Characteristics and Development of Wolfcampanian Rojo Caballos Detachment Slide, Pecos County, Texas
Joanne L. Pinero, Donald F. Reaser, Ralph L. Horak
Conventional theories of Permian basin tectonics may need to be modified based on our interpretation that the Rojo Caballos detachment slide of southeastern Delaware basin in Pecos County, Texas, is a large-scale submarine slide of Wolfcampanian age. A combination of events including high-angle basement faulting along the Delaware basin hinge line, juxtaposition of strata, and establishment of a basinward slope set the stage for the onset of gravity failure. The slide is 450 m thick and is composed of strata ranging in age from Mississippian through Permian. Maximum dimensions of the slide are 23 km (east to west) and 21 km (north to south). This detached mass was transported a minimum distance of 10 km westward along a bedding plane fault at the top of the Woodford Shale
The Early Permian was a time of high vertical crustal mobility. As the Central Basin platform rose and the Delaware basin subsided, the well-bedded carbonate sequence broke away, slid westward down an approximate paleoslope of 2.5° and came to rest over the site of the present Rojo Caballos field.
Initial seismic investigation of the area by Mobil Oil Corporation in the late 1950s suggested the possibility of the detachment slide. This hypothesis was contrary to "conventional" interpretations. Subsequent drilling, however, proved the detachment interpretation to be valid.
AAPG Search and Discovery Article #91043©1986 AAPG Annual Convention, Atlanta, Georgia, June 15-18, 1986.