Lisa Brunetti

Stefan Bott

Joan Costa

Enric Vallduví

Estela Puig

Josep Maria Fontana

Louise Mcnally

This paper presents a corpus of spoken narrative texts in Catalan, Italian, Spanish, English, and German. The aim of this corpus compilation is to create an empirical resource for a comparative study of Information Structure. A total of 68 speakers were asked to tell a story in an acoustically isolated room by looking at the pictures of three textless books. A total of 222 narrations resulted in about 16 hours of speech. The recordings have been transcribed and an original annotation of non-canonical constructions for the Romance subgroup has been proposed, namely of morphosyntactically/prosodically marked constructions that relate informational categories such as topic, focus, and contrast. Transcriptions and annotations of some selected high quality recordings have been aligned to the acoustic signal stream. The corpus is available in audio and text format.

Introduction

In this paper we present a corpus that has been developed within the NOCANDO project, 'Noncanonical constructions in oral discourse: a cross-linguistic perspective' at the University of Pompeu Fabra in Barcelona (Spain). The main interest of the overall project was to study the cross-linguistic variation in the overt marking of Information Structure (from now on, IS) in general and more specifically in the spoken, narrative register.

Researchers largely agree on the fact that languages use syntactically, morphologically and/or prosodically marked constructions to represent informational categories such as 'topic', 'focus ', 'contrast', 'background', etc. (cf. Vallduví 1992[START_REF] Vallduví | The linguistic realization of information packaging[END_REF][START_REF] Lambrecht | Information structure and sentence form: Topic focus, and the mental representations of discourse referents[END_REF], Erteschik-Shir 1997[START_REF] Steedman | Information structure and the syntax-phonology interface[END_REF], among many others). A large part of the research on IS, in particular within the generative framework, has mostly or exclusively relied on introspective judgements on sentences in isolation (see e.g. the works by Belletti, Rizzi, Zubizarreta, among many others). Nevertheless, explicit marking of IS through non-canonical constructions is much more frequent in spontaneous speech than in written or controlled discourse. In addition, a written text does not represent intonation, which is extremely important for the marking of IS.2 Furthermore, IS can only be truly understood if sentences are considered within their linguistic context. Sentences in isolation, such as those that are constructed for introspective judgements, are therefore suboptimal to understand the properties and function of informational categories.

A better source of data for the study of IS is therefore constituted by spontaneous speech corpora. Although speech corpora are available in literature, multilingual corpora that provide comparable data across languages are rather limited in number. Furthermore, access to speech corpora, in particular to the recordings, is often very restricted. These considerations led us to compile a corpus of spontaneous spoken narrative texts in five different languages: Catalan, Italian, Spanish, German, and English. The audio recordings are freely accessible for consultation. A taxonomy of non-canonical constructions (from now on, NOCANs) was also established and an annotation of the relevant subset of the taxonomy was added to the Romance subset of the corpus. The annotation is meant to facilitate the search for IS markings in the text. The corpus is available in audio and text format. Some selected recordings were also aligned to the transcription and annotation using the PRAAT software for acoustic analysis [START_REF] Boersma | Praat: doing phonetics by computer (Version 5.0[END_REF]). 3 Our corpus is publicly available under a Creative Commons license which only excludes commercial use. Use for research is free as long as the work is properly cited and all derivates of the corpus are shared under the same conditions. A more detailed description of the corpus and its annotation is given in the following two sections.

The corpus

A total of 68 speakers were asked to tell a story by looking at the pictures of three textless picture story books. The result is 222 narrations of about 2-9 minutes each (a total of about 16 hours of speech). The quantitative information for each language is given in the table below.

Speakers

Participants were mostly university students. The Catalan and Spanish speakers were mostly undergraduate or graduate students with an average age of 22 for Catalan (ranging from 18 to 30) and 20 for Spanish (ranging from 17 to 29). The Catalan speakers were from Catalonia (except one speaker from Valencia). The Spanish speakers were also from Catalonia (except one from Castilla y León), but they spoke Spanish as their first language. The Italian and English speakers had recently arrived in Barcelona. The average age of the Italian speakers was 29 (ranging from 20 to 56). They spoke geographically different varieties of Italian. The English speakers' average age was 27, ranging from 20 to 41. They came from the United States and Great Britain. A large number of the German speakers were also short-term residents in Barcelona, but a smaller number exclusively resided in Germany. The German speakers' average age was 34, ranging from 22 to 67. They came from different parts of Germany.

Methodology

Speakers were asked to narrate three stories to an experimenter while looking at the pictures of three textless books by Mercer Meyer. The books were given to each speaker in random order. Speakers were allowed to browse through the book before they started the narration. Most speakers were recorded in an acoustically isolated room while some were recorded with a portable recording device in a silent room. In both situations speakers were sitting in front of the experimenter. The books are entitled Frog goes to dinner, A frog on his own, and One frog too many and are about the adventures of a boy and his pet frog. Mercer Meyer's books have already been used in literature for the study of narration strategies in monolingual or bilingual children, adults, and second language learners (cf. Berman & Slobin 1994, Strömqvist & Verhoven 2004 and references quoted therein). The book used for those studies is Frog where are you?. We made a first set of pilot recordings with this book as well as with four other books. The three aforementioned books gave better results in terms of variety of NOCANs to be used by the speakers. 4 The story entitled Frog goes to dinner is about the disastrous effects of the presence of the frog in a very elegant restaurant. The advantage of this story is that it includes many different characters interacting with the frog in different ways so we could expect many topic changes. The story entitled A frog on his own tells of the adventures of a frog taking a walk by himself in the park. The frog interacts with other characters, but unlike in the dinner story, where the other characters may temporarily have a prominent role, in this story the frog always remains the central character in the narration. The story entitled One frog too many tells of the frog's jealousy of a younger frog who has become the boy's new pet. This story was chosen because it presents situations in which the speaker has to distinguish between the two frogs. These situations are interesting because they induce the speaker to adopt constructions that explicitly mark the informational category of contrast.

