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Sawtooth Mountain (Montana)
Sawtooth Mountain is a shield volcano, and part of the polygenetic Indian Heaven Volcanic Field in Washington, United States. It is located midway between Mount St. Helens and Mount Adams, and dates from the Pleistocene and Holocene. Sawtooth Mountain is the third highest point at in this region. The mountain forms a series of welded volcanic rock spires, an eroded remnant of an ancient shield volcano. Sawtooth Mountain is the third highest point in the Indian Heaven Wilderness Area. While Sawtooth Mountain is not the highest, its craggy appearance makes it one of the most namesake peaks in the Indian Heaven Volcanic Field. Geographical setting Sawtooth Mountain is the third highest peak the Indian Heaven Wilderness in Washington. On clear days hikers can see views of four nearby volcanoes: Mount Adams, Mount Hood, Mount St. Helens, and Mount Rainier from the Sawtooth Mountain Trail, which skirts the subalpine upper west side of Sawtooth Mountain. The shield volcano ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skamania County, Washington
Skamania County () is a county located in the U.S. state of Washington. As of the 2020 census, the population was 12,036. The county seat and largest incorporated city is Stevenson, although the Carson River Valley CDP is more populous. The county was founded in 1854 and derives its name from the Cascades Chinook word ''sk'mániak'', meaning "swift waters". Skamania County is included in the Portland-Vancouver- Hillsboro, OR-WA Metropolitan Statistical Area. History The area delineated by the future Washington state boundary began to be colonized at the start of the nineteenth century, both by Americans and British subjects. However, the majority of British exploration and interest in the land was due to the fur trade, whereas American settlers were principally seeking land for agriculture and cattle raising. The Treaty of 1818 provided for the region to be an Anglo-American condominium. During this period, the future Washington Territory was divided into two administrativ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eroded
Erosion is the action of surface processes (such as Surface runoff, water flow or wind) that removes soil, Rock (geology), rock, or dissolved material from one location on the Earth's crust#Crust, Earth's crust, and then sediment transport, transports it to another location where it is deposit (geology), deposited. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as ''physical'' or ''mechanical'' erosion; this contrasts with ''chemical'' erosion, where soil or rock material is removed from an area by Solvation, dissolution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres. Agents of erosion include rainfall; bedrock wear in rivers; coastal erosion by the sea and Wind wave, waves; glacier, glacial Plucking (glaciation), plucking, Abrasion (geology), abrasion, and scour; areal flooding; Aeolian processes, wind abrasion; groundwater processes; and Mass wasti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big Lava Bed
The Big Lava Bed, located in the Gifford Pinchot National Forest in the southwestern area of the State of Washington, originated from a 500-foot-deep crater in the northern center of the bed. The Big Lava Bed is the youngest feature of the Indian Heaven volcanic field. The 0.9-cubic kilometer lava flow erupted from the cinder cone about 8200 years ago. The lava flow traveled 13 km from the source crater. Lodgepole pine, alder, and other pioneer plants struggle to grow, seen sparsely growing between and amid towering rock piles, caves, and strange lava formations. Access into the interior of the lava bed is difficult, since there are no roads or trails crossing the lava field. Explorers who wish to venture deep within the lava flow are advised to choose their route carefully. Compasses are not always reliable, since local magnetic influences affect their magnetic performance in the vast expanse of rock. See also * Cascade Volcanoes * List of volcanoes in the United S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographic Coordinates
The geographic coordinate system (GCS) is a spherical or ellipsoidal coordinate system for measuring and communicating positions directly on the Earth as latitude and longitude. It is the simplest, oldest and most widely used of the various spatial reference systems that are in use, and forms the basis for most others. Although latitude and longitude form a coordinate tuple like a cartesian coordinate system, the geographic coordinate system is not cartesian because the measurements are angles and are not on a planar surface. A full GCS specification, such as those listed in the EPSG and ISO 19111 standards, also includes a choice of geodetic datum (including an Earth ellipsoid), as different datums will yield different latitude and longitude values for the same location. History The invention of a geographic coordinate system is generally credited to Eratosthenes of Cyrene, who composed his now-lost ''Geography'' at the Library of Alexandria in the 3rd century ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Heaven Volcanic Field And Mount Adams Volcanic Vicinity Digital Relief Map
Indian or Indians may refer to: Peoples South Asia * Indian people, people of Indian nationality, or people who have an Indian ancestor ** Non-resident Indian, a citizen of India who has temporarily emigrated to another country * South Asian ethnic groups, referring to people of the Indian subcontinent, as well as the greater South Asia region prior to the 1947 partition of India * Anglo-Indians, people with mixed Indian and British ancestry, or people of British descent born or living in the Indian subcontinent * East Indians, a Christian community in India Europe * British Indians, British people of Indian origin The Americas * Indo-Canadians, Canadian people of Indian origin * Indian Americans, American people of Indian origin * Indigenous peoples of the Americas, the pre-Columbian inhabitants of the Americas and their descendants ** Plains Indians, the common name for the Native Americans who lived on the Great Plains of North America ** Native Americans in the Uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanite, 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 planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, 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 volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, 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 flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary
