/2017	05/04/2014 00:53 FPA_AA	Fault scarp
	654	05/04/2017 02:42	05/04/2014 03:00 AUTT18_AA	Vertical video
	654	05/04/2017 04:57	05/04/2014 05:23 AUTT28_AA	Maybe 3 sub-scarps
	654	05/04/2017 07:03	05/04/2014 07:12 FPQ_AA
	655	06/04/2017 06:30	06/04/2014 06:37 AUTT66_AA	Fault plane broken by dejection cone
	655	06/04/2017 18:35	06/04/2014		Fault scarp
	655	06/04/2017 22:43	06/04/2014 22:49 VerticalTransect_AA vertical transect along the scarp
	656	08/04/2017 03:09	08/04/2017 03:30 AUTT162_AA	deep depression
	657	09/04/2017 00:51	09/04/2017 01:00 Fissure2_AA	Fissure
	657	09/04/2017 06:32	09/04/2017 06:42 AUTT31_AA	old fault plane, 2 parallel fault scarps
	657	09/04/2017 07:31	09/04/2017 07:39 AUTT33_AA
	657	09/04/2017 07:48	09/04/2017 07:58 AUTT34_AA
	658	10/04/2017 01:00	10/04/2017 01:03		Repeat of FPB
	658	10/04/2017 01:37	10/04/2017 01:50		Repeat of AUTT18

Table 3 . 5 .

 35 Thumbnails of the snapshots of all 3D model for visual referenceDuring the ROV dives, we acquired imagery of outcrops and geological features with the lasers to provide quantitative measurements of these structures. VICTOR is equipped with 4 red lasers that project to a square ~16.5 cm per side. During the cruise the dates/times of laser measurements where recorded, and images grabbed from the video records. The folder 19_LASER in the Data Annex includes:Laser.xls: Original table with laser measurements and positions recorded onboard. Folder containing image grabs for each of the ROV dives. Images are organized in a folder per dive, and with a filename including the date/time stamp.Post cruise the laser measurements where re-positioned using the renavigated ROV data. The folder 19_LASER in the Data Annex includes the file LASER_final.txt with the data, with the 16 columns defined in the file LASER_final_README.txt:

	FPB_AA
	Dive 653
	04/04/2017
	FPA_AA
	Dive 654
	05/04/2017
	AUTT18_AA
	Dive 654
	05/04/2017
	AUTT28_AA
	Dive 654
	05/04/2017
	FPQ_AA
	Dive 654
	05/04/2017

Photos:

Figure 3.8. ROV

  , stop -start OTUS, cap 250° 08:29 AUTT145, stop -start OTUS, cap 17° away from the scarp; changed 08:36 black thin line on the sediment sea floor, parallel to the scarp 08:43 pock mark 08:45 AUTT146, stop -start OTUS, cap to RSK towards the scarp 09:00 AUTT146, starting OTUS profile to RSK; see several pock marks 09:15 AUTT147: end of dive 655 OTUS stopped at 2/3 of the profile to RSK

