Structural and Stratigraphic Reconstruction of the Whiting Dome Salt Structure in Viosca Knoll-Mississippi Canyon, GOM, Using 3D Seismic Data

Matthew R. Worrell, Stephen F Austin State University

Abstract

Understanding the complexities of salt tectonics is one of the most important factors regarding seismic interpretation of stratigraphy, structure, and geomorphology in the Gulf of Mexico. Evaluating the processes affecting recent mobilization of salt in the shallow, well-imaged section can help provide analogues for older, similar occurrences in the deeper section, thereby providing structural models for the autochthonous salt and its effect on stratigraphy and even potential timing and migration issues of hydrocarbons.

Progradation of delta front and shelf to slope transitional sediments has expulsed and emplaced an allochthonous salt structure (Whiting Dome) in the Viosca Knoll and Mississippi Canyon protraction areas of the Gulf of Mexico. Multiple salt mobilization concepts were employed in order to more specifically define the different stages of this salt structure. In chronologic order, these include Roho (expulsion and initial emplacement), shelf- and slope-loaded salt withdrawal minibasin and detachment (early development), whole cell gravity gliding (late development), and reactive halokinesis influenced diapir creation (current).

A model was developed that describes the interplay between salt tectonics and sedimentation though time based on intensive study of the geologic history of the area, interpretation of 3D seismic data, stratigraphic mapping outboard and above the major salt structures, and conceptual restorations.