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Present‐day convergence between Caribbean and North American plates is accommodated by subduction zones, major active thrusts and strike‐slip faults, which are probably the source of the historical large earthquakes on Hispaniola. However, little is known of their geometric and kinematic characteristics, slip rates and seismic activity over time. This information is important to understand the active tectonics in Hispaniola, but it is also crucial to estimate the seismic hazard in the region. Here we show that a relatively constant NE‐directed shortening controlled the geometry and kinematics of main active faults in southern central Hispaniola, as well as the evolution of the Quaternary stress regime. This evolution included a pre‐Early Pleistocene D1 event of NE‐trending compression, which gave rise to the large‐scale fold and thrust structure in the Cordillera Central, Peralta Belt, Sierra Martín García and San Juan‐Azua basin. This was followed by a near pure strike‐slip D2 stress regime, partitioned into the N‐S to NE‐SW transverse Ocoa‐Bonao‐La Guácara and Beata Ridge fault zones, as well as subordinate structures in related sub‐parallel deformation corridors. Shift to D2 strike‐slip deformation was related to indentation of the Beata Ridge in southern Hispaniola from the Early to Middle Pleistocene and continues today. D2 was locally coeval by a more heterogeneous and geographically localized D3 extensional deformation. Defined seismotectonic fault zones divide the region into a set of simplified seismogenic zones as starting point for a seismic hazard modeling. Highest peak ground acceleration values computed in the Ocoa Bay establish a very high seismic hazard. Key Points: Active faults in central southern Hispaniola are controlled by NE‐directed shorteningQuaternary stress regime evolution includes a compressional D1 followed by a strike‐slip D2, locally coeval with an extensional D3Modeling establishes a very high seismic hazard zone centered in the Ocoa Bay [ABSTRACT FROM AUTHOR]

New detrital zircon petrochronological data (~380 analysed grains), including U-Pb dating, trace element, and isotopic analyses from modern sediments and Oligocene-Miocene strata, cropping out along the western slope of the Baudó Range in the northern Pacific coast of Colombia (Tribugá and Cupica Gulfs), are used to assess the nature of Cretaceous basement rocks. Modern sediments of the Cupica Gulf show the existence of ~100-84 Ma zircons with juvenile isotopic signatures (εHf shifting from +11.0 to +12.9), and subduction-related geochemical features, as indicated by the low content of REE (<4000 ppm), Nb (<14 ppm) and Ti (<6 ppm), and the common presence of positive Ce and Eu anomalies. The detrital ages distribution of the analysed sample from the Cupica Gulf, when compared with new and available detrital zircon U-Pb data (~3500 individual ages) from Cretaceous to Pliocene strata of surrounding regions, is very dissimilar, making it difficult for them to be recycled from older sediments. Instead, we interpret the ~100-84 Ma zircons as derived from arc-related igneous rocks probably exposed along unexplored regions of the axis of the northern Baudó Range, which could be associated with the early growth of the Central American arc. Our new data encourage studying barely explored regions of northwestern South America to test available hypotheses regarding the origin of Cretaceous circum-Caribbean island arcs and its linkages with the tectonics of northwestern South America. [ABSTRACT FROM AUTHOR]

Abstract Present‐day convergence between Caribbean and North American plates is accommodated by subduction zones, major active thrusts and strike‐slip faults, which are probably the source of the historical large earthquakes on Hispaniola. However, little is known of their geometric and kinematic characteristics, slip rates and seismic activity over time. This information is important to understand the active tectonics in Hispaniola, but it is also crucial to estimate the seismic hazard in the region. Here we show that a relatively constant NE‐directed shortening controlled the geometry and kinematics of main active faults in southern central Hispaniola, as well as the evolution of the Quaternary stress regime. This evolution included a pre‐Early Pleistocene D1 event of NE‐trending compression, which gave rise to the large‐scale fold and thrust structure in the Cordillera Central, Peralta Belt, Sierra Martín García and San Juan‐Azua basin. This was followed by a near pure strike‐slip D2 stress regime, partitioned into the N‐S to NE‐SW transverse Ocoa‐Bonao‐La Guácara and Beata Ridge fault zones, as well as subordinate structures in related sub‐parallel deformation corridors. Shift to D2 strike‐slip deformation was related to indentation of the Beata Ridge in southern Hispaniola from the Early to Middle Pleistocene and continues today. D2 was locally coeval by a more heterogeneous and geographically localized D3 extensional deformation. Defined seismotectonic fault zones divide the region into a set of simplified seismogenic zones as starting point for a seismic hazard modeling. Highest peak ground acceleration values computed in the Ocoa Bay establish a very high seismic hazard.