	07:26 ROV problems 3.5.2 ROV Dive #654 -Roseau Fault N 03:42 Fault scarp: laser measure, AUTT24 3.5.2 ROV Dive #655 -Roseau Fault S 08:00 AUTT14405:31 OTUS survey, 2sec photos acquisition 02:42 vertical transect at tomb stone
	08:13 Fault plane near FPC, 1061 m Dive duration: 12:31 03:46 Consolidated sediments: try to sample, AUTT25 Dive duration: 35:23 05:34 start OTUS to 130° 02:49 going to AUTT19 (end Dive654)
	08:50 Sample on coseismic scarp near FPC -SBS-653-010 -1070m Work at bottom duration: 10:02 04:17 SBS-654-016, AUTT26, 1067m Work at bottom duration: 34:37 05:39 passage over scarp, dip SW 03:43 arriving at AUTT2, brecciated lava flow 3.5.1 ROV Dive #653 -Roseau Fault C 08:57 SBS-653-011 & SBS-653-012 on fault plane (12 lost) On bottom: 20170405 00:14 04:57 Maybe 3 sub-scarps, AUTT28, Start 3D survey On bottom: 20170406 00:37 05:43 OTUS survey, cap 270 03:49 Laser measurement in slope, ~20cm, AUTT3, scarp ~20cm laser measurement, Dive duration: 12:54 09:06 End of dive Off bottom: 20170405 10:16 05:23 End 3D survey, laser north of FPO Off bottom: 20170407 09:16 05:48 OTUS survey, change azimuth to 035 sand cover Work at bottom duration: 9:58 On bottom: 20170403 Distance on-bottom: 4.4 km 05:34 Laser measure AUTT31 Distance on-bottom: 20.5 km 05:53 end OTUS survey on relay 03:54 Laser measurement on scarp, ~1.12m, next to AUTT4 23:09 Off bottom: 20170404 Basket: Autonomous temperature sensor + Rock sampling arrangement Y 05:46 Laser measure AUTT32 Basket: Autonomous temperature sensor + Rock sampling arrangement Y/N? Y 05:58 end OTUS photomosaic survey at AUTT30, headed to AG31 03:58 Laser measurement on scarp ~80cm-1m, AUTT5 09:07 Distance on-bottom: 05:59 Laser measure AUTT33 05:59 start OTUS for seafloor survey 04:12 Laser measurement of scarp, ~30cm, crumbly scarp in carbonate sand 3.4 km Goals 06:16 Hydraulic problem with ROV arm, interest point H Goals 06:10 Laser measurement on lava flow, ~40cm 04:15 Laser measurement, ~40cm, crumbly limestone Basket: Autonomous temperature sensor + Rock sampling arrangement Inspect fault planes for coseismic displacement markers 06:34 Arrive at FPQ, ~20m scarp Map the coseismic rupture towards the S of FPA 06:16 end OTUS, sampling piece of lava flow at scarp base SBS_657_51, close to 04:19 scarp recovered by slumping, large breccia blocks collapsed
	Inspect cone for reactivation or not 06:43 Start OTUS survey Inspect, map deformation features subparallel to coseismic scarp & in hanging wall AUTT31 04:21 no scarp visible, breccia Goals Sampling of volcanic layers at the base of the scarp 06:45 Dejection cone NW of FPQ 3D video 06:32 AUTT31 start 3D video on old fault plane, 2 parallel fault scarps 04:26 Laser measurement on fissure in sediments, slabs of breccia fractured and Investigate nature of uppermost sedimented terrain away from fault scarp 07:03 Fault scarp: start 3D video Sampling of volcanic layers at the base of the scarp 06:42 end 3D video, laser measurements slumped Inspect fault planes for coseismic displacement markers Summary 07:12 Fault scarp: end 3D video OTUS survey deformation features 06:54 possible other fault scarp, laser measurements ~3x16cm, start OTUS 04:30 coseismic fracture in OTUS Inspect cone for reactivation or not Landed on scarp near FPA and photomosaic survey on cone at FPA 07:23 Ship problem: dynamic positioning, ROV drift due pull, OTUS stopped 06:56 AUTT32 changing lithology, from lava flow to lighter rock, sampling 04:33 3D survey on fractures breccia zone with laser measurement for scale Sampling of volcanic layers from base to top of the scarp 3D mosaic at FPA, FPQ, route to the NW 07:34 Exploration continues NW Summary SBS_657_52 04:39 AUTT6 start 3D photo survey, moving to right of fractured breccia
	Sampling along the fault scarp 07:41 Laser measure Landed in southern end of double fault scarp near RSE 07:05 AUTT33 sediments sticked on the fault plane, recent? 04:42 OTUS from 5 to 4, distributed deformation, numerous subparallel fractures Summary Identified and sampled several fault scarps and dejection cones, with coseismic dis-08:08 Start OTUS survey OTUS of old fault scarp, sub-parallel en-echelon scarps, damage in the hanging-wall 07:11 AUTT34 laser measurement ~10cm 04:48 subparallel fractures on terrace, step in middle of scarp Rippled seafloor is sandy (not possible to core) placements of ~1 m measured with laser points, up to 1.40 m 08:22 SBS-654-017: crust above white formation and pockmarks. 07:31 AUTT33: start 3D video 04:55 end OTUS, Laser measurement for scaling survey Landed NW of FPA and identified several fault scarps and dejection cones, with co-OTUS of dejection cone between FPF and FPG 08:26 SBS-654-018: white formation Remarquable features: fault scarp, fault planes and coseismic fault plane, striations, 07:34 stop OTUS 04:59 small scarp/fracture, <16cm in midslope flat area, coseismic, laser measure-seismic displacements of ~1 m visible Significant features: striations, sub-scarps 08:36 White bed dipping to the north sub-scarps, rock pavement, fissures and pockmarks 07:39 end 3D video ment At FPA sampling unsuccessful 3D video of scarp and sediments 09:05 Breccia, SBS-654-019, AUTT35 3D video of old fault plane 07:45 AUTT34, laser measurement 05:03 other tiny scarp <10cm, basal breccia of lava flow, SBS_654_13 FPB with nice coseismic displacement -3D survey Some hydraulic problems with ROV (basket and arms) 07:48 3D video 05:12 top of scarp, no deformation, going down another profile OTUS of dejection cone between FPA and FPB Ship dynamic positioning problem led to ROV drift due to being pulled Chronology 07:58 end 3D video 05:14 scarp midslope, coseismic, laser measurement ~40cm Sampling above FPA over fault scarp 08:08 AUTT35 fault scarp, visible displacement, laser measurement ~30cm, sampling 05:19 no scarp
	Chronology 20170606 plane SBS_657_053, OTUS started 05:21 zone of numerous fractures
	20170405 00:36 Victor at bottom (after loss of images and communication) 08:23 AUTT36, laser measurement ~20cm 05:23 coseismic scarp, laser measurement, 3D profile Chronology 00:15 Victor at bottom -on scarp 00:44 POI AUTT 36 fault scarp (rockslide at base) 08:30 volcanic blocks 05:36 fractures on seafloor
	00:25 Breccia, slightly stratified, with some big blocks 00:52 POI AUTT 37 old degraded fault polished surface 08:41 AG34 base of lava flow, fractured, breccia, heading to 318 then 4° 05:38 start profile up slope scarp, start of subparallel coseismic fracture 20170303 00:36 Fault scarp: 3D mosaic at FPA, clear vertical coseismic displacement 00:53 POI AUTT 39: small Fault scarp, OTUS done vertical on top of fault plane 08:57 AUTT37 sampled SBS_657_54 pahoehoe lava, breccia just above, AUTT38 05:39 AUTT7 1st major coseismic scarp, laser measurement 23:09 Victor at bottom -sedimented with ripples 00:54 Fault scarp: exploration to NW, some blocks, white levels of stratification 01:10 AUTT 40 Fault scarp (base) avoiding moving rope (net?) 05:48 AUTT9 SBS_658_56 upper crust breccia fractured by coseismic, 2 pieces 23:19 Test sediment nature -sand 00:59 Fault scarp: POI AUTT7 01:14 AUTT 41 Fault scarp (small) 09:18 SBS_657_55 piece of lava slab at front of the flow 05:58 subparallel fractures 23:45 Fault scarp: SBSCOS01 -45 cm vertical displacement 01:09 Fault scarp: laser measure 01:26 AUTT 42 scarp ? 10 cm -09:25 off bottom, OTUS end 06:03 small scarp/fractures subparallel 23:55 Dejection cone POI: SBSCONE ,begin dejection cone 01:12 Fault scarp: AUTT8 light breccia and dejection cone, FPF 01:30 AUTT 43 Fault scarp 10:06 Victor at surface 06:17 continue exploration to N, nothing spectacular, highly sedimented rift 20170404 01:15 Fault scarp: laser measure at FPF, AUTT9 01:37 AUTT44 breccia and slump surface, collapse scar 10:33 Victor on deck 06:29 big scarp, massive, deformed but no fault plane. Laser measurement 00:12 Fault scarp: POI AUTT3 -Scarpment with 1 m dicplacement 01:29 Dejection cone: start OTUS survey 01:45 AUTT 45 RSD point -no rupture old fault plane 07:08 going through "fault" and 2 small mounts, parallel, broken volcanic crust 00:20 Fault scarp: ODEMAR 2013 Scarp AUTT4-FPA 01:37 Fault Scarp: AUTT10 arriving at FPG, breccia with blocks 02:06 AUTT 47 RSC point 07:20 end OTUS 00:53 Fault scarp: Sampling -SBS_653-01 (lost at ROV recovery) on FPA 01:41 Fault scarp: laser measure at FPG, AUTT11 02:10 thin lining coseismic at the base of the scarp 07:23 sampling volcanic crust that we follow for a while, AUTT11, SBS_658_57 01:27 Fault scarp sampling FPA/2013 scarp-SBS_653-02. 2 pieces -POI AUTT6 01:51 Fault Scarp: laser measure at FPH, AUTT12, breccia with fibers 02:33 AUTT 49 Fault plane sub vertical striations, old 07:43 start OTUS, going to N to fault trace 02:10 Fault scarp FPB, ~1 m displacement associated to coseismic slip 02:52 AUTT 50 RSB point 08:01 OTUS: modified white balance (auto -> preset) 02:20 Fault Scarp FPB 3D survey 02:07 Recent rockfall: AUTT13 02:55 Fault plane (polished ? "mirroir") 08:32 AUTT12 small scarp at bottom of slope, Laser measurement ~50cm, 02:51 Dejection cone CAB: Debut OTUS653-CAB 02:10 Fault scarp: difficult to identify 03:36 AUTT53 coseismic scarp about 30 cm SBS_658_058 limestone? a lot of blocks on sediments 03:59 End OTUS survey 02:19 Massive lava flow: AUTT14, SBS-654-013 03:41 AUTT54 RSA point, laser mesure: 20cm, breccia scarp 08:41 3D video, going to the NW to see if it continues, cracks above scarp 04:18 Transect over cumulative fault scarp for sampling 02:30 Massive lava flow: AUTT15, SBS-654-014 03:48 AUTT55, laser mesure: 20cm, rock talus, the scarp disapears 09:01 fracture= crack covered by sediments 04:37 SBS-653-003 -1074m 02:36 Fault scarp: FPI 04:16 AUTT56 cosismic scarp present; laser mesure (depth: 1034m), 09:04 coseismic scarp, laser measurement ~50cm 05:03 SBS-653-004 -1048m (ignimbrite-like) 02:40 Fault scarp: AUTT17, laser 1.40m coseismic displacement, vertical stria 04:44 AUTT57 Fault scarp: laser mesure: 20 cm 09:06 Laser measurement 05:20 SBS-653-005 -1022m Alternance breccias, blocks, layered levels 06:24 SBS-653-006 02:42 Vertical video mosaic for 3D reconstruction 02:44 Fault scarp: SBS-654-015, vertical striations, AUTT18 02:50 Fault scarp: laser measure (6x16cm), AUTT19 05:09 AUTT59 laser mesure of scarp: 40 cm, error in ROV nav 05:14 AUTT60 Fault scarp 05:24 AUTT61Cosismic scarp 2004 laser photo 09:08 smaller scarp covered by sediments, en-echelon structures Figure 3.12. ROV track for dive #657 (black), and sample locations (red stars with numbers) 09:09 Laser measurement ~60cm, very big blocks overlain on microbathymetry. 09:15 AUTT15 scarp, laser measurement ~45cm. We have to end the dive but scarp 06:42 SBS-653-007 02:50 Fault scarp: laser measure (>7x16cm), AUTT20 05:36 AUTT62 sampling ancient fault scarp: SBS_655_022 continues further to the NW 07:02 SBS-653-008 -934m 03:15 Fault scarp: near FPJ, laser measure, AUTT22 05:53 sample SBS_655_023 from fault plane (companion to SBS_655_022) 07:15 SBS-653-009 -934m 02:50 Fault scarp: laser measure, AUTT21 05:40 OTUS off 09:18 off bottom
	03:27 Fault scarp: near FPK, laser measure (7x16cm), AUTT23 05:58 second large clast sample added to SBS_655_023

track for dive #653 (white, and sample locations (red dots with numbers) overlain on microbathymetry. 09:51 Breccia, SBS-654-020 -958m 10:04 Breccia with smaller grains, SBS-654-021 -945m 10:13 End of dive Figure 3.9. ROV track for dive #654 (white, and sample locations (red dots with numbers) overlain on microbathymetry.

