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Detailed stratigraphic and facies analyses were conducted and combined with seismic facies and 3D seismic‐derived plan view images to interpret the depositional environments, processes and depositional elements during the Miocene for an area located in the southern Gulf of Mexico. The results showed that deposition during the Miocene mainly occurred in a slope setting, with bathymetric changes associated with highs and mini‐basins related to salt features. From the sedimentological interpretation, 13 sedimentary facies were identified. The abundant lithofacies were structureless (massive) sandstone and massive mudstone. Ripple‐ , parallel and cross‐laminated sandstone and siltstone were found in minor proportions. The main depositional processes were related to turbidity currents, including high‐density and low‐density currents; debris flows (mud flows and grain flows) were of secondary importance, as was deposition from fallout of suspended hemipelagic mud particles. The vertical and lateral distributions of facies revealed seven facies associations linked to depositional environments. These facies associations were the building blocks that were used to characterize the depositional elements recognized on seismic data. The main depositional elements identified were mass‐transport complexes, submarine channels, and frontal splays. Finally, interpretations from different data sets enabled the conclusion that, during the Miocene in this area were submarine fans deposited on an irregular paleotopography, with topographic lows and highs controlled by salt tectonics. [ABSTRACT FROM AUTHOR]

Neogene shelf, slope, canyon, and slope-to-basin-floor transition plays in the southern Laguna Madre-Tuxpan (LM-T) continental shelf reflect a variety of structural and stratigraphic controls, including gravity sliding and extension, compression, salt evacuation, and lowstand canyon and fan systems. The Neogene in the LM-T area was deposited along narrow shelves associated with a tectonically active coast affected by significant uplift and erosion of carbonate and volcanic terrains. This study characterizes 4 structurally defined trends and 32 Neogene plays in a more than 50,000-km² (19,300-mi²) area linking the Veracruz and Burgos basins. The Cañonero trend in the southern part of the LM-T area contains deep-seated basement faults caused by Laramide compression. Many of these faults are directly linked to the interpreted Mesozoic source rocks, providing potential pathways for vertically migrating hydrocarbons. In contrast, the Lankahuasa trend, north of the Cañonero trend, contains listric faults, which detach into a shallow horizon. This trend is associated with thick Pliocene shelf depocenters. The dominant plays in the Faja de Oro-Náyade trend in the central part of the LM-T area contain thick lower and middle Miocene successions of steeply dipping slope deposits, reflecting significant uplift and erosion of the carbonate Tuxpan platform. These slope plays consist of narrow channel-fill and levee sandstones encased in siltstones and mudstones. Plays in the north end of the LM-T area, in the southern part of the Burgos basin, contain intensely deformed strata linked to salt and shale diapirism. Outer-shelf, slope, and proximal basin-floor plays in the Lamprea trend are internally complex and contain muddy debris-flow and slump deposits. Risk factors and the relative importance of play elements vary greatly among LM-T plays. Reservoir quality is a critical limiting play element in many plays, especially those in the Cañonero. [ABSTRACT FROM AUTHOR]