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Northern France presents mostly a low level of seismic hazard according to the French national seismic hazard map. Despite low instrumental seismicity rates, strong and unfrequent historical earthquakes occurred, with for instance the M~6, 1580 Strait of Dover earthquake, or the M~5, 1896 Lens-Arras earthquake, whose seismogenic sources are presumably the Sangatte and the Marqueffles Faults, respectively. Both belong to the NW-SE-directed Weald-Boulonnais-Artois structure. Moreover, the Haubourdin Fault (also named Lille-Hazebrouck Fault), at the hinge of the Mélantois anticline, and bordering the southern edge of the Lille Metropolis (1.2 millions inhabitants), is considered as potentially active during Quaternary times. All these above-mentioned faults are linked to deep Paleozoic structures in the basement that formed along the northern front of the Variscan orogeny, and that were regularly reactivated during the Mesozoic and Cenozoic. To investigate and document the possible neotectonic activity of the Artois structure and the Haubourdin Fault, and therefore improve seismic hazard assessment in northern France, we used a pluridisciplinary approach based on the analysis of 1) LiDAR dataset, 2) paleoseismological trenching, 3) OSL/14C dating, and 4) sub-surface geophysical survey.Along the Artois structure, we focused on the locality of Harnes within Lens city suburbs. A preventive archeological work unraveled a clear sub-surface deformation feature that we analyzed through several ~2m-deep trenches. Field investigations indicated that the fault presents a regular N130° strike, which is consistent with surface and subsurface regional structures, and a 25-30° southwestward dip. Reverse throw along the fault were measured to about 15-20 cm thanks to a clearly displaced coal-rich horizon, sampled for C-14 dating. Interpretation of the data is complex since the site is located in a region where glacio-tectonic processes, severe First World War bombing and subsidence due to underground mining are documented.Along the Haubourdin Fault, our analysis of high resolution LiDAR data highlighted two topographic scarps aligned along a N110°E trend, but that do not match with the fault trace extracted from the geological map. This new fault trace is confirmed by subsurface geophysical survey (electric resistivity tomography and mapping). Both scarps present contrasted uplifted blocks since the southern block is uplifted (by several meters) for the western branch, whereas the northern block is uplifted (by 1-2 m) for the eastern branch. All these new field mapping results call for a substantial revision of the fault trace in the region together with a consideration of its segmentation. Finally, two new OSL datings has been obtained from a sandy-clay layer unconformably sealing some Late Paleocene deformation in the southern Lille suburb (i.e., Villeneuve d’Ascq). It gives the first minimum age in the literature for the deformation of the Mélantois northern limb.

The North Anatolian Fault (NAF) is one of the major active structures in the Eastern Mediterranean. Its right-lateral strike-slip fault initiated in eastern Turkey 13 Ma ago. The NAF westward propagation during Neogene and Quaternary times delineates the plate boundary between Eurasia and Anatolia-Aegean. The western termination of NAF is currently located in the North Aegean Trough (NAT) where NAF displays a NE-SW direction. In the NAT, the NAF termination is located near to the Sporades Islands. In the western prolongation of this termination, there is a wide domain characterised by distributed deformation. This major extensional area is mainly constituted by the Corinth rift and the North Evia domain, our study area. The whole zone experience a relative high seismicity with strike-slip focal mechanisms, especially right-lateral displacements along NE-SW-striking faults, which are mainly located between the North Evia domain and the Southern Thessaly. Our study is mostly based on new very-high-resolution seismic reflection profiles (Sparker) acquired during the WATER surveys (Western Aegean Tectonic Evolution and Reactivations) in July-August 2017 and 2021, onboard the R/V “Téthys II”. We also analysed several seismicity catalogues in order to connect the recent structures from seismic lines to active tectonics over the region. The interpretations from these datasets emphasize the evolution of the deformation of the North Evia domain, in particular, along the NE-SW striking lineament “Lichades Area – Oreoi Channel – Skiathos Basin” (L-O-S). The deformation in the Lichades Area is dominated by numerous active normal faults striking W-E or WNW-ESE and showing metric-scale offsets (up to 5 m.) within the Holocene sequence. One of the largest sub-active to active fault is striking NE-SW, parallel to the Oreoi Channel, and thus strongly oblique to the main rift deformation. The Oreoi Channel is a marine straight linking the Lichades Area and the Skiathos Basin. The seismic profiles highlight normal faults of different ages with a NE-SW direction. In the south-east, the Oreoi Channel is delineated by the Oreoi Fault, a mainly onshore normal fault which is dipping towards north-west. The Skiathos Basin is a newly discovered structure from our seismic dataset that is separated from the Skopelos Basin by a NE-SW striking acoustic ridge. The Skiathos Basin presents two main depocenters individualized by areas of rising acoustic basement. Some normal faults, oriented NE-SW and W-E, have been identified in the basin. Finally, many earthquakes focal mechanisms located in the Skiathos Basin and the Oreoi Channel indicate strike-slip faulting, with a right-lateral motion along the NE-SW direction. This detailed structural analysis together with the synthesis of seismic activity allow to propose a tectonic map with new insights on the recent deformation of the key-area “L-O-S” in the south-western prolongation of NAF. The Skiathos basin development shows indications of transtensive deformation. The Oreoi Channel is controlled by NE-SW-striking faults with a right-lateral component and the Lichades Area displays several fault with oblique direction and pure extension. We propose that the L-O-S tectonic system prolongs the NAF system and may progressively evolve as the future plate boundary.

Deformation process and strength evolution in accretionary wedges are important factors that affect kinematics and dynamics at subduction zones. However, it is still challenging to understand the relationship between the short-term geodetic observations (coupling ratios or earthquakes) and the long-term geological structures (patterns of imbricated thrust sheets or fault networks) in natural systems. In this study, we performed 2-D, large-shortening (1 m) analog sandbox experiments to examine how the wedge deformation is affected by different décollement conditions including heterogeneities and numbers of weak layers in the incoming sediment. Four different settings (Types 1–4) of the incoming sediment layers were examined in this study. Serial side-view digital photographs were quantitatively analyzed with an open-source DIC software to characterize the accretion cycles, underthrusting/underplating, and reactivation of pre-existing thrusts (out-of-sequence thrusts).The reference models with single décollement (Type1) were dominated by periodic cycles of frontal accretion with landward propagation of strain, uplift, and reactivation of the pre-existing thrusts, which progressively increased in strength and then approached the critical state. Each cycle was composed of preparation (Phase 0), initiation (Phase 1), accretion (Phase 2), and reactivation (Phase 3). Through frontal accretion, the wedge accumulated the strain internally with landward migration of the basal coupled area along the plate interface, which caused uplift and reactivation of the landward preexisting thrusts in the wedge (hardening). When a new frontal thrust emerged at the deformation front (Phase 1), the basal coupling was suddenly lost (softening). Through this cycle, the entire accretionary wedge progressively increased in strength while experiencing hardening and softening and approached the critical state. The double décollement models (Type 2) showed a similar accretion cycle to Type 1 models, but it consisted of a combination of shallow-rooted and deep-rooted frontal thrusts, meaning that the décollement stepped up and down between the interbedded and basal weak layers. This promoted sediment underthrusting at the frontal part of the wedge during the early phase of the accretion cycle and favored the connection of pre-existing deep-rooted thrusts with shallow-rooted thrusts. A frictional interruption in the basal décollement (Type 3 or 4 models) produced a combination of a steep-taper inner wedge and a gentle-taper outer wedge, and disturbed the wavelengths of the accretion cycle. The single décollement models (Type 3) were dominated by high-angle out-of-sequence thrusts, while underplating was significantly promoted in the double décollement model (Type 4) where the interbedded décollement acted as a low-angle, smooth-surface megathrust.These results shed light on the impact of properties and homogeneity of the incoming sediment and the plate interface on the spatial and temporal evolution of internal structure and thrust activity in accretionary wedges through multiple accretion cycles. Comparisons of our results with natural subduction zones will contribute to understanding the mechanisms and dynamics of deformation process and strength evolution in natural subduction zones.