The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ago to the present. The Quaternary Period is divided into two epochs: the Pleistocene (2.58 million years ago to 11.7 thousand years ago) and the Holocene (11.7 thousand years ago to today, although a third epoch, the Anthropocene, has been proposed but is not yet officially recognised by the ICS). The Quaternary Period is typically defined by the cyclic growth and decay of continental ice sheets related to the Milankovitch cycles and the associated climate and environmental changes that they caused. Research history In 1759 Giovanni Arduino proposed that the geological strata of northern Italy could be divided into four successive formations or "orders" ( it, quattro ordini). The term "quaternary" was introduced by Jules Desnoye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spatter Cones
Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and size of the fragments ejected during the eruption. Types of volcanic cones include stratocones, spatter cones, tuff cones, and cinder cones. Stratocone Stratocones are large cone-shaped volcanoes made up of lava flows, explosively erupted pyroclastic rocks, and igneous intrusives that are typically centered around a cylindrical vent. Unlike shield volcanoes, they are characterized by a steep profile and periodic, often alternating, explosive eruptions and effusive eruptions. Some have collapsed craters called calderas. The central core of a stratocone is commonly dominated by a central core of intrusive rocks that range from around to over several kilometers in diameter. This central core is surrounded by multiple generations of lava f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinder Cones
A cinder cone (or scoria cone) is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around a volcanic vent. The pyroclastic fragments are formed by explosive eruptions or lava fountains from a single, typically cylindrical, vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as either cinders, clinkers, or scoria around the vent to form a cone that often is symmetrical; with slopes between 30 and 40°; and a nearly circular ground plan. Most cinder cones have a bowl-shaped crater at the summit. Mechanics of eruption Cinder cones range in size from tens to hundreds of meters tall and often have a bowl-shaped crater at the summit. They are composed of loose pyroclastic material (cinder or scoria), which distinguishes them from ''spatter cones'', which are composed of agglomerated volcanic bombs. The pyroclastic material making up a cinder ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shield Volcanoes
A shield volcano is a type of volcano named for its low profile, resembling a warrior's shield lying on the ground. It is formed by the eruption of highly fluid (low viscosity) lava, which travels farther and forms thinner flows than the more viscous lava erupted from a stratovolcano. Repeated eruptions result in the steady accumulation of broad sheets of lava, building up the shield volcano's distinctive form. Shield volcanoes are found wherever fluid low-silica lava reaches the surface of a rocky planet. However, they are most characteristic of ocean island volcanism associated with hot spots or with continental rift volcanism. They include the largest volcanoes on earth, such as Tamu Massif and Mauna Loa. Giant shield volcanoes are found on other planets of the Solar System, including Olympus Mons on Mars and Sapas Mons on Venus. Etymology The term 'shield volcano' is taken from the German term ''Schildvulkan'', coined by the Austrian geologist Eduard Suess in 1888 and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Rainier
Mount Rainier (), indigenously known as Tahoma, Tacoma, Tacobet, or təqʷubəʔ, is a large active stratovolcano in the Cascade Range of the Pacific Northwest, located in Mount Rainier National Park about south-southeast of Seattle. With a summit elevation of , it is the highest mountain in the U.S. state of Washington and the Cascade Range, the most topographically prominent mountain in the contiguous United States, and the tallest in the Cascade Volcanic Arc. Due to its high probability of eruption in the near future, Mount Rainier is considered one of the most dangerous volcanoes in the world, and it is on the Decade Volcano list. The large amount of glacial ice means that Mount Rainier could produce massive lahars that could threaten the entire Puyallup River valley. According to the United States Geological Survey, "about 80,000 people and their homes are at risk in Mount Rainier's lahar-hazard zones." Between 1950 and 2018, 439,460 people climbed Mount Rainier. Appro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Hood
Mount Hood is a potentially active stratovolcano in the Cascade Volcanic Arc. It was formed by a subduction zone on the Pacific coast and rests in the Pacific Northwest region of the United States. It is located about east-southeast of Portland, on the border between Clackamas and Hood River counties. In addition to being Oregon's highest mountain, it is one of the loftiest mountains in the nation based on its prominence, and it offers the only year-round lift-served skiing in North America. The height assigned to Mount Hood's snow-covered peak has varied over its history. Modern sources point to three different heights: , a 1991 adjustment of a 1986 measurement by the U.S. National Geodetic Survey (NGS), based on a 1993 scientific expedition, and of slightly older origin. The peak is home to 12 named glaciers and snowfields. It is the highest point in Oregon and the fourth highest in the Cascade Range. Mount Hood is considered the Oregon volcano most likely to erupt, thoug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
