ABSTRACT

Newly constructed bathymetric maps (TAMU) and recent multibeam swath mapping surveys by NOAA of the continental slope of the northwestern Gulf of Mexico reveal the presence of over 90 intraslope basins with relief in excess of 150 meters. Bathymetry in conjunction with multichannel seismic data is extremely valuable for studying the halokinetic style of the slope. The evolution and the general configuration of the basins on the continental slope off Texas and Louisiana are a function of halokinesis of allocthonous salt.

Intraslope-interlobal and intraslope-supralobal basins occupy the upper and lower continental slope respectively. The intraslope-interlobal basins of the upper continental slope are commonly elongate in shape with a north to south and northwest to southeast orientation. These basins are located in areas where salt is more deeply rooted than in the lower slope. The intraslope-supralobal basins of the lower slope have a more circular geometry and are located in the Sigsbee Salt Nappe complex, the Sigsbee Escarpment being the southern boundary of the nappe.