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Amphitheater Mountain (Washington)
Amphitheater Mountain is an multi-peak mountain located in Okanogan County in Washington state. It is part of the Okanogan Range which is a sub-range of the North Cascades and Cascade Range. The mountain is situated on the east side of the Cascade crest, in the Pasayten Wilderness, on land administered by the Okanogan–Wenatchee National Forest. The sprawling Amphitheater Mountain has several sub-peaks including the South Peak (), West Peak (), and North Peak (). The nearest higher peak is Cathedral Peak, to the north. The Pacific Northwest Trail traverses below the north slope of Amphitheater Mountain as it crosses Cathedral Pass. Precipitation runoff from Amphitheater Mountain drains west into Cathedral Fork, or east into Cathedral Creek. Climate Weather fronts originating in the Pacific Ocean travel northeast toward the Cascade Mountains. As fronts approach the North Cascades, they are forced upward by the peaks of the Cascade Range (orographic lift), causing them to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cathedral Peak (Washington)
Cathedral Peak is an mountain summit located in Okanogan County in Washington state. It is part of the Okanogan Range which is a sub-range of the North Cascades. The mountain is situated in the Pasayten Wilderness, on land administered by the Okanogan–Wenatchee National Forest. The nearest higher peak is Grimface Mountain, to the north in Cathedral Provincial Park in Canada. The Pacific Northwest Trail traverses below the south slope of Cathedral Peak as it crosses Cathedral Pass. Less than a mile to the opposite side of the pass stands Amphitheater Mountain. Precipitation runoff from Cathedral Peak drains west into Cathedral Fork, or east into Cathedral Creek. Climate Most weather fronts originate in the Pacific Ocean, and travel northeast toward the Cascade Mountains. As fronts approach the North Cascades, they are forced upward by the peaks of the Cascade Range, causing them to drop their moisture in the form of rain or snowfall onto the Cascades ( Orographic li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''Ēṓs'', 'Eos, Dawn') and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.See: *Letter from William Whewell to Charles Lyell dated 31 January 1831 in: * From p. 55: "The period next antecedent we shall call Eocene, from ήως, aurora, and χαινος, recens, because the extremely small proportion of living species contained in these strata, indicates what may be considered the first commencement, or ''dawn'', of the existing state of the animate creation." The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isoto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Okanagan Range
The Okanagan Range or Okanogan Range is a small subrange of the Cascade Range straddling the border between British Columbia and Washington (U.S. state), Washington south of the Similkameen River on the inland side of the range. The range is the northeasternmost extremity of the Cascade Range. According to Fred Beckey there are differences of opinion about the names and locations of the subranges of the northern Cascades, especially between Canadian and American geographers. Nevertheless early geologists and topographers had a fundamental agreement about the location and names of the subranges. The Okanagan Range was seen as bounded by the Pasayten River on the west and continuing east to Chopaka Mountain. The Hozameen Range was seen as separated from the Okanagan Range by the Pasayten River. This definition of the Okanagan Range included most of today's Pasayten Wilderness and extending south to joins the main Cascade Range at Harts Pass, near the headwaters of the Methow River. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of The Pacific Northwest
The geology of the Pacific Northwest includes the composition (including rock, minerals, and soils), structure, physical properties and the processes that shape the Pacific Northwest region of North America. The region is part of the Ring of Fire: the subduction of the Pacific and Farallon Plates under the North American Plate is responsible for many of the area's scenic features as well as some of its hazards, such as volcanoes, earthquakes, and landslides. The geology of the Pacific Northwest is vast and complex. Most of the region began forming about 200 million years ago as the North American Plate started to drift westward during the rifting of Pangaea. Since that date, the western edge of North America has grown westward as a succession of island arcs and assorted ocean-floor rocks have been added along the continental margin. There are at least five geologic provinces in the area: the Cascade Volcanoes, the Columbia Plateau, the North Cascades, the Coast Mountains, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geography Of The North Cascades
