Abstract: 3-D Basin Analysis Reveals Early Gulf of Mexico Origin

Jack G. Elam, Stewart Chuber

A proper display of the earth's curvature reveals that the rifted Gulf of Mexico basin was created over a mantle plume that evidenced several major uplifting cycles. The salt of the first two episodes was deposited in a central crestal graben and on the surrounding tilted fault blocks. New oceanic crust was emplaced during its final thermal culmination, which is late Middle Jurassic (Callovian) in age. This heating and dilational fracturing sequence created an ideal set of conditions for maturing and preserving hydrocarbons.

"The Gulf of Mexico Basin", volume J of the DNAG series, edited by Amos Salvador, provides the data used in this analysis. The earth's curvature has been enlarged on the cross sections to match the 10-fold vertical exaggeration to display a salt and crust distribution resulting from three stages of dilational thermal rifting. The earliest salt deposition was in the East Texas, North Louisiana, Mississippi, and De Soto Canyon areas. The second stage salt occurs in the Rio Grande embayment, Houston embayment, and South Louisiana shelf areas. Salts of both ages were deposited within the collapsed crestal graben of the thermal dome, the present site of the thickest salt deposits on the Texas Louisiana slope. The final uplift created vertically intruded new oceanic crust, and normal oceanic waters from the Atlantic ocean entered the basin, ending the hypersaline conditions.

AAPG Search and Discovery Article #90955©1995 GCAGS 45th Annual Meeting and Gulf Section SEPM, Baton Rouge, Louisiana