Abstract: Salt Movement on Continental Slope, Northern Gulf of Mexico

C. C. Humphris, Jr.

Regional sparker lines across the continental slope of the northern Gulf of Mexico, surveyed by Chevron, Exxon, Gulf, and Mobil, demonstrate the close relation between salt movement and sediment deposition.

Salt features on the outer slope have not developed to the extent of those near the shelf, because sedimentation has been much less on the slope. In the eastern part of the gulf, salt structures are more mature than domes in the western gulf area as a result of a greater amount of sedimentation. The youngest salt features, on the outer slope, are much larger areally than domes on the shelf.

Seismic data from the outer slope, where only several thousand feet of overburden is present, suggest that salt-dome growth in this area has been initiated by lateral southward flowage of salt caused by sediment loading updip. The Sigsbee scarp appears to be a salt scarp formed by this gulfward salt flowage. The bulge of the Sigsbee scarp opposite the Pleistocene depocenter suggests that much of this lateral salt flowage occurred during Pleistocene time. The presence of salt structures on the northern Gulf of Mexico outer continental slope does not indicate the original area of salt deposition. The present Red Sea serves as a model for the Gulf of Mexico at the time of Mesozoic breakup.

AAPG Search and Discovery Article #90972©1976 AAPG-SEPM Annual Convention and Exhibition, New Orleans, LA