Devils Postpile National Monument
Encyclopedia
Devils Postpile National Monument is located near Mammoth Mountain
Mammoth Mountain
Mammoth Mountain is a lava dome complex west of the town of Mammoth Lakes, California in the Inyo National Forest of Madera County and Mono County. It is home to a large ski area on the Mono County side....

 in extreme northeastern Madera County
Madera County, California
Madera County is a county of the U.S. state of California, located in the Central Valley and the Sierra Nevada north of Fresno County. It comprises the Madera-Chowchilla, CA Metropolitan Statistical Area. As of the 2010 census the population was 150,865...

 in eastern California
Eastern California
Eastern California is a term that refers to the eastern region of California, United States. It can refer to either the strip to the east of the crest of the Sierra Nevada, or to the easternmost counties of California.-Culture and history:...

. It was established in 1911, and protects Devils Postpile, an unusual formation of columnar basalt.

Geography

Devils Postpile National Monument contains 798 acre and includes two main tourist attractions: Devils Postpile (a columnar basalt formation); and Rainbow Falls
Rainbow Falls (California)
Rainbow Falls is the highest waterfall on the Middle Fork of the San Joaquin River, California, United States. Plunging 101-feet down to the turbulent water below, the falls are named for the rainbows that appear in its mist throughout sunny summer days....

, a waterfall on the Middle Fork of the San Joaquin River
San Joaquin River
The San Joaquin River is the largest river of Central California in the United States. At over long, the river starts in the high Sierra Nevada, and flows through a rich agricultural region known as the San Joaquin Valley before reaching Suisun Bay, San Francisco Bay, and the Pacific Ocean...

. In addition, the John Muir Trail
John Muir Trail
The John Muir Trail is a long-distance trail in the Sierra Nevada mountain range of California, running between the northern terminus at Happy Isles in Yosemite Valley and the southern terminus located on the summit of Mount Whitney . For almost all of its length, the trail is in the High Sierra...

 and Pacific Crest Trail
Pacific Crest Trail
The Pacific Crest Trail is a long-distance mountain hiking and equestrian trail on the Western Seaboard of the United States. The southern terminus is at the California border with Mexico...

 merge into one trail as they pass through the monument.

History

Devils Postpile National Monument was once part of Yosemite National Park
Yosemite National Park
Yosemite National Park is a United States National Park spanning eastern portions of Tuolumne, Mariposa and Madera counties in east central California, United States. The park covers an area of and reaches across the western slopes of the Sierra Nevada mountain chain...

, but discovery of gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...

 in 1905 near 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...

 prompted a boundary change that left the Postpile on adjacent public land
Public land
In all modern states, some land is held by central or local governments. This is called public land. The system of tenure of public land, and the terminology used, varies between countries...

. A proposal to build a hydroelectric dam later called for blasting the Postpile into the river. Influential Californians, including Walter L. Huber, persuaded the federal government to stop the demolition and in 1911, President William Howard Taft
William Howard Taft
William Howard Taft was the 27th President of the United States and later the tenth Chief Justice of the United States...

 made the area into a United States National Monument.

Flora and fauna

The flora and fauna at Devils Postpile are typical of the Sierra Nevada. The Monument contains animals and plants such as black bear
American black bear
The American black bear is a medium-sized bear native to North America. It is the continent's smallest and most common bear species. Black bears are omnivores, with their diets varying greatly depending on season and location. They typically live in largely forested areas, but do leave forests in...

s, pine marten
American Marten
The American marten is a North American member of the family Mustelidae, sometimes referred to as the pine marten. The name "pine marten" is derived from the common but distinct Eurasian species of Martes...

s, mule deer
Mule Deer
The mule deer is a deer indigenous to western North America. The Mule Deer gets its name from its large mule-like ears. There are believed to be several subspecies, including the black-tailed deer...

, coyote
Coyote
The coyote , also known as the American jackal or the prairie wolf, is a species of canine found throughout North and Central America, ranging from Panama in the south, north through Mexico, the United States and Canada...

s, quaking aspen, black cottonwood, alder
Alder
Alder is the common name of a genus of flowering plants belonging to the birch family . The genus comprises about 30 species of monoecious trees and shrubs, few reaching large size, distributed throughout the North Temperate Zone and in the Americas along the Andes southwards to...

, and willow
Willow
Willows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...

s, as well as many wildflowers, such as cinquefoil and alpine shooting star
Dodecatheon alpinum
Dodecatheon alpinum is a species of flowering plant in the primrose family known by the common name alpine shooting star. This wildflower is native to the Southwestern United States where it grows in wet areas in mountains, such as the Sierra Nevada....

. Dark-eyed junco
Dark-eyed Junco
The Dark-eyed Junco is the best-known species of the juncos, a genus of small grayish American sparrows. This bird is common across much of temperate North America and in summer ranges far into the Arctic...

s and white-crowned sparrow
White-crowned Sparrow
The White-crowned Sparrow is a medium-sized sparrow native to North America.- Description :Adults are long and have black and white stripes on their head, a grey face, brown streaked upper parts and a long tail. The wings are brown with bars and the underparts are grey. Their bill is pink or yellow...

s are common in the summer.