Relative Caribbean‐North American plate motion is partitioned over the trench and intra‐Caribbean plate faults that bound large scale tectonic blocks. Quantifying the kinematic evolution of this tectonic corridor is challenging because much of the region is submarine. We present an extensive regional paleomagnetic data set (1,330 cores from 136 sampling locations) from Eocene and younger rocks of the northern Lesser Antilles, the Virgin Islands, and Puerto Rico, and use a statistical bootstrapping approach to quantify vertical axis block rotations. Our results show that the Puerto Rico–Virgin Island (PRVI) block and the Northern Lesser Antilles (NoLA) block formed two coherently rotating domains that both underwent at least 45° counterclockwise rotation since the Eocene. The first ∼20° occurred in tandem in late Eocene and Oligocene time, after which the blocks were separated in the Miocene by the opening of the Anegada Passage. The last 25° of rotation of the PRVI block ended in the middle Miocene, whereas the NoLA block rotated slower, until the latest Miocene. The boundary between the NoLA block and a non‐rotated Southern Lesser Antilles was likely the Monserrat‐Harvers fault zone. These results require hundreds of kilometers of intra‐Caribbean motions with oroclinal bending of the trench or forearc sliver motion along the curved plate boundary as endmembers. These data invite a critical re‐evaluation of the kinematic reconstruction of Caribbean‐North American plate motion. The consequent changes in paleogeography may provide a new view on the enigmatic eastern Caribbean paleo‐biogeography and the Paleogene dispersal of South American mammals toward the Greater Antilles. Key Points: Since the late Eocene the Puerto Rico‐Northern Lesser Antilles block underwent ≃45° of counterclockwise rotationDuring the Miocene the opening of the Anegada Passage split this block in two and accommodated part of their differential rotation rateOur results imply intraplate motion of a forearc sliver over 500 km with profound effects on Paleogene Caribbean paleogeography [ABSTRACT FROM AUTHOR]

The Lesser Antilles subduction zone marks the convergence between the Caribbean Plate and the oceanic Atlantic part of the America Plate. A specificity of this subduction is the development of a huge accretionary prism, the Barbados complex. As other subduction zones, the Lesser Antilles one has the potential to produce megathrust-associated earthquakes and related tsunamis. This study evaluates the potential hazard of tsunami scenarios along this eastern boundary of the Caribbean Plate, taking into account its specificities. We define six scenarios along the Lesser Antilles subduction zone including three M w 7.5 , 8.0 and 8.5 earthquake models, in both northern and southern parts of the arc. We incorporate in tsunami simulations the effect of sediment amplification in tsunami generation. In the southern half, the thick sediments pile, related to tectonic accretion, appears much more effective than the much thinner accumulation characterizing the northern half. The bed shear stress is also computed in this study as it is an important factor in sediment transport which can show the potential locations for sediment movement by tsunamis. Our results indicate the ability of scenario earthquakes to produce powerful tsunamis. The impacts of northern scenarios on Guadeloupe could be severe (maximum tsunami wave height of > 5 m ), whereas the impacts from southern scenarios are relatively less strong (maximum wave amplitude of < 5 m ). The tsunami waves produced by M w 8.0 and 8.5 appear able to inundate the coast of Sainte-Anne, Guadeloupe, up to 2 km . The distributions of bed shear stress from northern scenarios suggest that the offshore Leeward Islands could be potentially prone to sediment transport as possible tsunami deposits have been found in the region in former geological studies. [ABSTRACT FROM AUTHOR]

A catastrophic earthquake (magnitude Mw 7.2) occurred on 14 August 2021 in Haiti. Sea surface temperature (SST) and sea potential temperature (SPT) observed from satellites show pronounced changes prior to the main earthquake event. The changes are observed near the epicenter and the boundary of the Caribbean Plate. Here we have carried out a detailed analysis of ocean, atmosphere and land surface parameters (sea water salinity, chlorophyll-a, latent energy flux, sensible heat flux, specific humidity, air temperature, methane and land surface temperature) using multiple satellite data to understand the possible mechanism of sea temperature changes. The strong coupling among these geophysical and geochemical parameters has been found within 2-week prior to the 2021 Haiti Mw 7.2 earthquake due to the interaction between ocean/land and atmosphere during the last phase of earthquake preparation period caused by the tectonic movement. The spatiotemporal distribution pattern of anomalies is discussed in view of the focal mechanism of the earthquake event.

According to GPS measurements, the Caribbean plate is moving east‐northeastward relative to the North American plate at a rate of ∼20 mm/a. This oblique motion is partly accommodated in southern Hispaniola by northward underthrusting/subduction bellow the Muertos submerged accretionary prism and the Peralta fold‐and‐thrust belt. This work investigates the active transition zone that connects Muertos and Peralta: the Ocoa‐Bonao‐La Guacara fault zone (OBFZ). Combined detailed structural analysis at macroscopic and mesoscopic scales, regional magnetic data and seismicity analysis, geomorphic observations, fault‐slip data inversion and geochronology of Quaternary deposits allow to establish the deformation pattern for the OBFZ along southern central Hispaniola. Distinct tectonic regimes have occurred successively in the Neogene, within a consistent regional NE‐trending horizontal shortening: (a) a lower Miocene to Early Pleistocene D1 regime characterized by SW‐directed thrusting that homogeneously affects the region; and (b) an Early/Middle Pleistocene to Holocene D2 regime of strike‐slip to transpressional faulting mainly located along the OBFZ. The change is coeval with the tectonic indentation of the Beata Ridge in the back‐arc region of the Hispaniola microplate. Finally, a Late Pleistocene to Holocene D3 extensional regime has a local development around the Ocoa Bay. Part of the present‐day stress‐field induced by the Beata Ridge collision is accommodated by the OBFZ within the Hispaniola microplate. This fault zone defines the onland transition between oceanic subduction and arc‐oceanic plateau collision. Due to its length and potential to generate large earthquakes, the OBFZ must be considered in the regional seismic hazard assessment. Key Points: The Ocoa‐Bonao‐La Guacara fault zone (OBFZ) is composed of four segments with specific kinematicsThe OBFZ records an Early to Middle Pleistocene to Holocene regime of strike‐slip to transpressional faultingThe OBFZ defines the active transition between oceanic subduction and arc‐oceanic plateau collision [ABSTRACT FROM AUTHOR]

