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Great Falls (Missouri River)
The Great Falls of the Missouri River are a series of waterfalls on the upper Missouri River in north-central Montana in the United States. From upstream to downstream, the five falls along a segment of the riverCutright, Paul Russell, and Johnsgard, Paul A. ''Lewis and Clark: Pioneering Naturalists.'' 2d ed. Lincoln, Neb.: University of Nebraska Press, 2003. are: *Black Eagle Falls () *Colter Falls () * Rainbow Falls () *Crooked Falls, also known as Horseshoe Falls () * Big Falls, also known as the Great Falls, () The Missouri River drops a total of from the first of the falls to the last, which includes a combined of vertical plunges and of riverbed descent. The Great Falls have been described as "spectacular", one of the "scenic wonders of America", and "a major geographic discovery". When the Lewis and Clark Expedition became the first white men to see the falls in 1805, Meriwether Lewis said they were the grandest sight he had beheld thus far in the journey.Pritchett, M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cascade County, Montana
Cascade County (''cascade'' means ''waterfall'' in French) is a county located in the U.S. state of Montana. As of the 2020 census, the population was 84,414, making it the fifth-most populous county in Montana. Its county seat is Great Falls. Cascade County comprises the Great Falls, MT Metropolitan Statistical Area. History At the time of the Lewis and Clark Expedition, Cascade County was the territory of the Blackfeet. The county was named for the falls on the Missouri River. The United States Army at one time had Fort Shaw as an outpost in the northwest part of the county. Only a small settlement is left by that name, a CDP. Geography According to the United States Census Bureau, the county has a total area of , of which is land and (0.5%) is water. The Missouri River and the Sun River flow through the county, and meet at the city of Great Falls. A portion of the Adel Mountains Volcanic Field is in the southwest corner of the county. The Rocky Mountains are in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Native Americans In The United States
Native Americans, also known as American Indians, First Americans, Indigenous Americans, and other terms, are the Indigenous peoples of the mainland United States ( Indigenous peoples of Hawaii, Alaska and territories of the United States are generally known by other terms). There are 574 federally recognized tribes living within the US, about half of which are associated with Indian reservations. As defined by the United States Census, "Native Americans" are Indigenous tribes that are originally from the contiguous United States, along with Alaska Natives. Indigenous peoples of the United States who are not listed as American Indian or Alaska Native include Native Hawaiians, Samoan Americans, and the Chamorro people. The US Census groups these peoples as " Native Hawaiian and other Pacific Islanders". European colonization of the Americas, which began in 1492, resulted in a precipitous decline in Native American population because of new diseases, wars, ethni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wyoming Craton
The Wyoming Craton is a craton in the west-central United States and western Canada – more specifically, in Montana, Wyoming, southern Alberta, southern Saskatchewan, and parts of northern Utah. Also called the Wyoming Province, it is the initial core of the continental crust of North America. The Wyoming Craton was sutured together with the Superior and Hearne- Rae cratons in the mountain-building episode that created the Trans-Hudson Suture Zone to form the core of North America (Laurentia). It was incorporated into southwest Laurentia approximately 1.86 billion years ago. Local preservation of 3.6–3.0 Ga gneisses and widespread isotopic evidence for crust of this age incorporated into younger plutons indicates that the Wyoming Craton originated as a 100,000 km2 middle Archean craton that was modified by late Archean volcanic magmatism and plate movements and Proterozoic extension and rifting. The Wyoming, Superior and Hearne-Ray cratons were once sections ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hearne Craton
The Hearne Craton is a craton in northern Canada which, together with the Rae Craton, forms the Western Churchill Province. Hearne is one of the six Archaean cratons of the Canadian Shield (the other being Slave, Rae, Wyoming, Superior, Nain) that are bound together by Palaeoproterozoic orogenic belts. Before being merged these six cratons formed independent microcontinents. Geological setting The Hearne Craton is separated from the Rae Craton by the -long Snowbird Tectonic Zone (STZ). During the Neoarchaean and Palaeoproterozoic the STZ played a major role when the Western Churchill Province was first assembled and then reworked. The STZ is a record of Neoarchaean plate tectonics similar in scale to modern orogenic belts. When Laurentia formed at 2.0–1.7 Ga Hearne and Rae formed a central strip to which the Slave, Superior, Sask, and Wyoming cratons were accreted. This strip is bounded by a series of orogens: the 1.92–1.69 Ga Trans-Hudson to the south ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continent
A continent is any of several large landmasses. Generally identified by convention rather than any strict criteria, up to seven geographical regions are commonly regarded as continents. Ordered from largest in area to smallest, these seven regions are: Asia, Africa, North America, South America, Antarctica, Europe, and Australia. "Most people recognize seven continents—Asia, Africa, North America, South America, Antarctica, Europe, and Australia, from largest to smallest—although sometimes Asia and Europe are considered a single continent, Eurasia." Variations with fewer continents may merge some of these, for example America, Eurasia, or Afro-Eurasia are sometimes treated as single continents, which can bring the total number as low as four. Zealandia, a largely submerged mass of continental crust, has also been described as a continent. Oceanic islands are frequently grouped with a nearby continent to divide all the world's land into geographical regions. Under t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archean