Transcription and segmentation

The recordings have been transcribed according to the guidelines for the transcription of the LIP corpus (Lessico di Frequenza dell'Italiano Parlato 'Frequency lexicon of spoken Italian [START_REF] De Mauro | Lessico di frequenza dell'italiano parlato[END_REF]. We represented the phenomena that are typical of spoken text: pauses, false starts, truncated words, laughs, hesitations, and vowel lengthening, among others. The transcription also followed orthographic standards.

Since the notion of 'sentence' is often not clear in spoken text, the segmentation was carried out by separating clauses: each segment generally contains one main verb, except for modal, temporal, and aspectual periphrases and verbless clauses. This criterion is very similar to that used in the transcription of CHILDES data [START_REF] Macwhinney | The CHILDES Project: Tools for Analyzing Talk[END_REF]. In order to recognize verb periphrases, we adopted the criteria proposed by [START_REF] Gavarró | Les perífrasis temporals, aspectuals i modals[END_REF]. Segments were separated as different XML-marked units; each unit was given a unique id and NOCANs were treated as attributes of segments. Some selected recordings were aligned to the transcription and annotation using PRAAT, as exemplified in figure 1. The alignment between text and speech signal makes it possible to quickly identify the relevant segments and locate them in the audio recording. Subsequently, all options for acoustic analysis offered by PRAAT may be exploited.

The annotation

An annotation of non-canonical constructions (NOCANs) was carried out for the three Romance languages of the recording: Catalan, Spanish, and Italian. The reason for choosing these languages is that they are typologically similar. For instance, they all have a relatively free word order with SVO being the canonical one; they allow for null subjects, and they display left and right dislocations, including clitic dislocations. Their similar linguistic properties are parallel to their similar strategies for expressing informational notions. All these languages largely use syntax for this purpose, as opposed to languages like English, which nearly exclusively use prosody (see [START_REF] Vallduví | The linguistic realization of information packaging[END_REF]. The NOCANs found in these languages are indeed very similar or identical cross-linguistically. Despite these similarities, however, it has been shown in literature (cf. [START_REF] Villalba | La dislocació a la dreta en català i castellà, microvariació en la interfície sintaxi/pragmàtica[END_REF][START_REF] Leonetti | Alcune differenze tra spagnolo e italiano relative alla struttura informativa[END_REF]) that the use of individual NOCANs within Romance languages can vary considerably in frequency and function. A comparison between these languages is therefore important in order to show what such (quantitative or qualitative) differences are.

We must stress that an annotation of NOCANs is extremely rare in existing corpora, even those created with the explicit purpose of studying IS. The only example we are aware of is the MULI corpus ('MUltiLingual Information structure') of read German and English newspaper texts [START_REF] Baumann | Information Structure and Prosody: Linguistic Categories for Spoken Language Annotation[END_REF]. Its annotation, which only concerns a small part of the corpus (only 250 sentences for the German part), includes NOCANs such as clefts, pseudo-clefts, extraposition, fronting, and passive sentences. Informational categories themselves are also annotated. Apart from its reduced extension, the main limit of this corpus is that it is not made of spontaneous speech, which is a crucial aspect for the study of IS, as argued above. Note further that read intonation is known to be different from intonation in spontaneous speech, in particular concerning the marking of informational categories [START_REF] Hirschberg | Prosodic and other acoustic cues to speaking style in spontaneous and read speech[END_REF]. We therefore think that our corpus provides an empirical resource which had been missing up to now and which can enhance the research on IS and on its interaction with the other parts of grammar.

Finally, it is important to clarify the difference between NOCANs as objectively observable events in language production, and IS proper. Studying IS can be compared to hunting for ghosts in that both phenomena are not directly and objectively observable. While ghosts manifest themselves through knocks and falling objects, IS units such as topics and foci manifest themselves through linguistic marking (i.e. NOCANs). In both cases we have to deduce the existence and presence of the object we are primarily interested in from objectively observed events. That explains why in the creation and annotation of the corpus we decided not to annotate directly IS units but the NOCANs which mark them. Although annotating IS categories is possible, in principle, the resulting annotation is less reliable because extrasentential factors such as the linguistic context or even extra-linguistic factors such as the speaker's intentions have to be taken into account, and that often induces the annotator to make subjective choices. Furthermore, the annotation of IS categories is often hardly free from the bias of a specific theory on IS. In fact, a considerable amount of disagreement is still found among different schools concerning the identification and the definition of IS categories. The annotation of NOCANs is, thus, more neutral and objective.

Non-canonical constructions (NOCANs)

As we said above, NOCANs are marked constructions from a syntactic, morphological and/or prosodic point of view. Given the freedom of syntactic possibilities existing in the three Romance languages, the NOCANs we annotated where mostly morpho-syntactically marked constructions. The only exceptions are clear cases of deaccenting and focus fronting. In the latter construction, syntactic fronting is accompanied by prosodic fronting of the focal accent, and when the fronted focus is a preverbal element, fronting is only revealed by prosodic marking. It must be made clear that our preference for syntactic NOCANs does not mean that prosody plays no role in the representation of IS in the three Romance languages under study. Nevertheless, a fine-grained phonological annotation (e.g. of different types of pitch accents) is a very complex task that goes beyond the scope and the expertise of our team. It must be pointed out, however, that although phonological properties are not annotated, the relevant information is stored in the audio recordings and a subset of the recordings is aligned with the transcription and thus prepared for in-depth phonetic and phonological analysis. Our corpus is therefore potentially ready to be enriched with this kind of annotation in the future.

