Plate Tectonics and the Ouachita System in Texas, Oklahoma, and Arkansas
The Ouachita system is commonly considered to be an extension of the Appalachian orogen into the area of Arkansas, Oklahoma, and Texas. Although the Appalachians have been interpreted within the framework of plate tectonics, most analyses of the Ouachita system have relied primarily on classical geosynclinal theory. Here, we apply a cordilleran-type model (Dewey and Bird, 1970) to the Ouachita system. This model appears consistent with the stratigraphic and structural development of the system, with the chronologic development of the Atlantic Ocean, and with proposed plate tectonic models for the Appalachians. Also, it is consistent with limited geophysical evidence, which includes a gravity profile across a portion of Texas. The cordilleran-type model proposed here implies Paleozoic and possible Mesozoic spreading centers in the region of the Gulf of Mexico.