The Eastern Sardinian margin consists in a hyper-extended rifted margin, located in the western Tyrrhenian Sea, a recent back-arc basin (late Neogene). This area was affected by strong aerial erosion during the Messinian Salinity Crisis (MSC, 5.96 – 5.33 My) associated with the drop of sea level (> 1500 m) which occurred throughout the whole Mediterranean. The Gulf of Orosei and surrounding offshore areas are characterized by small and diffuse drainage systems input, where the Messinian Erosion Surface (MES) has rarely been studied while it has been in large fluvial systems (Rhone, Ebro). The MES was already found in the Cendrino valley (which flows in the Gulf) and in the East-Sardinia Basin but the link between onshore and offshore was never been studied in the area. The “METYSS 4” cruise (June 2019, R/V “Téthys II”) allowed acquiring more than 2000 km of very high-resolution (VHR) seismic data (Sparker), following a dense grid (1.5 km average profile spacing), on the Eastern Sardinian continental shelf, and especially in the Orosei Gulf area, that has been little explored until now. While the main limitation on seismic data (air-gun) interpretation is often due to the occurrence of sea bottom multiple, the limitation for Sparker data may also be due to very short shot intervals at greater water depth. The seismic trace ends where there still is signal of interest. Thus, we applied a simple method to increase investigation depth for short shot intervals (0.333 - 0.533 ms), which allowed interpretation on the continental slope. This approach consists in copying the raw data and concatenating the copied data under the raw data with a shift of 1 shot point. To constrain the MES depth on the continental slope and shelf we compared air-gun seismic data from previous METYSS surveys, where the MES has already been interpreted by a strong erosional discordance between Plio-Quaternary deposits and pre-MSC units, with the new VHR data. The restoration of the morphological features of the Orosei canyon at Messinian times shows that the former Messinian canyon network is very similar to the present-day one. The present-day canyon and its tributaries show sub-marine erosion in the talwegs. The heads of the canyons present gravitational features, highlighted by chaotic deposits near the talweg of the canyon or in-between the Plio-Quaternary strata. Offshore Arbatax, south Orosei, the seismic profiles show no significant Plio-Quaternary deposits (thickness < 0.1 sTWT), which allows polygenic pre-MSC units to occur at the seafloor. In the Gulf, we observe thick deposits (0.4 - 0.5 sTWT) on the right bank of Orosei Canyon, making it more complicated to image the MES in this area. The sedimentation rate on this margin is very low (c.a. 9 cm/ka in the Gulf of Orosei), which is consistent with previous studies on the East-Sardinian basin (3-20 cm/ka). These preliminary results will allow correlating for the first time the MES distribution from the onshore to the offshore continental slope of the Eastern Sardinian Margin in order to improve the MSC understanding in this key area.

Taphonomic analysis is a useful tool to assess the intensity of alteration of skeletal remains and to help characterize depositional conditions as well as completeness and resolution of fossil assemblages. We herein introduce TAPHOGRAPH, an Excel spreadsheet script (a R code is also available), for the production of taphonomic diagrams to characterize the taphonomy of skeletal remains. The graphical representation depicts four taphonomic factors (fragmentation, abrasion, bioerosion, and encrustation) as a cumulative curve that allows visualization and comparison of the degree and variability of taphonomic alteration for different hard part types from one or more samples in a single diagram. The TAPHOGRAPH methodology is highly flexible, and can be used to assess the relative influence of mechanical versus biological (versus chemical) taphonomic alteration. The TAPHOGRAPH approach can guide inferences about hydraulic regimes, residence time at the seafloor, and intensity of different taphonomic processes.

The Balearic Promontory (Spain) is of key importance to understand the tectonic kinematics of the westernmost Mediterranean, because its continued marine sedimentation has recorded the contrasting effects expected from competing geodynamic models proposed for the region. Near the center of this promontory, between the islands of Mallorca and Ibiza, the Miocene to Pleistocene stratigraphy of the Central Mallorca Depression presents an ideal record of the tectonic deformation that has received only limited attention. We use a widespread dataset of 2D seismic reflection profiles to identify, interpret and map the main prominent reflectors and extrapolate the thickness of the pre-Messinian and Pliocene-Quaternary sedimentary units. We then quantify the timing and style of deformation related to the various fault systems. Our results reveal for the first time a series of aligned small depressions bounded by extensional and strike-slip faults and filled with Plio-Quaternary sediment, perfectly aligned with the sub-basins of the onshore Mallorca Graben. A subsidence analysis confirms this correlation. We identify non-cylindrical deformation within the Plio-Quaternary unit that is remarkably similar to that observed onshore, suggesting continuous fault zones from the Central Mallorca Depression to Mallorca Island. We interpret an intra-PQ unconformity as the marker of a transition from extensional to strike-slip tectonic regime. The strike-slip stage is represented by both transpressional and transtensional structures, interpreted as restraining/releasing bends respectively and step overs along the faults. We show that these offshore faults in the Central Mallorca Depression overlap well with seismic epicenters and suggest major active strike-slip corridors that have an onshore continuity both until eastern Mallorca and in the southwestern Ibiza margin. The role of previous tectonic inherited structures (rifting, Betic thrusts, post-orogenic collapse) on the deformation reported here is discussed and we propose a tentative sketch that integrates our results in a Miocene to Present-day evolution at regional scale., This research is partly carried out under the SALTGIANT ETN, a European project funded by the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement number 765256. SALTGIANT ESRs and PIs are all thanked for the numerous exchanged discussions and comments during workshops, courses and fieldtrips. We are grateful to Antonio Cap? and Juan Forn?s for inspiring discussions on arguments about the study area. Part of the seismic data covering the Balearic Promontory and shown in this work were provided courtesy of WesternGeco and Spectrum companies that we acknowledge. We acknowledge Schlumberger Company for providing the academic license of the seismic interpretation software Petrel. The authors are grateful to Guillermo Booth-Rea and Rob Govers whose reviews and suggestions greatly improved the original manuscript. This paper is dedicated to our colleague Guillem Mas who suddenly and dramatically passed away during the writing of the manuscript. He showed us the field in Mallorca in 2019, where the idea of this work came from.

A new graphical representation of the taphonomy of skeletal carbonates observed at the thin-section scale is proposed, demonstrating their utility in drawing information about the effects of early sea-floor processes on the post-mortem fate of fossil hard parts. The graphical representations consist of two-axis diagrams, which integrate the degree of fragmentation, abrasion, bioerosion, and encrustation as primary descriptors of the average state of fossil remains in a Miocene limestone section from southeastern North Island of New Zealand. Numerical values are expressed as percentages that represent the contribution of each factor to alteration (i.e., the four factors represent up to 25% each of the total alteration), the sum of values quantifying the amount of departure from pristine condition. Data are plotted in a cumulative form that reflects synergistic action of sea-floor processes towards hard parts destruction. One important virtue of this graphical representation is that the nature, degree, and variability of taphonomic alteration can be visualized and compared in a single diagram for several grain categories within a sample, and between samples. The proposed scheme is particularly flexible because more than four taphonomic categories can be integrated, independently from the number of alteration classes specific to each category, provided conversion of scores obtained in each taphonomic categories into percentages. Compiled results of such taphonomic analyses could be used in the future to identify specific depositional conditions, such as hydraulic regime, transportation, and residence time on the sea floor (a potential proxy to net accumulation rates).