The Archean Eon ( , also spelled Archaean or Archæan) is the second of four geologic eons of Earth's history, representing the time from . The Archean was preceded by the Hadean Eon and followed by the Proterozoic. The Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ... during the Archean was mostly a water world: there was continental crust, but much of it was under an ocean deeper than today's ocean. Except for some trace minerals, today's oldest continental crust dates back to the Archean. Much of the geological detail of the Archean has been destroyed by subsequent activity. The Earliest known life forms, earliest known life started in the Archean. Life was simple throughout the Archean, mostly represented by shallow-water microbial mats called stromatolites, and the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basement (geology)
In geology, basement and crystalline basement are crystalline rocks lying above the mantle and beneath all other rocks and sediments. They are sometimes exposed at the surface, but often they are buried under miles of rock and sediment. The basement rocks lie below a sedimentation, sedimentary platform (geology), platform or cover, or more generally any rock below sedimentary rocks or sedimentary basins that are metamorphic rock, metamorphic or Igneous rock, igneous in origin. In the same way, the sediments or sedimentary rocks on top of the basement can be called a "cover" or "sedimentary cover". Crustal rocks are modified several times before they become basement, and these transitions alter their composition. Continental crust Basement rock is the thick foundation of ancient, and oldest, metamorphic and igneous rock that forms the Crust (geology), crust of continents, often in the form of granite. Basement rock is contrasted to overlying sedimentary rocks which are laid down ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Province
A geologic province is a spatial entity with common geologic attributes. A province may include a single dominant structural element such as a basin or a fold belt, or a number of contiguous related elements. Adjoining provinces may be similar in structure but be considered separate due to differing histories. Geologic provinces by origin Geologic provinces by resources Some studies classify provinces based upon mineral resources, such as mineral deposits. There are a particularly large number of provinces identified worldwide for petroleum and other mineral fuels, such as the Niger Delta petroleum province. See also * Physiographic province * Geomorphology * United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ... References * External lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shear (geology)
Boudinaged quartz vein (with strain fringe) showing ''Fault (geology)">sinistral shear sense'', Starlight Pit, Fortnum Gold Mine, Western Australia In geology, shear is the response of a rock to deformation usually by compressive stress and forms particular textures. Shear can be homogeneous or non-homogeneous, and may be pure shear or simple shear. Study of geological shear is related to the study of structural geology, rock microstructure or rock texture and fault mechanics. The process of shearing occurs within brittle, brittle-ductile, and ductile rocks. Within purely brittle rocks, compressive stress results in fracturing and simple faulting. Rocks Rocks typical of shear zones include mylonite, cataclasite, S-tectonite and L-tectonite, pseudotachylite, certain breccias and highly foliated versions of the wall rocks. Shear zone A shear zone is a tabular to sheetlike, planar or curviplanar zone composed of rocks that are more highly strained than rocks adjacent to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Falls Tectonic Zone
The Great Falls Tectonic Zone is a major intracontinental shear zone between the Hearne craton and Wyoming craton basement rock of the Archean Eon which form part of the North American continent.Boerner, D.E.; Craven, J.A.; Kurtz, R.D.; Ross, G.M.; and Jones, F.W. "The Great Falls Tectonic Zone: Suture or Intracontinental Shear Zone?" ''Canadian Journal of Earth Sciences.'' 35:2 (1998).Mueller, Paul A.; Heatherington, Ann L.; Kelly, Dawn M.; Wooden, Joseph L.; and Mogk, David W. "Paleoproterozoic Crust Within the Great Falls Tectonic Zone: Implications for the Assembly of Southern Laurentia." ''Geology.'' 30:2 (February 2002).Harms, Tekla A.; Brady, John B.; Burger, H. Robert; and Cheney, John T. "Advances in the Geology of the Tobacco Root Mountains, Montana, and Their Implications for the History of the Northern Wyoming Province." ''Precambrian Geology of the Tobacco Root Mountains, Montana.'' Special Papers, Volume 377. John B. Brady, H. Robert Burger, John T. Cheney, and Tekla A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacial Lakes In Montana
A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate between glacial periods. The Last Glacial Period ended about 15,000 years ago. The Holocene is the current interglacial. A time with no glaciers on Earth is considered a greenhouse climate state. Quaternary Period Within the Quaternary, which started about 2.6 million years before present, there have been a number of glacials and interglacials. At least eight glacial cycles have occurred in the last 740,000 years alone. Penultimate Glacial Period The Penultimate Glacial Period (PGP) is the glacial period that occurred before the Last Glacial Period. It began about 194,000 years ago and ended 135,000 years ago, with the beginning of the Eemian interglacial. Last Glacial Period The last glacial period was the most recent glacial period wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Colter
John Colter (c.1770–1775 – May 7, 1812 or November 22, 1813) was a member of the Lewis and Clark Expedition (1804–1806). Though party to one of the more famous expeditions in history, Colter is best remembered for explorations he made during the winter of 1807–1808, when he became the first known person of European descent to enter the region which later became Yellowstone National Park and to see the Teton Mountain Range. Colter spent months alone in the wilderness and is widely considered to be the first known mountain man. Early life John Colter was born in Stuarts Draft, Colony of Virginia in 1774, based on assumptions by his family. There is some debate as to which variation of the family name, Coalter, Coulter, or Colter, is correct, and the issue was further convoluted by William Clark utilizing all three spelling variations during his daily journals. It is unknown whether Colter was literate or knew how to write. Two signatures possessed by the Missouri St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
