RE-EXAMINATION OF GEOPHYSICAL CONSTRAINTS ON ORIGIN AND EVOLUTION OF THE WICHITA MOUNTAINS

Research in the Wichita Mountains region of southwestern Oklahoma has long been conducted within the framework of an aulacogen: the failed arm of a plume-generated Cambrian rift. However, this framework was first suggested and developed prior to the widespread acceptance of plate tectonic theory when the terminology used was primarily descriptive. Other workers have interpreted this region as the result of transform-parallel faulting, similar to several other Appalachian-Marathon-Ouachita orogen-normal structures located throughout the southeastern North American continent. Here, we present reinterpretations of previous geophysical studies from the literature as well as new microgravity and geomagnetic data in order to place geometric constraints on the subsurface (and surface) contacts between the plutonic rocks. By better understanding these contacts, we reinterpret the “aulacogen” framework as an alternate series of potential emplacement and deformation events.