Kilbourne Hole


Kilbourne Hole is a maar volcanic crater, located west of the Franklin Mountains of El Paso, Texas, in the Potrillo volcanic field of Doña Ana County, New Mexico. Another maar, Hunt's Hole, lies just two miles south of Kilbourne Hole. These holes are rare examples of volcanic action without a mountainous rim.
The theory of maar formation is that rising magma super-heats water-saturated earth, far enough below the surface that a high pressure can be contained. At some point, the pressure is too much, and a steam explosion occurs, throwing the earth out in a catastrophic event. Country rocks are fragmented and expelled in the atmosphere, eventually creating a deep crater, the bottom of which sits below the pre-eruptive ground surface.
Estimates of the age of the crater vary from about 24,000 to about 80,000 years.
The volcanic features around El Paso and vicinity are part of the Potrillo volcanic field, in the Rio Grande rift, which extends northward into Colorado.
In 1975, Kilbourne Hole was designated as a National Natural Landmark by the National Park Service.

Description of the crater

The crater is at an elevation of. It has a diameter of by and a depth of.
The hole is over a mile wide, and over deep, with crumbling basalt cliffs all around except at the southwest corner. The basalt cliffs resemble the cliffs of the Devils Postpile National Monument near Yosemite National Park, with the characteristic reddish purple hexagonal columns, except that they are not as tall. The cliffs are about high. Lava chunks exist in abundance.
Hunt's Hole is a little smaller, with basalt cliffs only at the northeast and southeast sides of the crater. Layers of ashfall and crumbling sediment also rise about high, on the south rim of the crater. Sand dunes have collected on the east sides of the both craters, rising about above the desert floor. A dry lakebed lies on the floor of each crater.

NASA training

geologically trained the Apollo Astronauts in April and Nov. 1969, June 1970, and Jan. and Dec. 1971. Astronauts who would use this training on the Moon included Apollo 12's Pete Conrad and Alan Bean, Apollo 14's Alan Shepard and Edgar Mitchell, Apollo 15's David Scott and James Irwin, Apollo 16's John Young and Charlie Duke, and Apollo 17's Gene Cernan and Jack Schmitt.

Access

Kilbourne Hole is in BLM land and is available as an unimproved recreational area. It is accessed via Doña Ana County Road A-011, driving 8 miles west from the railroad. The hole is "on the right, past the big tan dirt bank." Much of the land inside the hole is private property. Hunt's Hole is about 2 miles south on A-013.