The ophiolitic Villa Clara serpentinite-matrix mélange, central Cuba, forms part of the large ophiolitic belt of the Greater Antilles. The composition of ultramafic and mafic rocks allows classifying them into two main groups, revealing a complex multi-stage formation of oceanic lithosphere in varied tectonic settings: i) group 1 matches fertile MORB-like mantle typical of abyssal/transform fault peridotites, while ii) group 2 shows characteristics of refractory mantle-wedge forearc peridotites. These features are consistent with moderate extent of partial melting (4–8%) of depleted mantle at a mid-ocean ridge setting that created residual abyssal peridotite (group 1) and intense remelting (14–18%) of the latter in a forearc setting that created highly refractory peridotite (group 2). The elemental and isotopic characteristics of groups 1 and 2 serpentinites denote the influx of fluids evolved from the subducting slab. Mafic rocks appear as variably sized tectonic blocks within serpentinite that underwent variable alteration at low pressure. Immobile element concentrations allow identifying two main groups: i) group 1 is consistent with forearc basalts formed during the second stage of melting of (abyssal) peridotite, while ii) group 2 has a compositional pattern like island-arc tholeiitic basalts. A geodynamic evolution from abyssal to forearc settings is presented to explain the nature of the oceanic lithosphere of the Villa Clara ophiolitic bodies and ensuing serpentinization and mélange formation. This model may explain other ophiolitic bodies of the Caribbean arc in Cuba, Dominican Republic and Puerto Rico and elsewhere formed in abyssal/transform fault or forearc settings.

The GAARlandia hypothesis has produced vigorous debate among biologists regarding whether now-submerged landforms that existed in the Caribbean region during the late Paleogene might have acted as a barrier for marine organisms and as a bridge for terrestrial biotas migrating from South America into the Greater Antilles. This concept derived from the hypothesized emergence history of the Aves Ridge. In the quarter century since GAARlandia was first proposed, new paleontological, geological and geophysical information has greatly extended the database available. Here we reaffirm that GAARlandia was a positive topographic feature from middle Eocene, and was exposed above sea level between late Eocene and early Oligocene when it facilitated biotic colonization of the northern Greater Antilles and their satellite islands, whether as a series of closely spaced islands or as a continuous peninsula projecting from northeastern South America along the crown of the rise.

Two fragmentary Plesiosauria (marine reptile) flippers are described from the Late Jurassic (Oxfordian) marine deposits of western Cuba. The specimens, despite being fragmentary and remineralized, can be assigned to the Plesiosauria based on the distinctive morphology of the phalanges. These remains, originally discovered during the 20th century, had not been previously studied. They provide another clue in the understanding of the Late Jurassic vertebrate fossil record of Cuba and the paleo-Caribbean.

En el territorio de la República de Cuba y áreas adyacentes ocurren sismos con magnitudes de 1 a 3, que eventualmente han alcanzado hasta 8. Aunque los de magnitud mayor de 3 generalmente son perceptibles, los que suelen ocasionar daños son los de magnitud mayor de 5; no obstante, su impacto negativo depende en gran medida del estado de la infraestructura construida y de la cercanía del foco. El presente ensayo constituye una contribución a la percepción del riesgo en la población cubana e introduce el concepto ciudades en alerta sísmica, que se fundamenta en el principio de que donde ocurrieron eventos sísmicos destructivos en el pasado, es muy probable que se repitan en el futuro, a menos que la infraestructura construida se hubiese mejorado sustancialmente. Se propone, además, un conjunto de recomendaciones para las ciudades cubanas definidas en alerta sísmica.

