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116-700: In the early 1900s, the Owens River was the focus of the California Water Wars , fought between the city of Los Angeles and the inhabitants of Owens Valley over the construction of the Los Angeles Aqueduct . Since 1913, the Owens River has been diverted to Los Angeles, causing the ruin of the valley's economy and the drying of Owens Lake. In winter 2006, the Los Angeles Department of Water and Power restored 5% of

232-459: A combination of these processes. Other mechanisms, such as melting from a meteorite impact , are less important today, but impacts during the accretion of the Earth led to extensive melting, and the outer several hundred kilometres of our early Earth was probably an ocean of magma. Impacts of large meteorites in the last few hundred million years have been proposed as one mechanism responsible for

348-405: A crystalline basement formed of a great variety of metamorphic and igneous rocks, including granulite and granite. Oceanic crust is composed primarily of basalt and gabbro . Both continental and oceanic crust rest on peridotite of the mantle. Rocks may melt in response to a decrease in pressure, to a change in composition (such as an addition of water), to an increase in temperature, or to

464-603: A desert. Mulholland was blocked from obtaining additional water from the Colorado River, so decided to take all available water from the Owens Valley. In 1923, farmers and ranchers formed an irrigation cooperative headed by Wilfred and Mark Watterson, owners of the Inyo County Bank. By exploiting personal bitterness of some of the farmers, Los Angeles managed to acquire some of the key water rights of

580-598: A few local Inyo County people. Eaton bought land as a private citizen, hoping to sell it back to Los Angeles at a tidy profit. Eaton claimed in an interview with the Los Angeles Express in 1905 that he turned over all his water rights to the City of Los Angeles without being paid for them, "except that I retained the cattle which I had been compelled to take in making the deals ... and mountain pasture land of no value except for grazing purposes". Eaton moved to

696-527: A huge mass of analytical data—over 230,000 rock analyses can be accessed on the web through a site sponsored by the U. S. National Science Foundation (see the External Link to EarthChem). The single most important component is silica, SiO 2 , whether occurring as quartz or combined with other oxides as feldspars or other minerals. Both intrusive and volcanic rocks are grouped chemically by total silica content into broad categories. This classification

812-653: A microscope for fine-grained volcanic rock, and may be impossible for glassy volcanic rock. The rock must then be classified chemically. Mineralogical classification of an intrusive rock begins by determining if the rock is ultramafic, a carbonatite, or a lamprophyre . An ultramafic rock contains more than 90% of iron- and magnesium-rich minerals such as hornblende, pyroxene, or olivine, and such rocks have their own classification scheme. Likewise, rocks containing more than 50% carbonate minerals are classified as carbonatites, while lamprophyres are rare ultrapotassic rocks. Both are further classified based on detailed mineralogy. In

928-535: A political dispute in Washington. Los Angeles needed rights of way across federal land to build the aqueduct. California Senator Frank Flint sponsored a bill to grant the rights of way, but Congressman Sylvester Smith of Inyo County opposed the bill. Smith argued that irrigating Southern California was not more valuable than irrigating Owens Valley. While a compromise was being negotiated, Flint appealed to President Roosevelt. Roosevelt met with Flint, Secretary of

1044-612: A reliable water supply for Los Angeles. In 1997, Inyo County, Los Angeles, the Owens Valley Committee , the Sierra Club , and other concerned parties signed a Memorandum of Understanding that specified terms by which the lower Owens River would be re-watered by June 2003 as partial mitigation for damage to the Owens Valley. In spite of the terms of the Long Term Water Agreement, studies by

1160-422: A result of water diversion put this species at risk, as well as the birds that nested on two islands ( Negit Island and Paoha Island ) in the lake. Falling water levels started making a land bridge to Negit Island, which allowed predators to feed on bird eggs for the first time. In 1974, David Gaines started to study the biology of Mono Lake. In 1975, while at Stanford, he started to get others interested in

1276-553: A simplified compositional classification, igneous rock types are categorized into felsic or mafic based on the abundance of silicate minerals in the Bowen's Series. Rocks dominated by quartz, plagioclase, alkali feldspar and muscovite are felsic. Mafic rocks are primarily composed of biotite, hornblende, pyroxene and olivine. Generally, felsic rocks are light colored and mafic rocks are darker colored. For textural classification, igneous rocks that have crystals large enough to be seen by

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1392-591: A small filing fee and a charge of $ 1.25 per acre. The Homestead Act limited the land an individual could own to 160 acres (64.7 ha) in order to create small farms. The amount of public land settled by the late 1870s and early 1880s was still relatively small. The Desert Land Act of 1877 allowed individuals to acquire more area, up to 640 acres (259.0 ha) , in hopes of drawing more settlers by giving them enough land to make their settlement and land expenses worthwhile, but "included no residency requirements". By 1886, rapid acquisition of land had begun and by

1508-462: A viscosity similar to thick, cold molasses or even rubber when erupted. Felsic magma, such as rhyolite , is usually erupted at low temperature and is up to 10,000 times as viscous as basalt. Volcanoes with rhyolitic magma commonly erupt explosively, and rhyolitic lava flows are typically of limited extent and have steep margins because the magma is so viscous. Felsic and intermediate magmas that erupt often do so violently, with explosions driven by

1624-511: A vital ecosystem link, where gulls and migratory birds would nest. Because the creeks were diverted, the water level in Mono Lake started to fall, exposing tufa formations. The water became more saline and alkaline, threatening the brine shrimp that lived in the lake. Increases in salinity decreased adult size, growth rates, and brood sizes, and increased female mortality during their reproductive cycle . Changing levels in salinity as