Among other parameters, volcanic activity adjacent to shallow marine environments influences the development of ecosystems and their carbonate-producing communities. Volcaniclastic sediment influx in particular has potential to cause rapid and drastic environmental changes affecting biological systems in their composition and activity, and ultimately leading to changes to and breaks in carbonate sedimentation. Such sedimentary breaks that form in response to volcanic processes are rarely described in detail despite the common occurrence of carbonate platforms adjacent to active volcanoes both in the recent and past geological record. The Island of St. Bartholomew (St. Barths), French West Indies, exposes sections of middle Eocene limestones intercalated with thick volcaniclastic deposits and lavas. Theses carbonates provide an example of a low-latitude tropical platform where non-framework building biota were important, if not dominant, sediment contributors. The carbonate system records the repeated collapse and renewal of carbonate production, as a result of episodic volcaniclastic material input. The discontinuous nature of the carbonate sedimentation is reflected in contrasted depositional systems across sedimentary surfaces and gradational contacts. The studied Eocene deposits provide a sedimentary record of how volcanic events impacted warm-water carbonate factories, both in their disturbance, demise and recovery.

The Anatolia-Aegean microplate is currently extruding toward the South and the South-West. This extrusion is classically attributed to the southward retreat of the Aegean subduction zone together with the northward displacement of the Arabian plate. The displacement of Aegean-Anatolian block relative to Eurasia is accommodated by dextral motion along the North Anatolian Fault (NAF), with current slip rates of about 20 mm/yr. The NAF is propagating westward within the North Aegean domain where it gets separated into two main branches, one of them bordering the North Aegean Trough (NAT). This particular context is responsible for dextral and normal stress regimes between the Aegean plate and the Eurasian plate. South-West of the NAT, there is no identified major faults in the continuity of the NAF major branch and the plate boundary deformation is apparently distributed within a wide domain. This area is characterised by slip rates of 20 to 25 mm/yr relative to Eurasian plate but also by clockwise rotation of about 10° since ca 4 Myr. It constitutes a major extensional area involving three large rift basins: the Corinth Gulf, the Almiros Basin and the Sperchios-North Evia Gulf. The latter develops in the axis of the western termination of the NAT, and is therefore a key area to understand the present-day dynamics and the evolution of deformation within this diffuse plate boundary area.Our study is mainly based on new structural data from field analysis and from very high resolution seismic reflexion profiles (Sparker 50-300 Joules) acquired during the WATER survey in July-August 2017 onboard the R/V “Téthys II”, but also on existing data on recent to active tectonics (i.e. earthquakes distribution, focal mechanisms, GPS data, etc.). The results from our new marine data emphasize the structural organisation and the evolution of the deformation within the North Evia region, SW of the NAT.The combination of our structural analysis (offshore and onshore data) with available data on active/recent deformation led us to define several structural domains within the North Evia region, at the western termination of the North Anatolian Fault. The North Evia Gulf shows four main fault zones, among them the Central Basin Fault Zone (CBFZ) which is obliquely cross-cutting the rift basin and represents the continuity of the onshore Kamena Vourla - Arkitsa Fault System (KVAFS). Other major fault zones, such as the Aedipsos Politika Fault System (APFS) and the Melouna Fault Zone (MFZ) played an important role in the rift initiation but evolved recently with a left-lateral strike-slip motion. Moreover, our seismic dataset allowed to identify several faults in the Skopelos Basin including a large NW-dipping fault which affects the bathymetry and shows an important total vertical offset (>300m). Finally, we propose an update of the deformation pattern in the North Evia region including two lineaments with dextral motion that extend southwestward the North Anatolian Fault system into the Oreoi Channel and the Skopelos Basin. Moreover, the North Evia Gulf domain is dominated by active N-S extension and sinistral reactivation of former large normal faults.

The Sperchios - North Evia Gulf rift system is WNW-ESE directed and participates to the widespread crustal extension induced by the respectively southward and south-westward Nubian and Ionian slabs retreat, and by the extrusion of the Anatolia-Aegean microplate. This crustal stretching, active at least since the early Pliocene, is partly coeval with the North Anatolian Fault (NAF) propagation through the Marmara Sea and the North Aegean domain. At the western termination of the NAF, in the studied area, the domain is widely heterogeneous as it has been previously deformed by successive tectonic events during Hellenic orogeny, from Middle Jurassic to Paleogene times. The low elevation of the Internal Zones in respect to the External Zones of Hellenides suggest that the Frontal Thrust of the Internal Zones, that crosscut the Sperchios Rift, plays a major role in the distribution of rift systems within that area. The Sperchios-North Evia Gulf rift developed over the internal Zones and was driven by at least two major extensional episodes. The first one is characterised by a NNE-SSW extensional direction while the second, still active, is NNW-SSE to N-S. This change in direction can be associated to a modification of the tectonic setting within the Aegean Plate or can be a consequence of clockwise rotation of the whole western Aegean domain.The WATER survey (Western Aegean Tectonic Evolution and Reactivations), conducted in July-August 2017 onboard the R/V “Téthys II”, allowed to acquire more than 1300 km of very high resolution seismic reflection profiles (Sparker 50-300 Joules) around North Evia Island (North Evia Gulf, Oreoi Channel and Skopelos Basin). The new dataset issued from this survey illustrates structural patterns that can be correlated with onland fault systems.The interpretation of this new seismic data allowed us to precise the main trends of the North Evia Gulf rift deformation. For example, the rift bordering faults show rapid longitudinal changes in terms of offsets and of their main tilting polarity. Our structural analysis results, together with the kinematic analysis of onshore fault zones, give detailed constraints on the rift structural organisation as well as on the relative chronology of tectonic episodes.Furthermore, these results provide important data in order to discuss the relations of some major rift structures with other crustal structures inherited from earlier deformation in the Hellenides, and also to consider the deformation patterns in the south-western prolongation of the North Anatolian Fault system during Pliocene to Quaternary times. We discuss the relations between various generations of crustal-scale structures and propose that the variations in the rift asymmetry were triggered, during its initial development, by the presence of older crustal heterogeneities.

The METYSS project (Messinian Event in the Tyrrhenian from Seismic Study) is based on high-resolution seismic data acquired along the Eastern Sardinian margin. The main aim is to study the Messinian Salinity Crisis (MSC) in the Western Tyrrhenian Basin, but we also investigated the thinning processes of the continental crust and the timing of crustal vertical movements across this backarc domain. Our first results shown that rifting ended before the MSC, but that crustal activity persisted long after the end of the rifting. This has been particularly observed on the proximal margin, the East-Sardinia Basin, where the Mobile Unit (MU, mobile Messinian salt) is thin or absent. In this study, we examined the distal margin, the Cornaglia Terrace, where the MU accumulated during the MSC and acted as a décollement, thus potentially decoupling the basement from the sedimentary cover. Our observations provide evidence for lateral flow and gravity gliding of the salt and its brittle sedimentary overburden along local basement slopes generated by the post-MSC tilting of some basement blocks formerly generated during the rifting. We also investigated an intriguing wedge-shaped body of MU located in a narrow N-S half graben bounded to the west by a major, east-dipping, crustal normal fault. Classically, one could think that this salt wedge is related to the syn-tectonics deposition of the MU, but we propose an original scenario, in which the post-rift vertical motion of the major fault has been cushioned by lateral flow of an initially tabular salt layer, leaving the supra-salt series apparently unaffected by the crustal motions of the basement. We tested this scenario by comparing natural data and physical (analogue) modelling data. Our results reveal that salt tectonics provides a powerful tool to understand the deep crustal tectonics of the margin and to constrain the timing of vertical motions in the Western Tyrrhenian Basin, results that can be applied to rifted salt-bearing margins worldwide.

