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Grand Coulee
Grand Coulee is an ancient river bed in the U.S. state of Washington. This National Natural Landmark stretches for about 60 miles (100 km) southwest from Grand Coulee Dam to Soap Lake, being bisected by Dry Falls into the Upper and Lower Grand Coulee. Geological history Grand Coulee is a large coulee on the Columbia River Plateau. This area has underlying granite bedrock, formed deep in the Earth's crust 40 to 60 million years ago. The land periodically uplifted and subsided over millions of years giving rise to some small mountains and, eventually, an inland sea. From about 10 to 18 million years ago, a series of volcanic eruptions from the Grand Ronde Rift near the Idaho/Oregon/Washington/Montana border began to fill the inland sea with lava. In some places the volcanic basalt is thick. In other areas granite from the earlier mountains is still exposed. Starting about two million years ago, during the Pleistocene epoch, glaciation took place in the area. Large part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dry Falls
Dry Falls is a scalloped precipice with four major alcoves, in central Washington scablands. This cataract complex is on the opposite side of the Upper Grand Coulee from the Columbia River, and at the head of the Lower Grand Coulee, northern end of Lenore Canyon. According to the current geological model, catastrophic flooding channeled water at 65 miles per hour (105 kph) through the Upper Grand Coulee and over this rock face at the end of the last glaciation. It is estimated that the falls were five times the width of Niagara Falls, with ten times the flow of all the current rivers in the world combined. Nearly twenty thousand years ago, as glaciers moved south through North America, an ice sheet dammed the Clark Fork River near Sandpoint, Idaho. Consequently, a significant portion of western Montana flooded, forming the gigantic Lake Missoula. About the same time, Glacial Lake Columbia was formed on the ice-dammed Columbia River behind the Okanogan lobe of the Cordil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clark Fork (river)
The Clark Fork, or the Clark Fork of the Columbia River, is a river in the U.S. states of Montana and Idaho, approximately long. The largest river by volume in Montana, it drains an extensive region of the Rocky Mountains in western Montana and northern Idaho in the watershed of the Columbia River. The river flows northwest through a long valley at the base of the Cabinet Mountains and empties into Lake Pend Oreille in the Idaho Panhandle. The Pend Oreille River in Idaho, Washington, and British Columbia, Canada which drains the lake to the Columbia in Washington, is sometimes included as part of the Clark Fork, giving it a total length of , with a drainage area of . In its upper in Montana near Butte, it is known as Silver Bow Creek. Interstate 90 follows much of the upper course of the river from Butte to Saint Regis. The highest point within the river's watershed is Mount Evans at in Deer Lodge County, Montana along the Continental Divide. The Clark Fork is a Class I ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columbia River Basalt Group
The Columbia River Basalt Group is the youngest, smallest and one of the best-preserved continental flood basalt province on Earth, covering over mainly eastern Oregon and Washington, western Idaho, and part of northern Nevada. The basalt group includes the Steens and Picture Gorge basalt formations. Introduction During the middle to late Miocene epoch, the Columbia River flood basalts engulfed about of the Pacific Northwest, forming a large igneous province with an estimated volume of . Eruptions were most vigorous 17–14 million years ago, when over 99 percent of the basalt was released. Less extensive eruptions continued 14–6 million years ago. Erosion resulting from the Missoula Floods has extensively exposed these lava flows, laying bare many layers of the basalt flows at Wallula Gap, the lower Palouse River, the Columbia River Gorge and throughout the Channeled Scablands. The Columbia River Basalt Group is thought to be a potential link to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacial Lake Columbia
Glacial Lake Columbia was the lake formed on the ice-dammed Columbia River behind the Okanogan lobe of the Cordilleran Ice Sheet when the lobe covered of the Waterville Plateau west of Grand Coulee in central Washington state during the Wisconsin glaciation.The Wisconsin glaciation began about 80,000 years ago and ended around 10,000 years ago. Lake Columbia was a substantially larger version of the modern-day lake behind the Grand Coulee Dam. Lake Columbia's overflow – the diverted Columbia River – drained first through Foster Coulee, and as the ice dam grew, through first Moses Coulee, and finally, the Grand Coulee. Glacial Lake Missoula The Cordilleran ice sheet also blocked the Clark Fork River and created Glacial Lake Missoula, rising behind a high ice dam in flooded valleys of western Montana. Over 2000 years the ice dam periodically failed, releasing approximately 40 high-volume Missoula Floods of water down the Columbia River drainage, passing through gla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Jam
Ice jams occur when a topographic feature of the river causes floating river ice to accumulate and impede further progress downstream with the river current. Ice jams can significantly reduce the flow of a river and cause upstream flooding—sometimes called ice dams. Ice jam flooding can also occur downstream when the jam releases in an outburst flood. In either case, flooding can cause damage to structures on shore. Overview An ice blockage on a river is usually called an ''ice jam,'' but sometimes an ''ice dam''. An ice jam is an obstruction on a river formed by blocks of ice. Defined by the International Association of Hydraulic Research (IAHR) Working Group on River Ice Hydraulics an ice jam is a "stationary accumulation of fragmented ice or frazil that restricts flow" on a river or stream. The jam may effectively create a dam with an accumulation of anchor ice on the bottom of the river. On rivers the obstruction may be a change of width, structure, bend or decrease in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Banks Lake