Devils Postpile

Devils Postpile itself is a dark cliff of columnar basalt created by a lava flow sometime between less than 100,000 years ago (according to current potassium-argon dating
Potassium-argon dating
Potassium–argon dating or K–Ar dating is a radiometric dating method used in geochronology and archeology. It is based on measurement of the product of the radioactive decay of an isotope of potassium into argon . Potassium is a common element found in many materials, such as micas, clay minerals,...

) to 700,000 years ago (according to other dating methods). The source of the lava is thought to have been somewhere near Upper Soda Springs campground at the north end of Pumice Flat on the floor of the Middle Fork of the San Joaquin River
San Joaquin River
The San Joaquin River is the largest river of Central California in the United States. At over long, the river starts in the high Sierra Nevada, and flows through a rich agricultural region known as the San Joaquin Valley before reaching Suisun Bay, San Francisco Bay, and the Pacific Ocean...

, from where it flowed to the site of the Postpile, was impounded by a moraine
Moraine
A moraine is any glacially formed accumulation of unconsolidated glacial debris which can occur in currently glaciated and formerly glaciated regions, such as those areas acted upon by a past glacial maximum. This debris may have been plucked off a valley floor as a glacier advanced or it may have...

, and reached a thickness of 400 feet (newer estimate) to 600 feet (older estimate). In any event, the lava that now makes up the Postpile was near the bottom of this mass.

Because of its great thickness, much of the mass of pooled lava cooled slowly and evenly, which is why the columns are so long and so symmetrical. Columnar jointing occurs when certain types of lava cool; the joints develop when the lava contracts during the cooling process.

A glacier
Glacier
A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...

 later removed much of this mass of rock and left a nicely polished surface on top of the Postpile with very noticeable glacial striations
Glacial striations
Glacial striations or glacial grooves are scratches or gouges cut into bedrock by process of glacial abrasion. Glacial striations usually occur as multiple straight, parallel grooves representing the movement of the sediment-loaded base of the glacier...

 and glacial polish
Glacial polish
Glacial polish is a characteristic of rock surfaces where glaciers have passed over bedrock, typically granite or other hard igneous or metamorphic rock. Moving ice will carry pebbles and sand grains removed from upper levels which in turn grind a smooth or grooved surface upon the underlying rock...

.

The Postpile's columns average 2 foot (0.6096 m) in diameter, the largest being 3.5 feet (1.1 m), and many are up to 60 feet (18.3 m) long. Together they look like tall posts stacked in a pile, hence the feature's name. If the lava had cooled perfectly evenly, all of the columns would be expected to be hexagonal, but some of the columns have different polygonal cross-sections due to variations in cooling. A survey of 400 of the Postpile's columns found that 44.5% were 6-sided, 37.5% 5-sided, 9.5% 4-sided, 8.0% 7-sided, and 0.5% 3-sided. Compared with other examples of columnar jointing, the Postpile has more hexagonal columns. Another feature that places the Postpile in a special category is the lack of horizontal jointing.

Several stones from the Devil's Postpile can be seen at the entrance to the United States Geological Survey
United States Geological Survey
The United States Geological Survey is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization has four major science disciplines, concerning biology,...

 headquarters lot in Reston, Virginia
Reston, Virginia
Reston is a census-designated place in Fairfax County, Virginia, United States, within the Washington, D.C. metropolitan area. The population was 58,404, at the 2010 Census and 56,407 at the 2000 census...

.

Similar structures

Although the basaltic columns are impressive, they are not unique. Basalt columns are a common volcanic feature, and they occur on many scales (faster cooling produces smaller columns). Other notable sites include Giant's Causeway
Giant's Causeway
The Giant's Causeway is an area of about 40,000 interlocking basalt columns, the result of an ancient volcanic eruption. It is located in County Antrim on the northeast coast of Northern Ireland, about three miles northeast of the town of Bushmills...

 in Northern Ireland
Northern Ireland
Northern Ireland is one of the four countries of the United Kingdom. Situated in the north-east of the island of Ireland, it shares a border with the Republic of Ireland to the south and west...

, Fingal's Cave
Fingal's Cave
Fingal's Cave is a sea cave on the uninhabited island of Staffa, in the Inner Hebrides of Scotland, part of a National Nature Reserve owned by the National Trust for Scotland. It is formed entirely from hexagonally jointed basalt columns, similar in structure to the Giant's Causeway in Northern...

 in Scotland, Titan's Piazza of the Mount Holyoke Range in Massachusetts
Massachusetts
The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...

, the Garni Gorge
Garni Gorge
The Garni Gorge is situated 23 km east of Yerevan, Armenia, just below the village with the same name. On a promontory above the gorge, the 1st century AD Garni temple may be seen. Along the sides of the gorge are cliff walls of well preserved basalt columns, carved out by the Goght River. This...

 in Armenia
Armenia
Armenia , officially the Republic of Armenia , is a landlocked mountainous country in the Caucasus region of Eurasia...