International audience

The rifting of the Eastern Sardinian margin is considered to have occurred during the Neogene, by back-arc extension related to the eastward migration of the Apennine subduction system, leading to the development of the Tyrrhenian Basin, Western Mediterranean Sea. The locus of the extension during the rifting is interpreted to have occurred first in the East-Sardinia Basin (proximal margin), and then in the Cornaglia Terrace (distal margin). However, the dynamics of the Western Tyrrhenian Basin during the rifting is still largely undated, and the kinematics of the development of the different domains of the Eastern Sardinian margin remains poorly understood. This is due to the sparsity of dated rock samples within the basin, mainly recovered locally during ODP Leg 103, and because the timing of activity of the structures of the basin has been addressed so far using regional data, whose resolution is insufficient to observe the timing of the extension at the scale of a fault plane.In this study, we use a 2400 km-long high-resolution seismic-reflection dataset acquired along the Eastern Sardinian margin during the “METYSS” research cruises in 2009 and 2011, and specifically designed to observe the block-bounding faults and the syn-rift and post-rift units. We interpret the syn-tectonic markers of the crustal deformation across the Eastern Sardinian margin, and we use the seismic markers of the Messinian Salinity Crisis (MSC) that provide exceptional and accurate natural time markers, to estimate the age of faults development and understand their evolution within the Western Tyrrhenian Basin.Our observations demonstrate that the rifting was polyphased across the Western Tyrrhenian Basin, and that syn-rift extension was active on the proximal margin long before the MSC, whereas the distal Cornaglia Terrace developed only a short time before the MSC. Surprisingly, our interpretations also evidence significant post-rift reactivation of some structures of the Eastern Sardinian margin. These reactivations, formerly considered to be very minor or absent in the Western Tyrrhenian Basin, started in the Pliocene and occurred up to very-recent times along local fault-planes, as shown by the deformation of the shallowest Pleistocene layers and the seafloor.Our results permit to precise the timing of the syn-rift and post-rift evolution of the Eastern Sardinian margin. Given the rarity of natural time makers in offshore sedimentary basins to address the dynamics of basins development, we expect our results to provide useful comparisons to study the kinematics of extension at other back-arc basins worldwide.

The METYSS project (Messinian Event in the Tyrrhenian from Seismic Study) is based on high-resolution seismic data acquired along the Eastern Sardinian margin, Western Tyrrhenian Sea. The main aim is to study the Messinian Salinity Crisis (MSC) in the Western Tyrrhenian Basin, but we also investigated the thinning processes of the continental crust and the timing of crustal vertical movements across this backarc domain. Our first results shown that rifting ended before the MSC, but that crustal activity persisted long after the end of the rifting. This has been particularly observed on the proximal margin, the East-Sardinia Basin, where the Mobile Unit (MU, mobile Messinian salt) is thin or absent. In this study, we examined the distal margin, the Cornaglia Terrace, where the MU accumulated during the MSC and acted as a decollement, thus potentially decoupling the basement from the sedimentary cover. Our observations provide evidence for lateral flow and gravity gliding of the salt and its brittle sedimentary overburden along local basement slopes generated by the post-MSC tilting of some basement blocks formerly generated during the rifting. We also investigated an intriguing wedge-shaped body of MU located in a narrow N-S half graben bounded to the west by a major, east-dipping, crustal normal fault. Classically, one could think that this salt wedge is related to the syn-tectonics deposition of the MU, but we propose an original scenario, in which the post-rift vertical motion of the major fault has been cushioned by lateral flow of an initially tabular salt layer, leaving the supra-salt series apparently unaffected by the crustal motions of the basement. We tested this scenario by comparing natural data and physical (analogue) modelling data. Our results reveal that salt tectonics provides a powerful tool to understand the deep crustal tectonics of the margin and to constrain the timing of vertical motions in the Western Tyrrhenian Basin, results that can be applied to rifted salt-bearing margins worldwide.

International audience; In the last fifty years, the Messinian Salinity Crisis (MSC) has been widely investigated in the Mediterranean Sea, but a major basin remains fewly explored in terms of MSC thematic: the Western Tyrrhenian Basin. The rifting of this back-arc basin is considered to occur between the Middle-Miocene and the Early-Pliocene, thus including the MSC, giving a unique opportunity to study the crisis in a context of active geodynamics. However the MSC seismic markers in the Western part of the Tyrrhenian Sea have only been investigated in the early eighties and the MSC event in the Western Tyrrhenian Basin remains poorly studied and unclear.In this study, we revisit the MSC in the Western Tyrrhenian Basin, i.e. along the Eastern Sardinian margin. We present results from the interpretation of a 2400 km long HR seismic-reflection dataset, acquired along the margin during the “METYSS” research cruises in 2009 and 2011. The maps of the MSC seismic markers reveal that the Eastern Sardinian margin was already dissected in structurals highs and lows during the MSC. We also demonstrate that the MSC markers constitute powerfull time-markers to refine the age of the rifting, which ended earlier than expected in the East-Sardinian Basin and the Cornaglia Terrace. These results allow us to discuss the palaeo water-depth of the Western Tyrrhenian Basin during the MSC, as well as implications for possibles scenarios of the Messinian Salinity Crisis across the Eastern Sardinian margin

Language learners have access to a wide range of tools for communication and interaction through networks, where multiple options exist for creating meaning. This chapter introduces the study of such multimodal meaning‐making for language learning. The study of meaning‐making through the use of technology for mediation has been pursued since the technology became widespread. An overview of multimodality in interaction is offered in the introduction to a Special Issue of Semiotica by Stivers and Sidnell (2005); for multimodality in communication, see Kress (2010); for multimodality in classroom‐based language learning, see Royce (2007) and Budach (2013); for a discussion of digital mediation see Jones and Hafner (2012), and for a summary about technology‐mediated language learning see Hampel (2012). These sources provide a starting point for the investigation of multimodality in language learning, which is relatively recent computer‐assisted language learning (CALL) research. In view of the importance of such meaning‐making resources for learning, this chapter introduces the meaning of “mode” and “multimodality” before introducing the research and theoretical issues in the study of multimodality in language learning. It then describes a corpus‐based approach for studying multimodality in CALL, drawing attention to important methodological factors such as transcription that come into play in conducting such research.

International audience; The investigation of outcrop analogues using Unmanned Aerial Vehicle (UAV) has become increasingly popular to improve the understanding of subsurface heterogeneity. Although seismic data offer an invaluable method to characterize the stratigraphic architecture of deep-water systems and therefore help unlock their reservoir potential, the scale of observations cannot capture detailed vertical extent of the sediment distribution and the related processes responsible for the deposits. This work uses a combination of photographic data acquired from a UAV using Ground Control Points, and traditional fieldwork data to better characterize the gravity-driven systems of the Hikurangi subduction wedge (North Island, New Zealand). Their best onshore expressions are found along the coastline: a challenging working environment which evolves every day leading to multiple acquisitions (tides will affect wind variation and wave action, impacting sand coverage; sun and clouds will impact light exposure). It is therefore essential to adapt the way we acquire and model data to ensure that all the information are gathered into one single comprehensive model. Our study proposes to expand on the traditional Structure from Motion workflow to account for such settings and help create more accurate models. We will present this approach applied to three different coastal outcrops. \textcopyright EAGE 2019.

