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This study focuses on the interpretation of stratigraphic sequences through the integration of biostratigraphic, well log and 3D seismic data. Sequence analysis is used to identify significant surfaces, systems tracts, and sequences for the Miocene succession. The depositional systems in this area are dominantly represented by submarine fans deposited on the slope and the basin floor. The main depositional elements that characterize these depositional settings are channel systems (channel-fills, channel-levee systems), frontal splays, frontal splay complexes, lobes of debrites and mass-transport complexes. Five genetic sequences were identified and eleven stratigraphic surfaces interpreted and correlated through the study area. The Oligocene-lower Miocene, lower Miocene and middle Miocene sequences were deposited in bathyal water depths, whereas the upper Miocene sequences (Tortonian and Messinian) were deposited in bathyal and outer neritic water depths. The bulk of the Miocene succession, from the older to younger deposits consists of mass-transport deposits (Oligocene-lower Miocene); mass transport deposits and turbidite deposits (lower Miocene); debrite deposits and turbidite deposits (middle Miocene); and debrite deposits, turbidite deposits and pelagic and hemipelagic sediments (upper Miocene). Cycles of sedimentation are delineated by regionally extensive maximum flooding surfaces within condensed sections of hemipelagic mudstone which represent starved basin floors. These condensed sections are markers for regional correlation, and the maximum flooding surfaces, which they include, are the key surfaces for the construction of the Miocene stratigraphic framework. The falling-stage system tract forms the bulk of the Miocene sequences. Individual sequence geometry and thickness were controlled largely by salt evacuation and large-scale sedimentation patterns. For the upper Miocene, the older sequence (Tortonian) includes sandy deposits, whereas the overlying younger sequence (Messinian) includes sandy facies at the base and muddy facies at the top; this trend reflects the change from slope to shelf settings. [ABSTRACT FROM AUTHOR]

Abstract In the southern Gulf of Mexico, deepwater sediments were affected during deposition by contractional and extensional deformation events and halokinesis. The Miocene reservoirs in this area were deposited in slope and basinal settings during the falling-stage systems tracts and the lowstand systems tracts, where channel and frontal splay depositional elements were the most important. The integration of the structural analysis with seismic data, seismic attributes and isochron maps allows us to evaluate how the deformational events (especially the contractional event D3) controlled the distribution of sediments and the external geometry of their deposits. This interplay between deformation and sedimentation mainly occurred in two ways. First, the structural elements modified the paleobathymetry of the basin and created an accommodation space for clastic deposition. Second, the structural features controlled the entry of sediments. During the Oligocene and early Miocene, the depocenters were bounded by diapirs, salt sheets and structural highs formed by older salt anticlines. On the other hand, for the middle Miocene, the depocenters were controlled by the presence of folds in the southern part of the study area and by shortened diapirs and salt sheets in the periphery. The formation of these depocenters provided the accommodation space for sediment deposition; as a result, during the early and middle Miocene, the frontal splays were confined to these depocenters. At the end of the middle Miocene, these depocenters were filled, and channel levee systems and frontal splay complexes predominated. Finally, during the late Miocene, the depocenters formation was controlled by the extensional event, which provided the accommodation space for sediment deposition in half-grabens, where frontal splays complexes and channel levee systems were the most important depositional elements. All of these structural elements had significant implications for the architecture and internal organization of the turbidite systems. Highlights • Reservoirs were deposited in the slope during the falling-stage and lowstand systems tracts. • Structural elements modified the paleotopography of the basin creating accommodation space. • Structural elements controlled the entry of sediments. • Deformation events had implications in the architecture and organization of turbidites. [ABSTRACT FROM AUTHOR]