As we said above, our interest in NOCANs is in the fact that these constructions reveal the IS properties of a sentence. More precisely, NOCANs usually single out a specific information structural unit, such as a topic or a focus. Some constructions are used for instance to distinguish a topic from its comment. A topic expression indicates the referent, about which the sentence conveys some information, which is represented by the comment [START_REF] Strawson | Identifying reference and truth-value[END_REF], Reinhart 1982[START_REF] Vallduví | The informational component[END_REF]). The construction called 'clitic left dislocation' [START_REF] Cinque | Types of A'-Dependencies[END_REF]) is used in many Romance languages precisely to make such a distinction. An example is given by (1), from the Spanish sub-corpus:

(1) Al hombre se le cae el café to-the man RFL to-him falls the coffee Ind. object obj.cl. Verb Subject "The man drops the coffee"

The indirect object al hombre is left dislocated; the canonical position would be the post-verbal one. The left dislocation leaves a remnant clitic pronoun (le) in verb adjacent position and the subject occurs post-verbally. By occupying a sentence initial, pre-verbal position, the indirect object is easily identified as the sentence topic, while the rest of the sentence (verb + subject) constitutes the corresponding comment.

Another informational partition that can be marked by specific NOCANs is the focusbackground partition. The focus is the informationally most relevant part of a sentence in a particular context. In the construction exemplified in (2), the focused direct object (capital letters indicate focal accent) occupies a non-canonical preverbal position (without clitic remnant, in this case).

(2) Pure la LINGUACCIA, gli fa, la rana. even the tongue to-him cl he-puts-out the frog Dir. Object Verb Subject "Even the tongue did the frog put out to him" Italian

The construction hence explicitly and unambiguously separates the focus element from the rest of the sentence (the background). A focus-background construction can also be represented by a cleft sentence, as in (3):

(3) i és ELLA que està a punt de prendre's el biberó and is her who is about to take for-herself the baby-bottle "and it's him who is going to drink from the bottle" Catalan A cleft is made of two clauses: one introduced by the verb 'to be', and the other introduced by a complementizer. The two clauses allow for a clear separation of the focus from the background: the copular clause is occupied by the sentence focus (the subject ella in 3), and the other clause represents the remaining background.

Taxonomy of NOCANs

A full list of NOCANS that are represented in our taxonomy is given in Table 2. Whenever a certain construction represents a particular case of a more general construction, we assigned the former a label that contains the label of the latter. For instance, the label arbnsbj for arbitrary subjects, which are a particular case of null subjects, contains the label of null subjects: nsbj. We subdivided our labels into three groups: NOCANs that are specific to the subject, NOCANs that concern all arguments, and sentential NOCANs. We will describe them in details in the following subsections.

Label

Labels specific to subjects

A subset of labels that we have proposed is specific to subjects. The three Romance languages have a default SVO order, so all constructions in which the subject did not occupy a pre-verbal position are marked as NOCANs. The label for post-verbal subjects is sbjinv ('subject inversion'). A Catalan example is given below:

(4) Els va acompanyar el taxista them cl PAST take the taxi-driver "The taxi-driver drove them" Catalan

The subject occurs post-verbally, while the direct object is moved to a pre-verbal position, thus rendering an OVS order. Inversion usually leaves the subject in focus or part of the focus. Note however that the informational role of the subject does not only depend on its postverbal position. If the postverbal subject is deaccented, it will be part of the background. For this reason, a deaccented post-verbal subject is marked with an additional label: sbjinv_deacc. In (5), aquest nen (orthographically separated from the verb by a comma) is the deaccented subject.

(5) ...que està disfressat, aquest nen for is dressed-up this child "...for this child is dressed up" Catalan Since all of the Romance languages we examined may avoid expressing the subject overtly, we frequently find null subjects (nsbj). We only annotated nsbjs in finite clauses, as infinitive ones are canonically subject-less. Null subjects generally refer to an entity that is salient in the context. They function largely in the same way as unaccented pronouns in languages like English. They can neither be focal nor topical. In (6), the nsbj in the perché-clause refers to the boy, namely an entity that is already salient in the context (it is the topic of the preceding clause).

(6) Invece il bambino è molto contento, perché ha salvato la sua rana instead the boy is very happy because has saved the his frog "The boy on the contrary is very happy, because he saved his frog" Italian A special case of nsbjs are those which occur in coordinated clauses. We annotated them apart with the label nsbj_c. The reason is that these constructions can be interpreted as VP coordination, in which case subject omission in the second conjunct is expected.

(7) Entonces la tortuga lo ve y hm se lo dice al niño Then the turtle it sees and uh him it tells to-the boy "Then the turtle sees it and she tells the boy" Spanish A null subject may not refer to a definable entity but receive an arbitrary interpretation. While in English a plural pronoun is used in these cases (e.g. they killed Kenny), in Romance these subjects are necessarily non-overt. We assigned them the label arbnsbj for 'arbitrary (null) subjects'.

(8) Y un día a este niño le regalaron pues una caja muy grande and one day to this boy to-him cl they-gave well a box very big "And one day this boy received a large box" Spanish

The importance of marking arbnsbjs is that they seem to play a role in sentence topic selection: the fact that the subject is arbitrary in reference makes the object a potentially better topic (cf.

