ABSTRACT: Geologic Overview of the NE Mississippi Fan and Shelf to West Florida Terrace Region, Offshore Gulf of Mexico

BILES, NORMAN; ANDREW E. HANNAN, GEORGE A. JAMIESON, Schlumberger Reservoir Evaluation Seismic, Houston, TX; and JOHN E. BAIN, Galileo Geophysics Inc., Houston, TX

The Phase 46 16,000 line-mile 2D seismic and gravitymagnetic program was acquired, processed and interpreted from 1997-9. It consists of a 2 x 2 mile grid covering parts of Main Pass, Destin Dome, Viosca Knoll, Mississippi Canyon, Desoto Canyon, Atwater Valley, and Lloyd Ridge. Water depths range from 75 feet to over 10000 feet. Geological control from 44 biostratigraphy wells helped calibrate seven mapped horizons. In addition, a velocity cube was generated from this dataset.

A Cretaceous carbonate shelf, a prominent escarpment to the southeast, dominates the east and northeast portions of the survey. It is overlain by primarily regressive Cenozoic clastics. West of the carbonate shelf is a Miocene to Plio-Pliestocene shelf/slope/fan complex. The shelf facies is developed in the northwest and progresses through slope to deepwater fan deposits toward the southeast. This complex contains numerous allochthonous salt bodies. In general, autochthonous salt structures are present east of the detached salt, underlying the slope/fan complex. These continue eastward to the Cretaceous shelf edge.

This region is becoming an increasingly attractive area to explore. "Crazy Horse" in MC778 is a recent subsalt discovery within the survey.

BILES, NORMAN; ANDREW E. HANNAN, GEORGE A. JAMIESON, and JOHN E. BAIN

AAPG Search and Discovery Article #90908©2000 GCAGS, Houston, Texas