Sequence Stratigraphic Evolution of the Thunder Horse Mini-Basin, Mississippi Canyon, Northern Deep Gulf of Mexico

Todd Lapinski, Paul Weimer, and Renaud Bouroullec
University of Colorado, Boulder, CO

This study documents the stratigraphic evolution of the Thunder Horse mini-basin, in the southern Mississippi Canyon, northern deep Gulf of Mexico. Analysis is based on the integration of a 378 square mile 3 dimensional seismic data set, several wireline logs, and biostatigraphic data.

The stratigraphic evolution is divided into nine intervals deposited between 99 to 9.0 Ma. From 99 to 24 Ma, the lithologies in the Thunder Horse mini-basin are interpreted as dominantly deepwater marls with interbedded shales. The interval reflects little siliciclastic input into the area. From 24 to 14.35 Ma, a major input of deepwater siliciclastic sediments began because sands are deposited in amalgamated channel-fills and amalgamated sheets within major paleobathymetric lows, and shales were deposited across paleobathymetric highs. From 14.35 to 13.05 Ma, a large mass transport complex was deposited to the south and is overlain by channel-fill and overbank sediments. From 13.05 to 9.0 Ma, the lithologies throughout the area are dominantly overbank shales with thin channel-fill sands, suggesting that major sand was bypassed through the area and farther downslope to the south.

The main reservoir sands at the Thunder Horse and Thunder Horse North discoveries occur between 15.3 to 14.35 Ma. The sands were deposited within a paleobathymetric low in a mixture of amalgamated channel-fill sands and possible amalgamated sheet sands.

AAPG Search and Discovery Article #90032©2004 GCAGS 54th Annual Convention, San Antonio, Texas, October 10-12, 2004