Brunetti 2009a

). An example of omitted argument that cannot without controversy be called subject is the argument of a copula sentence. In the subordinate clause of (9), the copula verb occurs in initial position and there is only one argument in the sentence (la seva granota). Since copula constructions always need two arguments, evidently one is missing here. However, it is not entirely clear that the missing argument is really the subject [START_REF] Alsina | La inversió copulativa en català[END_REF]). In order to keep such cases apart from uncontroversial cases of nsbjs, we label them narg ('null arguments'). ( 9) i llavors en Jaume es va adonar que que, home, era la seva granota and then the Jaume RFL PAST realizes that that well was the his frog "and therefore Jaume realizes that that, well, it was his frog" Catalan Finally, constructions are annotated where the subject is separated from the verb by intervening material. If the separating material is another argument, then the subject is dislocated even though no subject clitics exist in these languages to mark the dislocation explicitly. We will discuss this case below when we introduce dislocation constructions. When the subject is separated from the verb by adjunct material, its syntactic position and its informational status are less clear. That is why we give these constructions a label apart: sbj-sep ('subject separation').

Labels for all arguments

We have marked different kinds of argument detachments. Since object clitics exist in these languages, object dislocations are marked with a clitic remnant adjacent to the verb. Clitic left dislocations have been annotated with the label clld. As we said in section 2, ex. (1), the dislocated element is generally recognized as the sentence topic (cf. [START_REF] Vallduví | The informational component[END_REF][START_REF] Benincà | L'ordine delle parole e le costruzioni marcate[END_REF][START_REF] Benincà | L'ordine delle parole e le costruzioni marcate[END_REF], [START_REF] Zubizarreta | Topic, Focus and Word Order[END_REF][START_REF] Zubizarreta | Las funciones informativas: tema y foco[END_REF], among many others).

There is a certain variation among Romance languages with respect to the use of clitics in object dislocations. When the dislocated element is not accompanied by a clitic remnant, the construction is labelled ld ('left dislocation'). In Italian, the remnant clitic of an indirect object is not obligatory (cf. 10). Its presence is associated with register, namely it is more common in colloquial speech.

(10) A un bambino un giorno arriva un regalo to a boy one day arrives a present "One day a boy receives a present" Italian

Given that there are no subject clitics in the three Romance languages, a preverbal subject can be demonstrated to be left dislocated only if it is separated from the verb by another argument.

In that case, the subject will be assigned the same label ld.

(11) Esta a mí no me quiere nada bien this-one to me not me cl loves no good "this one doesn't love me at all" Spanish Following [START_REF] Vallduví | The informational component[END_REF], among others, we assume that the informational function of an ld is not different from that of a clld (it marks the sentence topic).

Another left dislocation construction existing in these languages is 'hanging topic' (cf. [START_REF] Cinque | The Movement Nature of Left Dislocation[END_REF][START_REF] Cinque | Types of A'-Dependencies[END_REF]. We assigned it the label ht.

(12) La rana grande, la situación no le gustaba mucho the frog big the situation not to-her cl pleased much "As for the big frog, she didn't like the situation at all" Spanish

An ht is a detached element that has no marking of grammatical function (it is never a Prepositional Phrase, always a Noun Phrase) and is obligatorily resumed by a pronoun expressing its grammatical function. Unlike a regular clld, an ht can also be resumed by a strong pronoun or a demonstrative. If the ht is a subject or an object, the construction can only be distinguished from a clld by the presence of a strong pronoun or a demonstrative. 5 As the name itself makes clear, this construction marks topic material as well.

Clitic right dislocations (clrd) are dislocations of an argument to the right, with resumption of a clitic inside the clause. Unlike cllds, the clitic is always optional. Prosodically, a clrd is deaccented or has a reduced accent. Indeed, clrds must always be old and salient in the discourse context [START_REF] Vallduví | The informational component[END_REF][START_REF] Bott | On the semantic and contextual factors that determine topic selection in Italian and Spanish[END_REF], Brunetti 2009c), and prosodic weakness is precisely a marking of this constraint.6 In ( 13), for instance, the frog has been mentioned in the immediately preceding discourse context.

(13) el gat ja l'ha vist, a la granota. the cat already it cl has seen to the frog "The cat already SAW the frog" Catalan

When the right dislocated argument has no resumptive clitic, the construction is simply called 'right dislocation' (rd). It mostly concerns cases in which the dislocated element is a subject. A further related construction is 'clitic doubling' (cldbl). In terms of word order, cldbl is similar to clrd. The difference between the two lies in their intonation: while a right dislocated argument is deaccented, with cldbl the verb and the argument are in the same intonational unit, the nuclear accent falls on the doubled argument, and either the whole VP or the argument are in focus. so the turtle it cl sees and to-him cl it cl says to-the boy "So the turtle sees what happened and tells the boy everything" Spanish Sometimes the object is separated from the verb by non-argument material, although it still occurs postverbally. We label this construction obj-sep ('object separation'). Prosodically, the object is not deaccented, which means that it represents the focus or part of the focus, together with the verb. Dislocations to the left single out topic material. An exception is focus fronting (focfr), which we already mentioned in section 4, ex. (2). The distinctive feature of this NOCAN is the prosodic marking of the affected phrase, which is assigned focal accent. In these languages, the focal accent canonically falls at the end of the clause, while in this construction it is in sentence initial position. Prosodic marking may not be accompanied by syntactic fronting. That happens for instance when the expression is the subject, as in ( 15).

(15) A questo punto anche LARA è dispiaciuta at this point even Lara is sorry "At this point even Lara is sorry about that" Italian Finally, we marked deaccented material (deacc), namely absence of a pitch accent on a word that would otherwise be expected to be accented [START_REF] Swerts | Prosodic Marking of Information Status in Dutch and Italian: A comparative analysis[END_REF]. Romance languages do not usually recur to deacc, although this is very common in other European languages (e.g. English). Nevertheless, we can sometimes find deaccented material in Romance, as in ( 16). The main accent would be expected to be on rana. On the contrary, the accent falls on simpatica, and the adjunct is deaccented. Deacc cannot be focal material, and it is not usually topic either.

