Partial Resolution of Several Structural and Tectonic Questions about the Greater Gulf of Mexico

Abstract:

This is an attempt to determine the solution to several questions that remain about the greater Gulf of Mexico (GGom). These questions include:
1) What is the thickness of sediments over the GGom? This has been determined, in general, by inverting for depth to basement using spectral methods and gravity and magnetic data (Odegard, 2011). The sediment thickness is considerably thicker in the central Gulf than that given by the Crust1.0 model possibly reaching as much as 20+ kilometers (66,000 feet) versus 15 kilometers.
2) Where is oceanic crust in the GoM? This was partially answered by Odegard (2005) however the location beneath Salt and thus its extension was not clearly determined. Using the results of 1) this problem can be resolved. Almost certainly little or no "pure" oceanic crust exists due to the opening of the GoM. However proto-oceanic or transitional crust exists in its place.
3) Do "transfer zones" exist in the GGoM? In the past several significant transfer zones related to the opening of the GoM have been postulated. Gravity and magnetic data integrated with the geology do not show the existence of most of these zones. However several are required due to the opening of the GoM and to the opening of the North Atlantic.
4) Was there a hot spot or mantle plume in the GoM as postulated by Bird, et al. (2005)? There appears to be no clear evidence in the gravity or magnetic data over the GoM for a hot spot trace. The amplitudes of the magnetic anomalies are very small unlike well-known hot spot traces. This may be due, however, to the depth of basement shown in 1) approaching the Curie depth. However, the basement structure from 1) appears to show one or two large seamounts in the center of the GoM but no track of large seamounts in the postulated direction.
These data and interpretations are based on an integrated GIS project combining a large number of different data types. The above questions will be discussed as well as others related to the basin developement of Latin America, the Caribbean and the greater Gulf of Mexico.