1740-569: A wide range of geological settings: shields, platforms, orogens, basins, large igneous provinces, extended crust and oceanic crust. Igneous and metamorphic rocks make up 90–95% of the top 16 kilometres (9.9 mi) of the Earth's crust by volume. Igneous rocks form about 15% of the Earth's current land surface. Most of the Earth's oceanic crust is made of igneous rock. Igneous rocks are also geologically important because: Igneous rocks can be either intrusive ( plutonic and hypabyssal) or extrusive ( volcanic ). Intrusive igneous rocks make up

1856-583: A word for beaver su-i'-tu-ti-kut'-teh . When Stephen Powers visited the northern Paiute to collect Indian materials for the Smithsonian Institution in preparation for the Centennial Exhibition of 1876 , he reported that the northern Paiute wrapped their hair in strips of beaver fur, made medicine from parts of beaver and that their creation legend included beaver. In addition, fur trapper Stephen Hall Meek "set his traps on

1972-584: Is an example. The molten rock, which typically contains suspended crystals and dissolved gases, is called magma . It rises because it is less dense than the rock from which it was extracted. When magma reaches the surface, it is called lava . Eruptions of volcanoes into air are termed subaerial , whereas those occurring underneath the ocean are termed submarine . Black smokers and mid-ocean ridge basalt are examples of submarine volcanic activity. The volume of extrusive rock erupted annually by volcanoes varies with plate tectonic setting. Extrusive rock

2088-728: Is distinguishable from the other two on the TAS diagram, being higher in total alkali oxides for a given silica content, but the tholeiitic and calc-alkaline series occupy approximately the same part of the TAS diagram. They are distinguished by comparing total alkali with iron and magnesium content. These three magma series occur in a range of plate tectonic settings. Tholeiitic magma series rocks are found, for example, at mid-ocean ridges, back-arc basins , oceanic islands formed by hotspots, island arcs and continental large igneous provinces . All three series are found in relatively close proximity to each other at subduction zones where their distribution

2204-595: Is expressed differently for major and minor elements and for trace elements. Contents of major and minor elements are conventionally expressed as weight percent oxides (e.g., 51% SiO 2 , and 1.50% TiO 2 ). Abundances of trace elements are conventionally expressed as parts per million by weight (e.g., 420 ppm Ni, and 5.1 ppm Sm). The term "trace element" is typically used for elements present in most rocks at abundances less than 100 ppm or so, but some trace elements may be present in some rocks at abundances exceeding 1,000 ppm. The diversity of rock compositions has been defined by

2320-506: Is formed by the cooling of molten magma on the earth's surface. The magma, which is brought to the surface through fissures or volcanic eruptions , rapidly solidifies. Hence such rocks are fine-grained ( aphanitic ) or even glassy. Basalt is the most common extrusive igneous rock and forms lava flows, lava sheets and lava plateaus. Some kinds of basalt solidify to form long polygonal columns . The Giant's Causeway in Antrim, Northern Ireland

2436-436: Is most often used to classify plutonic rocks. Chemical classifications are preferred to classify volcanic rocks, with phenocryst species used as a prefix, e.g. "olivine-bearing picrite" or "orthoclase-phyric rhyolite". The IUGS recommends classifying igneous rocks by their mineral composition whenever possible. This is straightforward for coarse-grained intrusive igneous rock, but may require examination of thin sections under

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2552-496: Is produced in the following proportions: The behaviour of lava depends upon its viscosity , which is determined by temperature, composition, and crystal content. High-temperature magma, most of which is basaltic in composition, behaves in a manner similar to thick oil and, as it cools, treacle . Long, thin basalt flows with pahoehoe surfaces are common. Intermediate composition magma, such as andesite , tends to form cinder cones of intermingled ash , tuff and lava, and may have

2668-402: Is related to depth and the age of the subduction zone. The tholeiitic magma series is well represented above young subduction zones formed by magma from relatively shallow depth. The calc-alkaline and alkaline series are seen in mature subduction zones, and are related to magma of greater depths. Andesite and basaltic andesite are the most abundant volcanic rock in island arc which is indicative of

2784-487: Is summarized in the following table: The percentage of alkali metal oxides ( Na 2 O plus K 2 O ) is second only to silica in its importance for chemically classifying volcanic rock. The silica and alkali metal oxide percentages are used to place volcanic rock on the TAS diagram , which is sufficient to immediately classify most volcanic rocks. Rocks in some fields, such as the trachyandesite field, are further classified by

2900-582: The Basin and Range Province of North America's Great Basin . The Owens Valley is a graben or rift valley , a section of land that has dropped down between two parallel faults , while the land on either side has risen. This has resulted in the flat floor and steep, towering walls of the present-day valley. With the Sierra Nevada on the west side and the Inyo Mountains and White Mountains on

3016-479: The IUGS , this is often impractical, and chemical classification is done instead using the TAS classification . Igneous rocks are classified according to mode of occurrence, texture, mineralogy, chemical composition, and the geometry of the igneous body. The classification of the many types of igneous rocks can provide important information about the conditions under which they formed. Two important variables used for

3132-747: The Mono Basin (the next basin to the north of the Owens Valley ). An extension to the aqueduct was built, which included such engineering feats as tunneling through the Mono Craters (an active volcanic field). By 1941, the extension was finished, and water in various creeks (such as Rush Creek ) were diverted into the aqueduct. To satisfy California water law, LADWP set up a fish hatchery on Hot Creek , near Mammoth Lakes, California . The diverted creeks had previously fed Mono Lake , an inland body of water with no outlet. Mono Lake served as