(16) ma Lara non è molto SIMPATICA, con questa rana but Lara not is very nice with this frog "But Lara is NOT very nice, towards this frog" Italian

Focfr and deacc (including sbjinv_deacc, see ex. 5) are the only NOCANs that explicitly (and in the case of deacc, exclusively) make reference to prosodic, rather than syntactic, noncanonicity.

Labels marking non-canonical types of sentences

The NOCANs described so far all affect isolated parts of a sentence. However, there is also a series of NOCANs that affect the entire sentence. We will present them in this section. Presentational sentences (pres) are used to introduce new referents and states of affairs. They usually only contain new information. In Italian their most common form is Locative clitic + verb 'to be' + NP (see 17); in Catalan the corresponding form is Locative clitic + verb 'to have' + NP, and in Spanish they are typically introduced by the impersonal form of haber 'to have' (hay, había, etc.).

(17) C'era una volta un bambino there was one time a boy "Once upon a time there was a boy" Italian

Passive constructions (pass) also have a relation to IS. On one hand, the direct object of the active form becomes the subject of the corresponding passive form and therefore occupies a (canonical) preverbal position. Since such position is typically occupied by the sentence topic, passives may favour a topic interpretation of the direct object. Furthermore, in passives the subject of the active form corresponds to an adjunct by-phrase, which can be omitted. The main function of passives is in fact to omit or hide the agent of the event, which in the active form is always the subject. The agent may be hidden for various reasons, one being for instance that the speaker ignores its referent. In this sense, passives carry out a similar function as arbitrary subjects (see 9), in that they favour the presence of an indirect object (when given) as sentence topic (Brunetti 2009a). Impersonal constructions (impers) were also annotated. Not even these verbs select an agent, so they are supposed to have similar effects to arbnsbjs and passives with respect to topic selection, as argued by Brunetti (2009a). (19) y lo que pasa es que el barquito se hunde and it that happens is that the little-ship IMPERS sinks "and what happens is that the boat sinks" Spanish Finally, inv-psclefts are psclefts that occur in a reversed order, namely the NP follows the copula verb.

Corpus exploitation

The corpus and the annotation of NOCANs provide a valuable source of qualitative data to be used as examples in theoretical studies on IS (see for instance Brunetti 2009a[START_REF] Bott | On the semantic and contextual factors that determine topic selection in Italian and Spanish[END_REF]. The corpus can obviously also be exploited for quantitative analyses of specific informational phenomena (see [START_REF] Mayol | Pronouns in Catalan: information, discourse and strategy[END_REF]Clark in press, Brunetti 2009b). In the following section we present a general overview of the annotation results on the three Romance subcorpora, and we will propose some possible lines of research that may stem from them.

An overview of the annotation results

In Table 3 we report the most interesting results concerning the differences in frequency of NOCANs in the three Romance languages. The relative frequencies are given with respect to the total number of finite clauses. A first general observation to be made is that the overall number of NOCANs is relatively low. This is indeed expected as NOCANs are marked constructions with respect to the linguistic properties of a language. Although spontaneous speech is assumed to have more NOCANs than controlled speech or written text, this does not mean that the number of NOCANs in the former is very high. 8 An exception to low frequency is nsbj. Catalan, Italian and Spanish all allow for subject omission in finite clauses. In the corpus, however, nsbjs are in practice nearly as frequently as overt ones. Therefore, an empirical support for assuming that these languages canonically have overt subjects is rather weak. Although the corpus annotates nsbjs as NOCANs, we can actually conclude that they are at least as canonical as overt subjects. Another NOCAN that has a higher frequency than the others, but low enough for the phenomenon to be still undoubtedly considered as non-canonical, is sbjinv. Among the factors that determine sbjinv, our data show that an important role is played by the type of subject. We found that a high percentage of inverted subjects correspond to the pronoun tots (Cat.) / todos (Sp.) / tutti (It.) 'all'. We also found a strong correlation between certain situations in the storyline and inversion. There are two points in the narrations where nearly all speakers use sbjinv. In both cases the character referred to by the subject had been absent from the story for some time and makes a sudden re-appearance. Indeed, in these contexts the subject is in focus and we know that a focused subject tends to occupy a postverbal position whenever possible. The data also confirm the well known relation between sbjinv and type of verb. In general, unaccusative verbs (e.g. 'come in', 'fall down', 'appear', etc.) accompany inversion in our data.

Another interesting observation to be made on the annotation results is the rather even distribution of NOCANs among the three languages. This is in itself an interesting fact. The variation among individual speakers is higher than the variation across languages. For example, we observed that 3 out of the total of 5 passives in the Spanish subcorpus were produced by only one speaker. Another good example is impersonals. Their overall frequency in Romance is 2.1%, but we find speakers who do not use impersonals at all, while a small set use them with a high frequency of approximately 5% and one speaker even used it with a frequency as high as 10.3%. We conclude from this that NOCANs are also subject to personal style and variation.

Dislocations also behave in a very similar way in the three languages. This result is rather unexpected, as it has been claimed in literature that these three languages vary with respect to the frequency and use of dislocations. For instance, it has been argued that clrds and rds are much more common in Catalan than they are in Spanish (see e.g. [START_REF] Villalba | La dislocació a la dreta en català i castellà, microvariació en la interfície sintaxi/pragmàtica[END_REF], who studied right dislocations in a Catalan theatre play and its Spanish translation). The frequencies we obtained from the corpus seem to contradict these conclusions. Upon closer inspection, 8 Cf. e.g. the work by Carter-Thomas and Rowley-Jolivet (2001) on English written and spoken scientific discourse. These scholars have shown that the frequency of certain NOCANs in a written article is much lower than in the corresponding spoken presentation. What can be deduced from their data, however, is that there is a rather low number of these constructions in both kinds of discourse. however, we found that 5 out of the 7 clrds and all 4 rds in the whole corpus were produced by only one speaker. In addition to that, the Spanish native speakers we consulted confirmed that all these instances are grammatical but highly marked. These cases in fact look like literal translations from Catalan. So we considered as plausible that the speaker in question, who was born and raised in Catalonia, showed a strong interference from Catalan. If we exclude that speaker, we find that the total of clrds and rds in Spanish only have a frequency of 0.2% (which would confirm Villalba's findings).