The Hatillo Limestone and the underlying Los Ranchos Formation are exposed over an east-west distance of 100 km in the eastern Dominican Republic. The lowermost portion of the Hatillo Limestone in the Pueblo Viejo district contains a Late Lower Albian fossil assemblage including corals and rudist bivalves indicative of a near-shore reef environment. Diamond drilling in the Pueblo Viejo district and exposures in the open pits show that the Hatillo Limestone conformably overlies the Early Cretaceous Los Ranchos Formation. Volcanogenic massive sulfide beds, exposed in the Moore pit, provide evidence for an Early Cretaceous, syn-mineralization paleosurface. Altered and mineralized clasts in the epiclastic, sedimentary host-rock section at the Pueblo Viejo mine indicate that the ore deposits were open to erosion during hydrothermal alteration and mineralization. The Hatillo Limestone did not overlie the ore deposits during the mineralizing event and, consequently, could not have acted as an impermeable cap to ascending hydrothermal fluids. Intra-oceanic island arc volcanism (Los Ranchos Formation) overlapped at the Aptian–Albian boundary (112 Ma) with a marginal fringing reef (basal Hatillo Limestone). The marginal reef gradually gave way to deeper-water facies as Hatillo Limestone deposition progressed through the middle Albian. Low-angle reverse faulting, penetrative deformation, and metamorphic recrystallization affected the Hatillo Limestone as well as the Los Ranchos and Maimón formations during the Late Cretaceous. Deformation intensity and metamorphic grade progressed from incipient metamorphism in the Pueblo Viejo district to schists in the Maimón Formation to amphibolite near a faulted contact with the Loma Caribe peridotite.

Amber from the Dominican Republic is famous for the high quality, frequency, and diversity of organic fossils found as inclusions in this mineral (Grimaldi, 1996; Poinar & Poinar, 1999). However, its geological age of origin remains a continuing source of controversy. Over the years a wide variety of age estimates have been made for occurrences of Dominican amber, ranging from Cretaceous (Brouwer & Brouwer, 1982) to Late Eocene (Lambert et al., 1985) to pre-Lower Miocene (Baroni-Urbani & Saunders, 1982). Some authors have also favored a spread of ages that covers much of the Cenozoic (e.g., 40 or 45 Ma to 15 Ma; Poinar & Poinar, 1999). Iturralde-Vinent & MacPhee (1996) attempted to resolve discrepancies in age assignments by taking a multi-pronged analytical approach which yielded a best-fit estimate of mid-Miocene age (20–15 Ma). This estimate has been widely accepted and additionally corroborated by new studies (Iturralde-Vinent, 2001; Ortega-Ariza et al., 2015). However, Braga et al. (2012) have challenged the assessment of Iturralde-Vinent & MacPhee (1996) by arguing for a Pliocene–early Pleistocene date for the amber-bearing Yanigua Formation. Here we address the sources of disagreement and suggest a solution.

Amber from the Dominican Republic is famous for the high quality, frequency, and diversity of organic fossils found as inclusions in this mineral (Grimaldi, 1996; Poinar & Poinar, 1999). However, its geological age of origin remains a continuing source of controversy. Over the years a wide variety of age estimates have been made for occurrences of Dominican amber, ranging from Cretaceous (Brouwer & Brouwer, 1982) to Late Eocene (Lambert et al., 1985) to pre-Lower Miocene (Baroni-Urbani & Saunders, 1982). Some authors have also favored a spread of ages that covers much of the Cenozoic (e.g., 40 or 45 Ma to 15 Ma; Poinar & Poinar, 1999). Iturralde-Vinent & MacPhee (1996) attempted to resolve discrepancies in age assignments by taking a multi-pronged analytical approach which yielded a best-fit estimate of mid-Miocene age (20–15 Ma). This estimate has been widely accepted and additionally corroborated by new studies (Iturralde-Vinent, 2001; Ortega-Ariza et al., 2015). However, Braga et al. (2012) have challenged the assessment of Iturralde-Vinent & MacPhee (1996) by arguing for a Pliocene–early Pleistocene date for the amber-bearing Yanigua Formation. Here we address the sources of disagreement and suggest a solution.

