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50-459: The dam and reservoir rest on a wide plain of shale where the James River cut a canyon up to 1 mile (1.6 km) wide and 100 feet (30 m) deep. The shale (called Pierre Shale) has a dark gray, bedded appearance, and is mostly claystone or siltstone . The valley also contains many traces of alluvium , mainly deposited during the last ice age when the area was heavily glaciated . The dam

100-414: A hard, fissile, metamorphic rock known as slate . With continued increase in metamorphic grade the sequence is phyllite , then schist and finally gneiss . Shale is the most common source rock for hydrocarbons ( natural gas and petroleum ). The lack of coarse sediments in most shale beds reflects the absence of strong currents in the waters of the depositional basin. These might have oxygenated

150-538: A major Reclamation Bureau dam led to subsequent strengthening of its dam-safety program to avoid similar problems. Even so, the failure of Teton Dam, the environmental movement, and the announcement of President Carter 's "hit list" on water projects profoundly affected the direction of Reclamation's programs and activities. Reclamation operates about 180 projects in the 17 western states. The total Reclamation investment for completed project facilities in September 1992

200-401: A normal surface area of 2,095 acres (3.273 sq mi). Its maximum capacity is 230,000 acre-feet (280,000,000 m) and maximum surface area is over 13,250 acres (20.70 sq mi). The Jamestown Dam's primary purpose is flood control, and has prevented approximately $ 36 million in flood-related damages. When it was constructed, certain deficiencies were noted in the foundations for

250-1201: Is accompanied by telogenesis , the third and final stage of diagenesis. As erosion reduces the depth of burial, renewed exposure to meteoric water produces additional changes to the shale, such as dissolution of some of the cement to produce secondary porosity . Pyrite may be oxidized to produce gypsum . Black shales are dark, as a result of being especially rich in unoxidized carbon . Common in some Paleozoic and Mesozoic strata , black shales were deposited in anoxic , reducing environments, such as in stagnant water columns. Some black shales contain abundant heavy metals such as molybdenum , uranium , vanadium , and zinc . The enriched values are of controversial origin, having been alternatively attributed to input from hydrothermal fluids during or after sedimentation or to slow accumulation from sea water over long periods of sedimentation. Fossils , animal tracks or burrows and even raindrop impressions are sometimes preserved on shale bedding surfaces. Shales may also contain concretions consisting of pyrite, apatite , or various carbonate minerals. Shales that are subject to heat and pressure of metamorphism alter into

300-420: Is characterized by its tendency to split into thin layers ( laminae ) less than one centimeter in thickness. This property is called fissility . Shale is the most common sedimentary rock. The term shale is sometimes applied more broadly, as essentially a synonym for mudrock , rather than in the narrower sense of clay-rich fissile mudrock. Shale typically exhibits varying degrees of fissility. Because of

350-638: Is composed of about 58% clay minerals, 28% quartz, 6% feldspar , 5% carbonate minerals, and 2% iron oxides . Most of the quartz is detrital (part of the original sediments that formed the shale) rather than authigenic (crystallized within the shale after deposition). Shales and other mudrocks contain roughly 95 percent of the organic matter in all sedimentary rocks. However, this amounts to less than one percent by mass in an average shale. Black shales, which form in anoxic conditions, contain reduced free carbon along with ferrous iron (Fe ) and sulfur (S ). Amorphous iron sulfide , along with carbon, produce

400-430: Is evidence that shale acts as a semipermeable medium, allowing water to pass through while retaining dissolved salts. The fine particles that compose shale can remain suspended in water long after the larger particles of sand have been deposited. As a result, shales are typically deposited in very slow moving water and are often found in lakes and lagoonal deposits, in river deltas , on floodplains and offshore below

450-455: Is more likely to form nonfissile mudstone than shale. On the other hand, black shales often have very pronounced fissility ( paper shales ) due to binding of hydrocarbon molecules to the faces of the clay particles, which weakens the binding between particles. Lithification follows closely on compaction, as increased temperatures at depth hasten deposition of cement that binds the grains together. Pressure solution contributes to cementing, as

