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Intermontane Belt
The Intermontane Belt is a physiogeological region in the Pacific Northwest of North America, stretching from northern Washington into British Columbia, Yukon, and Alaska. It comprises rolling hills, high plateaus and deeply cut valleys. The rocks in the belt have very little similarities with the North American continent. Geology The formation of the Intermontane Belt is complex. It began forming during the early Jurassic period when an island arc called the Intermontane Islands collided against a pre-existing continental margin. This island arc is believed to have formed on a pre-existing tectonic plate called the Intermontane Plate about 245 million years ago by subduction of the former Insular Plate during the Triassic period. This subduction zone records another subduction zone called the Intermontane Trench under an ancient ocean between the Intermontane Islands and the former continental margin of North America called the Slide Mountain Ocean. This arrangement of two par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Belts Of Western Canada
Geology () is a branch of natural science concerned with Earth and other Astronomical object, astronomical objects, the features or rock (geology), rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth science, Earth sciences, including hydrology, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the Relative dating, relative and Geochronology, absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Eart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subduction
Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the heavier plate dives beneath the second plate and sinks into the mantle. A region where this process occurs is known as a subduction zone, and its surface expression is known as an arc-trench complex. The process of subduction has created most of the Earth's continental crust. Rates of subduction are typically measured in centimeters per year, with the average rate of convergence being approximately two to eight centimeters per year along most plate boundaries. Subduction is possible because the cold oceanic lithosphere is slightly denser than the underlying asthenosphere, the hot, ductile layer in the upper mantle underlying the cold, rigid lithosphere. Once initiated, stable subduction is driven mostly by the negative buoyancy of the de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methow Valley
The Methow River ( ) is a tributary of the Columbia River in northern Washington in the United States. The river's watershed drains the eastern North Cascades, with a population of about 5,000 people. The Methow's watershed is characterized by relatively pristine habitats, as much of the river basin is located in national forests and wildernesses. Many tributaries drain the large Pasayten Wilderness. An earlier economy based on agriculture is giving way to one based on recreation and tourism. History The river was named after the Methow Native Americans (today part of the Confederated Tribes of the Colville Indian Reservation). The name "Methow" comes from the Okanagan placename ''/mətxʷú/'', meaning "sunflower (seeds)". The Native American name for the river was ''Buttlemuleemauch'', meaning "salmon falls river". In 1841 the Wilkes Expedition named the river "Barrier River". Alexander Ross said the native name was Buttle-mule-emauch. In 1811 David Thompson met the tribe li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kootenay Fold Belt
Kootenay, Kootenai, and Kutenai may refer to: Ethnic groups *The Kutenai, also known as the Ktunaxa, Kootenai, or Kootenay, an indigenous people of the United States and Canada **Kutenai language, the traditional language of the Kutenai **Ktunaxa Nation, a First Nations government in British Columbia, Canada **Kootenai Tribe of Idaho, a federally recognized tribe in Idaho, United States, ** Confederated Salish and Kootenai Tribes, a federally recognized tribe in Montana, United States Places Communities *Kootenai, Idaho, United States *Kootenay, British Columbia, Canada *Kootenay Bay, an unincorporated community in British Columbia, Canada *Kootenai County, Idaho, United States *Diocese of Kootenay, a diocese of the Ecclesiastical Province of British Columbia and the Yukon of the Anglican Church of Canada *List of electoral districts in the Kootenays, electoral districts in the Kootenays region of British Columbia **Kootenay (electoral district), a former electoral district in Br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountain Range
A mountain range or hill range is a series of mountains or hills arranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have arisen from the same cause, usually an orogeny. Mountain ranges are formed by a variety of geological processes, but most of the significant ones on Earth are the result of plate tectonics. Mountain ranges are also found on many planetary mass objects in the Solar System and are likely a feature of most terrestrial planets. Mountain ranges are usually segmented by highlands or mountain passes and valleys. Individual mountains within the same mountain range do not necessarily have the same geologic structure or petrology. They may be a mix of different orogenic expressions and terranes, for example thrust sheets, uplifted blocks, fold mountains, and volcanic landforms resulting in a variety of rock types. Major ranges Most geolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Igneous Rock
