Discovery of Ring Faults Associated with Salt Withdrawal Basins of Early Cretaceous Age in the East Texas Basin
S. J. Maione
Scott Pickford, A Core Laboratories Company, Houston, TX
Salt withdrawal basins in the East Texas Basin developed during the Early Cretaceous in response to salt movement and dissolution processes affecting the Jurassic Louann salt. These basins are characterized by an expanded section of Lower Cretaceous marine and deltaic sedimentary rocks. Recognition of fault sets associated with the evolution of these basins has gone undetected until the recent Coherence CubeTM processing of a non-proprietary 3-D seismic survey conducted by Schlumberger in the La Rue dome–Fairway Field area, Henderson County, Texas. Coherence Cube images aptly exhibit extraordinary sets of concentric ring faults that comprise the periphery of two salt withdrawal basins. The 370 MMbbl Fairway oil field is located at the junction of these two sets of ring faults.
The symmetry of the La Rue salt withdrawal basin allows salt budget calculations that indicate of the approximate 55 mi3 of Louann salt that transited the La Rue diapir system, about 10 mi3 is preserved within the salt dome, and about 45 mi3 was lost to dissolution at the sea floor during the Early Cretaceous.
The structural style of the high-angle ring faults creates a multitude of possible fault traps in a previously unattractive structural setting. Early Cretaceous age of the ring faults establishes that these faults are a significant element in evaluating petroleum migration patterns and traps in the basin. The discovery of Early Cretaceous ring faults in the East Texas Basin brings new perspectives to development and exploration drilling in this mature petroleum province.
AAPG Search and Discovery Article #90905©2001 AAPG Southwest Section Meeting, Dallas, Texas