Sequence Stratigraphic Interpretation of an Interfluve -- A Model for the Exploration of Transgressive Sheet Sands?

Brenda J. Eckles, John B. Anderson, and Peter R. Vail

The central Texas continental shelf is a vast interfluve region. Approximately 1200 kilometers of high-resolution seismic data have been collected over the area using a 15 cubic inch water gun, yielding frequencies up to 2000 Hertz. Lithologic descriptions from dozens of industry platform borings (averaging 100 meters in length), biostratigraphic data from two cores, and oxygen isotope curves from the same two cores correlated with the interpretation of the seismic data creates a sequence stratigraphic model of an interfluve. Preliminary interpretation of these seismic data and platform boring lithologic descriptions indicate no evidence of fluvial or deltaic influence on sedimentation. The dominant control on deposition is the convergence of longshore currents onto the central Texas continental shelf. The area is bounded on both sides by sandy fluvial systems. Do the converging currents import enough sand to form a transgressive sheet sand with reservoir potential? A preliminary model provides a better understanding of the influences on deposition between two major fluvial systems and whether we can expect to find significant quantities of sand preserved.

AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California