Figure 3.10. ROV track for dive #655 (white), and sample locations (red dots with numbers) overlain on microbathymetry and regional ship bathymetry. 06:10 SBS_656_039 looks like pillow, but very irregular; going up towards AG03 06:24 OTUS started 06:29 AUTT_168: squared cooling texture on top of small hill SBS_656_040 06:54 AUTT_169: border of crater 07:00 top of the hill near AG03: sample SBS_656_041 07:10 OTUS stop -start; going down to AG06 07:14 ropy lava 07:23 brecciated lava with cooling texture at base of the hill 07:28 AUTT_170: SBS_656_042 big piece of brecciated flat rock 07:44 possible vent, very breciated (top of some dome at 766m); going to AG06 08:03 base of AG06: 2 tries for breccia sampling but too hard 08:21 AUTT_171: transition between lava and breccia; SBS_656_043 bedded breccia, SBS_656_044 lava flow front with pillow structure 08:37 fractures in the lava flow 08:44 slope becomes very steep 09:03 following the fault, breccia; fault gets bigger towards NW 09:08 a fault plane dipping East 09:10 AUTT_173: small wall of breccia 09:11 ROV is leaving the sea floor 09:57 ROV at the surface 10:01 lest on board 10:32 ROV on board, end of dive 656 Figure 3.11. ROV track for dive #656 (black), and sample locations (stars with numbers) overlain on microbathymetry.

  ROV navigation data was post-processeed in May 2017, to obtain reference navigation files for each dive. All renavigated data are available in the Data Annex, folder '09_ROV_Navigation/Renavigation'.

	This folder contains
	a) a pdf file: 17_ 129_CR_SUBSAINTE_VICTOR.pdf, with the information on the re-
	processing carried out by GENAVIR.
	b) Re-processed navigation files
	Files with renavigated data for each dive are available as ascii text files in the Data
	Annex folder '09_ROV_Navigation/Renavigation' under:
	SUBSAINTE-VICTORXX -> SUBSAINTES-VICTOR-PLXX-mosaique.txt
	Where XX is the dive number (sequential starting from 01, corresponding to ROV
	dive #653).
	The renavigated files include time information, latitude, longitude and vehicle depth
	every 1 second, with the format below (example from SUBSAINTE-VICTOR-PL12-
	mosaique.txt, wrapped lines)
	Date	Heure Latitude	Longitude	Immersion	Cap	Pitch Roll	Easting_st
		Northing_s	Altitude_s	Standard_dev_Heading	Standard_dev_Pitch
		Standard_dev_Roll
	19/04/2017	23:31:00.459 15.73423752 -61.52357334 -557.326	107.97 0.25	-0.23
		1.072 1.07	0.151 0.017694	0.001417	0.001414
	19/04/2017	23:31:01.459 15.73423794 -61.52357246 -557.737	108.08 0.34	-0.15
		1.083 1.081 0.151 0.017693	0.001417	0.001414

SAMPLE POSITIONS SHOULD BE EXTRACTED FROM SBS_master_sample_table_FINAL_NAV.xls and reported in Table 4.1. Positions re- ported below in the rock sample descriptions are those recorded onboard and therefore do not correspond to the final, renavigated positions.

  table described immediately below. Shipboard positions that are reported in rock sample summaries (Section 4.2), or in individual rock sample descriptions in the Data folder (see immediately below) have not been modified to match the renavigated positions.All the sample information is summarized in a running Excel table that includes the sample number, UTC date and time, the depth, latitude and longitude of the ROV from available navigation onboard (estime), a lithological key, information on the fault nature or not of the sample, and the weight of each sample. This table, SBS_master_sample_table.xlsx can be found in the folder: 11_ROV_RockSamples Post-cruise, we have used the renavigated ROV files to update the final sampling positions. Under the file SBS_master_sample_table_FINAL_NAV.xls in this same folder, we have appended the columns with final navigation that provide the renavigated position if available, or the 'estime' position if no renavigation data is available for any given sample. This table also includes columns with both the renavigated and estime positions separately. Samples lacking any of these positions are indicated by NaN. FINAL After a VICTOR dive, and when the VICTOR is back on deck, the rock sampling boxes are recovered from the basket and the samples are identified using the labels and the photos if necessary, and numbered. The rocks are cut, described and sampled for further studies. The archive is stored in separate boxes. The information of archive boxes and their content is available in the Excel table file SBS_caisses.xlsx, available under the folder 11_ROV_RockSamples.

Table 4

 4 Note -positions given here are those recorded onboard. Final sample positions using renavigated data are reported in table 4.1, and are also available in the final file SBS_master_sample_table_FINAL_NAV.xls within Data Annex folder 11_ROV_RockSamples.

				sandstone
	SBS661_097	20170414	11:03	lava	15	40.63394	27.76153	-509.85
	SBS661_098	20170414	12:17	lava	15	40.54219	27.88727	-327.51
	SBS661_099	20170414	12:36	lava	15	40.54154	27.89086	-323.68
				volcaniclastic
	SBS661_100	20170414	13:23	breccia	15	40.47286	27.93601	-257.89
	SBS661_101	20170414	13:42	lava	15	40.49933	27.92749	-260.87
	SBS661_102	20170414	14:11	lava	15	40.51823	27.93173	-270.56
	SBS661_103	20170414	14:49	lava	15	40.54382	27.96379	-250.25
	SBS661_104	20170414	15:18	lava	15	40.56386	27.95948	-266.15
	SBS661_105	20170414	16:29	lava	15	40.62532	27.94429	-343.32
	SBS661_106	20170414	18:00	sponge	15	40.54668	28.07323	-153.27
	SBS661_107	20170414	21:47	lava	15	40.44881	28.32570	-307.85
	SBS661_108	20170414	22:03	lava	15	40.45034	28.32683	-308.18
	SBS661_109	20170414	22:46	lava	15	40.57148	28.33511	-334.46
	SBS661_110	20170414	22:54	lava	15	40.58950	28.36464	-328.28
	SBS661_111	20170415	00:09	lava	15	40.67886	28.61323	-436.83
	SBS661_112	20170415	00:50	lava	15	40.63129	28.54786	-337.55
	SBS661_113	20170415	01:59	lava	15	40.53925	28.55592	-258.12
	SBS661_114	20170415	02:56	lava	15	40.49748	28.62513	-267.14
	SBS661_115	20170415	03:33	lava	15	40.50068	28.62615	-271.77
	SBS661_116	20170415	04:33	lava	15	40.46160	28.62241	-221.96
	SBS661_117	20170415	06:16	lava	15	40.62085	28.86435	-477.96
	SBS661_118	20170415	06:36	lava	15	40.62722	28.88661	-505.17
	SBS661_119	20170415	06:50	lava	15	40.62971	28.90552	-536.34
	SBS661_120	20170415	07:12	lava	15	40.66674	28.96426	-637.5
	SBS661_121	20170415	08:08	lava	15	40.83413	28.91869	-743.07
	SBS661_122	20170415	08:22	lava	15	40.85108	28.88518	-748.04
				sedimentary
	SBS662_123	20170416	00.37	sandstone	15	42.09743	29.19440	1183.37
				sedimentary
	SBS662_124	20170416	01:05	sandstone	15	42.07429	29.17499	1177.2
	SBS662_125	20170416	01:33	lava	15	42.06143	29.20749	1214.12
	SBS662_126	20170416	01:59	lava	15	42.03137	29.23319	1180.53
	SBS662_127	20170416	03:25	lava	15	41.80274	29.54023	1236.18
				Volcaniclastic
	SBS662_128	20170416	04:25	breccia	15	41.74368	29.61811	1225.83
	SBS662_129	20170416	06:28	lava	15	41.47354	29.73740	-1261.92
				pyroclastic
	SBS662_130	20170416	08:49	deposit	15	41.86290	30.22818	-1230.2
				pyroclastic
	SBS662_131	20170416	08:52	deposit	15	41.86279	30.22912	-1229.2
	SBS662_132	20170416	08:57	lava	15	41.86309	30.22864	-1229.15
	SBS662_133	20170416	09:08	lava	15	41.91451	30.29825	-1203
				Volcaniclastic
	SBS662_134	20170416	10:03	breccia	15	41.94167	30.36140	-1185.47
	SBS662_135	20170416	11:37	lava	15	42.12863	30.24203	-1180.04
	SBS662_136	20170416	12:03	lava	15	42.18431	30.23232	-1129.66
	SBS662_137	20170416	13:18	lava	15	42.32121	30.30526	1091.81
	SBS662_138	20170416	15:18:00	lava	15	42.31602	30.45200	1089.14
	SBS662_139	20170416	16:13:00	lava	15	42.38400	30.34865	1032.03
	SBS662_140	20170416	16:53:00	lava	15	42.50953	30.38167	1084.45
	SBS662_141	20170416	18:47:00	lava	15	42.57891	30.58150	1001.72
	SBS662_142	20170416	21:06:00	lava	15	42.67927	30.78148	912.12
	SBS662_143	20170416	23:53:00	lava	15	43.03434	30.99614	714.33
				volcaniclastic
	SBS662_144	20170417	00:14:00	breccia	15	43.06886	31.00094	696.7
				volcaniclastic
	SBS662_145	20170417	02:14:00	breccia	15	43.30108	31.41242	617
				volcaniclastic
	SBS662_146	20170417	04:41:00	breccia	15	43.37544	31.47440	610.43
	SBS662_147	20170417	05:19	lava	15	43.57928	31.47081	592.28
	SBS662_148	20170417	05:39	lava	15	43.47358	31.44651	569.64
	SBS662_149	20170417	05:46	lava	15	43.37745	31.45859	569.8
	SBS662_150	20170417	07:03	lava	15	44.40760	31.29770	525.59
	SBS662_151	20170417	08:43	lava	15	44.88395	31.28722	707.79
	SBS662_152	20170417	09:10	lava	15	44.92180	31.27650	679.44
	SBS662_153	20170417	01:35	iron concretion	15	43.16893	31.22008	612.4