The Caribbean plate is an enclosed oceanic basin whose formation and evolution are controversial. In the most commonly accepted model, the Caribbean plate is mainly composed of the Caribbean Large Igneous Province (CLIP) and the buoyant characteristic of this oceanic plateau resisted subduction and allowed an eastward migration to its present position north of South America. In this study, we integrate a broad range of geophysical and geomorphological data to define structural elements and present‐day tectonics of the Caribbean plate and the surrounding region. We present a Bouguer gravity anomaly map and a new crustal thickness map that documents large areas of normal‐thickness oceanic crust within the Venezuela and Colombia basins of the Caribbean plate. Selected cross sections of seismicity and P‐wave anomalies from a seismic tomographic model depict the present‐day geometry of subducting oceanic plates within the Caribbean region. We observe that rather than resisting subduction, as expected for the thick crust of a buoyant large igneous province, the subduction of the Caribbean plate can be traced to a depth of 600 km beneath NW South America. This, together with the crustal thickness map, implies that a significant area of the Caribbean plate, including the subducted portion, is composed of normal‐thickness oceanic crust. As proposed by the Pacific origin model, the Caribbean plate likely migrated eastward from the Pacific Ocean as an oceanic plate mostly with normal‐thickness crust and limited portions of the crust thickened by hot spot volcanism (CLIP). Plain Language Summary: The Caribbean plate and northern South America are studied using topography and multiple geophysical data sets, including gravity, magnetics, crustal thickness, seismicity, and seismic images of the upper mantle. These data sets were used to analyze crustal properties as well as the past and present interaction of tectonic plates in this region. Our results show large areas of ocean crust with normal thickness within the Caribbean plate. Seismicity in the circum‐Caribbean subduction zones rarely exceeds 200 km in depth, whereas seismic imaging shows subducting slabs reach a depth of 600 km or more. This implies that subduction has been long‐lived at these active margins. These results also show that the Caribbean plate is subducting beneath NW South America, something that would not be expected for the thick crust of a buoyant large igneous province. As proposed by the Pacific origin model, the Caribbean plate migrated eastward from the Pacific Ocean as an oceanic plate mostly with normal‐thickness crust and limited portions of the crust thickened by hot spot volcanism. Key Points: A new crustal thickness map and gravity maps reveal large areas of normal‐thickness oceanic crust within the Caribbean plateP‐wave seismic tomography images show that the subducted Caribbean plate reaches 660 km depth, but slab seismicity terminates at 200 kmCombined seismicity, gravity, and magnetic maps reveal the active tectonics of the circum‐Caribbean accretionary and magmatic boundary [ABSTRACT FROM AUTHOR]

Abstract The Caribbean plate is an enclosed oceanic basin whose formation and evolution are controversial. In the most commonly accepted model, the Caribbean plate is mainly composed of the Caribbean Large Igneous Province (CLIP) and the buoyant characteristic of this oceanic plateau resisted subduction and allowed an eastward migration to its present position north of South America. In this study, we integrate a broad range of geophysical and geomorphological data to define structural elements and present‐day tectonics of the Caribbean plate and the surrounding region. We present a Bouguer gravity anomaly map and a new crustal thickness map that documents large areas of normal‐thickness oceanic crust within the Venezuela and Colombia basins of the Caribbean plate. Selected cross sections of seismicity and P‐wave anomalies from a seismic tomographic model depict the present‐day geometry of subducting oceanic plates within the Caribbean region. We observe that rather than resisting subduction, as expected for the thick crust of a buoyant large igneous province, the subduction of the Caribbean plate can be traced to a depth of 600 km beneath NW South America. This, together with the crustal thickness map, implies that a significant area of the Caribbean plate, including the subducted portion, is composed of normal‐thickness oceanic crust. As proposed by the Pacific origin model, the Caribbean plate likely migrated eastward from the Pacific Ocean as an oceanic plate mostly with normal‐thickness crust and limited portions of the crust thickened by hot spot volcanism (CLIP).