Finally, clitic doubling, although syntactically similar to dislocations, constitutes a case apart. We observe a clear difference between Catalan and Spanish on one hand and Italian on the other: the frequency of cldbl in the former languages is much higher than in the latter. This result is not surprising, as cldbl in Italian has morpho-syntactic restrictions that are totally absent in the other two languages. For instance, in Italian the clitic is only fully accepted if followed by another clitic (see [START_REF] Benincà | L'ordine delle parole e le costruzioni marcate[END_REF][START_REF] Benincà | L'ordine delle parole e le costruzioni marcate[END_REF]:151).

Conclusion and future work

The corpus we have presented in this article is an important resource for the study of information structure and potentially for the study of all phenomena found in spoken narration. The availability of high quality recordings allows the study of phonetic and phonological phenomena. The annotation of NOCANs identifies IS-related constructions within their context of appearance, and allows a quantitative analysis of them.

The developments and extensions of the corpus that we foresee in the near future take several directions. With respect to corpus compilation, we are interested in extending the corpus to other types of discourse, in particular spoken dialogue. Such an extension would allow a quantitative and cross-linguistic study of the differences between monologue and dialogue with respect to the use of NOCANs and the organization of information. The cross-linguistic side of the corpus can also be improved by collecting recordings of other languages, both within the Romance family (Portuguese, Romanian) and different language families. With respect to the annotation, an obvious extension concerns the annotation of NOCANs in the Germanic subcorpora already available (English and German). Further annotations that may contribute to a better understanding of IS-related phenomena are conceivable. A phonological annotation of prosodic grouping and types of accents would offer a more detailed description of prosodyrelated IS phenomena. Semantic annotations of various kinds -thematic roles, animacy, degree of saliency of a referent in the discourse, etc. -would also contribute to a better understanding of certain phenomena.

As a last remark, it is important to stress that the NOCANDO corpus is publicly available and third parties are allowed (and encouraged) to enlarge and enrich the corpus both in terms of further annotations and of further languages.

Figure 1 :

 1 Figure 1: Audio-transcription alignment and phonetic analysis with PRAAT.

( 14 )

 14 Entonces la tortuga lo ve y se lo dice al NIÑO.

(

  18) e lui continua hm a indicare non si sa dove and he keeps hum to point not IMP knows where "And he keeps pointing who knows where" Italian Finally, we annotated three constructions where the sentence is divided into two separated clauses, and each clause typically represents a particular informational unit: cleft sentences (cleft), pseudo-cleft sentences (pscleft), and inverted pseudo-clefts (inv-pscleft). A cleft sentence has the following syntactic form: Copula verb + XP + Comp + S missing XP. As already seen in section 4, ex. (3), the XP is the focus (typically a contrastive one), and the remaining clause represents the background. Psclefts are related to cleft sentences. They have the form: NP + relative clause + Copula verb + NP or S, but unlike ordinary clefts, they do not mark a focus-background structure: it is the second part of the construction that is in focus instead (cf. que el barquito se hunde in 19).

Table 1 : Quantitative information on each language represented in the NOCANDO corpus.

 1

		Catalan	Italian	Spanish	German	English
	Speakers	19	16	13	9	11
	Recording time 4:02:43 h	4:04:32 h	2:35:20 h	2:09:13	2:32:20 h
	Word count	37555 w	27392 w	25077 w	15944 w	21970 w
						(estimated)
	Segment count 5856 seg	4306 seg	3801 seg	2154 seg	3140 seg
						(estimated)

Table 2 : The taxonomy of NOCANs for the Romance languages in the NOCANDO corpus

 2

Absolute and relative frequencies of some NOCANs with respect to segments.

  7

	cldbl		92	2.1 % 7	0.2 %	61	2.1 %
	cleft		3		4		2
	pscleft + inv-pscleft 40	0.9 % 10	0.3 %	37	1.28 %
	pass		5	0.1 % 67	2 %	7	0.24 %
	Table3:
			Catalan	Italian		Spanish
	overt sbj	1561 35.7 % 1262 38. 9 % 1027	35.5 %
	nsbj		1665 38.1 % 1173 36.1 %	1084	37.5 %
	arbnsbj		22	0.5 % 7	0.2 %	32	1.1 %
	sbjinv		332	7.6 % 215	6.6 %	265	9.1 %
	clld+ld		62	1.4% 44	1.35%	39	1.,35 %
	clrd+rd		22	0.5 % 21	0.64 %	11	0.38 %
	ht		10	0.2% 2	0.06%	9	0.3 %
	7	More precisely, we counted all main clauses and adjunct clauses, and we excluded all non-finite clauses
	(infinitives, gerunds) and relative clauses.

  The percentages of all NOCANs including nsbj is 72.5% (uniformily distributed in the three languages: 72.2% in Catalan, 74.4% in Spanish, 71.1% in Italian). Without nsbj, the percentage drops consistently, but not dramatically, to 24.1% (23.57% in Catalan, 26.3% in Spanish, 22.8% in Italian).

In fact, it is the most important resource for marking IS in certain languages, such as English.

Praat is available at http://www.praat.org/.

It must also be noted that Frog where are you? has been preferred in past literature because it did not presuppose a specific socio-cultural background so it could be used with speakers of different origins. Since our purpose was not to study the sociolinguistic aspects of narration, we did not consider the socio-cultural implications of a story as a relevant factor for choosing it or not.