.1 reports the list of samples with the renavigated positions, as a partial extraction of the file SBS_master_sample_table_FINAL_NAV.xls.

on the South part of the Roseau Fault and base of the Roseau Volcano

  Note -positions given here are those recorded onboard. Final sample positions using renavigated data are reported in table 4.1, and are also available in the final file SBS_master_sample_table_FINAL_NAV.xls within Data Annex folder 11_ROV_RockSamples.Note -positions given here are those recorded onboard. Final sample positions using renavigated data are reported in table 4.1, and are also available in the final file SBS_master_sample_table_FINAL_NAV.xls within Data Annex folder 11_ROV_RockSamples.

	4.2.2 ROV Dive #655 -Roseau Fault S SBS655_025 06/04/2017 :28 15º44,9063 -61º33,9186 1052.7 SBS655_030 06/04/2017 :39 15°44.5290 -61°34.3626 1094 SBS656_037 08/04/2017 05 :15 15°43.9419 -61°24.4394 811 SBS656_042 08/04/2017 07:29 15°43.9656 -61°24.5459 771.3 4.2.5 ROV Dive #657 -Agoucha	Just behind fault plane Fault plane at limit with 2004 co-seismic displace-ment sur-face SW flank of Agucha A Summit area Agucha B	Volcani-clastic breccia Sand-stone Sedimen-tary brec-cia Lava	11x5x6 2 pieces 8x5x2, 5x1x4 25x14x3 38x21x1 3	0.34 0.150 + 0.06=0.2 10 1.14 11.025	Friable ma-trix,brownish polylithologic volcanic clasts White partly indurated sandstone fault striations, hard fied andesite crust calcareous matrix, shell fragments, coral roots, burrows Lithi-Polygonal joints alteration halo crysts (plagio), Massive very rich in pheno-
	Sample name SBS655_026 SBS655_031 SBS656_038 SBS656_043	Date 06/04/2017 :45 15º44,9269 -61º34,9356 1062.6 Time UTC Lat N long W Depth (m) 06/04/2017 :36 15°44.0192 -61°33.8345 1131.5 08/04/2017 05 :55 15°44.0103 -61°24.4420 734 08/04/2017 08:25 15°43.9316 -61°24.7089 751.8	Location Behind fault plane in damage zone Old fault surface with manganese crust Agucha A Summit area Agucha C ; summit area	Type Lava Volcani-clastic breccia Lava Calcare-ous sand-stone	Size (cm) 13x8x5 13x2x1 8x5x2 26x23x7	Weight (kg) 0.7 0.9 0.091 0.75	Comments Rounded block gray, vesicle and crystal rich andesite Polylithologic centimetric clasts Yellowish, Similar to altered, abun-dant vacuoles Plagioclase and px phenocrysts, SBS_656_037, coral stems holes on sur-face paleo andesite or basalt ? burrows casts	Bottom photo	Sample photo
	SBS655_022 SBS655_027 SBS655_032 SBS656_039 SBS656_044	06/04/2017 05 :35 15º44,8835 -61º34,8969 1057.8 06/04/2017 :05 15º44,8133 -61º34,7271 1079,2 07/04/2017 :35 15°43.6059 -61°33.5643 1064.9 08/04/2017 06 :11 15°44.0129 -61°24.4398 721 08/04/2017 08:29 15°43.9343 -61°24.7096 750.8	On old fault plane Bedded sedimentary units on step/terrace in the slope Sedimentary bedded unit SW flank of Agucha A Agucha C, summit area	Volcani-clastic breccia sand-stone Volcani-clastic breccia Lava Lava	3 pieces 8x5x1 ; 6x4x5 ; 7x5x3 & small 7x4x2 + fragments 6x4x7; 5x4; 5x5 plus small fragments 2 pc : 6.5x4x4. 5 2 pc : 11x8x5 14x12x4 11x3x7 fragments	0.580 0.35 0.612 0.236 0.873	micro vesicular one rounded andesite clast Contains shell fragments & black volcanic minerals Layered brec-cia and fine grained sandy layer fine grained, looks more recent than 038 flow front pa-hoehoe, ropy bulbous, fluid andesite basalt ?
	SBS655_023 SBS655_028 SBS655_033 SBS656_040	06/04/2017 05 :56 15º44,8835 -61º34,8969 1057.8 06/04/2017 :26 15º44,8141 -61º34,6492 1115,1 07/04/2017 :28 15°44,0229 -61°33.0598 976 08/04/2017 06 :34 15°44.0175 -61°24.4302 709.2	On old fault plane Bedded sedimentary units on step/terrace in the slope small fault to the NE of the southern Roseau fault, cutting the volcano the Roseau SW edge of Agucha A, summit area	Volcani-clastic breccia Volcani-clastic breccia Lava Lava	2 pieces 17x11x5 9x5x4 12x6x9, 3 small centimet-ric pieces 30x13x16 10x11x6	1.070 0.180 1.05 (total: 1.25) 3.1 0.935	Friable matrix, from debris flow ? Polylithologic volcanic altered clasts , from debris flow ? Very dense, phenocrysts brite ? welded ignim-highly altered, silica-rich (dacite ?) -Lava flow Pretty fresh Andesite ?
	SBS655_024 SBS655_029 SBS656_041	06/04/2017 05 :57 15º44.8911 -61º34.8977 1058.3 06/04/2017 :39 15°44.5290 -61°34.3626 1094 08/04/2017 07:04 15°44.0214 -61°24.4229 707.7	On old fault plane Old fault scarp cross-cutting vol-canic brec-Agucha A summit area cia	Volcani-clastic breccia Volcani-clastic breccia Lava	8x3x6 5x4x2 + small 16x12x1 0 fragments	0.25 0.190 2.373	Friable matrix, from debris flow ? Massive no Polylithologic vesicles, very volcanic altered clasts, altera-rich in pheno-crysts (plagio), tion aureole alteration halo Polygonal joints

DIVE SBS655 DIVE SBS657

on Agucha volcanoes and fault zone

  Note -positions given here are those recorded onboard. Final sample positions using renavigated data are reported in table 4.1, and are also available in the final file SBS_master_sample_table_FINAL_NAV.xls within Data Annex folder 11_ROV_RockSamples.