3248-640: The Owens River started being diverted to Los Angeles in 1913, precipitating conflict and eventual ruin of the valley's economy. By the 1920s, so much water was diverted from the Owens Valley that agriculture became difficult. This led to the farmers trying to destroy the aqueduct in 1924. Los Angeles prevailed and kept the water flowing. By 1926, Owens Lake at the bottom of Owens Valley was completely dry due to water diversion. The water needs of Los Angeles kept growing. In 1941, Los Angeles diverted water that previously fed Mono Lake , north of Owens Valley, into

3364-847: The San Joaquin River since 2009, won after 18 years of litigation, with increased releases from the Friant Dam east of Fresno. Democratic Senators Dianne Feinstein and Barbara Boxer proposed emergency drought legislation of $ 300 million aid, and to speed up environmental reviews of water projects, so state and federal officials have "operational flexibility" to move water south, from the delta to San Joaquin Valley farms. On February 14, 2014, President Barack Obama visited near Fresno and announced $ 170 million worth of initiatives, with $ 100 million for ranchers facing livestock losses and $ 60 million to help food banks. Obama joked about

3480-570: The United States gained control of California in 1848 , the first public land survey conducted by A.W. von Schmidt from 1855 to 1856 was an initial step in securing government control of the valley. Von Schmidt reported that the valley's soil was not good for agriculture except for the land near streams, and stated that the "Owens Valley [was] worthless to the White Man." In 1861, Samuel Bishop and other ranchers started to raise cattle on

3596-453: The convection of solid mantle, it will cool slightly as it expands in an adiabatic process , but the cooling is only about 0.3 °C per kilometre. Experimental studies of appropriate peridotite samples document that the solidus temperatures increase by 3 °C to 4 °C per kilometre. If the rock rises far enough, it will begin to melt. Melt droplets can coalesce into larger volumes and be intruded upwards. This process of melting from

Owens River - Misplaced Pages Continue

3712-484: The debt limit of Los Angeles, which allowed the financing of the aqueduct. The San Fernando land syndicate were a group of wealthy investors who bought up large tracts of land in the San Fernando Valley with secret inside information from Eaton. The syndicate included friends of Eaton, such as Harrison Gray Otis and Henry E. Huntington . This syndicate made substantial efforts to support passage of

3828-473: The 1640s and is derived either from French granit or Italian granito , meaning simply "granulate rock". The term rhyolite was introduced in 1860 by the German traveler and geologist Ferdinand von Richthofen The naming of new rock types accelerated in the 19th century and peaked in the early 20th century. Much of the early classification of igneous rocks was based on the geological age and occurrence of

3944-434: The 1960s. However, the concept of normative mineralogy has endured, and the work of Cross and his coinvestigators inspired a flurry of new classification schemes. Among these was the classification scheme of M.A. Peacock, which divided igneous rocks into four series: the alkalic, the alkali-calcic, the calc-alkali, and the calcic series. His definition of the alkali series, and the term calc-alkali, continue in use as part of

4060-570: The 20-mile-long (32 km) Owens River Gorge , emerging at the north end of the Owens Valley northwest of Bishop . In the area around Bishop, it is diverted through many ditches to irrigate the surrounding farming region. It flows south-southeast through the Owens Valley between the Sierra Nevada on the west and the White and Inyo Mountains on the east, past Big Pine . Approximately 14 miles (22.5 km) south-southeast of Big Pine, most of

4176-475: The 62 mi (100 km) lower Owens River in December 2006. In less than one year, the lower Owens River was teeming with fish, birds and other wildlife. California Water Wars The California Water Wars were a series of political conflicts between the city of Los Angeles and farmers and ranchers in the Owens Valley of Eastern California over water rights . As Los Angeles expanded during

4292-796: The Delta via state and federal water projects. Half a million acres of Central Valley farmland supposedly was in danger of going fallow due to drought. On 5 February 2014 the House passed a bill to increase flows from the Sacramento–San Joaquin River Delta to the Central Valley, the Sacramento-San Joaquin Valley Emergency Water Delivery Act (H.R. 3964; 113th Congress) . This would suspend the very recent efforts to restore

4408-520: The Earth's surface. Intrusive igneous rocks that form at depth within the crust are termed plutonic (or abyssal ) rocks and are usually coarse-grained. Intrusive igneous rocks that form near the surface are termed subvolcanic or hypabyssal rocks and they are usually much finer-grained, often resembling volcanic rock. Hypabyssal rocks are less common than plutonic or volcanic rocks and often form dikes, sills, laccoliths, lopoliths , or phacoliths . Extrusive igneous rock, also known as volcanic rock,

4524-627: The Interior Ethan A. Hitchcock , Bureau of Forests Commissioner Gifford Pinchot , and Director of the Geological Survey Charles D. Walcott . In this meeting, Roosevelt decided in favor of Los Angeles. Several authors, such as Rolle and Libecap, argue that Los Angeles paid an unfairly low price to the farmers of Owens Valley for their land. Gary Libecap of the University of California, Santa Barbara observed that

4640-671: The Inyo County Water Department from 2003 onward showed that impacts to the valley's groundwater-dependent vegetation, such as alkali meadows, continue. Likewise, Los Angeles did not re-water the lower Owens River by the June 2003 deadline. In December, 2003, LADWP settled a lawsuit brought by California Attorney General Bill Lockyer , the Owens Valley Committee, and the Sierra Club. Under

4756-419: The L.A. Water and Power Board, countered Mulholland's words from 1913 and said, " There it is ... take it back. " Nevertheless, groundwater pumping continues at a higher rate than the rate at which water recharges the aquifer, resulting in a long-term trend of desertification in the Owens Valley. By the 1930s, the water requirements for Los Angeles continued to increase. LADWP started buying water rights in

