THE MUENSTER UPLIFT OF NORTH TEXAS

The Fort Worth Basin (FWB) in North Texas is a major Paleozoic sedimentary basin which has been the focus of extensive oil and gas exploration in recent years. This sedimentary basin is flanked to the northeast by a prominent structural feature characterized by a set of NW-SE trending reverse faults which extend from the Wichita Uplift in southwestern Oklahoma to the buried Ouachita folded thrust belt in northeast Texas. The structure which is strongly asymmetric, represents greater than 5000’ of offset to the downthrown southwest side of the FWB. It is a basement-cored uplift, similar in style to Laramide structures of Colorado and Wyoming. During Cambrian time, southern Oklahoma experienced rifting associated with formation of the Southern Oklahoma Aulacogen. Subsidence occurred in Late Cambrian to Early Devonian and continued into the Mississippian depositing thick accumulations of marine limestones, sandstones and shales in the adjacent FWB. Later Pennsylvanian compression caused folding and high-angle reverse and transpressional faulting in the vicinity of the Wichita and Arbuckle uplifts, along with development of low-angle thrusts and nappes farther east in the Ouachitas. Subsidence of the Muenster high occurred in Late Pennsylvanian time as the region received sediments shed from uplifts to the NW, NE, and perhaps S. The uplift is commonly but erroneously referred to as the “Muenster Arch” but it has none of the gentle or symmetrical structural definition of an arch. For this reason, I refer to it as the Muenster Uplift or Muenster structure. Few studies have examined the geologic history of the Muenster structure. A structural interpretation of the faults was carried out using seismic, well, gravity and magnetics to better understand the significance of the Muenster Uplift for the Late Paleozoic tectonic evolution of north-central Texas.