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72-684: Originally, the volcano observatory was known as the Long Valley Observatory which monitored volcanic activity east of the Sierra Nevada in Mono County, California which included Long Valley Caldera , Mammoth Mountain , and the Mono–Inyo Craters . In 2012, the Long Valley Observatory was integrated into the new California Volcano Observatory based in Menlo Park, California which covers

144-753: A subduction zone where the crust of a sinking oceanic plate melts and drags water down with the subducting crust. Most volcanoes occur in a band encircling the Pacific Ocean (the Pacific Ring of Fire ), and in another that extends from the Mediterranean across Asia to join the Pacific band in the Indonesian Archipelago. The most important types of volcanic mountain are composite cones or stratovolcanoes and shield volcanoes . A shield volcano has

216-521: A foreman working for Sacramento pioneer John Sutter , found shiny metal in the tailrace of a lumber mill Marshall was building for Sutter on the American River . Rumors soon started to spread and were confirmed in March 1848 by San Francisco newspaper publisher and merchant Samuel Brannan . Brannan strode through the streets of San Francisco, holding aloft a vial of gold, shouting "Gold! Gold! Gold from

288-648: A gently sloping cone because of the low viscosity of the emitted material, primarily basalt . Mauna Loa is the classic example, with a slope of 4°-6°. (The relation between slope and viscosity falls under the topic of angle of repose . ) A composite volcano or stratovolcano has a more steeply rising cone (33°-40°), because of the higher viscosity of the emitted material, and eruptions are more violent and less frequent than for shield volcanoes. Examples include Vesuvius , Kilimanjaro , Mount Fuji , Mount Shasta , Mount Hood and Mount Rainier . When plates collide or undergo subduction (that is, ride one over another),

360-553: A portion of the area, a triangle whose vertices are Reno, Nevada ; Fresno, California ; and Las Vegas, Nevada , has been dubbed the " Nevada Triangle ", in reference to the Bermuda Triangle . Some counts put the number of crashes in the triangle at 2,000, including millionaire and record-breaking flyer Steve Fossett . Hypotheses that the crashes are related in some way to the United States Air Force 's Area 51 , or to

432-448: A powerful stream or jet of water at gold-bearing gravel beds. It is estimated that by the mid-1880s, 11 million troy ounces (340 metric tons) of gold (worth approximately US$ 16 billion in 2020 prices) had been recovered by "hydraulicking". A consequence of these extraction methods was that large amounts of gravel, silt , heavy metals , and other pollutants were washed into streams and rivers. As of 1999 , many areas still bear

504-682: A publication of his photographs under the title Parmelian Prints of the High Sierras , commented, "The name Sierra is already a plural. To add an s is a linguistic, Californian, and mountaineering sin." The Sierra Nevada lies primarily in Central and Eastern California , with the Carson Range , a small but historically important spur, extending into Nevada. West-to-east, the Sierra Nevada's elevation increases gradually from 500 feet (150 m) in

576-501: A short period, and the lightning can start fires. Summer high temperatures average 42–90 °F (6–32 °C). Winters are comparatively mild, and the temperature is usually only just low enough to sustain a heavy snowpack. For example, Tuolumne Meadows , at 8,600 feet (2,600 m) elevation, has winter daily highs about 40 °F (4 °C) with daily lows about 10 °F (−12 °C). The growing season lasts 20 to 230 days, strongly dependent on elevation. The highest elevations of

648-447: Is Mount Lyell (13,120 ft or 3,999 m). The Sierra rises to almost 14,000 feet (4,300 m) with Mount Humphreys near Bishop, California . Finally, near Lone Pine , Mount Whitney is at 14,505 feet (4,421 m), the highest point in the contiguous United States . South of Mount Whitney, the elevation of the range quickly dwindles. The crest elevation is almost 10,000 feet (3,000 m) near Lake Isabella , but south of