Located in northern Dominican Republic, the Early Cretaceous Rio Boba mafic‐ultramafic plutonic sequence constitutes a lower crust section of the Caribbean island arc, made up by gabbroic rocks and subordinate pyroxenite. Modal compositions, mineral chemistry, whole‐rock compositions and thermobarometric calculations indicate that pyroxenites and gabbronorites represent a cumulate sequence formed by fractionation of tholeiitic magmas with initially very low H2O content in the lower crust of the arc (0.6–0.8 GPa). Melts evolved along a simplified crystallization sequence of olivine → pyroxenes → plagioclase → Fe‐Ti oxides. The magmatic evolution of the Rio Boba sequence and associated supra‐crustal Puerca Gorda metavolcanic rocks is multi‐stage and involves the generation of magmas from melting of different sources in a supra‐subduction zone setting. The first stage included the formation of a highly depleted substrate as result of decompressional melting of a refractory mantle source, represented by a cumulate sequence of LREE‐depleted island arc tholeiitic (IAT) and boninitic gabbronorites and pyroxenites. The second stage involved volumetrically subordinate cumulate troctolites and gabbros, which are not penetratively deformed. The mantle source was refractory and enriched by a LILE‐rich hydrous fluid derived from a subducting slab and/or overlying sediments, and possibly by a LREE‐rich melt. The third stage is recorded in the upper crust of the arc by the Puerca Gorda "normal" IAT protoliths, which are derived from an N‐MORB mantle source enriched with a strong subduction component. This magmatic evolution has implications for unraveling the processes responsible for subduction initiation and subsequent building of the Caribbean island arc. Plain Language Summary: The process of intra‐oceanic subduction brings an oceanic slab under an overriding oceanic slab resulting in the formation of a convergent plate margin. Consequently, an oceanic island arc is formed in the upper plate, as is the case of the magmatically active arcs of southwest Pacific. Unlike continental magmatic arcs, intra‐oceanic arcs are less studied because a large part of them is located below sea level, emerging as chains of small islands that constitute just the tops of large submarine volcanoes. In the northern Dominican Republic, recent geochemical studies of the Caribbean volcanic and plutonic rocks indicate that older tholeiitic and boninitic melts were successively replaced by younger island arc tholeiitic melts. This change in the compositional magmas, as well as related mantle sources, places important constraints on the magmatic and tectonic processes associated with the initiation and evolution of the Caribbean island arc. In this sense, the results presented in this work allow to be compared with the chemical stratigraphy observed in actual oceanic arcs and with the predictions of models for the initiation of intra‐oceanic subduction, which constitutes one of the main questions not completely resolved of the global plate tectonics. Key Points: The Rio Boba mafic‐ultramafic plutonic sequence is a lower crust section of the Caribbean island arcIt is made up by gabbroic rocks and subordinate lenses of pyroxeniteTheir magmatic evolution record subduction initiation and subsequent arc building [ABSTRACT FROM AUTHOR]

Abstract Located in northern Dominican Republic, the Early Cretaceous Rio Boba mafic‐ultramafic plutonic sequence constitutes a lower crust section of the Caribbean island arc, made up by gabbroic rocks and subordinate pyroxenite. Modal compositions, mineral chemistry, whole‐rock compositions and thermobarometric calculations indicate that pyroxenites and gabbronorites represent a cumulate sequence formed by fractionation of tholeiitic magmas with initially very low H2O content in the lower crust of the arc (0.6–0.8 GPa). Melts evolved along a simplified crystallization sequence of olivine → pyroxenes → plagioclase → Fe‐Ti oxides. The magmatic evolution of the Rio Boba sequence and associated supra‐crustal Puerca Gorda metavolcanic rocks is multi‐stage and involves the generation of magmas from melting of different sources in a supra‐subduction zone setting. The first stage included the formation of a highly depleted substrate as result of decompressional melting of a refractory mantle source, represented by a cumulate sequence of LREE‐depleted island arc tholeiitic (IAT) and boninitic gabbronorites and pyroxenites. The second stage involved volumetrically subordinate cumulate troctolites and gabbros, which are not penetratively deformed. The mantle source was refractory and enriched by a LILE‐rich hydrous fluid derived from a subducting slab and/or overlying sediments, and possibly by a LREE‐rich melt. The third stage is recorded in the upper crust of the arc by the Puerca Gorda “normal” IAT protoliths, which are derived from an N‐MORB mantle source enriched with a strong subduction component. This magmatic evolution has implications for unraveling the processes responsible for subduction initiation and subsequent building of the Caribbean island arc.

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Abstract Subduction zone dynamics are important for a better understanding of natural hazards, plate tectonics, and the evolution of the planet. Despite this, the factors dictating the location and style of volcanism are not well‐known. Here we present Rayleigh Wave imaging of the Lesser Antilles subduction zone using the ocean bottom and land seismic data collected as a part of the VoiLA experiment. This region is an important global endmember that represents a slow (

Subduction zone dynamics are important for a better understanding of natural hazards, plate tectonics, and the evolution of the planet. Despite this, the factors dictating the location and style of volcanism are not well‐known. Here we present Rayleigh Wave imaging of the Lesser Antilles subduction zone using the ocean bottom and land seismic data collected as a part of the VoiLA experiment. This region is an important global endmember that represents a slow (<19 mm/yr) convergence rate of old (80–120 Ma), Atlantic lithosphere formed at a slow spreading ridge. We image the fast slab, the fast‐overriding plate and the slow mantle wedge across the entire arc. We find slow velocity anomalies (∼4.1 km/s) in the mantle wedge directly beneath the arc with local minima beneath Dominica/Martinique, Montserrat and the Grenadines. We observe that slow velocities in the wedge extend 200 km into the back arc west of Martinique. The slowest mantle wedge velocity anomaly is more muted than several global wedges, likely reflecting the lower temperatures and less partial melt predicted for the Antilles. Subducted fracture zones and plate boundaries are a potential source of hydration, since they are located near the anomalies, although not directly beneath them. To match our observations, geodynamic models with a broadly hydrated mantle wedge are required, which can be achieved via deep hydration of the slab, and fluid release further into the back arc. In addition, 3‐D flow and melt migration or ponding are required to explain the shape and location of our anomalies. Key Points: We image a fast slab and upper plate with slow anomalies found in the wedge beneath the central part of the arc and the backarcLow velocity wedge anomalies are associated with projected fracture zones and tectonic plate boundaries on the downgoing slabVelocity anomalies in the wedge indicate excess fluids/melt over broad regions explained by 3‐D flow, melt compaction, or ponding [ABSTRACT FROM AUTHOR]

