Late Quaternary Facies and Structure, Northern Gulf of Mexico

Abstract

Abstract This book illustrates the use of high-resolution remote sensing techniques to (1) determine the depositional environments of late Quaternary sediments on the continental shelf and upper continental slope, northern Gulf of Mexico, (2) identify and map specific depositional sequences and facies, (3) demonstrate the morphology of depositional and structural features, (4) identify the erosional unconformities or stratigraphic time gaps separating primary depositional sequences, (5) identify the principal processes involved in dispersing sediments across the shelf margin into deeper water, and (6) document the extent and chronology of post-depositional deformation. The book is intended to demonstrate (1) how sea level fluctuation, sediment loading, and diapir- ism have interacted to build and modify structurally the outer shelf margin through time, and (2) how late Quaternary sea level history is revealed by the stratigraphy of depositional units. The continental shelf and upper continental slope in the northern Gulf of Mexico are ideal for studying and contrasting the sedimentary suites deposited during the cyclic episodes of late Quaternary sea level rise and fall. As recipient of three-fifths of the drainage of the United States, the Gulf of Mexico is characterized by high rates of sediment accumulation that during the Pleistocene aggregated some 4,000 m (13,000 ft) on the outer shelf off southwestern Louisiana (Woodbury et al., 1973). Because of the continually high rate of sediment influx, features of erosion and deposition are more likely to be preserved along the shelf in the northern Gulf of Mexico than on shelves with lower sedimentation rates. Also