SOCIETAL IMPACT OF EVAPORITE KARST IN THE LOWER PECOS REGION, SOUTHEASTERN NEW MEXICO AND WEST TEXAS, USA

Evaporite-karst phenomena in the lower Pecos region span over three degrees of latitude, extending for more than 400 kilometers from Santa Rosa, NM in the north to the state line south of Carlsbad, and beyond into west Texas. The presence throughout the Permian section of soluble gypsum and halite bedrock in outcrop or in the subsurface has resulted in manifestations of karst processes at a variety of scales, from small sinkholes and caves to regional subsidence basins, and has significantly influenced the topography along the margins of the Pecos River valley. Anthropogenic processes, such as solution mining, road construction, and improperly cased or plugged oil and water wells, have accelerated and modified the ongoing natural evolution of the evaporite karst landscape. The Guadalupe Mountains region of southeastern New Mexico and west Texas is world-famous for its caves formed in carbonate bedrock. However, with a few exceptions, most limestone caves in the Guadalupe Mountains are located above the regional water table and apart from tourism have little direct impact on societal infrastructure. Evaporite karst features and processes, by contrast, have had a profound influence on the geomorphology, hydrology, economy and infrastructure of the lower Pecos region.