Cuba is the largest island in the Greater Antilles, and its geology records three important episodes: (1) the Jurassic breakup of North and South America (Pangea) and associated passive margin and oceanic sedimentary and magmatic evolution; (2) the sedimentary, magmatic, and metamorphic evolution of an intra-oceanic Cretaceous-Paleogene ophiolite-arc complex; and (3) the Paleogene "soft collision" and transfer of the NW Caribbean plate (and Cuba) to the North American plate.Thick sequences of Jurassic-Cretaceous strata (conglomerates, sandstones, limestones, dolostones, shales) and interlayered basaltic rocks characterize passive margin sequences preserved in the Guaniguanico terrane (western Cuba, related to the Mayan passive margin and the Gulf of Mexico) and the Bahamas Platform borderlands (north of Cuba).Passive margin deposition ceased in latest Cretaceous time, when increasing relief of accreted (overriding) oceanic arc and ophiolite complexes shed coarse sediments (olistostrome and flysch), followed by carbonate deposition.Fragments of the intervening oceanic lithosphere (Proto-Caribbean, connected to the Central Atlantic) and fore-and back-arc oceanic lithosphere (Caribbean, of Pacific origin) occur as tectonic fragments detached from the ophiolitic units, including serpentinized harzburgites and dunites, banded and isotropic gabbros, basalts (tholeiitic and fore-arc basalts, locally with boninites) and Late Jurassic (Tithonian) through Late Cretaceous (Coniacian and younger) oceanic sediments.Arc activity in the Cuban segment of the Greater Antilles produced sedimentary, volcanic, and plutonic rocks during Cretaceous times (ca.135-70 Ma).A new arc developed in eastern Cuba during Paleocene-middle Eocene times.Cuban arc sequences include island-arc tholeiitic, calcalkaline, and alkaline bimodal suites of volcanic and plutonic rocks.Remnants of Proto-Caribbean oceanic lithosphere occur as exhumed mélangebearing eclogite-, blueschist-, and garnet-amphibolite-facies tectonic blocks (oldest age ca.120 Ma) within a serpentinite matrix intercalated with, or at the base of, the overthrusted ophiolitic bodies.Cuban Cretaceous arc magmatic activity ended dueThe geology of Cuba: A brief overview and synthesis to the subduction of Proto-Caribbean passive margin sequences of the Caribeana terrane, an offshore protuberance of Yucatan.This event formed strongly deformed high-pressure metasedimentary and metaigneous rocks at ca. 70 Ma, when the Caribbean plate began to collide with North America.The collision, which included overriding of the ophiolitic and arc units over both subducted and unsubducted passive margin sequences, also produced synorogenic basins and filled them, a process that continued until ca.40 Ma.This foldbelt was succeeded by local uplift and subsidence to form late Eocene-Recent unconformable post-orogenic continental basins.

Two types of Al-rich chromitite bodies are present within the mantle-crust transition zone (MTZ) at Loma Iguana, Camaguey ophiolitic massif, Cuba: i) dunite-hosted chromitites and ii) layered gabbro-hosted chromitites. Dunite-hosted chromitites show petrologic and textural features similar to Al-rich chromitite bodies typical of the upper most part of MTZ in ophiolitic complexes worldwide, while gabbro-hosted chromitites represent a rare type of ophiolitic chromitite. The latter are small (<20 cm in thickness) irregular to vein shaped bodies hosted within gabbroic cumulates at the base of the plutonic crust. These chromitites are composed of euhedral to subhedral poikilitic grains of Cr-spinel, which contain inclusions of plagioclase, clinopyroxene and amphiboles. Cr-spinel is strongly enriched in Al2O3 (up to 46 wt%) and TiO2 (up to 0.7 wt%). At the contact between chromitite and layered grabbro, chromitite systematically replaces plagioclase and clinopyroxene of the gabbro. Suggesting crystallization of high-Al chromitite was controlled by the breakdown of plagioclase/clinopyroxene from the host gabbro, after assimilation (and melting) of lower-crustal by basaltic melts.

