The Tamana Formation of the Central Range of Trinidad was studied in order to determine its importance in the stratigraphical and structural development of north‐eastern South America. Biostratigraphical, petrological and mineralogical data, combined with field mapping show that the Tamana sediments are composed of five distinct lithofacies: inner to outer shelf, burrowed shaley mudstone; outer shelf, Fe‐rich sandy limestone; submarine channel, conglomeratic mudstone; middle shelf to nearshore, algal‐foram packstone/grainstone; and intertidal to nearshore, algal‐stromatolite‐coral boundstone with coral bioherms. Maximum thickness of the Tamana Formation is 244 m. Deposition of the Tamana limestones occurred between the Praeorbulina glomerosa (latest early Miocene) and Globorotalia fohsi robusta (middle part of the middle Miocene) planktonic foraminiferal zones, and in a more continuous trend than is seen in the current outcrop belt. Detailed biostratigraphy shows that the Tamana Formation is a facies equivalent of the shallow‐ and deep‐water shales of the Brasso Formation, and the deep water turbidites of the Herrera Member of the Cipero Formation. The early diagenetic history of the Tamana limestones was dominated by the precipitation of authigenic glauconitic smectite, and the dissolution of skeletal grains and carbonate matrix. Late burial diagenesis was dominated by the precipitation of illite and illite/smectite. Comparative mineralogy and textural analyses indicate a minimum range of burial depth for the Tamana Formation at 800–1500m, with a maximum of 2400 m. Alteration of Fe‐bearing minerals to geothite and late fracturing occurred during post‐Pliocene tectonic uplift and unroofing of the Central Range. The Tamana Formation sediments can be used as a structural and stratigraphical event marker within the Late Tertiary geological history of Trinidad. These units record a phase of the tectonic interaction between the Caribbean and South American plates in the south‐eastern Caribbean, and reflect the onset of contractile deformation in the Central Range.

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Well and seismic data were combined with existing radiometric data and 1328 new laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U–Pb zircon ages from igneous, sedimentary and volcaniclastic rocks in three wells to determine the origin and evolution of key crustal terranes, and the timing of initial rifting and synrift deposition in the southeastern Gulf of Mexico and western Bahamas. These data reveal that several southeastern Gulf of Mexico crustal terranes, distinguished by their zircon age distributions and geochemistries, were amalgamated into a single terrane of mixed Pan-African and Amazonian crustal affinity (the newly named West Florida Terrane) during the formation of Pangaea. Sinistral offset along the Florida Transfer Zone (FTZ) during the Late Triassic–Middle Jurassic was likely to have been facilitated by crustal heterogeneity at the boundary between the West Florida and Suwannee terranes, a prime area for reactivation during the break-up of Pangaea. Initial extension, igneous activity and synrift deposition in the region began during the Middle Triassic in the western Bahamas and offshore North Florida, and rapidly expanded into the South Florida Basin by the Early Jurassic. Peak igneous activity and accommodation in the region was diachronous from north to south, beginning in the north during the Early Jurassic (Sinemurian–Pliensbachian) before ending in the south in the Early–Middle Jurassic (Sinemurian–Aalenian/early Bajocian). Detrital zircons in sedimentary and volcaniclastic rocks were primarily derived from local erosion of pre-existing crustal terranes. Long-distance transport was likely for pre-Neoproterozoic and post-Cambrian Paleozoic zircons. Middle Jurassic detrital zircons in volcaniclastic rocks of the western Bahamas may have been deposited during ash-fall events from hotspot activity in the southeastern Bahamas.