500-452: Is reduced. In addition to this physical compaction, chemical compaction may take place via pressure solution . Points of contact between grains are under the greatest strain, and the strained mineral is more soluble than the rest of the grain. As a result, the contact points are dissolved away, allowing the grains to come into closer contact. It is during compaction that shale develops its fissility, likely through mechanical compaction of

550-692: Is to "manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public". In redirecting its programs and responsibilities, Reclamation substantially reduced its staff levels and budgets but remains a significant federal agency in the West. On October 1, 2017, the Hoover Dam Police Department was closed and the National Park Service took over law enforcement duties for

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600-399: The U.S. Gulf Coast . As sediments continue to accumulate, the older, more deeply buried sediments begin to undergo diagenesis . This mostly consists of compaction and lithification of the clay and silt particles. Early stages of diagenesis, described as eogenesis , take place at shallow depths (a few tens of meters) and are characterized by bioturbation and mineralogical changes in

650-416: The spillway following in early June. This wide trench served to remove as much unstable material from the foundation as possible. This material was determined to be unsuitable for construction of the dam, and eventually discarded. Placement of concrete commenced in late June. Embankment construction began in late July. The upper portion of the upstream slope of the dam was covered with a layer of riprap , and

700-651: The wave base . Thick deposits of shale are found near ancient continental margins and foreland basins . Some of the most widespread shale formations were deposited by epicontinental seas . Black shales are common in Cretaceous strata on the margins of the Atlantic Ocean , where they were deposited in fault -bounded silled basins associated with the opening of the Atlantic during the breakup of Pangaea . These basins were anoxic, in part because of restricted circulation in

750-486: The 1960s and earlier drew to an end. Reclamation wrote that "The arid West essentially has been reclaimed. The major rivers have been harnessed and facilities are in place or are being completed to meet the most pressing current water demands and those of the immediate future". Emphasis in Reclamation programs shifted from construction to operation and maintenance of existing facilities. Reclamation's redefined official mission

800-887: The Department of the Interior. Frederick Haynes Newell was appointed the first director of the new bureau. Beginning with the third person to take over the direction of Reclamation in 1923, David W. Davis, the title was changed from Director to Commissioner. In the early years, many projects encountered problems: lands or soils included in projects were unsuitable for irrigation ; land speculation sometimes resulted in poor settlement patterns; proposed repayment schedules could not be met by irrigators who had high land-preparation and facilities-construction costs; settlers were inexperienced in irrigation farming; waterlogging of irrigable lands required expensive drainage projects; and projects were built in areas which could only grow low-value crops. In 1923

850-540: The Hardie-Tynes Manufacturing Company of Birmingham , Alabama , at a cost of $ 72,995. This contract was awarded on March 10, 1952, and the final shipment of the gates was made during February 1953. Construction began in April 1952. Excavation for the outlet works began the construction process, with excavation for the 215-foot (66 m) wide foundation trench beginning in mid-May and excavation for

900-516: The Hoover Dam. The Hoover Dam Police Department existed for more than 80 years. Reclamation commissioners that have had a strong impact and molding of the Bureau have included Elwood Mead , Michael W. Straus , and Floyd Dominy , with the latter two being public-power boosters who ran the Bureau during its heyday. Mead guided the bureau during the development, planning, and construction of the Hoover Dam,

950-524: The Interior , which oversees water resource management, specifically as it applies to the oversight and operation of the diversion, delivery, and storage projects that it has built throughout the western United States for irrigation , water supply , and attendant hydroelectric power generation . It is currently the U.S.'s largest wholesaler of water, bringing water to more than 31 million people, and providing one in five Western farmers with irrigation water for 10 million acres of farmland, which produce 60% of

1000-629: The James River has cut a valley 1,000 to 4,000 feet wide and 50 to 100 feet deep, which forms the reservoir. The overburden of the reservoir area consists of three types: The bedrock is Pierre Shale which is normally hard, dark gray, thinly bedded and highly jointed claystone or siltstone. Shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g., kaolin , Al 2 Si 2 O 5 ( OH ) 4 ) and tiny fragments ( silt -sized particles) of other minerals, especially quartz and calcite . Shale