	SBS657_048 SBS657_053 SBS659_062 11/04/2017 03:46 15°45.0378 61°28.5289 633 09/04/2017 01h25 15°43.7597 -61°24.6753 878,0 09/04/2017 08h17 15°44.4128 -61°25.0025 829.5 southern base of base of Agoucha complex, south of Agoucha C Pahoehoe lava flow Flat area between Agucha D and J Fault scarp lava flow at central dome SBS659_067 11/04/2017 06:15 15°45,1398 61°28,8302 715 in the crater wall units at the NE SBS659_072 11/04/2017 17:31 15°45.1431 61°28.5524 666 Crawen crater dome, base of the northern slope SBS659_077 11/04/2017 20:04 15°45.0880 61°28.5582 588 Crawen crater dome, close to summit 4.2.8 ROV Dive #660 -Crawen	lava Sedi-mentary breccia Lava lava Lava 22x15x0 13x8x10 24x9x5 9x6x7 0,350 1,080 0,880 Idem _060 relatively fresh matrix, highly crystal-rich, altered pheno-crysts, with amphibole Similar to _052 at outcrop scale 3 pc : 19x11x 4; 20x19x 15; 10x8x9 9.18 Abundant & Abundant & sampled in the bedded explosion volcanic ? Dacite ? the tuff cone glass, Dacite less altered breccia from 7 3.634 large amphi-bole 1 cm , quartz ? greenish ocre Lava grayish glass, 0 2.78 quartz ? 25x15x1 large amphi-bole 1 cm ,
	southern	breadcrust Abundant & Abundant &
	Sample name SBS657_049 SBS657_054 SBS659_063 11/04/2017 04:06 15°45.0366 61°28.5280 635 Date Time UTC Lat N long W 09/04/2017 02h04 15°43.8068 -61°24.7192 849,7 Depth (m) 09/04/2017 09h20 15°44.6006 -61°24.9932 786 Lava in fracture Location base Agou-cha complex, south Agou-cha C Pa-hoehoe lava flow Lava flow -Soiuthern flank of Agoucha J near the fault cross-cutting the central dome, southern flank SBS659_068 11/04/2017 06:59 15°45,2276 61°28,7263 722 Base of the Crawen north crater wall SBS659_073 11/04/2017 18:17 15°45.1103 61°28.5023 652 Crawen crater dome East base of the SBS659_078 11/04/2017 20:14 15°45.0847 61°28.5340 585 Crawen crater dome, close to summit Eastern slope	Type volcani-clastic breccia Lava Lava 14x6x5 0,510 Size (cm) Weight (kg) 18x20x30 3,8 8x9x7 0,820 Lava 7x16x2. 5 8x7x4 0.9 lava bomb Comments autobreccia Very altered (brownish) bulb pahoehoe lava flow with de-formed layers (sag) in upper tuff large amphi-large amphi-Lava 26x25x2 3 4.7 total: 20 kg bole 1 cm , quartz ? greenish ocre Lava bole 1 cm , 33x21x1 7.78 quartz ? 0 yellowish glass, Dacite glass, 11x8x9 cone layers -? Dacite ?	Bottom photo	Sample photo
	SBS657_045 SBS657_046 SBS657_047 SBS657_051 SBS657_052 SBS659_066 11/04/2017 05:39 15°45,0598 61°45,0598 713 08/04/2017 23:21 15°43.7030 -61°24.6299 903.1 08/04/2017 23:45 15°43.7020 -61°24.6303 903.0 09/04/2017 00h32 15°43.7344 -61°24.6743 888.9 09/04/2017 06h18 15°44.2981 -61° 24.9394 828.5 09/04/2017 06h59 15°44.3142 -61°24.9469 829.7 Inside crater, base of Agoucha complex, south of Agoucha C, near fissure complex, south of Agoucha C Small vol-canic vent near the fissure base of Agoucha complex, south of Agoucha C Pahoehoe northern base of Agucha D base of Agucha D on top of lava flow along fault scarp layered units (bottom) SBS659_071 11/04/2017 09:15 15°45,4965 61°28,7674 595 Crawen tuff cone North wall of the caldera, top SBS659_076 11/04/2017 19:59 15°45,0903 61°28,5253 592 Crawen crater central dome northern SBS659_065 11/04/2017 04:36 15°45.0380 61°28.5417 632 Near _064 (bot-tom of crater) SBS659_070 11/04/2017 09:15 15°45199 61°28.7667 602 Crawen tuff cone crater mid-slope, North wall SBS659_075 11/04/2017 19:38 15°45.0931 61°28.5256 594 Crawen crater dome, close to summit Agoucha base of SBS657_050 09/04/2017 03h16 15°43.9843 -61°24.8794 747.9 Southern base of Agucha D Brecciated lava flow in eruptive fissure SBS657_055 09/04/2017 09h19 15°44.6006 -61°24.9904 785.7 Soiuthern flank of Agoucha J Front of the lava flow SBS659_064 11/04/2017 04:32 15°45.0383 61°28.5416 632 Crawen volcano. Lava dome front (bottom of the crater), southern flank of the central dome SBS659_069 11/04/2017 07:53 15°45,3407 61°28.7110 664 Craven North crater wall, lower slore SBS659_074 11/04/2017 18:35 15°45.0830 61°28.4824 655 Crawen crater dome, East base of the central dome SBS659_079 11/04/2017 20:31 15°45.0788 61°28.5460 577 Crawen crater dome, close to summit	Volcani-clastic breccia lava lava car-bonate-breccia Calca-reous sand Sand-stone (pyro-clas-tic?) Lava 27x14x2 4x2x0,5 3,5 x 2 2,5x3 15x12x8 15x12x8 17x11x5 3 main pc: 7x6x5 6x4x3 8x8x5 20x17x 4 1.45 1,290 0,035 0,545 0,920 Andesite Very old look-ing, brown Altered, brown Silicified matrix Autobrecciation of pahoehoe lava Very altered (brownish) bulb pahoehoe lava flow corals and shells frag-ments 0,520 semi indu-rated to friable bio-clastic sandstone fresh ? 0 7.3 cone ballistic glass, Dacite No amphi-bole tuff Lava greenish ocre 5 4.01 quartz ? 20x20x1 bole 1 cm, Lava 9x8x8 0.54 conchoidal smooth fracture, entirely devitrified Lava or Welded pyro-clastic large amphi-brite ?) ignimbrite ? Abundant & (ignim-29x25x0 6 7.3 sheared silica folitation, welded ? texture ? glass, Dacite flame/fiame Lava greenish ocre 0 1.867 quartz ? 17x13x1 bole 1 cm , large amphi-lava 20x30x21 8,55 Very fresh massive rock welded lava flow Few plagio and minor px phe-nocrysts Abundant & surge ? Lava 17x10x4 0,520 Autobrecciated lava flow Lava 12x12x 8 1.2 grey, vitric, very crystal rich (plg, px) highly al-tered Pyro-clastic deposit 20x15x1 0 9x6x4 2.45 pumice clasts bioclasts sandy wavy laminated pyroclastic Lava 26x13x1 2 30x15x1 4 2.950 5.260 =8.21 Abundant & Abundant & large amphi-bole 1 cm , quartz ? greenish ocre large amphi-Lava 18x10x0 5 bole, quartz 0.78 ? yellowish glass, glass, Dacite ? Dacite ?
	lava flow

DIVE SBS660 on Cassave dome, Crawen crater, Crawen fault

  Note -positions given here are those recorded onboard. Final sample positions using renavigated data are reported in table 4.1, and are also available in the final file SBS_master_sample_table_FINAL_NAV.xls within Data Annex folder 11_ROV_RockSamples.Note -positions given here are those recorded onboard. Final sample positions using renavigated data are reported in table 4.1, and are also available in the final file SBS_master_sample_table_FINAL_NAV.xls within Data Annex folder 11_ROV_RockSamples.Note -positions given here are those recorded onboard. Final sample positions using renavigated data are reported in table 4.1, and are also available in the final file SBS_master_sample_table_FINAL_NAV.xls within Data Annex folder 11_ROV_RockSamples.

