Bishop Tuff
Encyclopedia
The Bishop Tuff is a welded tuff that formed 767100 ± 900 years ago as a rhyolitic
pyroclastic flow
during the eruption that created the Long Valley Caldera
. Large outcrops of the tuff are located in Inyo
and Mono Counties
, California
, United States
.
. The tableland formation is located east of U.S. Route 395
and west of the Nevada
stateline, sitting northwest of Bishop
and southeast of Crowley Lake
and Mammoth Lakes
. Another part of the flow is south of Mono Lake
, and surrounding the Mono-Inyo Craters
.
Deposits of Bishop Tuff in this area cover nearly 2200 square kilometre, and range in thickness from 150 metres (492.1 ft) to 200 metres (656.2 ft).
The Owens River
cut through the volcanic plateau
, creating the Owens River Gorge
.
Rhyolite
This page is about a volcanic rock. For the ghost town see Rhyolite, Nevada, and for the satellite system, see Rhyolite/Aquacade.Rhyolite is an igneous, volcanic rock, of felsic composition . It may have any texture from glassy to aphanitic to porphyritic...
pyroclastic flow
Pyroclastic flow
A pyroclastic flow is a fast-moving current of superheated gas and rock , which reaches speeds moving away from a volcano of up to 700 km/h . The flows normally hug the ground and travel downhill, or spread laterally under gravity...
during the eruption that created the Long Valley Caldera
Long Valley Caldera
Long Valley Caldera is a depression in eastern California that is adjacent to Mammoth Mountain. The valley is one of the largest calderas on earth, measuring about long and wide . The elevation of the floor of the caldera is in the east and in the west...
. Large outcrops of the tuff are located in Inyo
Inyo County, California
-National protected areas:* Death Valley National Park * Inyo National Forest * Manzanar National Historic Site-Major highways:* U.S. Route 6* U.S. Route 395* State Route 127* State Route 136* State Route 168* State Route 178...
and Mono Counties
Mono County, California
Mono County is a county located in the east central portion of the U.S. state of California, to the east of the Sierra Nevada between Yosemite National Park and Nevada. As of the 2010 census, the population was 14,202, up from 12,853 at the 2000 census...
, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
Modern exposure
The Bishop Tuff caps a volcanic plateau in the northern Owens ValleyOwens Valley
Owens Valley is the arid valley of the Owens River in eastern California in the United States, to the east of the Sierra Nevada and west of the White Mountains and Inyo Mountains on the west edge of the Great Basin section...
. The tableland formation is located east of U.S. Route 395
U.S. Route 395 in California
In the U.S. state of California, U.S. Route 395 is a route which traverses from Interstate 15 near the southern city limits of Hesperia, north to the Oregon state line in Modoc County near Goose Lake...
and west of the Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...
stateline, sitting northwest of Bishop
Bishop, California
Bishop is a city in Inyo County, California, United States. Though Bishop is the only city and the largest populated place in Inyo County, the county seat is Independence. Bishop is located near the northern end of the Owens Valley, at an elevation of 4147 feet . The population was 3,879 at the...
and southeast of Crowley Lake
Crowley Lake
Crowley Lake is a reservoir on the upper Owens River in southern Mono County, California in the United States. It was created in 1941 by the Los Angeles Department of Water and Power as storage for the Los Angeles Aqueduct and for flood control...
and Mammoth Lakes
Mammoth Lakes, California
-History:The European history of Mammoth Lakes started in 1877, when four prospectors staked a claim on Mineral Hill, south of the current town, along Old Mammoth Road. In 1878, the Mammoth Mining Company was organized to mine Mineral Hill, which caused a gold rush. By the end of 1878, 1500 people...
. Another part of the flow is south of Mono Lake
Mono Lake
Mono Lake is a large, shallow saline lake in Mono County, California, formed at least 760,000 years ago as a terminal lake in a basin that has no outlet to the ocean...
, and surrounding the Mono-Inyo Craters
Mono-Inyo Craters
The Mono–Inyo Craters is a volcanic chain of craters, domes and lava flows in Eastern California that stretches from the northwest shore of Mono Lake to the south of Mammoth Mountain. The chain is located in Mono County in the U.S. state of California...
.
Deposits of Bishop Tuff in this area cover nearly 2200 square kilometre, and range in thickness from 150 metres (492.1 ft) to 200 metres (656.2 ft).
The Owens River
Owens River
The Owens River is a river in southeastern California in the United States, approximately long. It drains into and through the Owens Valley, an arid basin between the eastern slope of the Sierra Nevada and the western faces of the Inyo and White Mountains. The river terminates at Owens Lake, but...
cut through the volcanic plateau
Volcanic plateau
A volcanic plateau is a plateau produced by volcanic activity. There are two main types: lava plateaus and pyroclastic plateaus.-Lava plateau:...
, creating the Owens River Gorge
Owens River Gorge
The Owens River Gorge is a steep 10 mi canyon on the upper Owens River in eastern California in the United States. The canyon is located at the eastern edge of the Sierra Nevada mountains in southern Mono County, along the stretch of the river where it exits the Long Valley near its source...
.