El trabajo presenta una serie de mapas paleogeograficos que ilustran la formacion y evolucion del Caribe desde el Triasico Tardio al presente y se discuten sus implicaciones biogeograficas. Se demuestra que el Caribe desde su propia formacion ha jugado un papel trascendental controlando la circulacion de las aguas oceanicas, moderando el clima terrestre, y determinando las posibilidades de intercambio biotico entre los ecosistemas de las tierras y mares circundantes. La formacion de un pasaje marino en el mesozoico entre Tethys occidental y Pacifico oriental a lo largo de Pangea centro-oriental, ha sido postulado desde el Jurasico Inferior (Hettangiano-Pliensbachiano) de acuerdo a algunas tesis biogeograficas, pero faltan los datos estratigraficos que le sirvan de soporte a esta propuesta. Quizas desde el Bathoniano (≈164 Ma), pero ciertamente desde el Oxfordiano (≈154 Ma), los datos de la estratigrafia indican que esta conexion era totalmente funcional y la corriente marina Circum-Tropical estaba activa. La dispersion de las biotas terrestres entre Laurasia occidental (America del Norte) y Gondwana occidental (America del Sur) se interrumpio desde el Calloviano, cuando entre esos continentes se formo una faja de mar que los separo. Posteriormente hubo intercambios de tetrapodos entre America del Norte y America del Sur, a traves de un puente terrestre que los conecto brevemente durante el Campaniano tardio y el Maastrichtiano (≈75-65 Ma), y a partir del Plioceno (2.5-2.3 Ma). Las evidencias de que haya existido un puente intracontinental al final del Mioceno Medio aun es ambigua. Desde la formacion del primer archipielago de islas volcanicas en el area del Caribe, aproximadamente en la transicion jurasico-cretacico (≈141 Ma), en el escenario paleogeografico del Caribe y su entorno han estado presentes islas volcanicas, bajos, y crestas. Pero aquellas tierras emergidas fueron generalmente efimeras, ya que se sumergieron apenas unos pocos millones de anos despues de emergidas; y si soportaron alguna biota, estas desaparecieron junto con las islas. Solo a partir del eoceno medio (≈40 Ma) han existido tierras permanentemente emergidas en el marco geografico del Caribe, que proveen el substrato necesario para la formacion y desarrollo de las biotas terrestres actuales. De particular importancia biogeografica en este periodo de tiempo, fue la formacion de una extensa cresta emergida (Gaarlandia), que hace 35-33 Ma unio brevemente America del Sur con los nucleos de las futuras Antillas Mayores, y el desarrollo de los nucleos terrestres antillanos hasta el presente. Palabras claves : paleogeografia, paleoceanografia, biogeografia, Caribe, Cuba, Mesozoico, Cenozoico. ABSTRACT Since latest Triassic the Caribbean started to be formed as a system of Jurassic rift valleys within west-central Pangaea, later evolving into a mediterranean sea where distinct volcanic and non volcanic island evolved. Since its very early formation this sea has been playing an important roll controlling the historical patterns of ocean water circulation, moderating the world climate, and determining the possibilities of biotic exchange of the surrounding terrestrial and marine ecosystems. The formation of a Mesozoic marine seaway between the western Tethys and the eastern Pacific, across west-central Pangaea, has been postulated for the Early Jurassic (Hettangian-Pliensbachian) according to biogeographic thesis, but supporting stratigraphic data is lacking. Probably since the Bathonian but certainly since the Oxfordian, the stratigraphic records indicate that this connection was fully functional and the Circum Tropical marine current was active. Overland dispersal between western Laurasia (North America) and western Gondwana (South America) has been interrupted since the Callovian when the continents were separated by a marine gap. Later, a connecting landbridge may have been present during the latest Campanian/Maastrichtian (≈75-65 Ma), and since the Plio- Pleistocene (2.5-2.3 Ma). Evidence for a precursor bridge late in the Middle Miocene is ambiguous at this time. Since the formation of the first volcanic archipelago within the Caribbean realm, at about the Jurassic-Cretaceous transition, volcanic islands, shallow banks, and ridges have been present in the paleogeographic scenario of the area. But these lands were generally ephemeral, as they lasted just a few million years. Only after the Middle Eocene (<40 Ma ago) permanent lands were present within the Caribbean geographic scenario, providing the substrates for the formation and development of the present terrestrial biota. Key words: paleogeography, paleoceanography, biogeography, Caribe, Cuba, Mesozoic, Cenozoic.