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4872-562: The Los Angeles Aqueduct. At the start of the 20th century, the northern part of the Owens Valley turned to raising fruit, poultry and dairy. Frederick Eaton and William Mulholland were two of the more visible principals in the California water wars. They were friends, having worked together in the private Los Angeles Water Company in the 1880s. In 1886, Eaton became City Engineer and Mulholland became superintendent of

4988-452: The Owens Valley in 1845. His party included Kit Carson , Edward Kern , and Richard Owens, the latter for whom the river, lake, and valley are named. Other well-known adventurers included Jedediah Smith and Joseph R. Walker , who also came into the area in the 1800s. Gradually, the river's surroundings were settled by farmers and ranchers. The valley never accumulated a very large population, but mining activities brought significant income to

5104-491: The Owens Valley to become a cattle rancher on the land he purchased. Eaton always denied that he acted in a deceptive manner. Mulholland misled Los Angeles public opinion by dramatically understating the amount of water locally available for Los Angeles's growth. Mulholland also misled residents of the Owens Valley: he indicated that Los Angeles would only use unused flows in the Owens Valley, while planning on using

5220-453: The Owens Valley, claiming that beaver are damming flows into their diversions of water to Los Angeles . This decision runs counter to an independent assessment commissioned by LADWP and the Inyo County Water Department in 1997, where it was recommended that beaver be maintained in reasonable populations and their dams left in place because "Although beaver activity has resulted in the removal of much willow and other shrub and woody vegetation and

5336-661: The Owens Valley, mostly in Lone Pine. Beaver was re-introduced to the Owens Valley by the California Department of Fish and Game in 1948 in Baker Creek, and has since spread throughout the Owens Valley. Although it is controversial whether beaver were once native to the Owens Valley, there is growing evidence that they were native to the eastern slope of the Sierra Nevada. In particular, the northern Paiute of Walker Lake , Honey Lake and Pyramid Lake have

5452-625: The Truckee River in 1833", which strongly suggests that he saw a beaver or beaver sign. Supporting this line of evidence, Tappe records in 1941 an eyewitness who said beaver were plentiful on the upper part of the Carson River and its tributaries in Alpine County until 1892 when they fell victim to heavy trapping. In 2011, the Los Angeles Department of Water and Power (LADWP) decided to trap beaver ( Castor canadensis ) out of

5568-612: The Water Company. In 1898, Eaton was elected mayor of Los Angeles and was instrumental in converting the Water Company to city control in 1902. When the company became the Los Angeles Water Department , Mulholland continued to be superintendent, due to his extensive knowledge of the water system. Eaton and Mulholland had a vision of a Los Angeles that would become far larger than the Los Angeles of

5684-476: The aqueduct. Mono Lake's ecosystem for migrating birds was threatened by dropping water levels. Between 1979 and 1994, David Gaines and the Mono Lake Committee engaged in litigation with Los Angeles. The litigation forced Los Angeles to stop diverting water from around Mono Lake, which has started to rise back to a level that can support its ecosystem. The Paiute natives were the inhabitants of

5800-450: The basic TAS classification include: In older terminology, silica oversaturated rocks were called silicic or acidic where the SiO 2 was greater than 66% and the family term quartzolite was applied to the most silicic. A normative feldspathoid classifies a rock as silica-undersaturated; an example is nephelinite . Magmas are further divided into three series: The alkaline series

5916-539: The bed of Owens Lake. The Owens River itself heads at an elevation of 7,291 feet (2,222 m). Few people inhabit the sparse, open grasslands and steep mountainsides of the watershed; the 2009 population of Mono County was about 12,927 while Inyo County had some 17,293 inhabitants. The largest city on the river is Bishop , with a population of just under 4,000. Other significant towns include Lone Pine (population 2,035), Big Pine (population 1,707), and Independence (population 669). The Owens River flows through part of

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6032-666: The benefit of all people. The litigation reached the California Supreme Court by 1983, which ruled in favor of the committee. Further litigation was initiated in 1984, which claimed that LADWP did not comply with the state fishery protection laws. Eventually, all of the litigation was adjudicated in 1994, by the California State Water Resources Control Board (SWRCB) . The SWRCB hearings lasted for 44 days and were conducted by Board Vice-chair Marc Del Piero acting as

6148-484: The bond issue that funded the aqueduct. These efforts are reported to have included the dumping of water from Los Angeles reservoirs into the sewers (thereby creating a false drought) and by publishing scare articles in the Los Angeles Times , which Otis published. Remi Nadeau , a historian and author, disputed that water was dumped from reservoirs, because the sewer system may not have been connected to

6264-568: The calc-alkaline magmas. Some island arcs have distributed volcanic series as can be seen in the Japanese island arc system where the volcanic rocks change from tholeiite—calc-alkaline—alkaline with increasing distance from the trench. Some igneous rock names date to before the modern era of geology. For example, basalt as a description of a particular composition of lava-derived rock dates to Georgius Agricola in 1546 in his work De Natura Fossilium . The word granite goes back at least to

6380-429: The chemical composition of an igneous rock was its most fundamental characteristic, it should be elevated to prime position. Geological occurrence, structure, mineralogical constitution—the hitherto accepted criteria for the discrimination of rock species—were relegated to the background. The completed rock analysis is first to be interpreted in terms of the rock-forming minerals which might be expected to be formed when

