STRAUB, ARTHUR W., Colorado School of Mines, Geology Department, Golden, CO

ABSTRACT: Subsea Channel in the Bossier Shale, East Texas

Using dipmeter data, well logs, and a 30-foot core section, a reservoir description of a tight gas sandstone within the Bossier Shale (Jurassic-Upper Cretaceous) east Texas indicates it is part of a deep-water sinuous, channel enclosed in marine shale containing a potential hydrocarbon yield.

Wells within the Bossier Shale provide dipmeter data revealing microstructure representing regional and local bedding orientation. Borehole breakout information at varied depths reveals the present-day field stress. Approximately thirty well logs from the field are correlated to construct stratigraphic cross sections, isopach maps, net-sand maps, and a structure map to the top of the encased Bossier sandstone.

This project attempts to demonstrate the existence of a subsea channel represented by a sandstone body encased in a thick sequence of marine shale. Previous work focused on present-day deep-sea channels and a few fossil channels inferred by their relative position in well logs and microfossils in drilled core samples. The use of dipmeter data in such a study is rare or absent in the literature. Dipmeter data may describe dipping bed sets in a subsea meander bend in a Jurassic-aged continental margin setting. Reservoir characterization by means of this data and well log cross sections should help define field compartmentalization.

AAPG Search and Discovery Article #90909©2000 AAPG Foundation Grants-in-Aid