2D gravimetric and magnetic models were generated from the northwestern region of Venezuela, to determine the crustal structure of the Mérida Andes and to obtain the depth of the main discontinuities, as well as to estimate the depth of the basement, the thickness of the sediments and the geometry of the geological structures present. The crustal models were generated using terrestrial gravity data, satellite gravity data from the EGM2008 (Earth Gravity Map 2008) and satellite magnetic data from the EMAG2 (Earth Magnetic Anomaly Grid 2). The models show a lithosphere structure represented by horizontal and vertical layers and blocks, whose patterns of variation of density and susceptibility were elaborated in function of vertical and lateral variations. An evaluation of the proposed models for the Mérida Andes was carried out, where it was determined that the profiles show a higher degree of correlation with the floating orogen model, which is described in the literature, suggesting a regional compensation system. The flexion of the South American Plate is produced by the orogenic load of the Mérida Andes and the Barinas-Apure Basin, while the flexion of the Maracaibo Block can be attributed to both the large sediment load it carries and the type Asubduction with the South American Plate. In addition, there is a type B-subduction of the Caribbean Plate below the South American Plate in a NW-SE direction with a dip of ~25 °. Likewise, it was observed that the Mohorovicic discontinuity of the South American Plate is deeper than the Maracaibo Block. [ABSTRACT FROM AUTHOR]

Abstract The northern margin of Hispaniola records the oblique collision/underthrusting of the Bahamas Carbonate Province with the island-arc. Due to the collision, northern Hispaniola has suffered several natural disasters caused by major earthquakes and tsunamis, such as the historic earthquake of 1842, the tsunami caused by earthquake-driven slumping in 1918 in the Mona Passage, the seismic crisis of 1943–1953 with five events of M > 7.0 or the seismic crisis of 2003 with a main shock of M6.3 and a large aftershock of M5.3. Using new swath multibeam bathymetry data and vintage single- and multi-channel seismic profiles, we have performed a regional scale analysis and interpretation of the shallow morpho-structure and active processes along the northern margin of the Dominican Republic. We have identified three morphostructural provinces: a) the Bahamas Carbonate Province, b) the Hispaniola Trench and c) the Insular Margin, which are divided into two tectonic domains, the Collision Domain and Underthrusting Domain. The southern slope of the Bahamas Carbonate Province shows a very irregular morphology produced by active erosive processes and normal dip-slip faulting, evidence of an extensional tectonic regime and margin collapse. This collapse is of major extent in the Oblique Collision Domain where there are erosive and fault escarpments with higher dip-slip fault throws. The Hispaniola Trench is formed by the Caicos and Hispaniola basins in the underthrusting domain, and by the Santisima Trinidad and Navidad basins in the Oblique Collision Domain. They have a flat seafloor with a sedimentary filling of variable thickness consisting of horizontal or sub-horizontal turbiditic levels. The turbiditic fill mostly proceeds from the island arc through wide channels and canyons, which transports sediment from the shelf and upper slope. The Insular Margin comprises the Insular Shelf and the Insular Slope. The active processes are generated on the Insular Slope where the Northern Hispaniola Deformed Belt is developed. This Deformed Belt shows a very irregular morphology, with a WNW-ESE trending N verging imbricate thrust-and fold system. This system is the result of the adjustment of the oblique collision/underthrusting between the North American plate and the Caribbean plate. In the Oblique Underthrusting Domain the along-strike development of the imbricate system is highly variable, forming salients and recesses. This variability is due to along-strike changes in the sediment thickness of the Hispaniola Trench, as well as to the variable topography of the underthrusting Bahamas Carbonate Province. In the Oblique Collision Domain, the morphology of the Insular Slope and the development of the Deformed Belt deeply change. The imbricate system is barely inferred and lies upslope. These changes are due to the active collision of Bahamas Carbonate Province with the Insular Margin where the spurs are indented against the Insular Margin. Throughout the entire area studied, gravitational instabilities have been observed, especially on the Insular Margin and to a lesser extent on the southern slope of the Bahamas Carbonate Province. These instabilities are a direct consequence of the active underthrusting/collision process. We have mapped large individual slumps north of Puerto Plata in the Oblique Underthrusting Domain and zones of major slumps in the Oblique Collision Domain. These evidences of active processes must be considered as near-field sources in future studies on the assessment of tsunami hazards in the region. Highlights • Northern Hispaniola Margin is studied with new high-resolution bathymetry and vintage seismic data. • Northern Hispaniola Deformed Belt forms an active N-verging fold-and-thrust imbricate system. • Gravity failures are frequent features in the Northern Hispaniola Margin and Bahamas Banks slope. • Oblique collision accelerates the Bahamas Carbonate Province collapse and retreat. • New observations help the assessment of tsunami hazards in the Northern Caribbean region. [ABSTRACT FROM AUTHOR]

