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Diamond Valley Lake
Diamond Valley Lake is a man-made off-stream reservoir located near Hemet, California, United States. It is one of the largest reservoirs in Southern California and also one of the newest. With a capacity of , the lake nearly doubled the area's surface water storage capacity and provides additional water supplies for drought, peak summer, and emergency needs. The Metropolitan Water District of Southern California (MWD) began the $1.9 billion construction project in 1995. Filling of the lake, by way of the Colorado River Aqueduct, began in 1999 and was completed in 2003. The lake is currently served by the Inland Feeder. The lake features three earth fill dams, two located on either side of the valley and one on the north rim. Construction of the dams utilized nearby materials, and was one of the largest earthworks projects in the United States. Excavation of core materials for the dams resulted in many paleontological finds, all of which are displayed at the Western Science Cent ...
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Riverside County, California
Riverside County is a County (United States), county located in the southern California, southern portion of the U.S. state of California. As of the 2020 United States Census, 2020 census, the population was 2,418,185, making it the fourth-most populous county in California and the List of the most populous counties in the United States, 10th-most populous in the United States. The name was derived from the city of Riverside, California, Riverside, which is the county seat. Riverside County is included in the Riverside-San Bernardino, California, San Bernardino-Ontario, California, Ontario Metropolitan Statistical Area, also known as the Inland Empire. The county is also included in the Los Angeles-Long Beach, California, Long Beach Greater Los Angeles Area, Combined Statistical Area. Roughly rectangular, Riverside County covers in Southern California, spanning from the greater Los Angeles area to the Arizona border. Geographically, the county is mostly desert in the central a ...
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Earthworks (engineering)
Earthworks are engineering works created through the processing of parts of the earth's surface involving quantities of soil or unformed rock. Shoring structures An incomplete list of possible temporary or permanent geotechnical shoring structures that may be designed and utilised as part of earthworks: *Mechanically stabilized earth *Earth anchor * Cliff stabilization *Grout curtain *Retaining wall *Slurry wall *Soil nailing *Tieback (geotechnical) *Trench shoring * Caisson *Dam *Gabion *Ground freezing Gallery File:Mechanically stabilized earth diagram.gif, Mechanically stabilized earth File:GroutCurtain.gif, Grout curtain File:Retaining Wall Type Function.jpg, Retaining wall types File:Soil Nail.jpg, Soil nailing File:FEMA - 6044 - Photograph by Larry Lerner taken on 03-15-2002 in New York.jpg, Tieback File:Sbh s600.JPG, Trench shoring File:Caisson Schematic.svg, Caisson File:Vyrnwy dam.JPG, Dam File:Gabion 040.jpg, Gabions File:Cross section of a ground freezing pipe as u ...
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Hydroelectricity
Hydroelectricity, or hydroelectric power, is Electricity generation, electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other Renewable energy, renewable sources combined and also more than nuclear power. Hydropower can provide large amounts of Low-carbon power, low-carbon electricity on demand, making it a key element for creating secure and clean electricity supply systems. A hydroelectric power station that has a dam and reservoir is a flexible source, since the amount of electricity produced can be increased or decreased in seconds or minutes in response to varying electricity demand. Once a hydroelectric complex is constructed, it produces no direct waste, and almost always emits considerably less greenhouse gas than fossil fuel-powered energy plants.
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Schist
Schist ( ) is a medium-grained metamorphic rock showing pronounced schistosity. This means that the rock is composed of mineral grains easily seen with a low-power hand lens, oriented in such a way that the rock is easily split into thin flakes or plates. This texture (geology), texture reflects a high content of platy minerals, such as micas, talc, chlorite group, chlorite, or graphite. These are often interleaved with more granular minerals, such as feldspar or quartz. Schist typically forms during regional metamorphism accompanying the process of mountain building (orogeny) and usually reflects a medium Metamorphism#Metamorphic grades, grade of metamorphism. Schist can form from many different kinds of rocks, including sedimentary rocks such as mudstones and igneous rocks such as tuffs. Schist metamorphosed from mudstone is particularly common and is often very rich in mica (a ''mica schist''). Where the type of the original rock (the protolith) is discernible, the schist is us ...