International audience; Major ophiolitic thrust sheets are widespread within the internal Hellenides, particularly in the Pelagonian domain (Greece and Albania). The ophiolitic sheets are notably well exposed in western Othris mountains of continental Greece. In that area, the structural stacking of oceanic nappes obducted in the Jurassic is particularly well constrained. New sedimentological and structural data from recently studied outcrops, together with new micropaleontological data, allow to reconsider the architecture of the ophiolitic nappes and their evolution in the Othris mountains. Our new data set includes notably the description of a Mid-Late Jurassic sedimentary succession, from basal litharenites and radiolarites to syn-obduction mélange, on top of the uppermost Mega Isoma ophiolitic Unit. These results are crucial in the perspective of constraining the Jurassic contractional evolution of the Maliac Ocean from the beginning of the subduction and intra-oceanic obduction to the final obduction on the Pelagonian continental crust. Another major result concerns the dating of primary conformable series of Middle and Late Triassic age on top of the pillow-lavas of the Fourka unit. Since this lava unit, with MORB affinities, is one of the syn-obduction Jurassic nappes, we propose that this very large Fourka nappe represents the major reference unit of the initial (Triassic) Maliac oceanic crust.; Des nappes ophiolitiques importantes caractérisent les Hellénides internes, notamment le domaine Pélagonien en Grèce et en Albanie. C'est le cas dans les montagnes d'Othrys, en Grèce continentale, où l'empilement des nappes ophiolitiques obduites au Jurassique est particulièrement bien contraint. Des données sédimentologiques et structurales acquises à la faveur de nouveaux affleurements, sur les principales nappes ophiolitiques d'Othrys occidentale, couplées à de nouvelles déterminations de microfossiles, permettent de préciser la nature et la mise en place de ces nappes. Nous décrivons notamment, pour la première fois, une série du Jurassique moyen-supérieur constituant la couverture sédimentaire océanique de l'importante unité ophiolitique de Méga Isoma. Cette série, constituée de litharénites et de radiolarites à la base, se termine par une formation syn-obduction de type mélange à blocs. Ces résultats s'avèrent être déterminants s'agissant de mieux contraindre les processus océaniques syn-convergence d'âge jurassique au sein de l'océan Maliaque entre le début de la subduction et de l'obduction intra-océanique jusque l'obduction finale sur la croûte continentale Pélagonienne. Un autre résultat majeur est l'obtention exclusive de datations du Trias moyen et supérieur sur les séries radiolaritiques reposant en contact stratigraphique indubitable sur les pillow-lavas de l'unité de Fourka. Cette unité triasique étant riche en laves de type MORB et présente au coeur de l'empilement jurassique de nappes syn-obduction, nous proposons de faire de cette unité de Fourka l'unité de référence de la croûte océanique initiale (triasique) de l'océan Maliaque.

The North Anatolian Fault Zone (NAFZ) is one of the most hazardous active faults on Earth, yet its Pliocene space-time propagation across the north Aegean domain remains poorly constrained. We use low-temperature multi-thermochronology and inverse thermal modelling to quantify the cooling history of the upper crust across the Olympus range. This range is located in the footwall of a system of normal faults traditionally interpreted as resulting from superposed Middle–Late Miocene N–S stretching, related to the back-arc extension of the Hellenic subduction zone, and a Pliocene-Quaternary transtensional field, attributed to the south-westward propagation of the NAFZ. We find that accelerated exhumational cooling occurred between 12 and 6 Ma at rates of 15–35 °C Ma−1 and decreased to

Well-preserved Late Norian Radiolaria were extracted from two pebbles of radiolarian chert included in Lower Miocene conglomerates of the Pentalofos Formation, in the area of Meteora (Mesohellenic basin, Greece). Both samples yielded a similar assemblage characterized by the presence of species Betraccium deweveri PESSAGNO & BLOME, Bipedis acrostylus BRAGIN, Pylostephanidium ankaraense BRAGIN & TEKIN and several other taxa typical of the Betraccium deweveri zone (uppermost Norian). This is the first evidence of Upper Norian radiolarian cherts from Greece. It is likely that the studied chert pebbles were derived from ophiolitic complexes or distal continental margin series situated to the east of the Mesohellenic basin; they were part of the Upper Norian oceanic realm that was obducted, during the Late Jurassic, over the Pelagonian continental crust. During the Late Miocene they were still present east of Meteora and they have been eroded since.

This paper reports on a study of the interactions between text chat and audio modalities in L2 interaction in a synthetic (virtual) world and observes whether the text chat modality was used for corrective feedback and the characteristics of the latter. This is examined within the context of a hybrid Content and Language Integrated Learning design workshop. This course involved 17 students of architecture whose L2 was either French or English and for which the synthetic world environment Second Life was employed for distance language sessions. Using multimodal transcriptions of the interaction data from these sessions, it was found that text chat was employed for content-based interaction concerning the task as well as feedback concerning non-target-like errors in the audio modality. Feedback predominantly concerned lexical errors and was offered in the form of recasts. The multimodality of the environment did not appear to cognitively overload students who frequently responded in the audio modality to corrective feedback offered in the text chat. The study highlights the need to train language tutors who wish to exploit synthetic worlds to use the text chat in parallel with the audio to support learners' verbal production with respect to verbal participation and proficiency.

Ophiolitic bodies in the Dinaro-Hellenic mountain belt are among the most important ones in the Peri-Mediterranean Alpine chains. The characteristic feature of this ophiolitic belt is its Middle to Late Jurassic age of obduction. The ophiolitic bodies form two major belts on each side of the Pelagonian zone: an east Pelagonian belt in the Vardarian domain and a Supra-Pelagonian ophiolitic belt (SPO) to the west. The different hypotheses relative to the origin of the SPO present geodynamic evolution models accounting for most of the available data: a mid-Triassic episode of rifting; a Ladinian–Jurassic episode of sea-floor spreading forming notably the Maliac Ocean; a Middle to Late Jurassic convergent period with subduction and obduction episodes, and finally, a late episode of Tertiary compressional deformation responsible for the westward thrusting of the Jurassic ophiolitic nappes over the external zones. Despite many studies dating from the early 1970s, the eastern or western Pelagonian origin of these ophiolites, especially the SPO, is still under dispute. Whatever the adopted hypothesis, we consider that the main SPO bodies (N-Pindos, Vourinos, Othris, Evia, Argolis) have the same origin because of their geographic continuity and of the similarities in their geological characteristics. We propose that this ocean corresponds everywhere to the Maliac Ocean, defined in Othris from the well-preserved sedimentary (oceanic margin) and ophiolitic nappes thrust during the Late Jurassic obduction onto the Pelagonian platform. There is strong evidence for the existence of two deep basins on both sides of the Pelagonian continental ridge during Triassic–Jurassic times. They correspond, respectively, to the Vardar area to the east and the Pindos domain to the west, one of these domains being at the origin of the SPO. The hypothesis of an eastward emplacement of the SPO from the Pindos domain is based mainly on sedimentological data from the margin series and on structural analyses of ophiolitic bodies. However, we conclude the westward obduction of the Maliac Ocean, originating from the Vardar area, to be the best fitting model. This westward model is supported by paleogeographic and structural constraints on regional scale. Notably, the absence of obducted ophiolites in the Jurassic series of the Koziakas units (units attributed to the western Pelagonian margin) and of the Parnassus domain (on the eastern side of the Pindos basin) is difficult to reconcile with an eastward obduction from the Pindos domain. Other observations, such as the distribution of ophiolitic detritus in the internal and external zones, also promote the westward Late Jurassic obduction of the Maliac Ocean. Our preferred model offers a consistent explanation for the mechanism and timing of the emplacement of the SPO, as well as providing insight on the origin and emplacement of the Vardarian ophiolites. Following this hypothesis, there is no need for a clear boundary between the SPO and the west Vardarian ophiolitic bodies as they were obducted from the same oceanic basin and during the same Jurassic tectonic event. In this paper, we develop evidence in favor of the eastern Pelagonian origin for the SPO (our adopted model) and provide discussion on the data supporting the main alternative hypothesis (western origin for the SPO).

