|
Bonneville Flood
The Bonneville flood was a catastrophic flooding event in the last ice age, which involved massive amounts of water inundating parts of southern Idaho and eastern Washington along the course of the Snake River. Unlike the Missoula Floods, which also occurred during the same period in the Pacific Northwest, the Bonneville flood only happened once. The flood is believed to be the second largest in known geologic history. Cause and events About 14,500 years ago (radiocarbon dating, 17,400 years ago calendar, "calibrated" dating), pluvial Lake Bonneville in northern Utah reached its highest water level since its formation. The lake occupied the present-day basin of the Great Salt Lake, and was far larger, covering about . As it rose the lake level caused seepage at, then breached, the ancient level of Red Rock Pass, a mountain pass at the headwaters of the Portneuf River, a tributary of the Snake River above present-day American Falls Reservoir. Ancient Red Rock Pass was the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Bonneville Map
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger oceans, they do form part of the Earth's water cycle. Lakes are distinct from lagoons, which are generally coastal parts of the ocean. Lakes are typically larger and deeper than ponds, which also lie on land, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which usually flow in a channel on land. Most lakes are fed and drained by rivers and streams. Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers, where a river channel has widened into a basin. Some parts of the world have many lakes formed by the chaotic drainage patterns left over from the last ic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alluvial Fan
An alluvial fan is an accumulation of sediments that fans outwards from a concentrated source of sediments, such as a narrow canyon emerging from an escarpment. They are characteristic of mountainous terrain in arid to semiarid climates, but are also found in more humid environments subject to intense rainfall and in areas of modern glaciation. They range in area from less than to almost . Alluvial fans typically form where flow emerges from a confined channel and is free to spread out and infiltrate the surface. This reduces the carrying capacity of the flow and results in deposition of sediments. The flow can take the form of infrequent debris flows or one or more ephemeral or perennial streams. Alluvial fans are common in the geologic record, such as in the Triassic basins of eastern North America and the New Red Sandstone of south Devon. Such fan deposits likely contain the largest accumulations of gravel in the geologic record. Alluvial fans have also been found on Mar ... [...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] |
Columbia River
The Columbia River ( Upper Chinook: ' or '; Sahaptin: ''Nch’i-Wàna'' or ''Nchi wana''; Sinixt dialect'' '') is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada. It flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state of Oregon before emptying into the Pacific Ocean. The river is long, and its largest tributary is the Snake River. Its drainage basin is roughly the size of France and extends into seven US states and a Canadian province. The fourth-largest river in the United States by volume, the Columbia has the greatest flow of any North American river entering the Pacific. The Columbia has the 36th greatest discharge of any river in the world. The Columbia and its tributaries have been central to the region's culture and economy for thousands of years. They have been used for transportation sinc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continents of Asia and Oceania in the west and the Americas in the east. At in area (as defined with a southern Antarctic border), this largest division of the World Ocean—and, in turn, the hydrosphere—covers about 46% of Earth's water surface and about 32% of its total surface area, larger than Earth's entire land area combined .Pacific Ocean . '' Britannica Concise.'' 2008: Encyclopædia Britannica, Inc. The centers of both the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hells Canyon
Hells Canyon is a canyon in the Western United States, located along the border of eastern Oregon, a small section of eastern Washington and western Idaho. It is part of the Hells Canyon National Recreation Area which is also located in part of the Wallowa-Whitman National Forest. It is North America's deepest river gorge at . Notably, Hells Canyon runs deeper than the better-known Grand Canyon in Arizona. The canyon was carved by the waters of the Snake River, which flows more than below the canyon's west rim on the Oregon side and below the peaks of Idaho's Seven Devils Mountains to the east. This area includes of wilderness. Most of the area is inaccessible by road. Geology The geologic history of the rocks of Hells Canyon began 300 million years ago with an arc of volcanoes that emerged from the waters of the Pacific Ocean. Over millions of years, the volcanoes subsided and limestone built up on the underwater platforms. The basins between them were filled wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salmon Falls Creek