720-929: Is a mountain range in the Western United States , between the Central Valley of California and the Great Basin . The vast majority of the range lies in the state of California , although the Carson Range spur lies primarily in Nevada . The Sierra Nevada is part of the American Cordillera , an almost continuous chain of mountain ranges that forms the western "backbone" of the Americas. The Sierra runs 400 mi (640 km) north-south, and its width ranges from 50 mi (80 km) to 80 mi (130 km) across east–west. Notable features include General Sherman ,

792-416: Is called neotectonics . There are five main types of mountains: volcanic , fold , plateau , fault-block , and dome . A more detailed classification useful on a local scale predates plate tectonics and adds to these categories. Movements of tectonic plates create volcanoes along the plate boundaries, which erupt and form mountains. A volcanic arc system is a series of volcanoes that form near

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864-453: Is caused by horizontal compression acting on a thin to thick crust transition zone (as are all passive margins). Hotspots are supplied by a magma source in the Earth's mantle called a mantle plume . Although originally attributed to a melting of subducted oceanic crust, recent evidence belies this connection. The mechanism for plume formation remains a research topic. Several movements of

936-456: Is either protected from development or strictly managed. The mountain range is home to three National Parks  – Yosemite , Kings Canyon , and Sequoia  – and two national monuments  – Devils Postpile and Giant Sequoia . Ten national forests span much of the mountain range's remaining area. Within these national parks, monuments, and forests lie 26 wilderness areas , which together protect 15.4% of

1008-531: Is higher in the east. A list of biotic zones, and corresponding elevations, is presented below: Archaeological excavations placed Martis people of Paleo-Indians in northcentral Sierra Nevada during the period of 3,000 BCE to 500 CE. The earliest identified sustaining indigenous people in the Sierra Nevada were the Northern Paiute tribes on the east side, with the Mono tribe and Sierra Miwok tribe on

1080-691: Is no widely accepted geophysical model that explains elevated passive continental margins such as the Scandinavian Mountains , eastern Greenland , the Brazilian Highlands , or Australia's Great Dividing Range . Different elevated passive continental margins most likely share the same mechanism of uplift. This mechanism is possibly related to far-field stresses in Earth's lithosphere . According to this view elevated passive margins can be likened to giant anticlinal lithospheric folds, where folding

1152-415: Is not necessarily related to the geological structures found on it. From the late 18th century until its replacement by plate tectonics in the 1960s, geosyncline theory was used to explain much mountain-building. The understanding of specific landscape features in terms of the underlying tectonic processes is called tectonic geomorphology , and the study of geologically young or ongoing processes

1224-555: Is still possible for volcanoes to erupt on longer intervals than that. 37°27′23″N 122°10′17″W  /  37.45639°N 122.17139°W  / 37.45639; -122.17139 This volcanology article is a stub . You can help Misplaced Pages by expanding it . This article about a specific United States geological feature is a stub . You can help Misplaced Pages by expanding it . Sierra Nevada (U.S.) The Sierra Nevada ( / s i ˌ ɛr ə n ɪ ˈ v æ d ə , - ˈ v ɑː d -/ see- ERR -ə nih- VA(H)D -ə )

1296-688: Is the source of much of the sedimentary rock in California. In the Cretaceous , a subduction zone formed at the edge of the continent. This means that an oceanic plate started to dive beneath the North American Plate . Magma, formed through the subduction of the ancient Farallon Plate , rose in plumes ( plutons ) deep underground, their combined mass forming what is called the Sierra Nevada batholith . These plutons formed at various times, from 115  Ma to 87 Ma. The earlier plutons formed in

1368-458: The Basin and Range Province . As this andesitic volcanism began waning about five million years ago, the rivers were able to begin eroding away the 100s of meters of volcanic deposits and resume the incision that had been halted by the first period of volcanism. Some studies have argued that this recent incision is a sign of recent tectonic uplift. Other geologists claim that the elevations of many of