Thermobarometric estimates and predictions of theoretical and experimental isochemical P-T phase diagrams for epidote±garnet amphibolite blocks from the serpentinite mélange of La Corea (eastern Cuba) indicate partial melting of subducted oceanic lithosphere occurred at peak metamorphic conditions of ca. 700 °C and 14 to 15 kbar. These anomalously high geothermal conditions suggest onset of subduction of young oceanic lithosphere of the Proto-Caribbean. The amphibolites have basaltic composition and MORB affinity. Partial melting produced tonalitic-trondhjemitic-granitic melts that crystallized at depth associated with the amphibolites. Calculated retrograde conditions for the amphibolites (450 °C and 8-10 kbar) indicate counterclockwise P-T paths during exhumation in the subduction channel, in agreement with published predictions on thermo-mechanical modeling of onset of subduction of young lithosphere. These findings have important consequences for the plate tectonic configuration of the Caribbean realm since they corroborate the existence of fragments of early subducted young oceanic lithosphere in the eastern Cuba mélanges that indicate subduction of an oceanic ridge during mid-Cretaceous times.

A new jadeitite jade locality has been discovered in the serpentinite-matrix subduction mélange of the Sierra del Convento (eastern Cuba) in a context associated with tectonic blocks of garnet-epidote amphibolite, tonalitic–trondhjemitic epidote gneiss, and blueschist. The mineral assemblages of jadeitite jade and jadeite rocks are varied and include combinations of jadeite, omphacite, albite, paragonite, analcime, clinozoisite-epidote, apatite, phlogopite, phengite, chlorite, glaucophane, titanite, rutile, zircon, and quartz formed during various stages in their P–T evolution. Field relationships are obscure, but some samples made almost exclusively of jadeite show evidence of crystallization from fluid in veins. In one of these samples studied in detail jadeite shows complex textural and chemical characteristics (including oscillatory zoning) that denote growth in a changing chemical medium. It is proposed that interaction of an Al–Na rich fluid with ultramafic rocks produced Al–Na–Mg–Ca fluids of varying composition. Episodic infiltration of these fluids, as a result of episodic opening of the veins, developed oscillatory zoning by direct precipitation from fluid and after reaction of fluid with pre-existing jadeite. The latest infiltrating fluids were richer in Mg–Ca, favouring the formation of omphacite and Mg–Ca rich jadeite in open voids and the replacement of earlier jadeite by fine-grained omphacite + jadeite at 550–560°C. This new occurrence of jadeite in Cuba opens important perspectives for archeological studies of pre-Columbian jade artifacts in the Caribbean region.