Background: Cancer is an established risk factor for venous thromboembolism (VTE) and the incidence of cancer increases in the elderly. The benefit of screening for occult cancers in this population is still not clear. Aim: To evaluate a systematic screening programme for cancer in elderly patients with VTE. Methods: This was a prospective study with a 12-month follow-up period. It was conducted in a single centre in consecutive patients over the age of 70 years who had a confirmed diagnosis of VTE. Predefined non-invasive screening techniques for cancer with clinical, laboratory (including tumour markers) and radiological investigations (abdominal ultrasound, chest X-ray and a thoraco-abdominopelvic computed tomography scan) were evaluated. Results: Fifty patients with a median age of 80 years (range: 70 to 94 years) were included. One patient was diagnosed with chronic lymphocytic leukaemia at inclusion and cancers were found in three other patients during the follow-up period (rectosigmoid adenocarcinoma with hepatic metastases, hepatocellular carcinoma and gastric adenocarcinoma). Only one of the four cancers could have been treated at an earlier stage. The mortality rate of the entire cohort after 12 months was 28%. Two patients died as a direct consequence of cancer. Discussion: In this study of elderly patients, a non-invasive screening strategy did not detect several cancers that were subsequently overt clinically. A full history, clinical examination and routine laboratory investigations might be the optimal first-line strategy to detect cancer after the diagnosis of VTE in elderly patients, but regular clinical examinations during follow up are warranted.

The Meteora are a famous sightseeing area of northern Greece, namely for the monasteries culminating at the strange pinnacles surrounded by impressive cliffs made of a stack of conglomeratic fan deltas from the Lower Miocene. This paper analyzes the imprint on their stratigraphy of regional deformation related to the subduction of the external zones beneath the Mesohellenic basin (MHB). The onset of deposition of the Meteora series corresponds to a major change in depositional regime (from marls to conglomerates) that can be followed throughout the MHB. The tectonic control on that change is supported by both sedimentological and structural characteristics, such as the progressive tilting of topset dip within the fan-deltas, the input of large volumes of pebbles derived from areas of rapidly renewed reliefs to the east of the Meteora (Pelagonian indentor), and the partitioning of two successive Meteora depocentres apart from a large faulted anticline (Theopetra-Theotokos structure). Most of the recorded deformation corresponds to vertical movements, with the local development of early Miocene synsedimentary normal faults.

New Zealand's isolated position in the Southwest Pacific and the quality of its marine and terrestrial sedimentary record make it a valuable source of information for studies of global climate change. A section at Bryce Burn in Southland, South Island, provides a record of middle Miocene global cooling associated with buildup of an extensive semi‐permanent ice sheet on Antarctica. The section yielded δ18O, δ13C, lithological, clay mineral, foraminiferal, and pollen data that have been linked to a high‐resolution age model based on magnetostratigraphy and foraminiferal dating. The sequence exhibits evidence for a δ18O c. 0.6‰ positive baseline shift consistent with the age and magnitude of the E3/ Mi3 isotope excursion around 13.9 Ma, carbon maxima 4–6 δ13C excursions, probable orbitally controlled changes in clay mineralogy, and short‐term changes in terrestrial vegetation. This is the first time these stable isotopic events have been recognised in outcrop sequences in New Zealand. There appears ...

article i nfo Multi-scale gravitational instabilities are widespread in the Coastal Ranges of the North Island of New Zealand. We document here a detailed analysis of the Waitawhiti landslide complex, located in the core of the Tawhero syncline, and investigate the potential landslides triggering factors in the area. Four contiguous large slides form the Waitawhiti complex. These slides involve fine-grained Miocene sandstones and massive fractured siltstones. Sliding occurs mostly along nearly horizontal strata. All slides are bounded laterally and/ or distally by deep-incised valleys. Three gas seeps evidencing thermogenic gas release have been discovered in the vicinity of the slides. We propose that river incision, continuously removing distal buttresses, is the main destabilizing factor in the area. However, additional factors, such as tectonic activity and intense rainfall, cannot be excluded. We also propose that fluid overpressure, reducing the effective shear strength at the base of low-permeability layers, may have influenced the triggering of landslides in the Waitawhiti area.

Rares sont les experiences multiculturelles en ligne, en groupes multi-institutionnels et multilingues, qui permettent d’aboutir a l’observation d’attitudes de prise de risque ou d’engagement chez les participants, postures qui pour nous revelent l’authenticite et l’existence de l’acte de rencontrer l’autre. En 2005, nous avons concu une formation en ligne mettant en scene des echanges exolingues en groupe, en partant de l’hypothese que cette rencontre de l’autre sera facilitee, d’une part en regroupant les apprenants en tridem – chacun venant d’une des institutions partenaires de cette formation – et, d’autre part, en combinant deux espaces de communication (blogue et plate-forme audio-synchrone). A partir des donnees recueillies lors de cette experience, nous reconstruisons la genese et la vie des tridems. Nous identifions des criteres qualitatifs permettant de deceler une reelle vie en ligne, en particulier le developpement de fils de discours reliant ecrit et oral, l’occurrence d’incidents critiques. Nous associons certains de ces elements de vie a la manifestation de signes de competences interculturelles du type de celles apparaissant dans le modele de Byram.

High sedimentation rates in Pleistocene active margin basins can provide a very detailed record of tectonic and climatic controls on sediment preservation. A 500 m thick, Pleistocene rock section exposed in northeastern North Island of New Zealand (Kidnappers Group), provides the opportunity to discuss these controls. The section is composed of conglomerate, sandstones, siltstones and minor shales, interbedded with tephra layers. The sediments were deposited in alluvial to shallow marine environments and preserved in stacks of depositional units decimetres to hundreds of metres thick as a result of base-level changes through time. The correlation of base-level changes in the section with the deep sea oxygen isotope stratigraphy shows that the sequences at 10 m and 80 m scales can correlate, respectively, to the 20 and 100 kyr changes in eustatic sea-level, but that the 80-m-thick sequences correlate also to changes in tectonic uplift rates. A major change in the stratigraphical architecture occurs at the Mid-Pleistocene Transition (MPT) when the 40 kyr ice volume variations shifted to a dominant 100 kyr variation. This change includes an increase in the amplitude of the shifts in depositional environments and an overall simplification of the stacking pattern of the depositional units through the MPT. This study illustrates that active margin basins can record orbitally forced sedimentary cycles and points to a possible leading influence of eustasy on the pattern of sediment preservation in tectonically active areas. Copyright © 2004 John Wiley & Sons, Ltd.