1440-634: The Carson River runs into Carson Sink , the Walker River into Walker Lake ; Rush , Lee Vining and Mill Creeks flow into Mono Lake ; and the Owens River into dry Owens Lake . Although none of the eastern rivers reach the sea, many of the streams from Mono Lake southwards are diverted into the Los Angeles Aqueduct which provides water to Southern California . The height of the mountains in

1512-481: The Central Valley to more than 14,000 feet (4,300 m) atop the highest peaks of its crest 50 to 75 miles (80 to 121 km) to the east. The east slope forms the steep Sierra Escarpment . Unlike its surroundings, the range receives a substantial amount of snowfall and precipitation due to orographic lift . The Sierra Nevada's irregular northern boundary stretches from the Susan River and Fredonyer Pass to

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1584-590: The Nevadan orogeny , granite formed deep underground. The range started to uplift less than five million years ago, and erosion by glaciers exposed the granite and formed the light-colored mountains and cliffs that make up the range. The uplift caused a wide range of elevations and climates in the Sierra Nevada, which are reflected by the presence of five life zones (areas with similar plant and animal communities). Uplift continues due to faulting caused by tectonic forces, creating spectacular fault block escarpments along

1656-587: The North Fork Feather River . It represents where the granitic bedrock of the Sierra Nevada dives below the southern extent of Cenozoic igneous surface rock from the Cascade Range . It is bounded on the west by California 's Central Valley , on the east by the Basin and Range Province , and on the southeast by the Mojave Desert . The southern boundary is at Tehachapi Pass . Physiographically,

1728-516: The San Joaquin Valley to the rest of the state in the 1870s. This facilitated the nationwide distribution of lumber. In addition, technological advancements, such as the shay locomotive and the v-shaped log flume , made it easier to transport lumber across mountainous terrain. The tourism potential of the Sierra Nevada was recognized early in the European history of the range. Yosemite Valley

1800-526: The United States started to move to California via Sonora and Walker Passes . In the winter of 1844, Lt. John C. Frémont , accompanied by Kit Carson , was the first European American to see Lake Tahoe . The Frémont party camped at 8,050 ft (2,450 m). The California Gold Rush began at Sutter's Mill , near Coloma , in the western foothills of the Sierra. On January 24, 1848, James W. Marshall,

1872-511: The endorheic basin of Tulare Lake , which rarely overflows into the San Joaquin during wet years. The eastern slope watershed of the Sierra is much narrower; its rivers flow out into the endorheic Great Basin of eastern California and western Nevada . From north to south, the Susan River flows into intermittent Honey Lake , the Truckee River flows from Lake Tahoe into Pyramid Lake ,

1944-716: The American River!" On August 19, 1848, the New York Herald was the first major newspaper on the East Coast to report the discovery of gold. On December 5, 1848, President James Polk confirmed the discovery of gold in an address to Congress . Soon, waves of immigrants from around the world, later called the "forty-niners", invaded the Gold Country of California or "Mother Lode". Miners lived in tents, wood shanties, or deck cabins removed from abandoned ships. Wherever gold

2016-713: The Pacific Ocean at San Francisco . The northern third of the western Sierra is part of the Sacramento River watershed (including the Feather , Yuba , and American River tributaries), and the middle third is drained by the San Joaquin River (including the Mokelumne , Stanislaus , Tuolumne , and Merced River tributaries). The southern third of the range is drained by the Kings , Kaweah , Tule , and Kern rivers, which flow into

2088-695: The Park in 1906. In the same year, Sequoia National Park was formed to protect the Giant Sequoia: all logging of the Sequoia ceased at that time. In 1903, the city of San Francisco proposed building a hydroelectric dam to flood Hetch Hetchy Valley . The city and the Sierra Club argued over the dam for 10 years, until the U.S. Congress passed the Raker Act in 1913 and allowed dam building to proceed. O'Shaughnessy Dam