Abstract The northern Andes of Colombia comprise two non-cogenetic Paleogene arcs formed in contrasting geodynamic settings including continental and oceanic domains. New whole-rock geochemistry and isotopic constraints, together with a review of 332 geochemical, 76 isotopic and 204 geochronological data from Paleocene to Eocene volcanic and plutonic rocks exposed in central and western Colombia and Panama, are used to evaluate cause-effect relations between regional plate kinematics and the spatio-temporal distribution of the circum-Caribbean magmatic arcs. Short-lived, ~60–45 Ma arc-like magmatism in the Central Cordillera of Colombia was emplaced in a thickened continental crust due to the oblique subduction of the Caribbean oceanic plate underneath South America, as suggested by the high Sr/Y ratios. Conversely, the Panama Arc, and its poorly explored extension in the northwestern segment of the Western Cordillera of Colombia document a major phase of tholeiitic to calc-alkaline arc magmatism between ~71 Ma and ~34 Ma, mostly derived from a hydrated mantle wedge, and emplaced in an oceanic plateau crust. This arc record a major phase of magmatic activity between 40 Ma and 50 Ma that can be associated to changes in the convergence direction and subduction rates of the Farallon plate. Farther to the south, in the Pacific region of Colombia, Eocene arc-related rocks from the Timbiqui Complex show a geochemical signature that suggests a magmatic origin from melting of both a subduction-modified mantle and lower tectonically thickened crust. A possible interpretation for the Pacific and Western Colombia-Panama Arc systems, and its analogous in Ecuador, recall an Aleutian-type convergent margin in which the continental arc laterally switches to a purely oceanic system along the trailing edge of the Caribbean plate as consequence of eastward subduction of the Farallon plate. Highlights • We present a compiled extensive geochemical, geochronological and isotopic dataset. • New Hf-Nd-Sr-Pb isotopes and geochemical analyses are included. • The Paleogene arcs of the Colombian Andes and Panama show contrasting genesis. • Magmatism likely resulted from complex regional-scale plate kinematics. [ABSTRACT FROM AUTHOR]

Abstract: Southern Central America is a Late Mesozoic/Cenozoic island arc that evolved in response to the subduction of the Farallón Plate beneath the Caribbean Plate in the Late Cretaceous and, from the Oligocene, the Cocos and Nazca Plates. Southern Central America is one of the best studied convergent margins in the world. The aim of this paper is to review the sedimentary and structural evolution of arc‐related sedimentary basins in southern Central America, and to show how the arc developed from a pre‐extensional intra‐oceanic island arc into a doubly‐vergent, subduction orogen. The Cenozoic sedimentary history of southern Central America is placed into the plate tectonic context of existing Caribbean Plate models. From regional basin analysis, the evolution of the southern Central American island arc is subdivided into three phases: (i) non‐extensional stage during the Campanian; (ii) extensional phase during the Maastrichtian‐Oligocene with rapid basin subsidence and deposition of arc‐related, clastic sediments; and (iii) doubly‐vergent, compressional arc phase along the 280 km long southern Costa Rican arc segment related to either oblique subduction of the Nazca plate, west‐to‐east passage of the Nazca–Cocos–Caribbean triple junction, or the subduction of rough oceanic crust of the Cocos Plate. The Pleistocene subduction of the Cocos Ridge contributed to the contraction but was not the primary driver. The architecture of the arc‐related sedimentary basin‐fills has been controlled by four factors: (i) subsidence caused by tectonic mechanisms, linked to the angle and morphology of the incoming plate, as shown by the fact that subduction of aseismic ridges and slab segments with rough crust were important drivers for subduction erosion, controlling the shape of forearc and trench‐slope basins, the lifespan of sedimentary basins, and the subsidence and uplift patterns; (ii) subsidence caused by slab rollback and resulting trench retreat; (iii) eustatic sea‐level changes; and (iv) sediment dispersal systems. [ABSTRACT FROM AUTHOR]

The reconstruction of the tectonic evolution of the oceanic crust, including the recognition of ancient oceanic plumes and the differentiation between multiple and single oceanic arcs, relies on the paleogeographic analysis of accreted oceanic fragments found in orogenic belts. Here we present paleomagnetic and gravity data from Cretaceous oceanic basaltic and gabbroic rocks, the continental metamorphic basement, and their associated cover from northwestern Colombia. Based on regional scale tectonic reconstructions and geochemical constraints, such rocks have been interpreted as remnants of an oceanic large igneous province formed in southern latitudes, which was accreted to the sialic continental margin during the Late Cretaceous. Gravity analyses suggest the existence of a coherent high density segment separated by major suture zones from a lower density material related to the continental crust and/or thick sedimentary sequences trapped during collision. A characteristic paleomagnetic direction in Early and Late Cretaceous oceanic volcano-plutonic rocks, revealing a southeastern declination (D) and a negative inclination (I), may be interpreted in two different ways: (1a primary magnetization (tilt-corrected direction D = 130.3°, I = -23.3°, k = 23.4, α95 = 26.4°), suggesting clockwise rotation around 130°, and magnetization acquired in southern latitudes (range of 4°S to 21°S); or (2) a remagnetization event during a reverse interval of the Earth’s magnetic field in the Cenozoic (in situ direction D = 128.7°, I = -6.2°, k = 23.1, α95 = 26.1°), suggesting a counter-clockwise rotation around 50°. The first scenario seems more plausible, as it is consistent with previous paleomagnetic studies at other localities; it is compatible with a southern paleogeography for this block, and when integrated with other regional geological and paleomagnetic studies, supports a southern Pacific origin of a major oceanic block, formed as a part of a broader Cretaceous plateau that may have extended south or southwest of Galapagos. After its initial accretion, this block was subsequently fragmented due to the oblique SW-NE approach to the continental margin during the Late Cretaceous. [ABSTRACT FROM AUTHOR]