International audience; Miocene marine volcaniclastic deposits occur in Mahia Peninsula (North Island, New Zealand) and were sedimented in a forearc setting related to the Hikurangi trench subduction system. These deposits are interbedded with hemipelagic marls, and correspond to simple or amalgamated centimetric- to metric-thick turbiditic sequences. Volcaniclastic material is mainly composed of vitric particles, with crystals (quartz, plagioclase with minor biotite, amphibole, pyroxene and oxides), which are well represented in the coarse-grained fraction. The glass shards are mainly rhyolitic in composition. Three types of volcaniclastic turbidites were distinguished with geochemical data, because distinction is impossible on sedimentary characteristics. (1) Primary monomagmatic turbidites contain both magmatic (bubble wall pumice and shards) and phreatomagmatic (blocky shards with few vesicles and hydroclastically fragmented pyroclasts) vitric particles. The chemical compositions of the vitric particles and the crystals are very homogeneous suggesting a cogenetic origin. These turbidites directly result from unique eruptive events and are probably related to the entrance of hot subaerial pyroclastic flows into the sea, which also led to their transformation into subaqueous gravity flows. (2) Secondary monomagmatic turbidites never contain phreatomagmatic pyroclasts and the glass compositions display a trend from andesites to rhyolites. There is a strong linear correlation in the compositions that suggest that the glass particles are derived from the same magma. Crystals also show a compositional homogeneity. These deposits reflect the succession of several eruptions related to a unique magmatic system and result of the reworking of volcaniclastic material after relatively short storage on the shelf. (3) Secondary multimagmatic turbidites do not display compositional homogeneity of their vitric and mineral components. This implies that the volcaniclastic material has been stored during a relative long period on the shelf before remobilization, and that this sedimentation records the volcanic activity of multiple magmatic sources. Consequently, it has been possible to distinguish primary volcaniclastic turbidites that are directly related to the volcanic activity, from secondary turbidites that result from reworking of previously deposited material on the shelf. Monomagmatic turbidites can be used as stratigraphic and magmatic markers whereas multimagmatic cannot. Multimagmatic turbidites, however, record the evolution of the volcanic arc during longer periods. This leads to the conclusion that the Mahia Peninsula volcaniclastic turbidites distally record the evolution of the source volcanic arc.

This special issue offers a selection of papers presented at the 1999 annual EUROCALL conference, held last September in Besançon, France. Although CALL has a deep rooted tradition in France, EUROCALL’99 was the first large scale international CALL conference to take place in this country. Initiated by the European Association for Computer Assisted Language Learning and the French speaking CALL journal ALSIC (2000), the conference attracted more than 370 full participants coming from 30 countries.

This paper deals with the automatic generation of lexical activities within a computer assisted language learning environment of French as a second language : the ALEXIA system. We intend to show more precisely how the lexical resources which are fully integrated into the system and their use by tools originating from the natural language processing field allow us to generate new computational activities which are both relevant and learner centered. These lexical resources are of paramount importance to facilitate the autonomous learning process. The system however should not be limited to its resources. It should be based also on sound and well defined pedagogical principles which greatly influence its design., Cet article traite de la génération automatique d’activités lexicales au sein d’un environnement informatique d’aide à l’apprentissage lexical du français langue seconde : le système ALEXIA. Plus précisément, nous établissons en quoi les ressources lexicales intégrées au système et leur utilisation par des outils issus du traitement automatique du langage naturel conduisent à générer des activités informatisées d’un type nouveau, pertinentes et adaptées au travail déjà accompli par l’apprenant. Les ressources lexicales s’avèrent indispensables pour favoriser l’apprentissage en autonomie. Cependant, le système ne doit pas se résumer à ses ressources, mais doit s’appuyer sur des principes pédagogiques bien définis qui influent grandement sur sa conception., Selva Thierry, Chanier Thierry. Génération automatique d’activités lexicales. / Automatic Generation of lexical activities in the Alexia system. In: Sciences et techniques éducatives, volume 7 n°2, 2000. pp. 385-411.

Summary Introduction The most frequent neurological expression of Lyme disease (borreliosis) during its secondary phase is meningoradiculitis, but atypical presentations occur. Lyme disease must be considered especially in endemic areas and during the summer (May-October). Cases We report cases of two patients with unusual clinical presentations of neuroborreliosis. Both had acute inflammatory back pain, resistant to the usual analgesic treatment. Both patients responded negatively to questions about tick bites and erythema migrans. Laboratory tests revealed an inflammatory process in only one patient. Lyme disease was confirmed by lymphocytic meningitis and serological tests positive for Borrelia in blood (both cases) and cerebrospinal fluid (one case). Antibiotic treatment led to the disappearance of pain and the normalization of laboratory tests. Discussion Inflammatory back pain, even without radiculitis, may be related to Lyme disease in endemic areas.

Cognition-based arguments in support of using multimedia aids for the learning of vocabulary have so far offered only an imprecise, general framework. CALL experimentalists have also tried to establish the effectiveness of multimedia for vocabulary learning, but their attempts reveal that the underlying representations have not been clearly defined. After reviewing these points, we propose criteria for evaluating the quality of a visual representation in a lexical environment. These criteria are then used to discuss visual representations in paper and electronic dictionaries and in CALL environments. A kind of confusion has been made between multimedia and nonverbal knowledge. Hence visual representations are scarce and limited to concrete words. One way to extend multimedia in lexical learning is to rely on linguistic knowledge and build lexical networks. We present the ALEXIA system, a lexical learning environment for French as a second/foreign language. We detail its network module which can automatically build graphs of some lexical semantic relations. It is a first step for offering learners representations they can easily interpret. Visual representations which can cover a significant part of the lexicon are computable, extendable and interactive.

Resume L'etude du remplissage sedimentaire du domaine avant-arc de 1a marge active de Nouvelle-Zelandea permis de mettre en evidence une discontinuite majeure a la transition mio-pliocene entre environ 6 et 4 Ma. Cette discontinuite separe deux grandes periodes d'evolution de la marge au cours du Neogene : la periode miocene (environ 18-6 Ma), caracterisee par un domaine en subsidence. largement ouvert sur l'ocean; et la periode plio-quaternaire (environ 4-0 Ma) durant laquelle se developpe un veritable bassin avant-arc compris entre l'arc frontal et 1e prisme d'accretion.

We provide ab initio characterization of the negatively charged substitutional nickel (Ni${}_{s}^{\ensuremath{-}}$) impurity in diamond using a hybrid density functional calculation. Ni${}_{s}^{\ensuremath{-}}$ is shown to carry a spin $S=3/2$. The calculated hyperfine couplings on this defect support the identification of the W8 electron paramagnetic resonance center with Ni${}_{s}^{\ensuremath{-}}$ defect. We unambiguously determine the position of the Ni${}_{s}^{\ensuremath{-}}$ acceptor level in the gap. This level is located at about 2.0 eV above the valence band maximum and corresponds to a totally occupied triplet state responsible for the magnetization. We calculated the excited state properties of the defect. Our results may resolve the controversial assignments of Ni${}_{s}^{\ensuremath{-}}$ to different optical centers.