	Sample name SBS660_080 12/04/2017 14:56 15°44,2297 61°29,3702 Date Time UTC Lat N long W SBS660_081 12/04/2017 16:29 15°44.3604 61°29.3037 SBS660_082 12/04/2017 16:44 15°44,3496 61°29,3203 SBS660_083 12/04/2017 17:11 15°44,3695 61°29,3330 855 Depth (m) 904 857 859 SBS660_084 12/04/2017 17:39 15°44,3960 61°29,3516 862 SBS660_085 12/04/2017 15:47 15°44,3072 61°29,3615 893 SBS660_086 12/04/2017 21:13 15°44,4455 61°29,2250 863 SBS660_087 12/04/2017 22:31 15°44,2077 61°29,0510 894 SBS660_088 13/04/2017 07:01 15°45,3118 61°28,3857 635 SBS660_089 13/04/2017 09:24 15°46,0850 61°28,6861 638 SBS660_090 13/04/2017 10:49 15°46,1773 61°28,7520 628 SBS660_091 13/04/2017 11:26 15°46,1939 61°28,8494 646 SBS660_092 13/04/2017 11:46 15°46,1797 61°28,8031 631 SBS660_093 13/04/2017 13:07 15°46,1730 61°28,7469 627 SBS660_094 13/04/2017 13:45 15°46,2606 61°28,8149 630 SBS660_095 13/04/2017 14:02 15°46,2890 61°28,8386 621 SBS660_096 13/04/2017 14:25 15°46,2993 61°28,8606 627 4.2.9 ROV Dive #661 -Colibri DIVE SBS661 on Colibri Volcano Sample name Date Time UTC Lat N long W Depth (m) Location Location Flat area, SW of Cassave dome SW slope of Cassa-ve dome Cassave dome Cassave dome Cassave dome Cassave dome Fault East of Cassave, scarp Fault East of Cassave, base of the scarp Crawen fault, at the caldeira NE edge Crawen fault, North of Crawen volcanoe Fault plane Top of Crawen fault, Black material filling fissure network Crawen fault, North of Crawen volcano Crawen fault, North of Crawen volcano Top of Crawen fault, Black material filling fissure network Base of fault plane, Crawen fault Crawen fault, fault plane Crawen fault, Fault plane SBS661_097 14/04/2017 11:03 15°40,6338 61°27,7622 509 East of Eastern Colibri Dome (close to the base) SBS661_098 14/04/2017 12:17 15°40,5429 61°27,8872 326 East slope of Eastern Colibri Dome, edge of a major col-lapse structure SBS661_099 14/04/2017 12:36 15°40,6689 61°28,4605 374 East slope of Eastern Colibri Dome, edge of a major col-lapse structure fault east Souffleur Sandstone Type or pyroclas-tic ? Lava Lava Lava Lava Lava Volcani-c lastic brec-cia Lava Volcani-clastic breccia Volcanic breccia Iron concre-tion ? Iron concre-tion Iron concre-tion Iron concre-tion Calcareous breccia Sedimentary sandstone sedimentary sandstone Type Size (cm) Size (cm) 26x16x6 25x16x6 30x32x17 20x35x55 30.92 Weight (kg) 2 4.85 10.9 38x23x12 9.25 28x13x10 2.2 20x10x8 3.2 10x10x7 0.73 67x54x17 35 12x8x4 and small-er frag-ments 0.675 16x9x5 0.66 32x25x10 9.1 40x28x12 9.85 13x27x6 2.7 13x6x9 7x7x5 8x3x5 8x5x3 1.88 12x6x3 6.5x3x4 0.32 34x15x5.5 2.44 Weight (kg) Comments Comments bedded bio-clastic, al-tered volcan-ic clasts, pyroclastic distal tuff ring/tuff cone from Crawen ? crystal-rich, finely vesicu-lar, alteration halo, basaltic andesite ? crystal-rich, finely vesicu-lar, alteration halo, basaltic andesite ? crystal-rich, finely vesicu-lar, mostly fresh, basal-tic andesite ? very altered yellowish glass matrix -from side of dome dome talus lava + plu-tonic xenolith sandstone laminated Crawen pyroclastic surges Coarse grained vol-canoclastic sandstone, well consoli-dated Andesite ? Lava is aal-tered (pink-ish) Polygenic, with rounded blocks, al-tered Possibly crushed in the fault Gouge ? Black con-cretion, iron oxyde ? Intermixed with beige sediment Iron oxyde ? Similar to 090 Mixed with sedimentary sandstone Iron oxyde ? Two slabs, attached Thick layer of sandstone Nodular-like growth of iron ( ?) minerals Some inter-stitial beige sediment Irregular fragments of a porous breccia Travertine fragments ? Lava clasts Black thin slab with an angu-lar fragment of crossbed-ded sandstone attached Slab of yel-lowish sedi-mentary sandstone with black fragments of volcanic rocks Lava 30x12x7 17x7x7 12x7x6 13x7x4 3,15 2,95 0,7 0,45 Massive dense lava. Highly phyric dacite. Moderately-slightly altered Lava 13x8x7 0,7 Small frag-ment of mas-sive lava. Highly phyric Dacite with bread crust texture. Lava 16x11x8 1,29 Fine grained, unaltered aphyric-aphanitic lava with swirly texture and 4 riped up clasts of older co-ing lava flow clasts from underly-breccia with some bio-genetic lava SBS661_105 14/04/2017 16:29 15°40,6253 61°27,9455 343 Eastern Colibri Dome; lava flow from within the east (collapse ?) structure lava 26x17x13 33x17x10 27x12x11 and 15 smaller ~40 Highly porphy-ritic dark grey weakly to non altered mas-sive lava SBS661_106 14/04/2017 18:00 15°40,5402 61°28,0587 153 Eastern Colibri volcanoe, edge of a major collapse struc-ture Sponge 8x4x3 4x2x2 0.050 Biological sample, not kept SBS661_107 14/04/2017 21:47 15°40,4489 61°28,3260 307 Western Colibri Dome; base, east side lava 6x5x4 0.155 Porphyritic dark gray unaltered lava rich in crystals SBS661_108 14/04/2017 22:03 15°40,4573 61°28,3241 307 Western Colibri Dome; base, east side lava 17x10x7 1.15 Breadcrusted lava, same as 107 SBS661_109 14/04/2017 22:46 15°40,5714 61°38,3352 334 Western Colibri Dome; base, north-east side lava 16x13x8 2.3 Breadcrusted clasts Same as 108 SBS661_120 15/04/2017 07:12 15°40,6666 61°28,9648 638 Western Colibri Dome; NE side, towards the base lava 21x13x8.5 1.8 Same as 098, but much more altered SBS661_121 15/04/2017 08:08 15°40,8330 61°28,9178 742 Western Colibri Dome; base of NE side; at the front of mas-sive lava flow lava 12x10x4 0.7 Same as 098, a bit more altered SBS661_122 15/04/2017 08:22 15°40,9493 61°28,8862 747 Western Colibri Dome; NE side, outer slope lava 12x10x7 0.7 Very irregular clast with porosity from relict pumi-ceous texture and cavities. 4.2.10 ROV Dive #662 -Rosseau Volcano DIVE SBS662 on Roseau Volcano Sample name Date Time UTC Lat N long W Dept h (m) Location Type Size (cm) Weigh t (kg) Comments Bottom photo Bottom photo Bottom photo SBS662_123 2017-04-16 00:37 15º42.0987 61º29.1932 1183 East of Colibri valley Sedimentary sandstone 8x5x7 + 2 small 0.435 Yellowish color, milli-metric shells, black minerals and some qurtz SBS662_124 2017-04-16 01:05 15º42.0743 61º29.1755 1177 East of Colibri valley Sedimentary sandstone 5x4x2.5 + 3 small 0.05 Yellowish color, milli-metric shells, black minerals and some qurtz SBS662_125 2017-04-16 01:33 15º42.0612 61º29.2076 1214 Small crater NQ of Colibri volcanoe Lava 17x20x17 8.3 Massive dense lava. Dark grey with very glassy matrix and abundant plagioclase minerals. Vesicles also present SBS662_126 2017-04-16 01:59 15º42.0316 61º29.2333 1180 Along a fault scarp, NW of Cobri volc., lava 27x19x16 10.5 Massive lava lying onto pumice rich volcano-clastic deposit with coarse grain matrix including quartz grains, elongated, sub-SBS662_131 2017-04-16 08:52 15º41.863 61º30.2297 1229 Southwest of Carrata hills, along the Colibri fault Pyroclastic deposit 21x16x17 2.0 Massive pyroclastic deposit. Light-grey, glassy to fibrous matrix with amphiboles and quartz SBS662_136 2017-04-16 12:03 15º42.1847 61º30.2315 1128 Northern scarp of Carrata fault. Lava 16x9x8 1 Massive prismatic intensively altered lava flow. Brown matrix. Different stages of alteration SBS662_141 2017-04-16 18:47 15º42.5784 61º30.5802 1001 Carrata fault scarp Massive lava flow at the base of the fault lava 20x17x11 6 Massive lava, medium grained, altered Small abundant plagio-clase phenocrysts and rare ferromagnesian SBS662_150 2017-04-17 07:03 15º44.4080 61º31.2985 526 top of main dome at the sum-mit of Roseau volcano lava 30x15x11 4.5 Dense reddish massive lava, fine grained matrix, lots of amphi-bole, plagioclase autoclatss SBS664_167 20/04/17 03 :07 15°44.5039 -61°31.3664 559 Roseau volcano, summit area, central dome lava : 5,5 x 5,5 x 2,5 0.06 Fine-grained lava, micro-phenocrysts of plagio SBS664_172 20/04/17 06:50 15°45.0545 -61°31.2199 694m Fault scarp area, North of Roseau volcano Carbona-ceous breccia 5x4x4 0.1 tuffaceous carbonate concretion SBS664_177 20/04/17 11 :25 15°44.8561 -61°31.0330 755m Fault scarp area, North of Roseau volcano, towards the volcano-clastic breccia 36x28x21 19.5 Large block of polygenic breccia SBS664_182 20/04/17 23:05 -61°31.8474 15°46.4192 603.5 Hummock (?) Same lava as 4.2.13 ROV Dive #665 -Souffleur Fault Black iron concre-Close to the summit of Coche volca-no lava 16x12x6 + 13x9x1 10.2 Exactly same lava as SSB_664_179 SBS664_187 21/04/17 04:37 -61°32.293 15°46.5157 785 at the end of the NE scarp of Coche volcano lava 35x13x12 5.3 SBS_664_183, 182, 179, 185 SBS665_195 22/04/2017 7 :37 15°46.7176 -61°28.2464 589 Base of souffleur fault scarp tion enclosing Iron ( ?) 