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Intermontane
Intermontane is a physiographic adjective formed from the prefix " inter-" (''signifying among, between, amid, during, within, mutual, reciprocal'') and the adjective "montane" (inhabiting, or growing in mountainous regions, especially cool, moist upland slopes below the timberline). The corresponding ''physiographic'' noun is intermountain, while the noun ''intermontane'' is an ''ecologic'' noun meaning ''among, between, amid, or within " flora and fauna of a montane habitat.''" As an example, an alpine region would be an intermontane for a species that migrates between a glacial region and a subalpine region. Use of the term *Intermontane Basin, a wide valley between mountain ranges that is partly filled with alluvium such as New Zealand's Mackenzie Basin. *Intermontane Belt, a physiogeological region in the North American Pacific Northwest. *Intermontane Plateaus, the United States physiographic region of the Intermountain West. *Intermontane Steppe, a term used mainly i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
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 been accumulating as a volcanic chain in the Pacific Ocean since the Triassic period, beginning around 245 million years ago. The volcanism records yet another subduction zone. Beneath the far edge of the Intermontane microplate, another plate called the Insular Plate was sinking. This arrangement with two parallel subduction zones is unusual. The modern Philippine Islands are located on the Philippine Mobile Belt, one of the few places on Earth where twin subduction zones exist today. Geologists call the ocean between the Intermontane islands and North America the Slide Mountain Ocean. The name comes from the Slide Mountain Terrane, a region made of rocks from the floor of the ancient ocean. Collision of the Intermontane Islands During ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intermontane Islands
The Intermontane Islands were a giant chain of active volcanic islands somewhere in the Pacific Ocean during the Triassic time beginning around 245 million years ago. They were 600 to long and rode atop a microplate known as the Intermontane Plate. Over early Jurassic time the Intermontane Islands and the Pacific Northwest drew closer together as the continent moved west and the Intermontane Plate subducted. About 180 million years ago in the Mid-Jurassic time the last of the Intermontane Plate subducted and the Intermontane Islands collided with the Pacific Northwest, forming parts of British Columbia, Canada. The Intermontane Islands were too big to sink beneath the continent, and welded onto the continent, forming the Intermontane Belt. Geologists call the ocean that existed between the Intermontane Islands and North America the Slide Mountain Ocean. See also *Island arc * Insular Islands *Intermontane Plate *Intermontane Belt The Intermontane Belt is a physiogeological regi ... [...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] |
Oceanic Trench
Oceanic trenches are prominent long, narrow topographic depressions of the ocean floor. They are typically wide and below the level of the surrounding oceanic floor, but can be thousands of kilometers in length. There are about of oceanic trenches worldwide, mostly around the Pacific Ocean, but also in the eastern Indian Ocean and a few other locations. The greatest ocean depth measured is in the Challenger Deep of the Mariana Trench, at a depth of below sea level. Oceanic trenches are a feature of the Earth's distinctive plate tectonics. They mark the locations of convergent plate boundaries, along which lithospheric plates move towards each other at rates that vary from a few millimeters to over ten centimeters per year. Oceanic lithosphere moves into trenches at a global rate of about 3 km2/yr. A trench marks the position at which the flexed, subducting slab begins to descend beneath another lithospheric slab. Trenches are generally parallel to and about from a vol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intermontane Trench
The Intermontane Trench was an ancient oceanic trench during the Triassic. The trench was probably long, parallel to the west coast of North America. The ocean that the trench was located in was called the Slide Mountain Ocean. See also *Intermontane Islands *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 ... External linksBurke Museum - University of Washington Historical geology Oceanic trenches of the Pacific Ocean Triassic paleogeography Landforms of North America Subduction zones {{palaeo-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Physiographic Region
The physiographic regions of the contiguous United States The contiguous United States (officially the conterminous United States) consists of the 48 adjoining U.S. states and the Federal District of the United States of America. The term excludes the only two non-contiguous states, Alaska and Hawaii ... comprise 8 regions, 25 provinces, and 85 sections. The system dates to Nevin Fenneman's paper ''Physiographic Subdivision of the United States'', published in 1917. Fenneman expanded and presented his system more fully in two books, ''Physiography of western United States'' (1931), and ''Physiography of eastern United States'' (1938). In these works Fenneman described 25 provinces and 85 sections of the United States physiography. Physiographic divisions References {{DEFAULTSORT:United States Physiographic Region ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intermontane Plateaus
In the context of physical geography, the Intermontane Intermontane is a physiographic adjective formed from the prefix " inter-" (''signifying among, between, amid, during, within, mutual, reciprocal'') and the adjective "montane" (inhabiting, or growing in mountainous regions, especially cool, moi ... Plateaus is one of eight Physiographic Regions of the United States, physiographic regions of the contiguous United States. The region consists mostly of plateaus and mountain ranges lying between the Rocky Mountains on the east and the Cascade Range, Cascade and Sierra Nevada Mountains on the west. It is subdivided into three physiographic provinces: the Columbia Plateau in the north, the Basin and Range Province in the central and southwestern portions, and the Colorado Plateau in the southeast. In turn, each of these provinces are each subdivided into a number of physiographic sections. Physiographic provinces Columbia Plateau Province The Columbia Plateau Province is a l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intermountain West
The Intermountain West, or Intermountain Region, is a geographic and geological region of the Western United States. It is located between the front ranges of the Rocky Mountains on the east and the Cascade Range and Sierra Nevada on the west. Topography The Intermountain West has a basin and range and plateau topography. Some of the region's rivers reach the Pacific Ocean, such as the Columbia River and Colorado River. Other regional rivers and streams are in endorheic basins and cannot reach the sea, such as the Walker River and Owens River. These flow into brackish or seasonally dry lakes or desert sinks. Portions of this region include: * Basin and Range Province * Colorado Plateau * Great Basin * Intermontane Plateaus Climate The climate of the Intermountain Region is affected by location and elevation. The sub-regions are in rain shadows from the Cascade or Sierra Nevada ranges that block precipitation from Pacific storms. The winter weather depends on latitude. In t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pacific Northwest
The Pacific Northwest (sometimes Cascadia, or simply abbreviated as PNW) is a geographic region in western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though no official boundary exists, the most common conception includes the U.S. states of Oregon, Washington (state), Washington, and Idaho, and the Canadian province of British Columbia. Some broader conceptions reach north into Alaska and Yukon, south into northern California, and east into western Montana. Other conceptions may be limited to the coastal areas west of the Cascade Mountains, Cascade and Coast Mountains, Coast mountains. The variety of definitions can be attributed to partially overlapping commonalities of the region's history, culture, geography, society, ecosystems, and other factors. The Northwest Coast is the coastal region of the Pacific Northwest, and the Northwest Plateau (also commonly known as "British Columbia Interi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tectonic Plate
Plate tectonics (from the la, label=Late Latin, tectonicus, from the grc, τεκτονικός, lit=pertaining to building) is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large tectonic plates which have been slowly moving since about 3.4 billion years ago. The model builds on the concept of ''continental drift'', an idea developed during the first decades of the 20th century. Plate tectonics came to be generally accepted by geoscientists after seafloor spreading was validated in the mid to late 1960s. Earth's lithosphere, which is the rigid outermost shell of the planet (the crust and upper mantle), is broken into seven or eight major plates (depending on how they are defined) and many minor plates or "platelets". Where the plates meet, their relative motion determines the type of plate boundary: '' convergent'', '' divergent'', or ''transform''. Earthquakes, volcanic activity, mountain-building, and oceanic tren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triassic
The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the chief terrestrial vertebrates during this time. A specialized subgroup of archo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
