Wolfcampian Carbonate Platform Sequence Stratigraphy of the Wylie Mountains, Van Horn, TX: Implications for a Platform to Basin Wolfcamp Framework

Abstract

The Wolfcamp unconventional play in the Permian Basin is currently one of the most active drilling targets in North America. Despite this interest, the Wolfcampian strata in the Delaware Basin lack a detailed platform-to-basin sequence stratigraphic model. In recent years, access to Wolfcampian age carbonate platforms in West Texas has been restricted, though a nearly complete platform record in the Wylie Mountains near Van Horn, TX has recently become available for study. This study documents the development of the Hueco Wolfcampian carbonate platform on the western margin of the Delaware Basin and syntectonic controls on deposition during the waning stages of the Marathon-Ouachita orogeny. Eleven measured sections and two 3D drone models have been used to characterize the sequence development of the Hueco Formation using the framework established by Fitchen (1995) and Playton and Kerans (2002) in the Sierra Diablo Mountains 20 miles northwest of the study area.

The Wolfcampian Hueco Group includes the siliciclastic Pow Wow Formation at the base and 300 meters of platform interior carbonates. The Hueco Formation carbonates are comprised of three upward shallowing sequences with fossiliferous skeletal and peloidal assemblages capped by dolomitic algal laminite capped cycles. These sequences roughly correlate with the platform margin and slope deposits in the Sierra Diablo Mountains with some variability due to local structural features and variable degrees of erosion at the Wolfcamp-Leonard unconformity. The Wolfcamp-Leonard unconformity in the Wylie Mountains is marked by an influx of conglomerates and siltstones associated with a drop in sea level at the end of Wolfcampian time. This clastic pulse, as well as the Pow Wow Formation clastics at the base of the Hueco, may have clastic basinal equivalents that can be used to tie the platform sequence stratigraphy to the subsurface Wolfcamp with log and core data. Linking the Wolfcampian platforms to their basinal equivalents may assist in predicting the composition and frequency of siliciclastic and detrital carbonate influx to the basin with implications for improved reservoir quality in those intervals.

AAPG Datapages/Search and Discovery Article #90323 ©2018 AAPG Annual Convention and Exhibition, Salt Lake City, Utah, May 20-23, 2018