2160-468: The Sierra Nevada increases gradually from north to south. Between Fredonyer Pass and Lake Tahoe, the peaks range from 5,000 feet (1,500 m) to more than 9,000 feet (2,700 m). The crest near Lake Tahoe is roughly 9,000 feet (2,700 m) high, with several peaks approaching the height of Freel Peak (10,881 ft or 3,317 m). Farther south, the highest peak in Yosemite National Park

2232-552: The Sierra Nevada is influenced by the Mediterranean climate of California. During the fall, winter and spring, precipitation in the Sierra ranges from 20 to 80 in (510 to 2,030 mm) where it occurs mostly as snow above 6,000 ft (1,800 m). Precipitation is highest on the central and northern portions of the western slope between 5,000 and 8,000 feet (1,500 and 2,400 m) elevation, due to orographic lift . Above 8,000 feet (2,400 m), precipitation diminishes on

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2304-499: The Sierra Nevada started in the early 1800s, when settlers relied on hand tools and ox-teams. Before the California Gold Rush, the industry was relatively small, and most of the lumber used in the state was imported. However, as the demand for lumber to support the mining industry increased, logging became a major industry in the region. Initially, most of the lumber produced in California was used in mining. The Comstock Lode

2376-431: The Sierra have an alpine climate . The Sierra Nevada snowpack is the major source of water and a significant source of electric power generation in California. Many reservoirs were constructed in the canyons of the Sierra throughout the 20th century, Several major aqueducts serving both agriculture and urban areas distribute Sierra water throughout the state. However, the Sierra casts a rain shadow , which greatly affects

2448-646: The Sierra is a section of the Cascade–Sierra Mountains province, which in turn is part of the larger Pacific Mountain System physiographic division. The California Geological Survey states that "the northern Sierra boundary is marked where bedrock disappears under the Cenozoic volcanic cover of the Cascade Range." The range is drained on its western slope by the Central Valley watershed, which discharges into

2520-493: The Sierra's 63,118 km (24,370 sq mi) from logging and grazing. The United States Forest Service and the Bureau of Land Management currently control 52% of the land in the Sierra Nevada. Logging and grazing are generally allowed on land controlled by these agencies, under federal regulations that balance recreation and development on the land. The California Bighorn Sheep Zoological Area near Mount Williamson in

2592-523: The Sierra. The combination of river and glacier erosion exposed the uppermost portions of the plutons emplaced millions of years before, leaving only a remnant of metamorphic rock on top of some Sierra peaks. Extension of the Basin and Range continues today, leading to downdropping of crustal blocks just east of the Sierra Nevada during large earthquakes, such as the Lone Pine earthquake of 1872. The climate of

2664-630: The Tuolumne and Merced River drainage. The group may have been the first non-indigenous people to see Yosemite Valley . The Walker Party probably visited either the Tuolumne or Merced Groves of giant sequoia , becoming the first non-indigenous people to see the giant trees, but journals relating to the Walker party were destroyed in 1839, in a print shop fire in Philadelphia. Starting in 1841, emigrants from

2736-444: The activities of extra-terrestrial aliens , have no evidence to support them. The Sierra Nevada is divided into a number of biotic zones , each of which is defined by its climate and supports a number of interdependent species. Life in the higher elevation zones adapted to colder weather, and to most of the precipitation falling as snow. The rain shadow of the Sierra causes the eastern slope to be warmer and drier: each life zone

2808-496: The area around Yosemite National Park and what would become Kings Canyon National Park . James S. Hutchinson , a noted mountaineer, climbed the Palisades (1904) and Mount Humphreys (1905). By 1912, the USGS published a set of maps of the Sierra Nevada, and the era of exploration was over. Logging in the Sierra Nevada has significantly impacted the landscape. The logging industry in

2880-521: The climate and ecology of the central Great Basin . This rain shadow is largely responsible for Nevada being the driest state in the United States. Precipitation varies substantially from year to year. It is not uncommon for some years to receive precipitation totals far above or below normal. The height of the range and the steepness of the Sierra Escarpment, particularly at the southern end of

