The Exploration Potential of the Downdip Yegua in South Texas

CUMMINS, G. D., B. E. WINKELMAN, and R. N. ROSEN, ARCO Oil & Gas, Houston, TX

Historically, south Texas has been known for the Wilcox, Vicksburg, and Frio trends, which continue to be highly productive. However, there is a 25-mi area between the Wilcox and Vicksburg producing trends, south of the San Marcos arch, in which few wells have penetrated depths below 7000 ft. This lightly explored area could contain an expanded Yegua interval that has not previously been identified. The integration of seismic stratigraphy, high-resolution biostratigraphy, seismic amplitude analysis, and well-log analysis make it possible to explore for these downdip Yegua opportunities by reinterpreting available well data. Models have been used to delineate the shelf margins for the upper and lower Yegua intervals, identifying potential reservoirs in expanded proximal lowstand wedge nd lowstand fan deposits south and east of areas currently being explored.

AAPG Search and Discovery Article #91006 © 1991 GCAGS and GC-SEPM Meeting, Houston, Texas, October 16-18, 1991 (2009)