Keywords:

Science is based on data collection, analysis and interpretation. Where standard deterministic approaches are still the core of many science domains, the big data and Artificial Intelligence tool now provide powerful tool for a richer use of data. Today open science defines the conditions of sharing science data through FAIR principles, but in order to ensure an optimal processing of data in complex workflows, data must be "machine readable". This condition can only be achieved with a high level of exigence for proper description of data, technical and semantic interoperability, based on open standards, and implemented in research data infrastructures. Europe is implementing the EOSC (European Open Science Cloud) strategy to build upon disciplinary data infrastructures connected in an open cloud. With the support of the International Science Council (ISC/CODATA), other continents are developing similar approaches that will permit to address some of the big challenges of science (climate change, health and environment, urban ecosystems,…) which requires different disciplines to operate together. Geosciences have obviously an important role to play in those big challenges. Since more than 15 years, geoscientists have developed open standards for interoperability through IUGS/CGI and OGC in particular. To extend the use of their data in cross-disciplinary projects, it is therefore crucial that geoscientists remain at the forefront of standard development and extend their cooperation with others standardization bodies such as W3C (standards for linked open data) or BSi (BIM standards for built environment).


Damien Simon

Konstantinos Carriere

Nicolas Chalikakis

Karl Guibert

Marie Lellouche

Jean Mangin

Jean Kempf

Lapègue

Lellouche

An integrated hydrogeophysical approach for karst water assessment and management in humanitarian context -Mahafaly Plateau in Madagascar

établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

(1) UMR 1114 EMMAH INRA/UAPV, Avignon, France (2) Action Contre la Faim, Paris, France An integrated hydrogeophysical approach for karst water assessment and management in humanitarian context -Mahafaly Plateau in Madagascar -Carrière S.D. (1) , Chalikakis K. (1) , Guibert N. (2) , Lellouche K. (2) , Mangin M. (2) , Kempf J. (2) , Lapegue J. (2)  very different water dynamic between two boreholes (separated by 450m)  delayed water table ascent at Well 06  lateral transfer?  recharge of exploited aquifer seem dependent on intense rain events  low recharge in 2016  following drought period will be very difficult!

Hydrogeological and humanitarian issues

General water table map in

Example of Ankazomanga village Origin of salinity in aquifers

   understanding of the general geological structure  identification of drilling points  geology in Neogene in very heterogeneous and discontinuous • What water resource can we exploit? • Where dug boreholes? • Complex and discontinuous geology. • Poorly documented area in term of geology and hydrogeology. • How manage water resource in this humanitarian context? Hydrochemistry Example of Tokoendolo village Perspective • Meteorological and piezometric sensors and the team formed will allow to manage sustainably water resource • This part of Mahafaly plateau is now a unique observatory for drought warning in one of the largest karst system of the southern hemisphere. • 11 target villages  15 000 inhabitants • traditional water points  unsustainable  undrinkable  low productivity Main results: 6 positive boreholes  1 salinized borehole  6 failures  3 drilling "failures" replaced by wells  productive aquifer are sand and clayey sand  permeability from 1.10 -4 to 1.10 -7  deep karst resource is probably salinized  1 new ACF water point seems influenced by seawater  influence of cyclone? Method • 1 meteorological station in the middle of the study area (installed in 2016) • 10 automatic piezometric probes (installed in 2014 and 2016) • a team of local partners was formed for data acquisition and maintenance of equipment Main results:

Neogene aquifer N 10 km

	Method:
	• 217 points with differential GPS survey
	Main results:
	 general water table slope is West direction
	 at small scale, water table is very discontinuous
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	Water table
	elevation (m)
	Water point
	Village