, the Cyclopean Isles
Cyclopean Isles
The Cyclopean Isles, noted for their rows of basaltic columns piled one above another, lie not far from Mount Etna off the eastern coast of Sicily in the Mediterranean Sea.-Geology:...

 near Sicily
Sicily
Sicily is a region of Italy, and is the largest island in the Mediterranean Sea. Along with the surrounding minor islands, it constitutes an autonomous region of Italy, the Regione Autonoma Siciliana Sicily has a rich and unique culture, especially with regard to the arts, music, literature,...

, Sheepeater Cliff
Sheepeater Cliff
The Sheepeater Cliffs are a series of exposed cliffs made up of columnar basalt in Yellowstone National Park in the United States. The lava was deposited about 500,000 years ago during one of the periodic basaltic floods in Yellowstone Caldera, and later exposed by the Gardner River...

 at Yellowstone National Park
Yellowstone National Park
Yellowstone National Park, established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872, is a national park located primarily in the U.S. state of Wyoming, although it also extends into Montana and Idaho...

 in Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

, Prismas Basálticos in Huasca de Ocampo
Huasca de Ocampo
Huasca de Ocampo is a town and municipality of the state of Hidalgo in central Mexico. It is located 34 km from Pachuca and 16 km from Real del Monte in the Sierra de Pachuca Mountains. While the town itself it just within the mountain range, much of the municipal land in located in a...

, Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

, the "Organ Pipes" formation on Mount Cargill
Mount Cargill
Mount Cargill is a 680 metre high volcanic outcrop which dominates the skyline of northern Dunedin, New Zealand. It is situated some 15 kilometres north of the city centre....

 in New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

, Gilbert Hill
Gilbert Hill
Gilbert Hill is a monolith column of black basalt rock in Andheri, in Mumbai, India. The rock has a sheer vertical face and was formed when molten lava was squeezed out of the Earth's clefts during the Mesozoic Era about 65 million years ago. During that era, molten lava had spread around most of...

 in Mumbai
Mumbai
Mumbai , formerly known as Bombay in English, is the capital of the Indian state of Maharashtra. It is the most populous city in India, and the fourth most populous city in the world, with a total metropolitan area population of approximately 20.5 million...

, Organ Pipes National Park
Organ Pipes National Park
The Organ Pipes National Park , a protected area, is located in Victoria, Australia. It was established with the focus on conservation of the native flora and fauna, and preservation of the geological features in the Jackson Creek, a part of the Maribyrnong valley, north-west of Melbourne...

 in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 and the "Columnar Cape" (Russian: Mis Stolbchaty) on Kunashir Island
Kunashir Island
Kunashir Island , possibly meaning Black Island or Grass Island in Ainu, is the southernmost island of the Kuril Islands, which are controlled by Russia and claimed by Japan ....

, the southernmost of the Kuril Islands
Kuril Islands
The Kuril Islands , in Russia's Sakhalin Oblast region, form a volcanic archipelago that stretches approximately northeast from Hokkaidō, Japan, to Kamchatka, Russia, separating the Sea of Okhotsk from the North Pacific Ocean. There are 56 islands and many more minor rocks. It consists of Greater...

. Columnar basalt can also be seen in a high desert dry river falls area just north of Lajitas, Texas
Lajitas, Texas
Lajitas is an unincorporated community in Brewster County, Texas, United States, in proximity to the Big Bend National Park.-Government:For many years the mayor of Lajitas was Clay Henry III, a "beer-drinking" goat...

. The much more massive Devils Tower National Monument
Devils Tower National Monument
Devils Tower is an igneous intrusion or laccolith located in the Black Hills near Hulett and Sundance in Crook County, northeastern Wyoming, above the Belle Fourche River...

 in Wyoming is superficially similar but consists of a phonolite
Phonolite
Phonolite is a rare igneous, volcanic rock of intermediate composition, with aphanitic to porphyritic texture....

 porphyry
Porphyry (geology)
Porphyry is a variety of igneous rock consisting of large-grained crystals, such as feldspar or quartz, dispersed in a fine-grained feldspathic matrix or groundmass. The larger crystals are called phenocrysts...

, formed by the intrusion
Intrusion
An intrusion is liquid rock that forms under Earth's surface. Magma from under the surface is slowly pushed up from deep within the earth into any cracks or spaces it can find, sometimes pushing existing country rock out of the way, a process that can take millions of years. As the rock slowly...

 of igneous rock
Igneous rock
Igneous rock is one of the three main rock types, the others being sedimentary and metamorphic rock. Igneous rock is formed through the cooling and solidification of magma or lava...

.

See also

  • Gilbert Hill
    Gilbert Hill
    Gilbert Hill is a monolith column of black basalt rock in Andheri, in Mumbai, India. The rock has a sheer vertical face and was formed when molten lava was squeezed out of the Earth's clefts during the Mesozoic Era about 65 million years ago. During that era, molten lava had spread around most of...

  • Little Devils Postpile
    Little Devils Postpile
    Little Devils Postpile, in Yosemite National Park in California, United States, is a set of columnar joints in a basalt plug resembling the Devils Postpile formation. It is located along the Tuolumne River a few miles west of Tuolumne Meadows.-See also:...


Category: Rock formations in California

External links

Malheur Butte
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