LEBRUN , Jean-Frederic

This special issue includes papers covering various topics of importance in the Caribbean such as geodynamics, environmental evolutions and natural hazards (fig. 1). This collection of articles focuses in particular on geodynamic processes occurring along the Caribbean plate boundaries, on volcanic hazards and on flooding. Given the recently...

With hull-mounted multibeam echosounder data, wereport for the first time along the active Ecuadorian margin,acoustic signatures of water column fluid emissions and seep-relatedstructures on the seafloor. In total 17 flare-shaped acousticanomalies were detected from the upper slope (1250 m) to the shelfbreak (140 m). Nearly half of the...

The initial sediment lithification reactions start with complex interactions involving all components of the sedimentary material (minerals, surface water, decomposing organic matter and living organisms). This is the eogenesis domain (0 to 2000 m below seafloor), covering a burial interval ranging from the interface with the biosphere down to...

Selected high-resolution seismic-reflection profiles and multibeam bathymetry acquired along the convergent Ecuador margin during the ATACAMES cruise on onboard the R/V L'Atalante (Jan.15–Feb.18, 2012) allow a preliminary evaluation of the neotectonic development and stratigraphic evolution of the margin based on the sismo-stratigraphic...

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The influence of the highly oblique plate convergence at the northern Lesser Antilles onto the margin strain partitioning and deformation pattern, although frequently invoked, has never been clearly imaged. The Anegada Passage is a set of basins and deep valleys, regularly related to the southern boundary of the Puerto Rico-Virgin Islands...

We present the results from a new grid of deep penetration multichannel seismic (MCS) profiles over the 280-km-long north-central segment of the Lesser Antilles subduction zone. The 14 dip-lines and 7 strike-lines image the topographical variations of (i) the subduction interplate décollement, (ii) the top of the arcward subducting Atlantic...

Since Cretaceous, the Lesser Antilles subduction zone has undergone a multiphase tectonic history resulting in its present-day complex architecture. One peculiar aspect for this subduction is the trench / arc convexity from Martinique, in the South, where the subduction is frontal, to Anguilla, to the North, where the convergence obliquity is...

Forearc sedimentary basins record changes in tectonic regime and are thus key area to investigate the tectonic history of a subduction zone through time.Since Cretaceous, The Lesser Antilles subduction zone has undergone a multiphase tectonic history resulting in its present-day complex architecture. One peculiar aspect for this subduction is...

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In the frame of the GAARAnti ANR-17-CE31-0009 project, we aim at establishing the paleogeography of the arc/forearc areas of the Northern Lesser Antilles over the last 35 Ma to bring constraints for the mammal fauna dispersion paleo-biogeographic models from south America to Greater Antilles. Available paleogeographic maps are ancient (Stephan...

Upper plates in subduction zones are prone to record slab dynamics as their strain pattern, uplift-subsidence records and volcanic arc activity accommodates variations of slab parameters in terms of dip, density and rheology. The ANR GAARAnti aims at tracking the timing of land emersions and submersions along the Lesser Antilles subduction...

Along the convex Northern Lesser Antilles margin, plate convergence obliquity increases northward resulting in subduction normal to the trench to the west of Guadeloupe and highly oblique (>75°) to the North of Virgin Island. In this context, tectonic structures related to strain partitioning has long been debated, but are still poorly imaged....

Strain partitioning related to oblique plate convergence has long been debated in Northern Lesser Antilles. Geophysical data acquired during the ANTITHESIS cruises highlight that the sinistral strike‐slip Bunce Fault develops along the vertical, long, and linear discontinuity between the sedimentary wedge and a more rigid backstop. The...

Located in the southeastern Caribbean, the Grenada Basin is bounded to the east by the modern Lesser Antillesisland arc, to the west by the Aves Ridge, commonly interpreted as a Cretaceous-Paleocene extinct volcanic arc,and to the south by the transpressive plate boundary with South America. The Grenada Basin has long ...

The purpose of the GAARAnti project is to unravel couplings between deep Earth dynamics and evolutionary processes through an innovative and original multi-disciplinary study combining Earth and Life sciences. This innovative approach will reconcile biological and geological clocks and timeframes through the combined use of radiochronological...

Worldwide, forearc trench-perpendicular basins are interpreted as the result of trench-parallel extension possibly due to either strain partitioning as at the Aleutians (Ryan & Scholl, 1989) and Ryukyu (Nakamura, 2004) Subduction Zones, and/or to increasing margin curvature as at the Marianas (Heeszel et al., 2008) and Hellenic trenches...

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This work focuses on the analysis of a unique set of seismological data recorded by two temporary networks of seismometers deployed onshore and offshore in the Central Lesser Antilles Island Arc from Martinique to Guadeloupe islands. During the whole recording period, extending from January to the end of August 2007, more than 1300 local...

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In this paper we present and discuss new investigations performed on both the magmatic basement and the sedimentary formations of La Désirade. We report structural and sedimentary evidences for several episodes of deformation and displacement occurring prior to the present day tectonics. The main faults, respectively N130 ± 10°, N040 ± 10° and...

An integrated stratigraphic study was conducted on the shallow water carbonate platforms of the Guadeloupe archipelago to refine the tectonic evolution of the Lesser Antilles forearc. The carbonate platforms are now dated to the Zanclean-Calabrian interval, and their demise occurred between 1.5 and 1.07 Ma. The precise chronostratigraphy allows...