The deformation history of sedimentary units incorporated in the North Cuban fold and thrust belt in the Paleocene to middle–late Eocene was associated with major shortening between the Caribbean and North American plates. This led to the formation of an intensely deformed tectonic pile comprising from top to bottom of a volcanic arc nappe, a deformed mafic–ultramafic complex with Mesozoic ophiolite components and a serpentinitic mélange with blocks of sedimentary (the Placetas belt) and metamorphic rocks; and the structurally lower unit composed of folded and thrusted sediments of the southern promontory of the Bahamas platform. In this paper we study the deformation history of sedimentary units incorporated in the North Cuban fold and thrust belt associated with this shortening history. We find that the occurrences of the Placetas sedimentary rocks within the foliated serpentinite mélange show varying styles and intensity of deformation, and varying number of deformation phases. They form isolated blocks within the serpentinite mélange and do not represent a coherent nappe underlying the allochtonous mafic–ultramafic complex. The deformation of the Remedios belt, part of the Bahamas platform, underwent a single phase of folding and thrusting, with shortening perpendicular to the plate contact. This folding occurred in the middle to late Eocene and marks the arrest of subduction and arc–continent collision. We find no evidence for a component of strike-slip during collision. The volcanic arc is thrusted upon the mafic–ultramafic complex, and the original forearc ophiolite appears to be shortened. This shortening may attest to a period of subduction erosion. Thrusting of the volcanic arc led to deposition of the Paleocene-lower Eocene Taguasco olistostrome which may date this event. We show that careful analysis of the complexly deformed Cuban fold and thrust belt may allow identification of subduction erosion and subduction accretion episodes. Expanding the analysis carried out in this paper to the scale of the northern Caribbean fold and thrust belt may provide a new and independent geological tool to constrain the geodynamic processes associated with subduction and arc–continent collision along the northern Caribbean margin.

Metasedimentary complexes dispersed all along the northwestern branch of the Caribbean orogenic belt between Yucatan and the Virgin Islands provide evidence for a major tectonic event of latest Cretaceous (Late Campanian-Early Paleocene) age that played a key role in the evolution of the Caribbean realm. During the northeastward Cretaceous drift of the Caribbean plate from the Pacific, the leading edge of the plate encountered a sedimentary prism that extended southeastward into the Proto-Caribbean realm from the southeastern edge of the Maya Block. Latest Cretaceous subduction of this Mesozoic sedimentary suite, dubbed here "Caribeana," formed metamorphic complexes (i.e., East Yucatán, Cangre, Pinos, Escambray, Guayabal, Asunción, Samaná, and Puerto Rico Trench terranes). This latest Cretaceous subduction/accretion event triggered the interruption or attenuation of the activity of the Cretaceous volcanic arc and the tectonic emplacement of ophiolites and subduction channel complexes along the leading edge of the Caribbean plate. Flat subduction of the Proto-Caribbean ensued during the Maastrichtian-Eocene in the western segment of the leading edge of the Caribbean plate, whereas normal-angle subduction and volcanic arc magmatism continued during the same time span in the eastern segment. The metamorphic complexes evolved differently since the Maastrichtian. As a consequence of the development of the Yucatan Basin in the western part of the orogenic belt, the Pinos, Escambray, and probably the Guayabal terranes were exhumed in an intra-arc environment, whereas the East Yucatan(?), Cangre, Asunción, Samaná, and Puerto Rico Trench terranes were exhumed in a fore-arc setting.

Lateral lithological, compositional, and grain size variations in the Peñalver Formation in northwestern Cuba, which is a Cretaceous/Tertiary (K/T) boundary deposit accumulated on the northwestern slope of the extinct Cretaceous Cuban arc and distributed over an area of 150km, are examined in order to investigate the influence of a tsunami on the deep-sea bed. The lower part of the Peñalver Formation is composed of calcirudite containing grains derived from a shallow platform. It is considered to have been deposited by debris flows from the shallow carbonate platform triggered by the impact of the seismic wave. The upper part of the formation is composed of calcarenite to calcilutite hemipelagic to pelagic sediments. This has a distinctly different source to the lower part and is considered as having been formed under the influence of tsunami waves, judging from its regional homogeneity and the presence of serpentine lithic grains that were probably transported from central to eastern Cuba by a westward flowing water mass. An erosional surface between the two parts, together with sedimentary structures in the upper part indicative of current influence is more common with decreasing presumed depositional depth, which can be interpreted as stronger tsunami effect at the shallower depths. In addition, compositional and grain size oscillations that repeated >6 to 10 times are observed in the upper part, which may reflect repeated lateral injection of the sediments eroded from the shelf to the upper slope of the depositional basin by backwash of successive tsunami waves into the dense sediment suspended cloud that was formed by the first tsunami.

