Andrew J. Pulham, 1993. "Variations in Slope Deposition, Pliocene–Pleistocene, Offshore Louisiana, Northeast Gulf of Mexico", Siliciclastic Sequence Stratigraphy: Recent Developments and Applications, Paul Weimer, Henry Posamentier
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Seismic and well-log signatures in the Pliocene-Pleistocene of the northeastern Gulf of Mexico reveal four major slope depositional units. (1) During the Pliocene, slope deposition was influenced by deformation and restructuring of moderately intact, shallowly buried, allochthonous salt sheets. Sediment supply to the slope during this period was characterized almost exclusively by repeated breakup of unstable, shelf-margin deltas. (2) Lower Pleistocene clastic sediment supply to the slope was minimal in response to a major avulsion of the Mississippi River. (3) The middle Pleistocene marked renewed slope sedimentation and was influenced by the slope fabric set up during the Pliocene. This depositional unit also marks the introduction of major erosive canyons, which are notably absent prior to this time. (4) During the late Pleistocene, slope deposition rates and eustatic amplitude and frequency increased significantly and sediment input to the slope became much less influenced by the distribution of salt. Sediment supply to the slope also became increasingly more focused by canyon development. The recently deposited upper Mississippi fan is the latest stage in this slope evolutionary process.
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Applying depositional sequence stratigraphic concepts to the interpretation of siliciclastic depositional systems is becoming an increasingly important tool in petroleum geology. After a succession of breakthroughs during the 1970s and 1980s, sequence stratigraphic concepts now have entered a phase of intense application and documentation, especially with regard to successful implementation in the field of petroleum geology. Workers have applied these concepts to a variety of databases, ranging from outcrop to cores to electric logs and to multifold seismic data. Clearly, sequence stratigraphic concepts embody–not a rigid model or template–but rather a way of looking at geology. This volume has two purposes: to compile some recent applications of siliciclastic sequence stratigraphic concepts, and to present new studies focused on refining conceptual models. This memoir grew out of a 1991 symposium, "Variations in Depositional Systems Within a Sequence Stratigraphic Framework: Applications to Exploration," organized by the authors at the AAPG annual meeting at Dallas. Robert Loucks and Rick Sarg have edited a companion volume, also published by AAPG,“Entitled Carbonate Sequence Stratigraphy: New Developments and Applications.”