1050-608: The United States Bureau of Reclamation. She was confirmed by the United States Senate on November 16, 2017. Burman is the first woman to ever lead the Bureau of Reclamation. David Murillo was serving as the acting commissioner of the bureau. Burman resigned on January 20 after the inauguration of the Biden Administration . The current Commissioner is Camille Calimlim Touton , the first Filipino American to head

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1100-585: The United States' first multiple-purpose dam. John W. Keys , the 16th Commissioner of the Bureau of Reclamation who served from July 2001 to April 2006, was killed two years after his retirement on May 30, 2008, when the airplane he was piloting crashed in Canyonlands National Park , Utah . On June 26, 2017, President Donald Trump nominated Brenda Burman to serve as the Commissioner of

1150-542: The agency was renamed the "Bureau of Reclamation". In 1924, however, in the face of increasing settler unrest and financial woes, the "Fact Finder's Report" spotlighted major problematic issues; the Fact Finders Act in late 1924 sought to resolve some of these problems. In 1928 Congress authorized the Boulder Canyon ( Hoover Dam ) Project, and large appropriations began, for the first time, to flow to Reclamation from

1200-421: The black coloration. Because amorphous iron sulfide gradually converts to pyrite , which is not an important pigment, young shales may be quite dark from their iron sulfide content, in spite of a modest carbon content (less than 1%), while a black color in an ancient shale indicates a high carbon content. Most shales are marine in origin, and the groundwater in shale formations is often highly saline . There

1250-506: The clumps of clay particles produced by flocculation vary in size from a few tens of microns to over 700 microns in diameter. The floccules start out water-rich, but much of the water is expelled from the floccules as the clay minerals bind more tightly together over time (a process called syneresis ). Clay pelletization by organisms that filter feed is important where flocculation is inhibited. Filter feeders produce an estimated 12 metric tons of clay pellets per square kilometer per year along

1300-408: The color of the rock. Red, brown and green colors are indicative of ferric oxide ( hematite – reds), iron hydroxide ( goethite – browns and limonite – yellow), or micaceous minerals ( chlorite , biotite and illite – greens). The color shifts from reddish to greenish as iron in the oxidized ( ferric ) state is converted to iron in the reduced ( ferrous ) state. Black shale results from

1350-484: The context of underground coal mining , shale was frequently referred to as slate well into the 20th century. Black shale associated with coal seams is called black metal. [REDACTED] Media related to Shale at Wikimedia Commons Bureau of Reclamation The Bureau of Reclamation , formerly the United States Reclamation Service , is a federal agency under the U.S. Department of

1400-543: The crest, the height is 110 feet (34 m). Its maximum thickness is 730 feet (220 m) from upstream toe to downstream toe. The dam embankment contains 8,667,000 cubic feet (245,400 m) of material, primarily dirt, rock, gravel and riprap . The dam's typical release rate is 1,400 cubic feet per second (40 m/s). The outlet works are controlled by four identical high-pressure gates, 5 feet by 6 feet (1.5 by 1.8 m) in size. Two are for normal use and two are for emergency releases. The maximum capacity of

1450-468: The dam. When the reservoir is at normal levels, the failure risk is small, but as the water level rises, the potential for collapse increases. Floods in May 1969 caused the reservoir to rise to its record level, over 105,000 acre-feet (130,000,000 m), causing leakage of the dam. This level was not even half the reservoir's maximum capacity of 230,000 acre-feet (280,000,000 m). In 1993 and 1995, floods caused

1500-459: The general funds of the United States. The authorization came only after a hard-fought debate about the pros and cons of public power versus private power. The heyday of Reclamation construction of water facilities occurred during the Depression and the 35 years after World War II . From 1941 to 1947, Civilian Public Service labor was used to carry on projects otherwise interrupted by

