Caballo Mountains gambelii" and "Callipepla squamata"), doves ("Zenaida macroura" and "Zenaida asiatica"). Common reptiles include Collared lizards ("Crotaphytus collaris"), Roundtail Horned Lizard ("Phrynosoma modestum"), Striped whipsnake ("Masticophis taeniatus"), and Western diamondback rattlesnake ("Crotalus atrox"). Caballo Mountains The Caballo Mountains, (Spanish: "horse") are a mountain range located in Sierra and Doña Ana Counties, New Mexico, United States. The range is located east of the Rio Grande and Caballo Lake, and west of the Jornada del Muerto; the south of the range extends into northwest Doña Ana County. The nearest towns are Truth or Consequences and Hatch. Most of the Caballo Mountains are located
Caballo Mountains 34.9 Ma. What is now the San Mateo Mountains (Socorro County) contained at least two cauldrons, the Nogal Canyon cauldron (28.6 Ma) and the Mount Withington cauldron (27.4 Ma). Local subsiding appears to have begun around 34.9 Ma. The Caballo Mountains began to rise in the late Oligocene, and throughout the Miocene. Approximately 9.6 Ma, the eruption of basalts near Fort Selden signaled the renewal of crustal extension and volcanism in the southern part of the rift. Activity along both older and new faults increased the number, but decreased the width of basins along this portion of the rift. The