2952-631: The crest and north of 37.2°N. In the Triassic and into the Jurassic , an island arc collided with the west coast of North America and raised a chain of volcanoes, in an event called the Nevadan orogeny . Nearly all subaerial Sierran Arc volcanoes have since disappeared; their remains were redeposited during the Great Valley Sequence and the subsequent Cenozoic filling of the Great Valley, which

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3024-407: The eastern edge of the southern Sierra. The Sierra Nevada has played an important role in the history of California and the United States. The California gold rush occurred in the western foothills from 1848 through 1855. Due to its inaccessibility, the range was not fully explored until 1912. Used in 1542 by Juan Rodríguez Cabrillo to describe a Pacific Coast Range ( Santa Cruz Mountains ),

3096-590: The entire states of California and Nevada, this includes the southern Cascade Range volcanoes in the state of California which were previously under the jurisdiction of the Cascades Volcano Observatory . These are the volcanoes monitored by the California Volcano Observatory, in order of highest to lowest risk assessment. According to USGS risk assessment of the volcanoes in CalVO's region,

3168-484: The following volcanoes were ranked "very high threat potential". These were ranked "high threat potential": These were ranked "moderate threat potential": One was ranked "Low to Very Low Threat Potential": Other volcanoes in the region have not been assessed at one of these risk levels that warrant monitoring. Volcanoes which have not erupted during the Holocene were not included. USGS noted that though less probable it

3240-556: The highest mountain front in the continental United States. Another example is the Rila – Rhodope massif in Bulgaria , including the well defined horsts of Belasitsa (linear horst), Rila mountain (vaulted domed shaped horst) and Pirin mountain —a horst forming a massive anticline situated between the complex graben valleys of the Struma and Mesta rivers. Unlike orogenic mountains there

3312-459: The highest peak in the range. In 1873, Mount Whitney was climbed for the first time by 3 men from Lone Pine, California, on a fishing trip. From 1892 to 1897 Theodore Solomons made the first attempt to map a route along the crest of the Sierra. Other people finished exploring and mapping the Sierra. Bolton Coit Brown explored the Kings River watershed in 1895–1899. Joseph N. LeConte mapped

3384-511: The lake, the peaks reach only a modest 8,000 feet (2,400 m). There are several notable geographical features in the Sierra Nevada: Communities in the Sierra Nevada include Paradise , South Lake Tahoe , Truckee , Grass Valley , Lee Vining , Mammoth Lakes , Sonora , Nevada City , Placerville , Pollock Pines , Portola , Auburn , Colfax and Kennedy Meadows . Much of the Sierra Nevada consists of federal lands and

3456-676: The largest tree in the world by volume; Lake Tahoe , the largest alpine lake in North America; Mount Whitney at 14,505 ft (4,421 m), the highest point in the contiguous United States ; and Yosemite Valley sculpted by glaciers from one-hundred-million-year-old granite , containing high waterfalls . The Sierra is home to three national parks , twenty-six wilderness areas, ten national forests, and two national monuments. These areas include Yosemite , Sequoia , and Kings Canyon National Parks , as well as Devils Postpile National Monument . More than one hundred million years ago during

3528-487: The late 1800s due to several factors. The Timber and Stone Act of 1878 allowed individuals to claim ownership of old-growth timber tracts, which were later consolidated under joint-stock companies , such as those founded by Midwestern lumber magnates. These companies had the financial resources to transport timber from remote locations and build sawmills near the tracks of the Southern Pacific railroad which connected

3600-455: The late 1800s, the logging industry moved westward due to the depletion of white pine forests in the upper Midwest. This shift was encouraged by the positive portrayal of the Sierra Nevada as a promising timber region. In 1859, Horace Greely marveled, "I never saw anything so much like good timber in the course of any seventy-five miles' travel as I saw in crossing the Sierra Nevada." The logging industry experienced significant growth in