1550-600: The greatest migratory waterfowl flyways in North Dakota." It is stocked with fish by the North Dakota Game and Fish Department . Common fish species in the reservoir include pike , walleye , crappie , bluegill , smallmouth bass , muskie and bullhead . The Bureau of Reclamation details the geology of the reservoir area: The reservoir area is a gently rolling plain with a surface blanket of glacial till over-lying thin-bedded, highly jointed Pierre Shale. In this plain

Jamestown Dam - Misplaced Pages Continue

1600-466: The lake to rise to within 1 foot (0.3 m) of the 1969 level. An inspection by the Bureau of Reclamation 's Dam Safety Department revealed that the dam could potentially fail if the deficiencies were not corrected. As a result, eight relief wells (wells that drain a pervious stratum) were installed in the dam in 1995, and a heavy gravel filter blanket to prevent erosion of embankment materials during seepage

1650-417: The lower section was protected by a layer of gravel. By the end of 1952, the construction work was approximately 67% complete. Construction continued at a rapid pace after the beginning of the 1953 season. The upstream conduits for the outlet works were completed in April, and the four high pressure gates were installed beginning April 1. These and the spillway were all complete by August 31, and

1700-463: The main embankment was finished by September 11. On September 18, the final concrete placement occurred, and on September 20, 1953, the dam was completed under the primary contract, 251 days ahead of schedule. The Jamestown Dam is 1,418 feet (432 m) long at the crest and 85 feet (26 m) above the streambed of the James River . Measured from the deepest point of excavation to

1750-592: The mineral dissolved from strained contact points is redeposited in the unstrained pore spaces. The clay minerals may be altered as well. For example, smectite is altered to illite at temperatures of about 55 to 200 °C (130 to 390 °F), releasing water in the process. Other alteration reactions include the alteration of smectite to chlorite and of kaolinite to illite at temperatures between 120 and 150 °C (250 and 300 °F). Because of these reactions, illite composes 80% of Precambrian shales, versus about 25% of young shales. Unroofing of buried shale

1800-433: The narrow Atlantic, and in part because the very warm Cretaceous seas lacked the circulation of cold bottom water that oxygenates the deep oceans today. Most clay must be deposited as aggregates and floccules, since the settling rate of individual clay particles is extremely slow. Flocculation is very rapid once the clay encounters highly saline sea water. Whereas individual clay particles are less than 4 microns in size,

1850-625: The nation's vegetables and 25% of its fruits and nuts. The Bureau is also the second largest producer of hydroelectric power in the western U.S. On June 17, 1902, in accordance with the Reclamation Act , Secretary of the Interior Ethan Allen Hitchcock established the U.S. Reclamation Service within the U.S. Geological Survey (USGS). The new Reclamation Service studied potential water development projects in each western state with federal lands. Revenue from sale of federal lands

1900-415: The original open framework of clay particles. The particles become strongly oriented into parallel layers that give the shale its distinctive fabric. Fissility likely develops early in the compaction process, at relatively shallow depth, since fissility does not seem to vary with depth in thick formations. Kaolinite flakes have less tendency to align in parallel layers than other clays, so kaolinite-rich clay

1950-549: The outlet works is 2,990 cubic feet (85 m) per second, or 747.5 cubic feet (21.17 m) per second per gate. The dam also has an emergency inverted-bell spillway , capable of handling 2,930 cubic feet (83 m) per second. The total release capacity of the dam is 5,920 cubic feet (168 m) per second. The outlet works are designed to allow for possible future installation of hydroelectric generators and future municipal water supply. The Jamestown Reservoir typically holds 30,000 acre-feet (37,000,000 m) of water, with

2000-631: The parallel orientation of clay mineral flakes in shale, it breaks into thin layers, often splintery and usually parallel to the otherwise indistinguishable bedding planes . Non-fissile rocks of similar composition and particle size (less than 0.0625 mm) are described as mudstones (1/3 to 2/3 silt particles) or claystones (less than 1/3 silt). Rocks with similar particle sizes but with less clay (greater than 2/3 silt) and therefore grittier are siltstones . Shales are typically gray in color and are composed of clay minerals and quartz grains. The addition of variable amounts of minor constituents alters