6496-625: The classification of igneous rocks are particle size, which largely depends on the cooling history, and the mineral composition of the rock. Feldspars , quartz or feldspathoids , olivines , pyroxenes , amphiboles , and micas are all important minerals in the formation of almost all igneous rocks, and they are basic to the classification of these rocks. All other minerals present are regarded as nonessential in almost all igneous rocks and are called accessory minerals . Types of igneous rocks with other essential minerals are very rare, but include carbonatites , which contain essential carbonates . In

6612-489: The closure left merchants and customers with little more than the small amount of money they had on hand. The brothers claimed that the fraud was done for the good of the Owens Valley against Los Angeles, and this excuse was generally believed to be true in Inyo County. The collapse of the bank wiped out the lifetime savings of many people, including payments gained from the sale of homes and ranches to Los Angeles. In

6728-600: The complexity of the project was comparable to the building of the Panama Canal . Water from the Owens River reached a reservoir in the San Fernando Valley on November 5, 1913. At a ceremony that day, Mulholland spoke his famous words about this engineering feat: "There it is. Take it." After the aqueduct was completed in 1913, the San Fernando investors demanded so much water from the Owens Valley that it started to transform from "The Switzerland of California" into

6844-591: The cooling and solidification of magma or lava . The magma can be derived from partial melts of existing rocks in either a planet 's mantle or crust . Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure , or a change in composition. Solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, or without crystallization to form natural glasses . Igneous rocks occur in

6960-487: The cooperative. After these water rights were secured, inflows to Owens Lake were heavily diverted, which caused the lake to dry up by 1924. By 1924, farmers and ranchers rebelled. A series of provocations by Mulholland were, in turn, followed by corresponding threats from local farmers, and the destruction of Los Angeles property. Finally, a group of armed ranchers seized the Alabama Gates and dynamited part of

7076-403: The dam would be breached, allowing the river to flow naturally again, while fish would be collected in the dried-up river channel. By then, there would be enough food stored to last the winter in which the cropland would lie fallow. In the nineteenth century, the Owens River was first seen by American explorers. One of the first explorers was John C. Fremont , who led a cartographic expedition to

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7192-400: The dams create favorable tule conditions and reduce fish spawning habitat, they also provide important fish rearing habitat, mesic meadows, and promote the growth of other riparian species. It is most likely that the physical removal of beaver dams will result in more adverse environmental impacts than environmental benefits." The acquisition of water rights for the Los Angeles Aqueduct under

7308-402: The different types of extrusive igneous rocks than between different types of intrusive igneous rocks. Generally, the mineral constituents of fine-grained extrusive igneous rocks can only be determined by examination of thin sections of the rock under a microscope , so only an approximate classification can usually be made in the field . Although classification by mineral makeup is preferred by

7424-467: The direction of William Mulholland was highly controversial and led to violence and sabotage by local residents in the 1920s. The diversion of water and the subsequent desiccation of Owens Lake remains highly controversial, and the restoration of the lake has been a long-time goal of the California environmentalist community. The lower Owens River and Owens Lake were left dry by the 1913 diversions, until lawsuits forced LADWP to start releasing water into

7540-546: The east, and the Death Valley Wash from the north. During this relatively short time, the Owens River became part of a vast interior drainage system that stretched east to west, covering over 8,000 square miles (21,000 km). During the runoff peak, water from this massive basin may have escaped to the Colorado River through a valley leading to the southeast. For thousands of years the Owens River valley

7656-489: The east, with the highest peaks of either range rising to over 14,000 feet (4,300 m) and the floor of the valley at a comparatively low 3,000 to 4,000 feet (910 to 1,220 m), the Owens River flows in one of the deepest valleys in the United States. Further to the north, the Owens River basin encompasses predominantly igneous rocks and vast remnants of past volcanic activity. The upper 30 miles (48 km) of

7772-486: The ecosystem of Mono Lake. This led to a 1977 report on the ecosystem of Mono Lake that highlighted dangers caused by the water diversion. In 1978, the Mono Lake Committee was formed to protect Mono Lake. The committee (and the National Audubon Society ) sued LADWP in 1979, arguing that the diversions violated the public trust doctrine , which states that navigable bodies of water must be managed for

7888-484: The extensive basalt magmatism of several large igneous provinces. Decompression melting occurs because of a decrease in pressure. The solidus temperatures of most rocks (the temperatures below which they are completely solid) increase with increasing pressure in the absence of water. Peridotite at depth in the Earth's mantle may be hotter than its solidus temperature at some shallower level. If such rock rises during

8004-606: The extreme southwestern Great Basin – the Long Valley and Owens Valley. The north to south drainage basin is in portions of Mono and Inyo counties and terminates in the now-dry Owens Lake. To the northwest of the valley is the Long Valley Caldera, which is only a fraction of the size of the Owens Valley. The Owens River enters Owens Valley from the northwest, while the Spring Valley Wash drains

8120-513: The face of the collapse of resistance and of the Owens Valley economy, the attacks on the aqueduct ceased. The City of Los Angeles sponsored a series of repair and maintenance programs for aqueduct facilities that stimulated some local employment, and the Los Angeles water employees were paid a month in advance to bring some relief. But it was impossible to prevent many businesses from closing their doors. The City of Los Angeles continued to purchase private land holdings and their water rights to meet

8236-493: The full water rights to fill the aquifer of the San Fernando Valley . By 1907, Eaton was busy acquiring key water rights and traveling to Washington to meet with advisers of Theodore Roosevelt to convince them that the water of the Owens River would do more good flowing through faucets in Los Angeles than it would if used on Owens Valley fields and orchards. The dispute over the Owens River water became