3672-487: The miners, provoking counter-attacks on native villages. The Native Americans, out-gunned, were often slaughtered. The Gold Rush populated the western foothills of the Sierra Nevada, but even by 1860, most of the Sierra was unexplored. The state legislature authorized the California Geological Survey to officially explore the Sierra (and survey the rest of the state). Josiah Whitney was appointed to head

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3744-440: The modern rivers flowing down the range are only 100–300 meters (300–1,000 ft) lower than their ancient counterparts from 30–40 million years ago and the overall elevation and bedrock topography of the northern Sierra Nevada has changed little since at least 30–40 million years ago. About 2.5 Ma, the Earth's climate cooled, and ice ages started. Glaciers carved out characteristic U-shaped canyons throughout

3816-688: The mountains were amongst a group led by fur trapper Jedediah Smith , crossing north of the Yosemite area in May 1827, at Ebbetts Pass . In 1833, a subgroup of the Bonneville Expedition led by Joseph Reddeford Walker was sent westward to find an overland route to California . Eventually the party discovered a route along the Humboldt River across present-day Nevada , ascending the Sierra Nevada, starting near present-day Bridgeport and descending between

3888-409: The mountains. Washo and Maidu were also in this area prior to the era of European exploration and displacement. American exploration of the mountain range started in 1827. Although prior to the 1820s there were Spanish missions , pueblos (towns), presidios (forts), and ranchos along the coast of California, no Spanish explorers visited the Sierra Nevada. The first Americans to visit

3960-399: The northern Sierran valleys with volcanic deposits. These pyroclastic flows, which continued for about 10 million years, were followed by andesitic lahars which nearly completely buried the northern Sierran landscape such that only the tallest peaks emerged above a volcanic plain. This second period of volcanism appears to have been triggered by crustal extension associated with extension of

4032-399: The oldest being metasedimentary rocks from the Cambrian in the Mount Morrison region. These dark-colored hornfels , slates , marbles , and schists are found in the western foothills (notably around Coarsegold , west of the Tehachapi Pass ) and east of the Sierra Crest. The earliest granite of the Sierra started to form in the Triassic period. This granite is mostly found east of

4104-406: The plates tend to buckle and fold , forming mountains. Most of the major continental mountain ranges are associated with thrusting and folding or orogenesis . Examples are the Balkan Mountains , the Jura and the Zagros mountains. When a fault block is raised or tilted, a block mountain can result. Higher blocks are called horsts , and troughs are called grabens . A spreading apart of

4176-413: The plural ( Smokies , Rockies , Cascades , etc.), since Sierra is already pluralized in its native language, some locals who live in "the Sierra" are not hesitant to admonish those who refer to the area as "the Sierras". However, there are historical and literary references that use the plural, such as the 1871 collection of Joaquin Miller poems, Songs of the Sierras . Ansel Adams , in response to

4248-420: The range, produces a wind phenomenon known as the "Sierra Rotor". This is a horizontal rotation of the atmosphere just east of the crest of the Sierra, set in motion as an effect of strong westerly winds. Because of the large number of airplanes that have crashed in the Sierra Nevada, primarily due to the complex weather and atmospheric conditions such as downdrafts and microbursts caused by geography there,

4320-502: The scars of hydraulic mining, since the resulting exposed earth and downstream gravel deposits do not support plant life. It is estimated that by 1855, at least 300,000 gold-seekers, merchants, and other immigrants had arrived in California from around the world. The huge numbers of newcomers brought by the Gold Rush drove Native Americans out of their traditional hunting, fishing and food-gathering areas. To protect their homes and livelihood, some Native Americans responded by attacking

4392-407: The southern Sierra was established to protect the endangered Sierra Nevada bighorn sheep . Starting in 1981, hikers were unable to enter the Area from May 15 through December 15, in order to protect the sheep. As of 2010, the restriction has been lifted and access to the Area is open for the whole year. The earliest rocks in the Sierra Nevada are metamorphic roof pendants of Paleozoic age,