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Caterpillar 789
The Caterpillar 789 dump truck is a model of haul trucks, typically used in open pit mining, manufactured by Caterpillar Inc. The 789 has a capacity of 177 tonnes, and its engine can produce 1770 horsepower. While some competing products use hybrid drive, the Caterpillar 789 has an entirely mechanical drive-train. The first Caterpillar 789 trucks were introduced in 1986. The vehicle's controls are designed to work much like those of an ordinary truck. However, they have multiple mechanisms for the driver to slow or stop the vehicle. Next to the traditional brake pedal Car controls are the components in automobiles and other powered road vehicles, such as trucks and buses, used for driving and parking. While controls like steering wheels and pedals have existed since the invention of cars, other controls have ... there is a second foot pedal to activate a secondary braking system. There is a lever to the right of the steering wheel, called the "retarding brake", used for ...
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Kiewit Corporation
Kiewit Corporation is an American privately held construction company based in Omaha, Nebraska founded in 1884. In 2021, it was ranked 243rd on the Fortune 500. Privately held, it is one of the largest construction and engineering organizations in North America. It is an employee-owned company. History The company was founded in 1884 as Kiewit Brothers Masonry Contractors by Peter and Andrew Kiewit, who were of Dutch descent. Their father, John Kiewit, emigrated from The Hague in 1857, where he learned the trade of brickmaking. John Kiewit established a brickyard in Omaha, Nebraska where his sons worked and learned the skills for their masonry business. Early projects included the seven-story Lincoln Hotel in Lincoln as stonemasons and the Bekins warehouse as general contractor. It is an employee-owned company. The original brothers dissolved their partnership in 1904 and the founding Peter Kiewit continued as a sole proprietorship. In 1912, two of his sons, Ralph and George K ...
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Soil Liquefaction
Soil liquefaction occurs when a cohesionless saturated or partially saturated soil substantially loses strength and stiffness in response to an applied stress such as shaking during an earthquake or other sudden change in stress condition, in which material that is ordinarily a solid behaves like a liquid. In soil mechanics, the term "liquefied" was first used by Allen Hazen in reference to the 1918 failure of the Calaveras Dam in California. He described the mechanism of flow liquefaction of the embankment dam as: The phenomenon is most often observed in saturated, loose (low density or uncompacted), sandy soils. This is because a loose sand has a tendency to compress when a load is applied. Dense sands, by contrast, tend to expand in volume or 'dilate'. If the soil is saturated by water, a condition that often exists when the soil is below the water table or sea level, then water fills the gaps between soil grains ('pore spaces'). In response to soil compressing, the po ...
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Phyllite
Phyllite ( ) is a type of foliated metamorphic rock created from slate that is further metamorphosed so that very fine grained white mica achieves a preferred orientation.Stephen Marshak ''Essentials of Geology'', 3rd ed. It is primarily composed of quartz, sericite mica, and chlorite. Phyllite has fine-grained mica flakes, whereas slate has extremely fine mica flakes, and schist has large mica flakes, all mica flakes of which have achieved a preferred orientation. Among foliated metamorphic rocks, it represents a gradation in the degree of metamorphism between slate and schist. The minute crystals of graphite, sericite, or chlorite, or the translucent fine-grained white mica, impart a silky, sometimes golden sheen to the surfaces of cleavage, called "phyllitic luster". The word comes from the Greek ''phyllon'', meaning "leaf". The protolith (or parent rock) for phyllite is shale or pelite, or slate, which in turn came from a shale protolith. Its constituent platy minerals ...
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Quartzite
Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of hematite. Other colors, such as yellow, green, blue and orange, are due to other minerals. The term ''quartzite'' is also sometimes used for very hard but unmetamorphosed sandstones that are composed of quartz grains thoroughly cemented with additional quartz. Such sedimentary rock has come to be described as orthoquartzite to distinguish it from metamorphic quartzite, which is sometimes called metaquartzite to emphasize its metamorphic origins. Quartzite is very resistant to chemical weathering and often forms ridges and resistant hilltops. The nearly pure silica conte ...
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San Andreas Fault
The San Andreas Fault is a continental transform fault that extends roughly through California. It forms the tectonics, tectonic boundary between the Pacific Plate and the North American Plate, and its motion is Fault (geology)#Strike-slip faults, right-lateral strike-slip (horizontal). The fault divides into three segments, each with different characteristics and a different degree of earthquake risk. The slip rate along the fault ranges from /yr. It was formed by a transform boundary. The fault was identified in 1895 by Professor Andrew Lawson of University of California, Berkeley, UC Berkeley, who discovered the northern zone. It is often described as having been named after San Andreas Lake, a small body of water that was formed in a valley between the two plates. However, according to some of his reports from 1895 and 1908, Lawson actually named it after the surrounding San Andreas Valley. Following the 1906 San Francisco earthquake, Lawson concluded that the fault extende ...
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