In fact, prosody also contributes to distinguishing between the two constructions.

 Within Vallduví's (1992) model of IS, clrd and clld identify different informational units, called tail and link respectively.

for their comments and questions. This research has been partially funded by the Spanish Ministry of Education and Science project OpenMT (TIN2006 15307-C03-02). The NOCANDO project was funded by the Spanish Secretaria de Estado de Universidades e Investigación of the Ministerio de Educación y Ciencia (n. I+D HUM2004-04463).


Hideo Aochi
email: h.aochi@brgm.fr

Farid Smai

Jonny Rutqvist

REPEATING EARTHQUAKE BEHAVIOR DUE TO FLUID CIRCULATION THROUGH TOUGH-BIEM SIMULATION

We carry out TOUGH-BIEM simulations for modeling fault slip behavior triggered by fluid circulation in a geothermal context. The TOUGH2 code is used for modeling the pore pressure evolution within a fault and then a boundary integral equation method is applied for simulating fault slip, including aseismic slip on the entire fault plane and fast slip on seismogenic asperities. It is assumed that Coulomb friction and a slip-strengthening-then-weakening friction govern the fault slip. The pore pressure change due to injection is increasing logarithmically (fast at the beginning and later slow) so that the induced aseismic slip is fast at the beginning and slows down later. The fault slip on the asperities are periodic, and its recurrence depends on the previous aseismic slip in surrounding fault areas. When the two asperities are separated, their behavior is independent. When they are close each other, the recurrence timing of each asperity is disturbed. This feature is consistent with repeating earthquakes observed associated with geothermal stimulation experiments. The configuration of this study is simple for our demonstration, but the combination of TOUGH2-BIEM simulation would allow for studies of complex seismic fault behavior in different geological applications of fluid injections.

INTRODUCTION

Repeating earthquakes have been found from seismological analyses in the context of induced seismicity such as geothermal injection [START_REF] Bourouis | Evidence for coupled seismic and aseismic fault slip during water injection in the geothermal site of Soultz (France), and implications for seismogenic transients[END_REF] and these are indicators to assess fault reactivation due to the pore pressure change. The seismogenic models of natural earthquakes proposed for plate interfaces is applicable for studying the occurrence of induced seismicity along fault planes. The variety of seismic behaviors in subductions strongly depend on the fault rheology and high-pressure fluid existence (e.g. Lay et al., 2012;[START_REF] Ide | Modeling fast and slow earthquakes at various scales[END_REF][START_REF] Saffer | The frictional, hydrologic, metamorphic and thermal habitat of shallow slow earthquakes[END_REF].

In geomechanics, fault reactivation and induced seismicity have been modeled through hydromechanical coupling in geothermal injection and geological storage of CO2 (e.g. [START_REF] Rutqvist | A modeling approach for analysis of coupled multiphase fluid flow, Heat transfer, and deformation in fractured porous rock[END_REF][START_REF] Baisch | A numerical model fo fluid injection induced seismicity at Soultz-sous-Forêts[END_REF][START_REF] Rutqvist | The geomechanics of CO2 storage in deep sedimentary formations[END_REF]. In this context, the TOUGH2 code has been used with many geomechanical modeling tools (review in [START_REF] Rutqvist | An overview of TOUGH-based geomechanics models[END_REF]. In particular, TOUGH-FLAC (Rutqvist et al., 2014) allows modeling an entire process of an induced earthquake on a fault including dynamic rupture propagation and ground shaking. In this study, we present a combination of TOUGH2 with BIEM, a code based on the boundary integral equation method.. BIEM is generic name of boundary element approach, especially based on theoretical integral equation of linear elasticity and is applied on dynamic rupture propagation and quasi-static faulting process on faults in 2D anti-/in-plane and 3D model domains (e.g. [START_REF] Aochi | Three-dimensional nonplanar simulation of the 1992 Landers earthquake[END_REF]. BIEM is usually more convenient than any volumetric methods (finite difference and finite element methods) and flexible to treat the boundary condition on the fault elements. In this study, we demonstrate a fluid injection in a vertical fault core zone in 3D in which the fault plane (thin fault core) is a 2D plane for faulting. We study how the pore pressure change activates the aseismic shear fault slip and how this aseismic slip loads small seismogenic asperities in analogous with observations at a geothermal site.

MODEL AND METHOD

In order to study this behavior, we combine TOUGH2 (EOS1) simulations [START_REF] Pruess | TOUGH2 User's Guide, Version 2.0[END_REF] of fluid flow along a fault segment with a boundary integral equation method (BIEM; [START_REF] Smai | Study of Algorithms for Fast Computation of Crack Expansion Problem[END_REF][START_REF] Aochi | Role of multi-scale heterogeneity in fault slip from quasi-static numerical simulations[END_REF] simulating earthquake faulting under quasi-static equilibrium. According to the Soultz-sous-Forêt, East France, geothermal case presented by [START_REF] Evans | Microseismicity and permeability enhancement of hydrogeologic structures during massive fluid injections in to granite at 3 km depth at the Soultz HDR site[END_REF] and [START_REF] Bourouis | Evidence for coupled seismic and aseismic fault slip during water injection in the geothermal site of Soultz (France), and implications for seismogenic transients[END_REF], we prepare a planar, vertical fault segment of 100 m x 100 m at depth containing seismogenic asperities.