8352-486: The great majority of cases, the rock has a more typical mineral composition, with significant quartz, feldspars, or feldspathoids. Classification is based on the percentages of quartz, alkali feldspar, plagioclase, and feldspathoid out of the total fraction of the rock composed of these minerals, ignoring all other minerals present. These percentages place the rock somewhere on the QAPF diagram , which often immediately determines

8468-689: The impacts of groundwater pumping, Inyo County sued Los Angeles under the terms of the California Environmental Quality Act . Los Angeles did not stop pumping groundwater, but submitted a short EIR in 1976 and a second one in 1979, both of which were rejected as inadequate by the courts. In 1991, Inyo County and the city of Los Angeles signed the Inyo-Los Angeles Long Term Water Agreement, which required that groundwater pumping be managed to avoid significant impacts while providing

8584-567: The increasing demands. By 1928, Los Angeles owned 90 percent of the water in Owens Valley and agriculture interests in the region were effectively dead. In 1970, LADWP completed a second aqueduct . In 1972, the agency began to divert more surface water and pumped groundwater at the rate of several hundred thousand acre-feet a year (several cubic meters per second). Owens Valley springs and seeps dried and disappeared, and groundwater-dependent vegetation began to die. Because LADWP had never completed an Environmental Impact Report (EIR) addressing

8700-408: The land for farming and ranching. None of the sales were made under threat of eminent domain . The aqueduct was sold to the citizens of Los Angeles as vital to the growth of the city. Unknown to the public, the initial water would be used to irrigate the San Fernando Valley to the north, which was not at the time a part of the city. From a hydrological point of view, the San Fernando Valley

8816-433: The larger crystals, called phenocrysts, grow to considerable size before the main mass of the magma crystallizes as finer-grained, uniform material called groundmass. Grain size in igneous rocks results from cooling time so porphyritic rocks are created when the magma has two distinct phases of cooling. Igneous rocks are classified on the basis of texture and composition. Texture refers to the size, shape, and arrangement of

8932-426: The late 19th century, it began outgrowing its water supply. Fred Eaton , mayor of Los Angeles, promoted a plan to take water from Owens Valley to Los Angeles via an aqueduct . The aqueduct construction was overseen by William Mulholland and was finished in 1913. The water rights were acquired through political fighting and, as described by one author, "chicanery, subterfuge ... and a strategy of lies". Water from

9048-467: The lengthy and incendiary history of water politics in California, saying, "I'm not going to wade into this. I want to get out alive on Valentine's Day." The California water wars were among the subjects discussed in Cadillac Desert , a 1984 nonfiction book by Marc Reisner about land development and water policy in the western United States. The book was made into a four-part documentary of

9164-642: The luxuriant grasses that grew in the Owens Valley. The ranchers came into conflict with the Paiutes over land and water use, and most of the Paiutes were driven away from the valley by the U.S. Army in 1863 during the Owens Valley Indian War . Many settlers came to the area for the promise of riches from mining. The availability of water from the Owens River made farming and raising livestock attractive. The Homestead Act of 1862 gave pioneers five years to claim and take title of their land for

9280-399: The magma crystallizes, e.g., quartz feldspars, olivine , akermannite, Feldspathoids , magnetite , corundum , and so on, and the rocks are divided into groups strictly according to the relative proportion of these minerals to one another. This new classification scheme created a sensation, but was criticized for its lack of utility in fieldwork, and the classification scheme was abandoned by

9396-437: The majority of igneous rocks and are formed from magma that cools and solidifies within the crust of a planet. Bodies of intrusive rock are known as intrusions and are surrounded by pre-existing rock (called country rock ). The country rock is an excellent thermal insulator , so the magma cools slowly, and intrusive rocks are coarse-grained ( phaneritic ). The mineral grains in such rocks can generally be identified with

9512-457: The majority of minerals will be visible to the naked eye or at least using a hand lens, magnifying glass or microscope. Plutonic rocks also tend to be less texturally varied and less prone to showing distinctive structural fabrics. Textural terms can be used to differentiate different intrusive phases of large plutons, for instance porphyritic margins to large intrusive bodies, porphyry stocks and subvolcanic dikes . Mineralogical classification

9628-415: The mid-1890s, most of the land in the Owens Valley had been claimed. The large number of claims made by land speculators hindered the region's development because speculators would not participate in developing canals and ditches. Before the Los Angeles Aqueduct, most of the 200 miles (320 km) of canals and ditches that constituted the irrigation system in the Owens Valley were in the north, while

9744-697: The mineral grains or crystals of which the rock is composed. Texture is an important criterion for the naming of volcanic rocks. The texture of volcanic rocks, including the size, shape, orientation, and distribution of mineral grains and the intergrain relationships, will determine whether the rock is termed a tuff , a pyroclastic lava or a simple lava . However, the texture is only a subordinate part of classifying volcanic rocks, as most often there needs to be chemical information gleaned from rocks with extremely fine-grained groundmass or from airfall tuffs, which may be formed from volcanic ash. Textural criteria are less critical in classifying intrusive rocks where

9860-415: The naked eye are called phaneritic ; those with crystals too small to be seen are called aphanitic . Generally speaking, phaneritic implies an intrusive origin or plutonic, indicating slow cooling; aphanitic are extrusive or volcanic, indicating rapid cooling. An igneous rock with larger, clearly discernible crystals embedded in a finer-grained matrix is termed porphyry . Porphyritic texture develops when