The sedimentary rocks intercalated in volcanic and metavolcanic sections of Mayarí-Baracoa and Sierra del Purial Mountains (Eastern Cuba), yielded Cretaceous through Danian microfossils. In the Mayarí Mountains the Téneme Fm consists of basalts and hyaloclastites with minor intercalations of well-bedded foliated limestone and shaly limestone that in the type area contain a Turonian or early Coniacian planktonic foraminifera assemblage. In the Morel area (Moa-Baracoa massif), back-arc pillow basalts with ribbon cherts include a late Turonian or Coniacian limestone bed intercalated with interbedded organic-rich calcareous shales near the top. The upper part of the Coniacian (?)-Campanian Santo Domingo Fm crops out west of Moa and it consists of finegrained well-bedded volcaniclastic rocks with two intercalated lenses of coarse-grained impure biocalcirudites to biocalcarenites. These rocks yielded a mixed penecontemporaneous planktonic and benthonic microfossil assemblage attributed to the lower part of the late Campanian (Globotruncanita calcarata Zone). At Sierra del Purial, crystalline limestones embedded within the metavulcano-sedimentary Río Baracoa section (Purial metamorphic complex) yielded Campanian microfossils. The Maastrichtian Yaguaneque (=Cañas) limestones crop out extensively in both Mayarí-Baracoa and Purial Mountains. All the formations previously mentioned unconformably overlie and tectonically intermingle with the late Maastrichtian-early Danian clastic rocks of the Mícara and La Picota Fms. Our new dates demonstrate that in the Greater Antilles the PIA (Primitive Island Arc-tholeiite) recorded by the Téneme Fm would be Late Cretaceous in age in opposition to the Lower Cretaceous age proposed for the PIA basalts. The protolith of the Purial metamorphic complex is probably Maastrichtian-early Danian, but certainly Campanian and older in age. This fact suggests that the metamorphism that affected the Purial rocks took place probably in the late Maastrichtian and was coeval with the detachment, exhumation and emplacement of mafic-ultramafic thrust-sheet bodies. This event recorded in Eastern Cuba/Western Hispaniola and Guatemala might have been related to the insertion of thick oceanic ridges into the subduction zone.

Since the latest Triassic, the Caribbean started to form as a system of rift valleys within westcentral Pangea, later evolving into a mediterranean sea where distinct volcanic and non-volcanic islands evolved. Since its very early formation, this sea has been playing an important role controlling the historical patterns of ocean water circulation, moderating the world climate, and determining the possibilities of biotic exchange of the surrounding terrestrial and marine ecosystems. The formation of a Mesozoic marine seaway between western Tethys and the eastern Pacific, across west-central Pangea, has been postulated for the Early Jurassic (Hettangian-Pliensbachian) according to biogeographic considerations, but supporting stratigraphic data are lacking. Probably since the Batlionian but certainly since the Oxfordian, the stratigraphic record indicates that this connection was fully functional and the Circum-Tropieal marine current was active. Overland dispersal between western Laurasia (North America) and western Gondwana (South America) was interrupted in the Callovian when the continents were separated by a marine gap. Later, a connecting land bridge may have been present during the latest Campanian/Maastrichtian (similar to 75-65 Ma), and since the Plio-Pleistocene (2.5-2.3 Ma). Evidence for a precursor bridge late in the Middle Miocene is currently ambiguous. Since the formation of the first volcanic archipelago within the Caribbean realm at about the Jurassic-Cretaceous transition, volcanic islands, shallow banks, and ridges have been present in the paleogeographic evolution of the area. However, these lands were generally ephemeral, and lasted just a few million years. Only after the Middle Eocene (< 40 Ma) were permanent lands present within the Caribbean realm, providing substrates for the formation and development of the present terrestrial biota.