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We document patterns of coordinated dispersal over evolutionary time frames in heroine cichlids and poeciliine live-bearers, the two most species-rich clades of freshwater fishes in the Caribbean basin. Observed dispersal rate (DO) values were estimated from time-calibrated molecular phylogenies in LAGRANGE+, a modified version of the ML-based parametric biogeographic program LAGRANGE. DO is measured in units of "wallaces" (wa) as the number of biogeographic range-expansion events per million years. DO estimates were generated on a dynamic paleogeographic landscape of five areas over three time intervals from Upper Cretaceous to Recent. Expected dispersal rate (DE) values were generated from alternative paleogeographic models, with dispersal rates proportional to target area and source-river discharge volume, and inversely proportional to paleogeographic distance. Correlations between DO and DE were used to assess the relative contributions of these three biogeographic parameters. DO estimates imply a persistent dispersal corridor across the Eastern (Antillean) margin of the Caribbean plate, under the influence of prevailing and perennial riverine discharge vectors such as the Proto-Orinoco-Amazon river. Ancestral area estimation places the earliest colonizations of the Greater Antilles and Central America during the Paleocene-Eocene (ca. 58-45 Ma), potentially during the existence of an incomplete Paleogene Arc (~59 Ma) or Lesser Antilles Arc (~45 Ma), but predating the GAARlandia land bridge (~34-33 Ma). Paleogeographic distance is the single best predictor of DO. TheWestern (Central American) platemargin did not serve as a dispersal corridor until the LateNeogene (12-0 Ma), and contributed relatively little to the formation of modern distributions. [ABSTRACT FROM AUTHOR]

Although recent years have seen an increase in genetic analyses that identify new species of cephalopods and phylogeographic patterns, the loliginid squid of South America remain one of the least studied groups. The suggestion that Doryteuthis plei may represent distinct lineages within its extensive distribution along the western Atlantic coasts from Cape Hatteras, USA (36°N) to northern Argentina (35°S) is consistent with significant variation in a number of environmental variables along this range including in both temperature and salinity. In the present study D. plei samples were obtained from a large number of localities along the western Atlantic coasts to investigate the distribution of these possible species in a phylogeographic context. Phylogeographic analyses were performed using the mitochondrial Cytochrome Oxidase I gene and nuclear Rhodopsin gene. Divergence times were estimated using Bayesian strict clock dating with calibrations based on fossil records for divergence from the lineage containing Vampyroteuthis infernalis (162 mya), the probable origins of the North American loliginids (45 mya), and the European loliginids (20 mya) and fossil statolith from Doryteuthis opalescens (3 mya). Our results suggest a deep genetic divergence within Doryteuthis plei . The currently described specie consists of two genetically distinct clades (pair-wise genetic divergence of between 7.7 and 9.1%). One clade composed of individuals collected in northwestern Atlantic and Central Caribbean Atlantic waters and the other from southwestern Atlantic waters. The divergence time and sampling locations suggest the speciation process at approximately 16 Mya, which is in full agreement with the middle Miocene orogeny of the Caribbean plate, ending up with the formation of the Lesser Antilles and the adjacent subduction zone, coinciding with a particularly low global sea level, resulting in the practical absence of continental shelves at the area, and therefore an effective geographic barrier for D. plei . Furthermore, this study also provides evidence of previously undocumented sub-population structuring in the Gulf of Mexico. [ABSTRACT FROM AUTHOR]

Isla del Coco is the only land mass of the Cocos Plate that emerges above sea level. This makes it the only place where Cocos Plate motion can be measured using Global Navigation Satellite System (GNSS) monitoring. Global Positioning System (GPS) observations have been carried out sporadically over more than two decades on Isla del Coco, allowing precise measurement of the motion of the Cocos Plate. Recently, in May 2011, a continuous GPS station was built and instrumented at Isla del Coco, in Wafer Bay, by OVSICORI-UNA and UNAVCO, as part of the COCONet regional GNSS network. Position time series from this CGPS station (ISCO: Isla del Coco) show a steady motion of Isla del Coco at a speed of 90.9±1.5mm/yr in the N35oE direction in ITRF2008 and convergence with the Caribbean Plate at 78±1mm/yr. This result is consistent with the findings of the earliest GPS studies, and agrees within uncertainty with the estimated convergence rate of 76.4±x mm/ yr of the MORVEL plate motion model. MORVEL is based on an average over the last 780,000 years, and our result suggests that Cocos-Caribbean plate motions have been constant over that time interval.La Isla del Coco es la única porción emergida en la placa del Coco. Esta condición la hace el único lugar donde se puede medir, usando Sistemas de Navegación Global por Satélite (GNSS), la velocidad de dicha placa. Las mediciones con GPS en la Isla del Coco se han realizado por más de dos décadas, permitiendo obtener velocidades precisas. En mayo del 2001 se instaló una estación continua de GPS en la Isla del Coco como parte, tanto de la Red Regional de GNSS COCONet, como del Sistema de Monitoreo Geodinámico de Nicoya (SISMOGENICO). Resultados de esta estación continua muestran movimiento continuo de la Isla del Coco, con respecto a ITRF2008, a una velocidad de 90.9±1.5mm/año con dirección N35oE y convergencia con la placa del Caribe a 78±1mm/año. Estas velocidades son consistentes con las obtenidas por MORVEL, un modelo geológico de velocidades de placas representativo de los últimos 780,000 años, y sugieren que la convergencia de estas placas se ha mantenido constante durante ese lapso de tiempo.

