A geologic overview of the Wild Rivers Recreation Area, New Mexico
— Edward L. Heffern

The U.S. Bureau of Land Management's (BLM) Wild Rivers Recreation Area sits at the junction of the Rio Grande and Red River in north-central New Mexico. The 26-million-year history of the Rio Grande rift serves as a framework to discuss, in general terms, the rocks and landforms which are exposed in the Recreation Area and vicinity. Early Miocene rift-related rhyolitic volcanism was a precursor to uplift of the Sangre de Cristo Mountains and deposition of Santa Fe Group sediments in the subsiding rift basin. Pliocene volcanism of the Taos plateau, including the Servilleta Basalt flows, and dacite and andesite cones, followed. More recently, the Rio Grande and Red River have cut down through the Taos Plateau to form gorges. This paper concludes with a short overview of the proposed Molycorp, Inc. mill-tailings pond on Guadalupe Mountain and related ground-water and management issues.