For TOUGH2 simulations, we consider that the fault segment is homogeneous related to hydrothermal parameters, over a large fault core of 500 m x 500 m with a width of 0.04 m (Figure 1). An injection profile of step-like increase from 0.04 l/s to 6 l/s over a few days is given. In the field experience of Soultzsous-Forêt, the pore pressure change does not increase proportionally with the injection rate and is saturated gradually. This is probably because the injected fluid circulates somewhere else other than the fault core of or the fault core is more permeable when pore pressure is high. This may be modelled by permeability variation such that permeability becomes higher as the pore pressure increases (e.g. [START_REF] Douglas | Using estimated risk to develop exploitation strategies for Enhanced Geothermal Systems[END_REF]. In this study, permeability is variable according to the reservoir pressure (e.g. [START_REF] Miller | Aftershocks driven by a high pressure CO2 source at depth[END_REF]. The two of the outer boundaries have drained (constant pressure) conditions in order to avoid too much pressure on the modeled fault region.

The pore pressure change simulated by TOUGH2 drives the BIEM simulation. As shown in Figure 1, the fault domain is divided into three areas: (A) a background domain that is not reactivated by pore pressure and therefore experience no seismic slip, (B) an aseismic area out of seismogenic asperities activated by pore pressure with slip governed by Coulomb friction and (C) seismogenic asperities with slip governed by a non-linear, cycling friction law. Letting the pore pressure change, shear stress change and fault slip Δ , Δ , and Δ , respectively, we write the boundary conditions of the three areas as follows:

Δ = 0 (A) Δ = -Δ (B) Δ = exp 1 - (C) (1)
where µ is Coulomb friction coefficient, is asperity strength, and is characteristic displacement. Area C governed by slip-strengthening-then-weakening friction corresponds to seismogenic asperities which may repeat under continuous loading [START_REF] Aochi | Role of multi-scale heterogeneity in fault slip from quasi-static numerical simulations[END_REF]. For our first attempt, we prepare only two asperities of size of 5 m and 10 m radius to demonstrate their seismic periodicity and interaction. The characteristic displacement, in Equation C is scale-dependent

RESULTS

Figure 2 shows an example of simulation results. The pore pressure change calculated from the TOUGH2 simulation is uniformly given on the fault segment. Considering the well-head pressure of about 8 MPa observed in the experiment [START_REF] Evans | Microseismicity and permeability enhancement of hydrogeologic structures during massive fluid injections in to granite at 3 km depth at the Soultz HDR site[END_REF], a change of about 3 MPa on the fault segment at about 200 m distance should be reasonable. The sliding area includes all of area B,including two asperities (area C), defined in Figure 1. Asperities respond with a stick-slip behavior , including stress accumulation and release a few times during this injection. Note that the background shear stress (area B) continues decreasing as the pore pressure increases, while shear stress on seismic asperities (area C) is constrained between 0 and 0.4 MPa according to Equation (1). Regardless of the assumed friction, the stress accumulation is faster on smaller patches than larger ones [START_REF] Aochi | Role of multi-scale heterogeneity in fault slip from quasi-static numerical simulations[END_REF]. The small asperity (5 m radius), which repeats three times, roughly correspond to an area of magnitude 0.

In the case where the two asperities are close enough or superposed, the periodic behavior becomes irregular due to the interaction. Sliding on the small asperity may trigger (make the recurrence earlier) the large one, or fast slip on the small one may be less visible according to the state of the surrounding stress field.

CONCLUSION AND PERSPECTIVE

This paper demonstrates the TOUGH2-BIEM simulator through simulations of stick-slip fault activation behavior, including aseismic and seismic slip. The stick-slip fault behavior is generated by aseismic slip that is activated by an internal pore pressure change due to injection. The simulation shows the occurrence

Figure 1 .

 1 Figure 1. Schematic illustration of TOUGH2-BIEM simulations of fluid driven faulting process. (left) An example of injection profile. (center) A model,500 m x 500 m with a width of 0.04 m, is prepared for TOUGH2 hydro-thermal simulation. The star represents an injection point and the square corresponds to a fault segment for BIEM faulting process modeling. (right) Three fault state conditions (A to C) in the BIEM simulation. Pore pressure change activates area B and the shear stress accumulates on area C.

Figure 2 .

 2 Figure 2. Snapshots of fault slip and shear stress change on the fault segment at three different times. Pore pressure change ( ), fault slip ( ) and shear stress change ( ) are shown on the right. Schematic illustration of TOUGH2-BIEM simulations of fluid driven faulting process. (left). Solid and broken lines correspond to small and large asperities of radius 5 m and 10 m, respectively.

Table 1 .

 1 Model parameters.

	Parameter	Quantity & Unit	Parameter	Quantity & Unit
	Initial Temperature	275°	Young's modulus	50 GPa
	Initial Pore Pressure	27.5 MPa	Frictional coefficient	0.6
	Porosity	0.5	Fault strength	0.4 MPa
	Medium density	2650 kg/m 3	Characteristic displacement	0.5, 1.0 mm
	Permeability	10 -14 m 2 -3.6 x 10 -12 m 2	Radius of asperity	5, 10 m

ACKNOWLEDGMENT

H.A thanks for his short stay at LBNL in autumn 2017 with the funding from Instituts Carnot. A part of the simulations was carried out at French National Supercomputing Center (GENCI/CINES) under the grant A0030406700 . Additional support was provided by the U.S. Department of Energy to the Lawrence Berkeley National Laboratory under contract No. DE-AC02-05CH11231.

of repeating stick-slip behavior on the fault segment, which is more frequently during the first 24 hours. The assumed governing equation (Equation ( 1)) is simple enough to test the framework of the simulation and to qualitatively demonstrate the fault activation behavior. It will be worth testing different relations, especially strong rate-dependent frictions. Systematic, parametric studies will allow us to compare the statistics of the repeating earthquake behaviors (their spatio-temporal patterns) to understand the physical relation governing the fault activation and the parameters as well as the hydraulic configuration surrounding the faults. The current study is applied on the stimulation test of deep geothermal experiment at a rather short time scale, but the framework is also applicable to other geological storage problems considering longer time scales.