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Kilbourne hole

Kilbourne hole is a Maar volcanic crater, located 30 miles west of the Franklin mountains of El Paso, Texas, in Dona Ana County, New Mexico. The hole is a rare example of volcanic action without a mountainous rim. The theory of formation is that a volcanic eruption occurs in the presence of ground waters, beneath the surface of the earth. As the hot lava and magma encounter the waters, a huge bubble of steam is produced, which blows out a large crater; thus, it is not necessary for the lava and magma to build up a mountainous deposit. The crater is thought to be 80,000 years old.

The volcanic features around El Paso and vicinity are part of the Rio Grande Rift, which extends northward into Wyoming.

Description of the crater

Basalt cliffs of Kilbourne hole,
looking north from south lip of crater

The hole is over a mile wide, and over 300 feet deep. Two basalt cliffs inside the crater, with the characteristic reddish purple hexagonal columns occupy the northeast and southeast sides of the crater. The cliffs are about 40 feet high. Layers of ashfall and crumbling sediment also rise about 40 feet high, on the south rim of the crater. This ashfall section will not support your weight, on the south rim; it is safer to stay on the basalt cliffs and the sand dunes. Sand dunes have collected on the east side of the crater, rising about 100 feet above the desert floor. A dry lakebed lies on the floor of the crater.

The basalt cliffs resemble the cliffs of the Devils Postpile National Monument near Yosemite National Park, except that they are not as tall.

Rockhounds can pick up Green Olivine stones, which are available at only about 5 places on earth, such as by the Red Sea, and in Arizona.

Lava chunks exist in abundance. The basalt column fragments are each larger than a person.

Hunt's hole lies several miles just south of Kilbourne hole.

Apollo astronauts trained in these craters in the 1970s.

Directions to Kilbourne and Hunt's holes

Because there is new road-building at the southern end of Dona Ana county, the existing published descriptions are out of date. Compiled here is a description gained by interviewing local residents who gave accurate directions, from their own experience: Use caution. You will be completely isolated here. Cell phones are out of range here. Take several liters of water per person. Wear a hat. Tell others of your plans, and give an estimated time of return.

To get back to El Paso or Las Cruces, reverse the directions. The cell phones will start working at the sand bluffs next to the Rio Grande.