Abstract
This paper focuses on the analyses of the clastic sedimentary infill of the Coastal Plain of Eastern Mexico, which initiated synchronously with the Laramide orogeny in the vicinity of the Golden Lane. Results of these analyses are used as boundary conditions for calibrating/interpreting seismic profiles across more distal depocenters in the offshore of the Gulf of Mexico, from the sea shore and continental slope in the west to the abyssal plain in the east. The objective of the study is to better predict the reservoir distribution in the Deep offshore Basin of the Gulf of Mexico (DBGM), in order to explore for petroleum. The Coastal Plain is underlain by three morpho-tectonic domains: the tectonic front of the Sierra Madre Orientale (SMO), the Chicontepec deep water flexural basin, and the Tuxpan Platform (also known as the Golden Lane). Each domain is characterized by a distinct, dominantly siliciclastic Cenozoic lithostratigraphy. After a Jurassic rifting episode, followed by thermal subsidence, the oceanic basin and its western passive margin were deformed during the Upper Cretaceous and Paleogene, by far field stresses associated with the Cordilleran-Laramide Orogeny. Starting in the Late Cretaceous-Early Paleogene and during the Early Eocene, the tectonic load associated with the Laramide Orogen (Sierra Madre Oriental, SMO) caused flexural subsidence of the foreland located under the Coastal Plain. During this period, a massive transfer of siliciclastic sediments occurred from the Laramide foothills into the adjacent foreland. Sediments were eroded of the Sierra Madre tectonic wedge. Loading by these sediments pushed source units associated with the former passive margin down ward. The first syn-tectonic sediments of the Laramide orogeny were turbiditic silt layers in submarine fans which record also numerous collapse episodes and gravity slides. During the Late Eocene and Oligocene, the flexural subsidence stopped in the hinterland, whereas the subsidence of the passive margin resumed. This resulted in a change in the overall sedimentary architecture of the basin. Paleo-highs and reefs facies of the Golden Lane were flooded. Clastics by-passed the reefs and progradational clastic stratification formed as sediment moved towards the DBGM in the east. The final depositional environment of the continental platform/Coastal Plain became deltaic, marked by a succession of sand bars, levees and channels systems. From Miocene times onward, a system of gravitational listric faults developed near the platform to slope transition, resulting in a coeval compressional system at the transition between the slope and the abyssal plain. This system is driven by sediments charge. Because the sedimentation rate is larger than the subsidence, a large amount of clastics and slumped sediments are deposited in hangingwall basins.