Along the Isthmus of Panama 23 paleomagnetic sites were sampled in order to determine preliminary block rotations and paleolatitudinal movements. The lithology selected for this research corresponds to volcanic and sedimentary rocks with ages ranging from Upper Cretaceous to Pleistocene. Counterclockwise vertical axis rotations were uncovered in Paleocene and Oligocene units separated by a sinistral fault. Mean directions of two sites collected in Cenozoic rocks to the north of the fault are westerly (D 275.4, I -20.8, k 20.46, a95 10.9; D 264.6, I 5.3, k 292.35, a95 3.5), whereas the mean direction uncovered in one site collected in Oligocene rocks to the south of the fault yields a northward declination and positive inclination (D 346.3, I 14.3, k 18.43, a95 14.4). Vertical axis rotation of 81.7º ± 13.3º, of the Paleocene rocks with respect to the Oligocene rock. Cenozoic sites record the northward path of the trailing edge of the Caribbean plate, from 10.8ºS for Paleocene to 6.6ºN for Oligocene. However, more sites are needed to be collected in order to better constraint this northward translation. Components isolated in El Valle volcano and Canal areas using Middle Miocene to Pleistocene rocks, indicate normal and reverse directions similar to the current direction of the Earth magnetic field. Therefore, no major latitudinal displacement of the Panama Isthmus has occurred during the Neogene. Northward migration of the Panama arc is consistent with the Pacific origin of the Caribbean plate and counter-clockwise vertical axis rotation of several blocks in Panama could be related with the South American Plate collision since Pliocene.

We investigate the differences and similarities in Cocos–North America and Cocos–Caribbean convergence, reflected by seismicity and seismic moment. We use well-located hypocenters of earthquakes in the convergence margin, as well as within the subducted slab. We sort these data by number of events in the two converging margins, and by their magnitudes. We also use this database to determine an improved geometric model of the subducted slab. We find a shallow-dipping subducting Cocos plate underneath North America and a steeper dip slab under the Caribbean plate. The transition between them appears to be smooth. Centroid Moment tensor solutions indicate that almost all of the thrust-faulting earthquakes along Cocos–North America take place at shallow depths. Normal-faulting events along this margin only take place to depths of 100 km. Thrust- and normal-faulting events take place at all depths along the Cocos–Caribbean margin. Cummulative scalar seismic moment for shallow, thrust-faulting events, is larger along Cocos–North America. T axes of intermediate-depth, normal- and thrust-faulting events show that the subducted Cocos plate is in maximum tension along the direction of maximum dip. Azimuth of earthquake slip vectors for shallow events along the Cocos–North America margin agree well with the direction of plate convergence. They do not agree along the Cocos–Caribbean margin; instead, agreement is found with Cocos–North America relative plate motion. Compensated Linear Vector Dipole (CLVD) ratio, which measures how different a seismic source is from a pure double-couple, along both margins is inversely proportional to scalar seismic moment, indicating that for larger magnitudes rupture is closer to a double-couple mechanism than at smaller moments. [ABSTRACT FROM AUTHOR]

The M 7.0 Haiti earthquake of 2010 in the Greater Antilles is a reminder that the northeastern Caribbean is at a high risk for seismic and tsunami hazards. The Greater Antilles consist of the Hispaniola microplate to the west and Puerto Rico-Virgin Islands to the east and are situated between two subduction zones with the Puerto Rico Trench to the north and the Muertos Trough to the south. Although there is no active volcanism on Puerto Rico, earthquake depths and previous seismic tomography results imply that the slabs of Caribbean and North American Plates exist at depth. However, how far the east Muertos Trough subduction of the North Caribbean Plate has extended has not been fully addressed. In addition, the Puerto Rico-Virgin Islands are bounded by extensional regimes to both the west (Mona Rift) and east (Anegada Passage). The cause of the extension is still under debate. In this paper, we use new 3D seismic tomography and gravity data to carry out an integrated study of the geometry of the subducting slabs of the North American and North Caribbean Plates in the Puerto Rico-Virgin Islands area. The results indicate that both slabs have an increase of dip westward, which is strongly controlled by the subduction rollback of the North American Plate. These variations affected the tectonic evolution of the Puerto Rico-Virgin Islands. Thus, the results of this research advance our understanding of the kinematic evolution of the Puerto Rico-Virgin Islands and associated natural hazards. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]