9976-492: The naked eye. Intrusions can be classified according to the shape and size of the intrusive body and its relation to the bedding of the country rock into which it intrudes. Typical intrusive bodies are batholiths , stocks , laccoliths , sills and dikes . Common intrusive rocks are granite , gabbro , or diorite . The central cores of major mountain ranges consist of intrusive igneous rocks. When exposed by erosion, these cores (called batholiths ) may occupy huge areas of

10092-497: The new inhabitants of the area. Ore was shipped down the Owens River from the north, and also borax and silver from Death Valley to the east. Until 1924, Owens Lake was still so large that a steamboat ferry operated between its east and west sides, ferrying freight and passengers across in three hours, much less than the three days required to semi-circumnavigate the lake. In 1872, the Lone Pine earthquake killed 27 people in

10208-587: The north of the Caldera, extending to the Mono Lake area, lie the chain of Mono-Inyo Craters , which range in age from 400,000 to 500 years old. During the Pleistocene at the end of the last glacial period , melting glaciers in the Sierra Nevada and Inyo/White Mountains fed prodigious amounts of runoff into the Owens River, causing it to expand to many times its current size. The increased river volume caused Owens Lake to rise as well, eventually spilling out

10324-446: The northernmost part of the valley, extending a tiny portion of the basin into Nevada . The river flows mainly on the east side of the valley, because alluvial deposits from Sierra Nevada streams have forced the river channel in that direction. Vertical relief in the basin is immense – elevations range from 14,505 feet (4,421 m) at Mount Whitney , the highest peak in the continental United States , to 3,556 feet (1,084 m) on

10440-596: The pre-aqueduct flow to the river by court order, allowing the Owens River Gorge , the river bed in the valley, and Owens Lake to contain a small amount of water. The river rises in the Sierra Nevada in southwestern Mono County , approximately 15 miles (24.1 km) south of Mono Lake and 35 miles (56.3 km) east of Yosemite Valley . It flows southeast across the Long Valley Caldera , through Lake Crowley reservoir , then descends through

10556-455: The price that Los Angeles was willing to pay to other water sources per volume of water was far higher than what the farmers received. Farmers who resisted the pressure from Los Angeles until 1930 received the highest price for their land; most farmers sold their land from 1905 to 1925, and received less than Los Angeles was actually willing to pay. However, the sale of their land brought the farmers substantially more income than if they had kept

10672-441: The ratio of potassium to sodium (so that potassic trachyandesites are latites and sodic trachyandesites are benmoreites). Some of the more mafic fields are further subdivided or defined by normative mineralogy , in which an idealized mineral composition is calculated for the rock based on its chemical composition. For example, basanite is distinguished from tephrite by having a high normative olivine content. Other refinements to

10788-403: The release of dissolved gases—typically water vapour, but also carbon dioxide . Explosively erupted pyroclastic material is called tephra and includes tuff , agglomerate and ignimbrite . Fine volcanic ash is also erupted and forms ash tuff deposits, which can often cover vast areas. Because volcanic rocks are mostly fine-grained or glassy, it is much more difficult to distinguish between

10904-407: The remaining river is diverted into the Los Angeles Aqueduct , completed in 1913 to supply municipal, recreational and agricultural water to Los Angeles . The remaining river flows through the southern valley, flanked by the Los Angeles Aqueduct, past Lone Pine , entering the lake bed of predominantly dry Owens Lake at the southern end of Owens Valley. The river flows through two major valleys of

11020-526: The required 17.4 feet (5.3 m). Los Angeles made up for the lost water through state-funded conservation and recycling projects. In February 2014, after three consecutive years of below-normal rainfall, California faced its most severe drought emergency in decades with fish populations in the Sacramento–San Joaquin River Delta in unprecedented crisis due to the decades of large-scale water exports from Northern California to south of

11136-490: The reservoirs. The syndicate did unify the business community behind the aqueduct, and its purchases were public by the time the vote on the aqueduct was taken. From 1907 through 1913, Mulholland directed the building of the aqueduct. The 233-mile (375 km) Los Angeles Aqueduct , inaugurated in November 1913, required more than 2,000 workers and the digging of 164 tunnels. Mulholland's granddaughter has stated that

11252-414: The river run through the Long Valley Caldera , an enormous 20-mile (32 km)-wide crater formed by a volcanic eruption some 760,000 years ago. The eruption's resulting ash cloud covered much of the southwestern United States, including parts of ten U.S. states . Mammoth Mountain , to the southwest (more popularly known as a major ski area) also formed from eruptions related to the Long Valley Caldera. To

11368-473: The rock must be classified chemically. There are relatively few minerals that are important in the formation of common igneous rocks, because the magma from which the minerals crystallize is rich in only certain elements: silicon , oxygen , aluminium, sodium , potassium , calcium , iron, and magnesium . These are the elements that combine to form the silicate minerals , which account for over ninety percent of all igneous rocks. The chemistry of igneous rocks

11484-424: The rock type. In a few cases, such as the diorite-gabbro-anorthite field, additional mineralogical criteria must be applied to determine the final classification. Where the mineralogy of an volcanic rock can be determined, it is classified using the same procedure, but with a modified QAPF diagram whose fields correspond to volcanic rock types. When it is impractical to classify a volcanic rock by mineralogy,

11600-467: The rocks. However, in 1902, the American petrologists Charles Whitman Cross , Joseph P. Iddings , Louis V. Pirsson , and Henry Stephens Washington proposed that all existing classifications of igneous rocks should be discarded and replaced by a "quantitative" classification based on chemical analysis. They showed how vague, and often unscientific, much of the existing terminology was and argued that as

