Volcanic pipe Volcanic pipe Volcanic pipes are subterranean geological structures formed by the violent, supersonic eruption of deep-origin volcanoes. They are considered to be a type of "diatreme". Volcanic pipes are composed of a deep, narrow cone of solidified magma (described as "carrot-shaped"), and are usually largely composed of one of two characteristic rock types — kimberlite or lamproite. These rocks reflect the composition of the volcanoes' deep magma sources, where the Earth is rich in magnesium. Volcanic pipes are relatively rare. They are well known as the primary source of diamonds, and are mined for this purpose. Volcanic pipes form as
Coso Rock Art District Coso Rock Art District Coso Rock Art District, containing the Big and Little Petroglyph Canyons, is a rock art site containing over 100,000 Paleo-Indian and/or Native American Petroglyphs. The Coso Range is between the Sierra Nevada and the Argus Range. Indian Wells Valley lies to the south of this location. This north-south trending range of about consists of rhyolitic domes and outcrops of volcanic rock. Also known as Little Petroglyph Canyon and Sand Tanks, Renegade Canyon is but one of several major canyons in the Coso Range, each hosting thousands of petroglyphs (other locations include Haiwee Springs, Dead End Canyon,