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main The three types of rocks, rock types, the others being Sedimentary rock, sedimentary and metamorphic rock, metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava. The magma can be derived from Partial melting, partial melts of existing rocks in either a Terrestrial planet, planet's mantle (geology), mantle or crust (geology), crust. Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive (geology), extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, or without crystallization to form Volcanic glass, natural glasses. Igneous rocks occur in a wide range of geological settings: shields, platforms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Rock
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment, and may be composed of geological detritus (minerals) or biological detritus (organic matter). The geological detritus originated from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement, which are called agents of denudation. Biological detritus was formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies (marine snow). Sedimentation may also occur as dissolved minerals precipitate from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fold (geology)
In structural geology, a fold is a stack of originally planar surfaces, such as sedimentary strata, that are bent or curved during permanent deformation. Folds in rocks vary in size from microscopic crinkles to mountain-sized folds. They occur as single isolated folds or in periodic sets (known as ''fold trains''). Synsedimentary folds are those formed during sedimentary deposition. Folds form under varied conditions of stress, pore pressure, and temperature gradient, as evidenced by their presence in soft sediments, the full spectrum of metamorphic rocks, and even as primary flow structures in some igneous rocks. A set of folds distributed on a regional scale constitutes a fold belt, a common feature of orogenic zones. Folds are commonly formed by shortening of existing layers, but may also be formed as a result of displacement on a non-planar fault (''fault bend fold''), at the tip of a propagating fault (''fault propagation fold''), by differential compaction or due to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North American Plate
The North American Plate is a tectonic plate covering most of North America, Cuba, the Bahamas, extreme northeastern Asia, and parts of Iceland and the Azores. With an area of , it is the Earth's second largest tectonic plate, behind the Pacific Plate (which borders the plate to the west). It extends eastward to the Mid-Atlantic Ridge and westward to the Chersky Range in eastern Siberia. The plate includes both continental and oceanic crust. The interior of the main continental landmass includes an extensive granitic core called a craton. Along most of the edges of this craton are fragments of crustal material called terranes, which are accreted to the craton by tectonic actions over a long span of time. It is thought that much of North America west of the Rocky Mountains is composed of such terranes. Boundaries The southern boundary with the Cocos Plate to the west and the Caribbean Plate to the east is a transform fault, represented by the Swan Islands Transform Fault unde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asia
Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area of , about 30% of Earth's total land area and 8.7% of Earth's total surface area. The continent, which has long been home to the majority of the human population, was the site of many of the first civilizations. Its 4.7 billion people constitute roughly 60% of the world's population. In general terms, Asia is bounded on the east by the Pacific Ocean, on the south by the Indian Ocean, and on the north by the Arctic Ocean. The border of Asia with Europe is a historical and cultural construct, as there is no clear physical and geographical separation between them. It is somewhat arbitrary and has moved since its first conception in classical antiquity. The division of Eurasia into two continents reflects East–West cultural, linguistic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philippine Mobile Belt
In the geology of the Philippines, the Philippine Mobile Belt is a complex portion of the tectonic boundary between the Eurasian Plate and the Philippine Sea Plate, comprising most of the country of the Philippines. It includes two subduction zones, the Manila Trench to the west and the Philippine Trench to the east, as well as the Philippine Fault System. Within the Belt, a number of crustal blocks or microplates which have been shorn off the adjoining major plates are undergoing massive deformation. Most segments of the Philippines, including northern Luzon, are part of the Philippine Mobile Belt, which is bounded by the Philippine Sea Plate to the east, the Molucca Sea Collision Zone to the south, Sunda Plate to the southwest, and the South China Sea Basin to the west and north-west. To the north it ends in eastern Taiwan, the zone of active collision between the North Luzon Trough portion of the Luzon Volcanic Arc and South China. The Philippine Mobile Belt has also been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slide Mountain Ocean
The Slide Mountain Ocean was an ancient ocean that existed between the Intermontane Islands and North America beginning around 245 million years ago in the Triassic period. It is named after the Slide Mountain Terrane, which is composed of rocks from the ancient oceanic floor. There was a subduction zone on the Slide Mountain Ocean's floor called the Intermontane Trench where the Intermontane Plate The Intermontane Plate was an ancient oceanic tectonic plate that lay on the west coast of North America about 195 million years ago. The Intermontane Plate was surrounded by a chain of volcanic islands called the Intermontane Islands, which had b ... was being subducted under North America. The floor of the Slide Mountain Ocean was pushed up onto the ancient margin of North America. References Historical oceans Triassic paleogeography {{triassic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
