Basement Structure in the Northern Gulf of Mexico Province: Persistent Influence or Rejuvenated?

Michael Alexander
[email protected]

Observed positive correlations between interpreted magnetic basement structure and present-day bathymetry in the northern Gulf of Mexico province are too numerous to be coincidental. Bathymetric highs or terraces match basement highs or terraces, and bathymetric slope breaks match other significant basement structural features. These correlations pose two significant questions: has basement structure had a persistent influence on bathymetry as well on the structure and stratigraphy of the sedimentary section, or have basement structures had relatively recent movement? Answers to these questions could impact not only future exploration plays, but also the current concepts of tectonics in the Gulf of Mexico province. This paper illustrates the fit between bathymetric contour trends and basement high trends from Alaminos Canyon eastward to Walker Ridge, bathymetric contour trends and basement highs in Atwater Valley, and the seaward bathymetry bulge over basement high blocks in DeSoto Canyon. An additional correlation is that between bathymetry contours and the northern edge of an interpreted basement massif. The magnetic basement structure map also has a remarkable correlation with the shape and location of the salt canopy. The seaward edge of the salt canopy closely follows a trend of basement highs from Alaminos Canyon to Atwater Valley. The landward edge of the canopy lies along-trend, from East Breaks to Green Canyon, with the north edge of an interpreted basement massif. This paper does not provide the final answers, but is intended to provoke some unbiased thoughts about the geologic trends and history of the Gulf of Mexico geologic province.

AAPG Search and Discovery Article #90167©2013 GCAGS and GCSSEPM 63^rd Annual Convention, New Orleans, Louisiana, October 6-8, 2013