68x33x15 28,500 sedimentary clasts, concretion with late hydraulic and 186. More altered facturing ? Small xenolith ? East euhedral amphiboles. SBS662_127 2017-04-16 03:25 15º41.8028 61º29.5401 1236 W of Colibri volc. Lava 19x16x14 4.9 Very dark massive lava with glassy matrix SBS662_128 2017-04-16 04:25 15º41.7437 61º29.6180 1226 Southern most Carrato cone volcanoclas-tic breccia 16x11x11 1.9 Massive lava bloc lying onto a volcanoclastic deposit including lava scoria, volcanic lithics within a coarse matrix SBS662_129 2017-04-16 06:28 15º41.4720 61º29.7378 1262 Base of the south-ern most Colibri fault scarp Lava 16x15x9 10x9x8 1.1 Massive lava, inten-sively oxidized. Red matrix, many vacuoles, dark miner-als SBS662_130 2017-04-16 08:49 15º41.8634 61º30.2287 1230 Southwest of Carrata hills, along the Colibri-fault Pyroclastic deposit fragments 0.187 Grey pumices. Few cm large. Small (mm size) and large amphibole phenocrysts (up to 1 cm) -pumice fallout SBS662_132 2017-04-16 08:57 15º41.8633 61º30.2289 1229 Colibri fault scarp. Lava 21x15x12 5.5 Massive lava, prismatic block. 1cm wide weathering front. In the center, dark grey lava. Vesicles present. SBS662_133 2017-04-16 09:08 15º41.9150 61º30.2979 1203 Colibri fault scarp. Lava 22x15x13 4.2 Large blocks of mas-sive altered lava. Brown matrix inten-sively weathered. SBS662_134 2017-04-16 10:03 15º41.9423 61º30.3620 1185 Colibri fault scarp. Volcanoclastic breccia 9x6x8 0.4 Intensively altered. Orange matrix includ-ing small lithics of various colors SBS662_135 2017-04-16 11:37 15º42.1285 61º30.2427 1179 Northern scarp of Carrata fault. Lava 29x11x13 6.8 Massive prismatic intensively altered lava flow Brown matrix. SBS662_137 2017-04-16 13:18 15º42.3211 61º30.3054 1092 Northern Carrata cone lava 21x17x8 2.3 Massive lava with flow banding Dark lava slightly weathered, with fine grained matrix. SBS662_138 2017-04-16 15:18 15º42.3159 61º30.4520 1089 Carrata Hills lava 55x16x13 8.3 Bulbous lava with fluidal texture Fine grained, some ferromagnesian phe-nocrysts Olivine bearing bas-alt ? ' SBS662_139 2017-04-16 16:13 15º42.3836 61º30.3491 1031 Northern Carrata cone Lava 10x9x9 1.5 Autobrecciated lava flow Possibly olivine and px phenocrysts Very abundant tiny plagioclase Highly crystallized groundmass SBS662_140 2017-04-16 16:53 15º42.5098 61º30.3817 1085 Carrata fault scarp lava 43x17x14 8.7 Massive lava, altered Plagioclase and ferro-magnesian pheno-crysts vesicles SBS662_142 2017-04-16 21:06 15º42.6769 61º30.7808 912 Carrata scarp lava 30x25x30 35 columnar massive lava, fresh in the center Plagioclase pheno-crysts and olivine microphenocrysts, vesicles SBS662_143 2017-04-16 23:53 15º43.0343 61º30.9961 714 Roseau volcano, base of SSE flanc Lava 10x10x8 0.5 Autobrec-ciated lava flow . Reddish pink very altered highly phyric rock with large plagio Streched vitric fiame welded ignimbrite SBS662_144 2017-04-17 00:14 15º43.0689 61º31.0009 697 Roseau volcano, base of SSE flanc Volcaniclastic breccia 9x9x4 0.4 Volcanic breccia rich, in crystals, volcanic fragments, clast sup-ported, matrix, silici-fied SBS662_153 2017-04-17 01:35 15º43.1688 61º31.2208 612 Roseau volcanoe, going up the SSE flank Iron concretion 3 pieces 9x4x2 5x2x4 0.125 Possibly iron oxyde filling cracks, precipi-tated from fluid SBS662_151 2017-04-17 08:43 15°44.8840 61°31.2870 707 N Roseau volcano, along the E-W trend-ing N Roseau fault scarp lava 16x11x10 1.35 Dense lava, medium grain matrix, pheno-crysts (ferromagnesian altered) Alteration front SBS662_152 2017-04-17 09:10 15°44.9218 61°31.2757 679 N Roseau volcano, along the E-W trend-ing N Roseau fault scarp lava 11x9x5 0.7 Massive lava flow ; Massive greensish lava intruded into wet breccia of a tuff cone Altered amphbole SBS662_153 Misnum-bered See after 144 1 :35 SBS664_168 20/04/17 03 :30 15°44.4889 -61°31.3411 546 Roseau volcano, summit area, central dome Carbona-ceous breccia 9x8x8 0.48 Tuffaceous carbonate concretion SBS664_169 20/04/17 04 :32 15°44.3956 -61°31.3645 497 Roseau volcano, summit area, central dome. Lava 50x37x18 38.25 Outer fluidal slab of pohoehoe lava flow SBS664_170 20/04/17 05 :02 15°44.4768 -61°31.2858 555 Roseau volcano, summit area, central dome. lava 47x38x17,5 47 Prismatic, highly phyric massive lava, purple colour SBS664_171 20/04/17 06:49 15°45.0086 -61°31.2463 688m Fault scarp area, North of Roseau volcano lava 40x30x15 12.25 Porphyric massive lava. Abundant plagioclase phenocrysts SBS664_173 20/04/17 08 :21 15°44.9440 -61°31.3601 704m Fault scarp North of Roseau volcano lava 23x17x12 4.28 subangular block of mas-sive lava, probably piece SBS664_178 20/04/17 12:16 -61°31.3813 15°45.0995 698 Fault scarp area, North of Roseau volcano Carbona-ceous breccia 11x6x5 0.3 Tuffaceous carbonate concretion SBS664_183 20/04/17 23:15 -61°31.8505 15°46.4414 596 Close to the summit of Coche volca-no lava 50x43x24 37.74 Same lava as SBS_664_178/ 182 but more grey and less altered SBS664_188 21/04/17 5:50 -61°32.6327 15°46.4158 823 Along the main fault scarp, S side of the can-yon, E of lava 26x17x17 7.6 Same lava as SBS_664_183, 182, 179, 185 and 186. Very fine grained DIVE SBS665 on Souffleur fault Sample name Date Time UTC Lat N long W Depth (m) Location Type Size (cm) Weight (kg) Comments Bottom photo Sample photo Sample photo Sample photo SBS665_196 22/04/2017 8 :28 15°46.6769 -61°28.1745 564 mid-slope of Souffleur fault scarp sedimen-tary sil-stone sedimentary rock, 13x8x5 and 0,800 well consolidated 10x9x3,5 Cross-stratified Sample photo laminations Coche volca-of a breccia SBS664_174 20/04/17 09 :45 15°44.9190 -61°31.2626 680m Fault scarp area, North of Roseau volcano lava 25x18x13 4.5 fluid lava flow subangular block of mas-sive lava SBS664_175 20/04/17 10 :46 15°44.8475 -61°30.9454 747m Fault scarp area, North of Roseau volcano, towards the East Near bomb sag Volcani-clastic breccia 21x19x11.5 4.3 Polygenic breccia, clast supported, well consoli-dated SBS664_176 20/04/17 11 :14 15°44.8336 -61°31.0234 755m Fault scarp area, North of Roseau volcano, towards the Lava 21x19x11.5 4.7 Block of mas-sive lava of no clasts SBS665_194 22/04/2017 6 :48 15°46.9778 -61°28.4534 578 base of the clastic 47x32x1 12,800 canocalstic breccia purple color SBS664_179 20/04/17 19:29 -61°32.0489 15°46.2143 740 little dome at the south-west base of Coche volca-no lava 54X37X19 28 Very large massive brownish lava, very porphyric SBS664_180 20/04/17 21:29 -61°31.6962 15°46.1397 758 "Chicken leg" lava flow at the south base of Coche volca-no lava 40x34x28 23 Massive block of lava moder-ately vesicular SBS664_181 20/04/17 21:53 -61°31.7269 15°46.1554 726 "Chicken leg" formation at the south base of Coche volca-volcanic clastic beccia 37x17x19 10.2 rated volcanic with carbonate cement intra Coche volca-West of the Volcano-grained vol-no Small ridge, Fine to moderate-185 clastic beccia SBS664_186 21/04/17 03:26 -61°32.2212 15°46.6174 787 part of the NE scarp of lava ING 182, 179 and MISSING MISS-SBS_664_183, Piece of indu-SBS664_184 21/04/17 1:32 -61°31.9613 15°46.4044 649 Within the large crater located to the east of the Coche volcano summit Sedimen-tary sand-stone 8x2x4 7x3x2 0.08 Bioclastic fine grained dark grey sand with corals SBS664_185 21/04/17 2:22 -61°32.0344 15°46.4354 666 Eastern rim of the large crater locat-ed to the no summit hiboles Base of easternmost Same lava as phyric SBS665_193 22/04/2017 5 :36 15°47.3532 -61°28.7534 571 fault, base of the fault scarp Sedimen-tary sand-stone dant bioclasts 8 9,000 stone with abun-34,5 x 25 x Sedimentary sand-Souffleur slightly less Coche volca-crysts am-plateau SBS_664_188, east of the lava 32x22x11 8.18 Same lava as SBS_664_183, 182, 179. Larger pheno-no SBS664_189 21/04/17 6 :45 -61°32.7744 15°46.5180 830 Along the main fault scarp, N side of the can-yon, E of Carbona-ceous breccia 9x5x3 + 3 smaller pieces 0.27 Tuffaceous carbonate SBS665_191 22/04/2017 3 :11 15°47.8421 -61°28.8535 412 Souffleur fault, top of the plateau Mineral crust Small fragments 0,12 alternating beds of Ruggy concretion, fine sandy massive probably silica Top of Souf-sedimen-to very weakly lami-Hydrothermal de-SBS665_197 22/04/2017 9 :59 15°46,6911 -61°28,0155 441 fleur fault tary silt-24x25x12 8,000 nated brownish unit posit ? scarp stone and greenish unit concretion very finely laminated Coche volca-SBS664_190 21/04/17 08:33 -61°32.0112 15°46.6763 695 Main fault scarp, S of Les Saintes lava 12x9x7 lava similar to 0.049 Lava and gangue similar to SBS_664_189; SBS665_192 22/04/2017 3 :47 15°47.8232 -61°28.8235 414 Souffleur fault, top of the plateau tary sand-fine-grained layers stone and 4,5x2x2 ing coarse and 0,140 rock with alternat-Sedimen-11x4x2 Hard sedimentary no Paleosismites ?
	rich in crystals
	202 203 208 209

