The Caballo Mountains, 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.
The Abiquiu Formation is a geologic formation found in northern New Mexico. Radiometric dating constrains its age to between 18 million and 27 million years, corresponding to the late Oligocene to Miocene epochs.
The Gila Group is a group of geologic formations found along the upper tributaries of the Gila River in Arizona and New Mexico. Radiometric dating of lava flows within the group yields an age of Miocene to Quaternary.
The Tesuque Formation is a geologic formation in north-central New Mexico, United States. The formation provides an unusually complete record of the evolution of mammals during the Miocene epoch.
The Zia Formation is a geologic formation in the southwestern Jemez Mountains and northwestern Santo Domingo basin. It contains vertebrate fossils that date it to early to middle Miocene in age.
The Galisteo Formation is a geologic formation in New Mexico. It contains fossils characteristic of the Bartonian stage of the Eocene epoch, Duchesnean in the NALMA classification.
The Palm Park Formation is a geologic formation in southern New Mexico. It preserves fossils dating back to the Eocene epoch.
The Salitral Formation is a Late Triassic geologic formation found in north-central New Mexico, primarily the northwestern Jemez Mountains. It is an older subunit of the Chinle Group, overlying the Shinarump Conglomerate and underlying the Poleo Formation.
The Espinaso Formation is a geologic formation in New Mexico. It has a radiometric age of 34.6 to 26.9 million years, corresponding to the late Eocene through Oligocene epochs.
The Santa Fe Group is a group of geologic formations in New Mexico and Colorado. It contains fossils characteristic of the Oligocene through Pleistocene epochs. The group consists of basin-filling sedimentary and volcanic rocks of the Rio Grande rift, and contains important regional aquifers.
The El Rito Formation is a geologic formation in New Mexico dating to the Eocene epoch. It records a time when sediments were trapped in deep basins in western North America rather than being carried downstream to the Gulf of Mexico, so that sediments of this age in the western Gulf are mostly from the Appalachian Mountains.
The Ritito Conglomerate is a geologic formation in northern New Mexico dating to the Oligocene epoch.
The Gilman Conglomerate is a geologic formation in northern New Mexico dating to the Oligocene epoch.
The Arroyo Ojito Formation is a late Miocene geologic formation exposed near Albuquerque, New Mexico. It records deposition of sediments in the Albuquerque Basin of the Rio Grande Rift after full integration of the Rio Grande through the basin.
The Tuerto Formation is a geologic formation exposed around the Ortiz Mountains of New Mexico. It is estimated to be of Pliocene to Pleistocene age, and forms the gravel cap of the Ortiz surface, one of the first pediment surfaces recognized by geologists.
The Blackshare Formation is a geologic formation exposed in the Hagan Basin west of the Ortiz Mountains of New Mexico. It is estimated be to of Miocene age.
The Cerro Conejo Formation is a middle to late Miocene geologic formation exposed near Albuquerque, New Mexico.
The Ceja Formation is a Pliocene to Pleistocene geologic formation exposed near Albuquerque, New Mexico.
The Hayner Ranch Formation is a geologic formation found near the San Diego Mountains of New Mexico. It is estimated to have been deposited during the Miocene epoch.
The Oligocene Chuska Sandstone is a geologic formation that crops out in the Chuska Mountains of northeastern Arizona and northwestern New Mexico. The formation is a remnant of a great sand sea, or erg, that once covered an area of 140,000 square kilometres (54,000 sq mi) reaching from the present locations of the Chuska Mountains to near Albuquerque and to the southwest. This erg deposited a succession of sandstone beds exceeded in thickness only by the Navajo Sandstone on the Colorado Plateau.
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