Pisgah Crater

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Pisgah Crater, also Pisgah Volcano, is a young volcanic cinder cone located in the Mojave Desert east of the California city of Barstow on the National Old Trails Highway. It can be found at 34°44′47″N, 116°22′30″W.

Pisgah Volcano is the youngest vent in the Lavic Lake volcanic field. There may have been activity at this site as recent as 2,000 years ago, though more likely 20,000 to 50,000 years ago. It is too young for the commonly used potassium-argon dating technique (usable on specimens over 100,000 years old), and no charred organic material for radiocarbon dating has been found. However, lava at nearby (and similarly active) Amboy Crater is interbedded with Bristol Playa sediments at a depth of about 9 meters (30 feet); these sediments are approximately 100,000 years old. Recent argon-argon dating reveals an age of approximately 18,000 years ± 5,000 years (~90% certainty) for the most recent flow (Sylvester et al., 2002, Bulletin of the Seismological Society of America, v. 92, p. 1333-1340).

Lava flows extend 18 km (11 miles) to the west and 8 km (5 miles) to southeast of the cone, containing basalt primarily of the pahoehoe texture, with some a'a. The flows contain numerous lava tubes and caves.

Currently, the crater stands 98 meters (321 feet) off the surrounding High Desert terrain, and has a base diameter of 488 meters (1,600 feet). It has lost much of its original cinder cone shape to ongoing aggregate mining operations, in addition to minor natural erosion.

The crater and much of the surrounding lava field are located on private property. Despite this, the lava tubes in the area are a somewhat popular and easily accessible destination for caving.