Salmon Falls Creek is a tributary of the Snake River, flowing from northern Nevada into Idaho in the United States. Formed in high mountains at the northern edge of the Great Basin, Salmon Falls Creek flows northwards ,U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed May 3, 2011 draining an arid and mountainous basin of . The Salmon Falls Creek valley served as a trade route between the Native American groups of the Snake River Plain and Great Basin. Today, most of its water is used for irrigation. Course Salmon Falls Creek rises in the arid Jarbidge Mountains of northern Nevada at the confluence of its North and South Forks. The North Fork, sometimes considered the main stem of Salmon Falls Creek, is long, and the South Fork long. Many of the creek's headwater streams originate in the Humboldt National Forest and converge to form a short canyon. At the confluence with Jakes Creek the creek swings northeast in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bruneau River
The Bruneau River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. tributary of the Snake River, in the U.S. states of Idaho and Nevada. It runs through a narrow canyon cut into ancient lava flows in southwestern Idaho. The Bruneau Canyon, which is up to deep and long, features rapids and hot springs, making it a popular whitewater trip. The Bruneau River's drainage basin is bounded by the Jarbidge Mountains to the southeast, the Owyhee Mountains and Chalk Hills to the west, and the Bruneau Plateau to the east. Course The Bruneau River system originates within and near the Jarbidge and Mountain City Ranger Districts of the Humboldt-Toiyabe National Forest in northern Elko County. The three main streams are the East Fork Bruneau River, the West Fork Bruneau River, and the Jarbidge River, all of which flow generally north. The Jarbidge River joins the West Fork, then the East and West Forks join to form the mainstem Bruneau River. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shoshone Falls
Shoshone Falls () is a waterfall in the western United States, on the Snake River in south-central Idaho, approximately northeast of the city of Twin Falls. Sometimes called the "Niagara of the West," Shoshone Falls is in height, higher than Niagara Falls, and flows over a rim nearly in width. Formed by the cataclysmic outburst flooding of Lake Bonneville during the Pleistocene ice age about 14,000 years ago, Shoshone Falls marks the historical upper limit of fish migration (including salmon) in the Snake River, and was an important fishing and trading place for Native Americans. The falls were documented by Europeans as early as the 1840s; despite the isolated location, it became a tourist attraction starting in the 1860s. At the beginning of the 20th century, part of the Snake River was diverted for irrigation of the Magic Valley. Now, the flows over the falls can be viewed seasonally based on snowfall, irrigation needs and hydroelectric demands. Irrigation and hydroele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loess
Loess (, ; from german: Löss ) is a clastic, predominantly silt-sized sediment that is formed by the accumulation of wind-blown dust. Ten percent of Earth's land area is covered by loess or similar deposits. Loess is a periglacial or aeolian (windborne) sediment, defined as an accumulation of 20% or less of clay and a balance of roughly equal parts sand and silt (with a typical grain size from 20 to 50 micrometers), often loosely cemented by calcium carbonate. It is usually homogeneous and highly porous and is traversed by vertical capillaries that permit the sediment to fracture and form vertical bluffs. Properties Loess is homogeneous, porous, friable, pale yellow or buff, slightly coherent, typically non-stratified and often calcareous. Loess grains are angular, with little polishing or rounding, and composed of crystals of quartz, feldspar, mica and other minerals. Loess can be described as a rich, dust-like soil. Loess deposits may become very thick, more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of Venus, which cover ~80% of the surface, are basaltic; the lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flows that can spread over great areas before cooling and solidifying. Flood basalts are t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snake River Canyon (Idaho)
Snake River Canyon is a canyon formed by the Snake River in the Magic Valley region of southern Idaho, forming part of the boundary between Twin Falls County to the south and Jerome County to the north. The canyon ranges up to 500 feet (150 meters) deep and 0.25 miles (0.4 kilometers) wide, and runs for just over 50 miles. Perrine Bridge crosses the canyon immediately north of the city of Twin Falls. Shoshone Falls is located approximately 5 miles (8 kilometers) east of Perrine Bridge along the canyon. The canyon continues through Glenns Ferry and south of Boise, making it longer than 50 miles. History In the late 19th century I. B. Perrine and others founded the Magic Valley's first successful agricultural operations on the Snake River Canyon floor. The canyon's value as a farming area diminished after irrigation projects made agriculture practical in the surrounding areas in the early 20th century. Today the canyon floor is a tourist attraction and features several parks ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Pacific Ocean")