  The Data Annex folders available are given below, and a full listing of files within these folders is provided as a text file : 'DataFles_Listing.txt'

	Data folders associated with this cruise report :
	01_Logbook_Cruise
	02_Logbook_Rocks
	03_AUV_TechnicalReports
	04_AUVMicrobathymetryGrids
	05_AUVBackscatter
	06_AUV_Eh
	07_AUV_Nephelometer
	08_ROV_Reports
	09_ROV_Navigation
	10_ROV_VIdeoProblems
	11_ROV_RockSamples
	12_Chirp
	13_Pressure
	14_Litter
	15_Python
	16_Outreach
	17_ReportTables
	18_AUV_Renavigated
	19_LASER
	20_Ship_Bathymetry

SUBSAINTES'17 -Cruise report

acq_20170409T050616 09-Apr-2017 05:06:23 09-Apr-2017 05:17:22 0:10:59

acq_20170413T111714 13-Apr-2017 11:17:21 13-Apr-2017 11:39:10 0:21:49

acq_20170419T040537 19-Apr-2017 04:05:43 19-Apr-2017 04:44:08 0:38:25

J. Ferrer, A. Elibol, O. Delaunoy, N. Gracias, R. Garcia, Large-Area Photo-Mosaics Using Global Alignment and Navigation Data, MTS/IEEE OCEANS, Vancouver (Canada), Nov. 2007. DOI: 10.1109/OCEANS.2007.4449367

https://github.com/openMVG/openMVG

https://github.com/cdcseacave/openMVS

M. Jancosek and T. Pajdla, "Exploiting Visibility Information in Surface Reconstruction to Preserve Weakly SupportedSurfaces," International Scholarly Research Notices, vol. 2014, Article ID 798595, 20 pages, 2014. doi:10.1155/2014/798595

https://github.com/nmoehrle/mvs-texturing

ROV Dive #656 -Agoucha

from the plateau to the fault scarp, stratas are creating steps 04:39 fractures 04:44 scarp is broken/degraded, fallen blocks at base, no coseismic scarp 04:50 AUTT1 SBS_663_154 fault scarp, but taken on a fallen block 05:14 AUTT2 very fresh fracture N122°E, probably younger than 2004 05:29 unconformity under fine breccia 05:37 AUTT3 2 scarps; climbing up the 1st one, small coseismic scarp at the base? 05:45 corals (?) in the fault scarp; small coseismic scarp at the base? 06:03 along the 2nd scarp, looks like this scarp is only a strata 06:39 AUTT_3 SBS_663_155 piece of coral? fallen from outcrop; heading towards SE 06:49 small fracture 07:09 flying above a canyon. blocks, sediments but no fissures on strata 07:20 submarine slide scarp of the structure is irregular, laser on the top, ~20cm 07:30 scarp of the submarine slide dipping SW in slope direction 07:43 climbing up to cross perpendicularly the fault 08:03 along fault plane 4, no coseismic displacement, massive footwall 08:10 heading to next fault scarp. fracture NW-SE in indurated strata dipping SW 08:38 following scarp. we see blocks but no fractures neither scarp 08:43 small and really not clear offset in dejection cone, laser measurement ~30cm 08:47 heading to RC-02 09:01 submarine slide structure 09:08 RC-02, heading SW toward fault scarp 09:12 smooth fault scarp, fractures/cracks at the base, coseismic? Laser measurement 09:31 heading to S flank of the canyon, volcanic breccia, thin stratas

CAROTTE

Longueur de carotte : 13 cm Echantillons -carottier : 1 sac SBS 655 -Core 002 matériel extrudé, matériel qui a coulé lors de la sortie de la carotte du tube. Commentaires :Lors de la sortie de la carotte du tube sur le pont, le bouchon est resté au fond donc une partie de la carotte s'est vidée, le matériel a été récupéré dans le sac.

Description : 0-6 cm : boue hémipélagique, brun 7-13 cm : boue hémipélagique, gris https://fr.mathworks.com/matlabcentral/fileexchange/47595-mixing--mx-oceanographic-toolbox-for-em-apex-float-data?focused=7290001&tab=function

ROV core SBS655_Core003

ROV core SBS655_Core004

Kullenberg core SBS_17_PC_001

In Figure 7.5 bottom we show the comparison between the tide recorded locally, and the predicted tide. A detail of these records shows that the predicted tide shows a lag of ~ 1 hour (Figure 7.6), and starting on the 13th April 2017 and till the end of the recording (Figure 7.5 top and 7.7), the pressure record shows spikes of ~0.5 to ~0.8 m at the same phase of one of the semi-diurnal tides. The origin of these peaks is not known (currents ? instrumental problem -that is unlikely ?).

Cruise data

Data saving and backups

The 13 AUV dives (394 to 406) and the 14 ROV dives (653 to 666) are saved on the 6T drive SUBSAVE, in addition to the disks provided by the VICTOR Team.

For the AUV, each dive is stored in its own directory within the same hard drive, as it was delivered to us, in addition to the hard drive provided by the AsterX Team at the end of the cruise.

For the ROV, data of each dive is stored in its directory, which is composed of:

• ROV_data : the data as it was delivered to us • Adelie_ROV_data : Adelie export of the data • Navigation_data : NMEA process • Compressed_video : compressed ROV videos (main camera only) A backup of these data is stored on three 2T drives:

• BACKUP_ROV : all the AUV dives + ROV dives 653 to 658 • BACKUP_ROV2 : ROV dives 659 to 662 • BACKUP_ROV3 : ROV dives 663 to 666 For Nice, another backup is stored on three hard drives:

• GEOAZUR_SUBSAINTES (4T) : ROV dives 653 to 663