The geography of the North Cascades describes a range of rugged mountains in British Columbia, Canada and Washington, United States. In Canada, the range is officially named the Cascade Mountains but is commonly referred to as the Canadian Cascades. Extent The Fraser River and Similkameen River in British Columbia form the northern boundary of the North Cascades. On the east, the Okanogan River and the Columbia River bound the range. On the west within the United States, the foothills of the range are separated by a narrow coastal plain from Puget Sound, whereas in Canada there are few if any foothills and the range drops steeply to the floodplain of the Fraser Lowland. The southern boundary of the North Cascades is less definite. For the purposes of this article, it will be taken as US Highway 2, running over Stevens Pass, or equivalently, the Skykomish River, Nason Creek, and the lower Wenatchee River. This roughly follows Beckey's division. Sometimes the southern boundary i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
In geology, a fault is a Fracture (geology), planar fracture or discontinuity in a volume of Rock (geology), rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust (geology), crust result from the action of Plate tectonics, plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction, subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the Plane (geometry), plane that represents the fracture surface of a fault. A ''fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geological maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orogeny
Orogeny () is a mountain-mountain formation, building process that takes place at a convergent boundary, convergent plate margin when plate motion compresses the margin. An or develops as the compressed plate crumples and is tectonic uplift, uplifted to form one or more mountain ranges. This involves a series of geological processes collectively called orogenesis. These include both structural deformation (physics), deformation of existing continental crust and the creation of new continental crust through volcanism. Magma rising in the orogen carries less dense material upwards while leaving more dense material behind, resulting in compositional differentiation of Earth's lithosphere (crust (geology), crust and uppermost mantle (geology), mantle). A synorogenic (or synkinematic) process or event is one that occurs during an orogeny. The word ''orogeny'' comes . Although it was used before him, the American geologist Grove Karl Gilbert, G. K. Gilbert used the term in 1890 to me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek () 'most' and (; Latinized as ) 'new'. The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, oscillating between cold Glacial period, glacial periods and warmer Interglacial, int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terrane
In geology, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its distinctive geologic history, which is different from the surrounding areas—hence the term "exotic" terrane. The suture zone between a terrane and the crust it attaches to is usually identifiable as a fault. A sedimentary deposit that buries the contact of the terrane with adjacent rock is called an overlap formation. An igneous intrusion that has intruded and obscured the contact of a terrane with adjacent rock is called a stitching pluton. There is also an older usage of the term ''terrane'', which described a series of related rock formations or an area with a preponderance of a particular rock or rock group. Overview A tectonostratigraphic terrane did not necessarily originate as an independent microplate, since it may not contain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continental Lithosphere
A lithosphere () is the rigid, outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust and the lithospheric mantle, the topmost portion of the upper mantle that behaves elastically on time scales of up to thousands of years or more. The crust and upper mantle are distinguished on the basis of chemistry and mineralogy. Earth's lithosphere Earth's lithosphere, which constitutes the hard and rigid outer vertical layer of the Earth, includes the crust and the lithospheric mantle (or mantle lithosphere), the uppermost part of the mantle that is not convecting. The layer below the lithosphere is called the asthenosphere, which is the weaker, hotter, and deeper part of the upper mantle that is able to convect. The lithosphere–asthenosphere boundary is defined by a difference in response to stress. The lithosphere remains rigid for very long periods of geologic time in which it deforms elastically and through brittle failure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcano
A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and because most of Earth's plate boundaries are underwater, most volcanoes are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes resulting from divergent tectonic activity are usually non-explosive whereas those resulting from convergent tectonic activity cause violent eruptions."Mid-ocean ridge tectonics, volcanism and geomorphology." Geology 26, no. 455 (2001): 458. https://macdonald.faculty.geol.ucsb.edu/papers/Macdonald%20Mid-Ocean%20Ridge%20Tectonics.pdf Volcanoes can also form where there is str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