2050-817: The presence of greater than one percent carbonaceous material and indicates a reducing environment. Pale blue to blue-green shales typically are rich in carbonate minerals . Clays are the major constituent of shales and other mudrocks. The clay minerals represented are largely kaolinite , montmorillonite and illite. Clay minerals of Late Tertiary mudstones are expandable smectites , whereas in older rocks (especially in mid-to early Paleozoic shales) illites predominate. The transformation of smectite to illite produces silica , sodium , calcium , magnesium , iron and water. These released elements form authigenic quartz , chert , calcite , dolomite , ankerite , hematite and albite , all trace to minor (except quartz) minerals found in shales and other mudrocks. A typical shale

Jamestown Dam - Misplaced Pages Continue

2100-490: The required excavations to stabilize the dam would have been over 120 feet (40 m) to solid bedrock . Bids for dam construction were submitted by several companies in early 1952. A bid of $ 1,868,862 was offered by the C.F. Lytle Company of Sioux City , Iowa . This bid was accepted, and the contract was awarded on March 25, 1952 with the notice to proceed received on March 31. The outlet works , which consist of four high-pressure floodgates , were provided by

2150-444: The richest source rocks may contain as much as 40% organic matter. The organic matter in shale is converted over time from the original proteins, polysaccharides , lipids , and other organic molecules to kerogen , which at the higher temperatures found at greater depths of burial is further converted to graphite and petroleum. Before the mid-19th century, the terms slate , shale and schist were not sharply distinguished. In

2200-433: The sediments, with only slight compaction. Pyrite may be formed in anoxic mud at this stage of diagenesis. Deeper burial is accompanied by mesogenesis , during which most of the compaction and lithification takes place. As the sediments come under increasing pressure from overlying sediments, sediment grains move into more compact arrangements, ductile grains (such as clay mineral grains) are deformed, and pore space

2250-451: The war effort. The last major authorization for construction projects occurred in the late 1960s, while a parallel evolution and development of the American environmental movement began to result in strong opposition to water development projects. Even the 1976 failure of Teton Dam as it filled for the first time did not diminish Reclamation's strong international reputation in water development circles. However, this first and only failure of

2300-414: The waters and destroyed organic matter before it could accumulate. The absence of carbonate rock in shale beds reflects the absence of organisms that might have secreted carbonate skeletons, also likely due to an anoxic environment. As a result, about 95% of organic matter in sedimentary rocks is found in shales and other mudrocks. Individual shale beds typically have an organic matter content of about 1%, but

2350-641: Was about $ 11 billion. Reclamation projects provide agricultural, household, and industrial water to about one‑third of the population of the American West. About 5% of the land area of the West is irrigated, and Reclamation provides water to about one-fifth of that area, some 9,120,000 acres (37,000 km ) in 1992. Reclamation is a major American generator of electricity . As of 2007 , Reclamation had 58 power plants on‑line and generated 125,000 GJ of electricity. From 1988 to 1994, Reclamation underwent major reorganization as construction on projects authorized in

2400-479: Was constructed in the spring of 1996. Besides flood control, the 8-mile (13 km) long, 2,095-acre (3.273 sq mi) Jamestown Reservoir was also created for the secondary purpose of recreation, which mainly involves camping , boating , fishing , and birding managed by the Stutsman County Park Board. The lake has approximately 45 miles (72 km) of shoreline and is referred to as "one of

2450-415: Was proposed in 1951. The site selected offered the required storage with the smallest dam and with close access to embankment materials; however, the underlying rock and soil was both unstable and pervious. The problems were considered minor because the extended storage need of the reservoir only consisted of the lower 30 feet (9.1 m) of the reservoir. If this had not compensated for the pervious material,

2500-703: Was the initial source of the program's funding. Because Texas had no federal lands, it did not become a Reclamation state until 1906, when Congress passed a law including it in the provisions of the Reclamation Act. From 1902 to 1907, Reclamation began about 30 projects in Western states. Then, in 1907, the Secretary of the Interior separated the Reclamation Service from the USGS and created an independent bureau within

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