11716-427: The same name in 1997. The 1974 film Chinatown was inspired by the California water wars and features a fictionalized version of the conflict as a central plot element. Igneous rock Igneous rock ( igneous from Latin igneus  'fiery'), or magmatic rock , is one of the three main rock types , the others being sedimentary and metamorphic . Igneous rocks are formed through

11832-531: The sole Hearing Officer. In that ruling (SWRCB Decision 1631), the SWRCB established significant public trust protection and eco-system restoration standards, and LADWP was required to release water into Mono Lake to raise the lake level 17.4 feet (5.3 m) above the then-current level of 42.4 feet (12.9 m) below the 1941 level. As of 2022, the water level in Mono Lake has risen only 4.1 feet (1.2 m) of

11948-667: The south side of the valley into the Mojave Desert . Ancient, now-abandoned river channels suggest that the extended Owens River ran south to China Lake, then east into Searles Lake , north into the Panamint Valley (where it formed Panamint Lake), and finally east into Death Valley and the ancient Lake Manly . This great inland sea was also fed by the Mojave River from the south, the Amargosa River from

12064-469: The southern region of the valley was mostly inhabited by people raising livestock. The irrigation systems created by the ditch companies did not have adequate drainage and as a result oversaturated the soil to the point where crops could not be raised. The irrigation systems also significantly lowered the water level in the Owens Lake , a process that was intensified later by the diversion of water through

12180-404: The spring out of materials including boulders, dirt, reeds, grass, or other elements. The watercourse below the dam would then be desiccated, and the water led by canal to the irrigated plot of land, typically no more than a few square miles. Directly after the dam was closed and the river dried up, fish trapped on the dry riverbed would then be gathered and eaten. Before winter storms caused floods,

12296-565: The start of the 20th century. The limiting factor of Los Angeles's growth was water supply. "If you don't get the water, you won't need it," Mulholland famously remarked. Eaton and Mulholland realized that the Owens Valley had a large amount of runoff from the Sierra Nevada , and a gravity-fed aqueduct could deliver the Owens water to Los Angeles. At the start of the 20th century, the United States Bureau of Reclamation , at

12412-457: The system, letting water return to the Owens River. In August 1927, when the conflict was at its height, the Inyo County bank collapsed, which massively undermined valley resistance. An audit revealed that there were shortages in both cash in the vault and amounts shown on the books. The Watterson brothers were indicted for embezzlement, then tried and convicted on thirty-six counts. Since all local business had been transacted through their bank,

12528-513: The terms of the settlement, deadlines for the Lower Owens River Project were revised and LADWP was to return water to the lower Owens River by 2005. This deadline was missed, but on December 6, 2006, a ceremony was held at the same site where William Mulholland had ceremonially opened the aqueduct which had closed the flow through the Owens River, to restart it down the 62 miles (100 km) river. David Nahai , president of

12644-573: The time known as the United States Reclamation Service, was planning on building an irrigation system to help the farmers of the Owens Valley, which would block Los Angeles from diverting the water. From 1902 to 1905, Eaton and Mulholland used underhanded methods to obtain water rights and block the Bureau of Reclamation. The regional engineer of the Bureau, Joseph Lippincott, was a close associate of Eaton; Eaton

12760-413: The valley in the early 1800s, and used irrigation to grow crops. In 1833, Joseph Reddeford Walker led the first known expedition into the central California area that would later be called the Owens Valley . Walker saw that the valley's soil conditions were inferior to those on the other side of the Sierra Nevada range, and that runoff from the mountains was absorbed into the arid desert ground. After

12876-469: The valley once built dams across the Owens River (and possibly one of its major tributaries, Bishop Creek) to divert water into local canals. The switch from a hunter-gatherer to a settled, agricultural lifestyle is probably the result of the climate of the Owens Valley becoming drier some 1,000 years ago. Typically, the Native Americans built dams across the river or other tributary streams in

12992-586: The widely used Irvine-Barager classification, along with W.Q. Kennedy's tholeiitic series. By 1958, there were some 12 separate classification schemes and at least 1637 rock type names in use. In that year, Albert Streckeisen wrote a review article on igneous rock classification that ultimately led to the formation of the IUGG Subcommission of the Systematics of Igneous Rocks. By 1989 a single system of classification had been agreed upon, which

13108-507: Was a nominal agent for the Bureau through Lippincott, so Eaton had access to inside information about water rights and could recommend actions to the Bureau that would be beneficial to Los Angeles. In return, while Lippincott was employed by the Bureau, he also served as a paid private consultant to Eaton, advising Los Angeles on how to best obtain water rights. To help acquire water rights in 1905, Eaton made high offers to purchase land in Owens Valley. Eaton's eagerness aroused suspicion in

13224-467: Was further revised in 2005. The number of recommended rock names was reduced to 316. These included a number of new names promulgated by the Subcommission. The Earth's crust averages about 35 kilometres (22 mi) thick under the continents , but averages only some 7–10 kilometres (4.3–6.2 mi) beneath the oceans . The continental crust is composed primarily of sedimentary rocks resting on

13340-492: Was ideal: its aquifer could serve as free water storage without evaporation. One obstacle to the irrigation was the Los Angeles City Charter, which prohibited the sale, lease, or other use of the city's water without a two-thirds approval by the voters. This charter limitation would be avoided through the annexation of a large portion of the San Fernando Valley to the city. The annexation would also raise

13456-461: Was inhabited by the seminomadic Owens Valley Northern Paiute and the Shoshone tribes of Native Americans . The indigenous name for the river was Wakopee , while they called Owens Lake Pacheta . In the upper Owens Valley lie traces of some of California's first irrigation systems, created by Paiute groups to water small patches of crops. It is believed that native people in the upper portion of

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