Faulting in the Matador Uplift area, Texas: Revision 1, Topical report

Location, apparent vertical displacement, and latest detectable movement have been interpreted for 103 faults identified in the Matador Uplift area of Texas. The interpretations are based on lithostratigraphic correlations using geophysical logs and sample logs from 1,208 wells across 12 counties. The stratigraphic interval studied extends from crystalline basement (Precambrian) to the Alibates Formation (Upper Permian). Most of the faults strike northwest or east-northeast, have near vertical dips, and bound a series of upthrown and downthrown blocks along the east-west trending Uplift. Horizontal displacements were not determined. The maximum vertical displacement observed is nearly 4,500 ft (1,400 m), with maximum offsets on individual faults commonly in the 1,000 ft (300 m) to 2,000 ft (610 m) range. About half of the faults extend into the Lower Permian section, and at least 17 of these offset the Upper Permian Alibates Formation. The structural relief of the Matador Uplift is not as great as depositional patterns and local facies distributions. Lithologic transitions across the Uplift contribute to the uncertainty of structural interpretations. 66 refs., 33 figs., 2 tabs