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4464-422: The surface causes tensional forces. When the tensional forces are strong enough to cause a plate to split apart, it does so such that a center block drops down relative to its flanking blocks. An example is the Sierra Nevada range, where delamination created a block 650 km long and 80 km wide that consists of many individual portions tipped gently west, with east facing slips rising abruptly to produce

4536-425: The survey. Men of the survey, including William H. Brewer , Charles F. Hoffmann and Clarence King , explored the backcountry of what would become Yosemite National Park in 1863. In 1864, they explored the area around Kings Canyon . In 1869, John Muir started his wanderings in the Sierra Nevada range, and in 1871, King was the first to climb Mount Langley , mistakenly believing he had summited Mount Whitney ,

4608-490: The term "Sierra Nevada" was a general identification of less familiar ranges toward the interior. In 1776, Pedro Font 's map applied the name to the range currently known as the Sierra Nevada. The literal translation is "snowy mountains", from sierra "a range of mountains", 1610s, from Spanish sierra "jagged mountain range", lit. "saw", from Latin serra "a saw"; and from fem. of Spanish nevado "snowy". While many mountain ranges are unanimously referred to in

4680-424: The water from an entire river into a sluice alongside the river, and then dig for gold in the newly exposed river bottom. By 1853, most of the easily accessible gold had been collected, and attention turned to extracting gold from more difficult locations. Hydraulic mining was used on ancient gold-bearing gravel beds on hillsides and bluffs in the gold fields. In hydraulic mining, a high-pressure hose directed

4752-470: The western half of the Sierra, while the later plutons formed in the eastern half of the Sierra. At this time, the Sierra Nevada formed the western ramp of a high plateau to the east, the Nevadaplano . During this period, rivers cut deep canyons into the range, generating topographic relief similar to the modern Sierra Nevada. This period of incision was halted approximately 30 million years ago by vast outpourings of pyroclastic flows from Nevada which filled

4824-401: The western side, and the Kawaiisu and Tübatulabal tribes in the southern Sierra. Today, some historic intertribal trade route trails over mountain passes are known artifact locations, such as Duck Pass with its obsidian arrowheads . The California and Sierra Native American tribes were predominantly peaceful, with occasional territorial disputes between the Paiute and Sierra Miwok tribes in

4896-437: The western slope up to the crest, since most of the precipitation has been wrung out at lower elevations. Most parts of the range east of the crest are in a rain shadow , and receive less than 25 inches of precipitation per year. While most summer days are dry, afternoon thunderstorms are common, particularly during the North American Monsoon in mid and late summer. Some of these summer thunderstorms drop over an inch of rain in

4968-407: Was a major center for logging, with operations supplying lumber for the construction of mine structures, such as tunnels, shafts, and buildings, as well as fuel for the mines. Dan DeQuille observed in 1876, "the Comstock Lode may truthfully be said to be the tomb of the forests of the Sierra. Millions upon millions of feet of lumber are annually buried in the mines, nevermore to be resurrected.” In

5040-434: Was completed in 1923. Mountain formation Mountain formation refers to the geological processes that underlie the formation of mountains . These processes are associated with large-scale movements of the Earth's crust ( tectonic plates ). Folding , faulting , volcanic activity , igneous intrusion and metamorphism can all be parts of the orogenic process of mountain building. The formation of mountains

5112-421: Was discovered, hundreds of miners would collaborate to put up a camp and stake their claims. Because the gold in the California gravel beds was so richly concentrated, the early forty-niners simply panned for gold in California's rivers and streams. However, panning cannot take place on a large scale, and miners and groups of miners graduated to more complex placer mining. Groups of prospectors would divert

5184-440: Was first protected by the federal government in 1864. The Valley and Mariposa Grove were ceded to California in 1866 and turned into a state park. John Muir perceived overgrazing by sheep and logging of giant sequoia to be a problem in the Sierra. Muir successfully lobbied for the protection of the rest of Yosemite National Park: Congress created an Act to protect the park in 1890. The Valley and Mariposa Grove were added to

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