Banks Lake is a long reservoir in central Washington in the United States. Part of the Columbia Basin Project, Banks Lake occupies the northern portion of the Grand Coulee, a formerly dry coulee near the Columbia River, formed by the Missoula Floods during the Pleistocene epoch. Grand Coulee Dam, built by the United States Bureau of Reclamation on the Columbia River created Franklin D. Roosevelt Lake, the reservoir on the river behind the dam. The surface of Lake Roosevelt is several hundred feet above the original Columbia River, making it easier to pump water up and out of the river's canyon into the adjacent Grand Coulee. Two low earth-fill dams, Dry Falls Dam and North Dam, keep the water in the Grand Coulee, thus creating the reservoir named Banks Lake. It is named after Frank A. Banks, the construction supervisor at Grand Coulee Dam. At the north end of Banks Lake the city of Grand Coulee and the town of Electric City are located. Steamboat Rock State Park is in the nor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Idaho Press
The University of Idaho Press is a university press that is part of the University of Idaho The University of Idaho (U of I, or UIdaho) is a public land-grant research university in Moscow, Idaho. It is the state's land-grant and primary research university,, and the lead university in the Idaho Space Grant Consortium. The Universit ...; their books are distributed by Caxton Press. External linksUniversity of Idaho Press books sold through Caxton Press Press Idaho, University of {{US-publish-company-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Channeled Scablands
The Channeled Scablands are a relatively barren and soil-free region of interconnected relict and dry flood channels, coulees and cataracts eroded into Palouse loess and the typically flat-lying basalt flows that remain after cataclysmic floods within the southeastern part of Washington.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. The Channeled Scablands were scoured by more than 40 cataclysmic floods during the Last Glacial Maximum and innumerable older cataclysmic floods over the last two million years. These floods were periodically unleashed whenever a large glacial lake broke through its ice dam and swept across eastern Washington and down the Columbia River Plateau during the Pleistocene epoch. The last of the cataclysmic floods occurred between 18,200 and 14,000 years ago.Balbas, A.M., Barth, A.M., Clark, P.U., Clark, J., Caffee, M., O'Connor, J., Baker, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Missoula Floods
The Missoula floods (also known as the Spokane floods or the Bretz floods or Bretz's floods) were cataclysmic glacial lake outburst floods that swept periodically across eastern Washington and down the Columbia River Gorge at the end of the last ice age. These floods were the result of periodic sudden ruptures of the ice dam on the Clark Fork River that created Glacial Lake Missoula. After each ice dam rupture, the waters of the lake would rush down the Clark Fork and the Columbia River, flooding much of eastern Washington and the Willamette Valley in western Oregon. After the lake drained, the ice would reform, creating Glacial Lake Missoula again. These floods have been researched since the 1920s. During the last deglaciation that followed the end of the Last Glacial Maximum, geologists estimate that a cycle of flooding and reformation of the lake lasted an average of 55 years and that the floods occurred several times over the 2,000-year period between 15,000 and 13,000 year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J Harlen Bretz
J Harlen Bretz (2 September 1882 – 3 February 1981) was an American geologist, best known for his research that led to the acceptance of the Missoula Floods and for his work on caves. Early life and education Bretz was born on 2 September 1882, in the small town of Saranac in Ionia County, Michigan. He was the first of Oliver Joseph Bretz and Rhoda Maria Howlett's five children. His father was a farmer, and proud descendant of early German settler in Ohio, John Bretz. The county's birth registry recorded his name as "Harlan J Bretz" at birth, but he was listed as "Harland J Bretz" on the 1900 United States Census. When he entered college in 1901, he applied as "J Harlen Bretz". At around the time he completed his graduate studies in 1913, he stopped using a point after the initial at "J". According to his two children, his given name was actually "Harley". Bretz's daughter Rhoda Bretz Riley went on to explain that "he invented the Harlen thing, just as he had invented the J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proglacial Lake
In geology, a proglacial lake is a lake formed either by the damming action of a moraine during the retreat of a melting glacier, a glacial ice dam, or by meltwater trapped against an ice sheet due to isostatic depression of the crust around the ice. At the end of the last ice age about 10,000 years ago, large proglacial lakes were a widespread feature in the northern hemisphere. Moraine-dammed The receding glaciers of the tropical Andes have formed a number of proglacial lakes, especially in the Cordillera Blanca of Peru, where 70% of all tropical glaciers are. Several such lakes have formed rapidly during the 20th century. These lakes may burst, creating a hazard for zones below. Many natural dams (usually moraines) containing the lake water have been reinforced with safety dams. Some 34 such dams have been built in the Cordillera Blanca to contain proglacial lakes. Several proglacial lakes have also formed in recent decades at the end of glaciers on the eastern side of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