This paper describes "A la Recherche d'un Emploi", ("Job Hunting") a hypermedia courseware teaching French for Specific Purposes and developed as part of the European CAMILLE project. "A la Recherche d'un Emploi" constitutes an early example of a task-based and problem-solving oriented software, which interweaves both linguistic and professional goals, on the one hand, and both theoretical knowledge and a hands-on approach, on the other. The paper looks firstly at the common features of the common features of the communicative and LSP approaches in Second Language Acquisition, and at the relevance of the use of hypermedia in the development of learning environments, from a theoretical standpoint. During the presentation of the courseware, our discussion has given rise to several general issues concerned with this type of software and with the more widely used large-scale hypermedia CALL software. These issues included: the relationships between linguistic contents and domain task, simulation activities, authenticity of material , linguistic and cultural resources, follow-up procedures of the learner's performances, etc. The courseware being presented, our attention was then directed to the manner in which the curriculum perspective should be integrated within the development of the CALL environment. Our methodology is explained throughout, from the planning phase and the learner's needs, through to an evaluation of the phase at its termination.

Analysis of offshore seismic lines suggests that a strong relationship exists between tectonic structures and fluid migration in accretionary prisms. However, only few field analogues of plumbing systems and their tectonic frameworks have been investigated in detail until now. The uplifted accretionary prism of the Hikurangi Margin (North Island, New Zealand) exposes early to late Miocene mudrocks in coastal cliffs of Cape Turnagain and in the Akitio syncline, south-east of the Pongaroa city. These outcrops display tubular carbonate concretions corresponding to complex subsurface plumbing networks of paleo-seeps within Miocene trench slope basins. We present here, new results on the spatial distribution of these tubular carbonate concretions, with particular attention to their relation to tectonic structures. In the Pongaroa area, tubular carbonate concretions in lower Miocene mudrocks occur along a N-S trend, while in middle Miocene strata they occur along a NNE-SSW direction. The N-S trend parallels a major fault zone (i.e.the Breakdown fault zone), which separates two wide synclines, the Waihoki and the Akitio synclines. During the Early-Middle Miocene, the Breakdown fault zone controlled the evolution of the Akitio trench slope basin constituting its western edge. The NNE-SSW strike parallels the axis of the Akitio syncline and is also parallel to the present-day subduction front. Our results therefore show that tubular concretions are parallel to post-Middle Miocene second order folding and thrusting in the northeastern limb of the Akitio syncline. In the Cape Turnagain area, tubular concretions occur in the western limb of the Cape Turnagain syncline, in the footwall of the major seaward-verging Cape Turnagain fault. This suggests that fluid migrations may occur not only in the crests of anticlines, as observed offshore for present-day plumbing system of cold seeps, but also in the footwalls of thrust faults. All these observations show that the spatial distribution of tubular concretions is controlled by regional tectonic structures with paleo-fluid migrations related to major deformation episodes of the accretionary prism. Thus, we distinguish three episodes events that likely triggered fluid migration leading to the formation of the tubular concretions: (1) In the Early Miocene, shortly after the onset of development of the Akitio trench slope basin, on its inner (western) edge; (2) During the late Middle Miocene, during an extensional deformation episode on the western limb of the Akitio trench slope basin; (3) At the end of the Late Miocene, during a second major shortening period at the footwall of major thrust fault, such as in the Cape Turnagain area.

The synthetic (virtual) world Second Life can be defined as a social networking environment for it allows users to network informally by initiating relationships with other users, often strangers with whom they share no previous offline connection. Users can also connect with other users with whom they have previously established offline relationships. In the synthetic world, networking can occur by interacting, and later friending, other users whose avatars are proxemically close to a user inworld. This is facilitated by the feature of the synthetic world which allows any interaction between users in the public audio or textchat channels to be heard / read by other nearby users. Users can also initiate relationships through similar interest groups and choose to create a public profile, albeit relating this profile to that of their avatar or their physical world (first world) identity. Users who friend each other can view the newsfeed and interest groups as well as the list of connections of one another, and can navigate the latter. The development of social networking environments allows users to construct online personae / identities which may differ from their first world identities (Turkle, 2011). The environments offer new ways of communicating both verbally and nonverbally which imply new ways of being, of showing and negotiating identities (Nagy, 2010). As fully anonymous social networking environments, synthetic worlds offer specific possibilities for identity construction and new ways of interacting because users are represented in the environment by an avatar through which they communicate. In the language-learning (L2) domain, interest is emerging in this type of environment. Research suggests that synthetic worlds may reduce student apprehension concerning interacting in a second language (Schweinhorst, 2002) and increase the students' sense of presence and community (Nowak and Biocca, 2004). However, the questions of whether and how language learners use avatars to develop an identity, the impact of avatar use on participation and interaction in a L2 remain largely unexplored. In this chapter, we explore the above questions through the data analysis from an experiment designed around a course in Second Life which formed part of the European project ARCHI21 . For this course, a Content and Language Integrated Learning (CLIL) approach was chosen for students of Architecture whose foreign languages (L2) were French (FFL) or English (EFL). We explore how these students developed their online identities and how these identities were forged through avatar appearance and the use of nonverbal acts, including gestures. We examine how these identities impacted interaction. Firstly, how changing avatar appearance influenced how students addressed each other inworld and their level of verbal participation in L2 interaction. Secondly, whether constructing an identity partially through nonverbal communication acts in this social networking environment may have created opportunities for increased L2 verbal participation. In our study, no instructions were given to the students regarding avatar appearance. The research questions presented here were formulated after remarking upon how students changed their avatar appearance and used nonverbal communication during the course. Our study focuses on the L2 interaction during open-ended activities rather than question-answer exchanges which may be more typical of a non-CLIL learning context.

The Maya were known for their astronomical proficiency. This is demonstrated in the Mayan codices where ritual practices were related to astronomical events/predictions. Whereas Mayan mathematics were based on a vigesimal system, they used a different base when dealing with long periods of time, the Long Count Calendar (LCC), composed of different Long Count Periods: the Tun of 360 days, the Katun of 7200 days and the Baktun of 144000 days. There were two other calendars used in addition to the LCC: a civil year Haab' of 365 days and a religious year Tzolk'in of 260 days. Another cycle was also in use: a 3276-day cycle (combination of the 819-day Kawil cycle and the 4 directions-colors). Based on the hypothesis that Mayan astronomers had a good knowledge of naked-eye astronomy, we propose here an explanation of the origin of the LCC, the Haab', the Tzolk'in and the 3276-day cycle. This study sheds more light on the connection between arithmetic, astronomy and religion in Maya civilization.

In the last few years, the community working on Computer Assisted Learning has started considering a different type of learning as an alternative to traditional ones: collaborative learning (or cooperative learning). We address the question of defining how collaboration could be beneficial to a computer environment for language learning. In order to answer that question, we refer to various research fields, such as Applied linguistics, Psychology of Education, Artificial Intelligence and Education. From thereon we propose an application of collaborative learning to one particular domain of the second language: interrogative sentences in French.

The electronic and magnetic properties of neutral substitutional transition-metal dopants in diamond are calculated within density-functional theory using the generalized gradient approximation to the exchange-correlation potential. Ti and Fe are nonmagnetic, whereas the ground states of V, Cr, and Mn are magnetic with a spin entirely localized on the magnetic ion. For Co, Ni, and Cu, the ground state is magnetic with the spin distributed over the transition-metal ion and the nearest-neighbor carbon atoms; furthermore a bound state is found in the gap that originates from the hybridization of the $3d$-derived level of the dopant and the $2p$-derived dangling bonds of the nearest-neighbor carbons. A $p$-$d$ hybridization model is developed in order to describe the origin of the magnetic interaction. This model predicts high-spin to low-spin transitions for Ni and Cu under compressive strain.