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Tukgahgo Mountain
Tukgahgo Mountain (TUG-a-ho) is a mountain in the Takshanuk Mountains in the U.S. state of Alaska with a peak elevation of . It is located in Haines Borough, to the southwest of Chilkoot Lake and to the southwest of Skagway. Geological investigations of the veins in the mountain have revealed silver, gold, platinum, and palladium mineralization, derived from mid-Cretaceous events. Geography Tukgahgo, an indigenous name given by the Tlingits, was recorded by geologist Eugene C. Robertson and published by the United States Geological Survey (USGS) in 1952. Tukgahgo is located southwest from Chilkoot, while Skagway is to the northeast. Vanderbilt Point is located west of Tukgahgo's summit. The head of Shakuseyi Creek is on the east slope of the mountain. Geology A 1991 geological sampling of a rock formation to the southwest of Tukgahgo Mountain on the northwest Chilly Peak (elevation was initially given the informal name "Chilly." The geologic formations of the area consis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haines Borough, Alaska
Haines Borough is a home rule, home-rule Borough (United States), borough located in the U.S. state, state of Alaska. As of the 2020 United States census, 2020 census, the population was 2,080, down from 2,508 in 2010. Geography The borough has a total area of , of which is land and (14.9%) is water. Adjacent boroughs and census areas * Municipality of Skagway Borough, Alaska – northeast * Juneau City and Borough, Alaska – southeast * Hoonah-Angoon Census Area, Alaska – south, west * Stikine Region, British Columbia – northwest, east National protected area * Tongass National Forest (part) ** Endicott River Wilderness Demographics At the 2000 United States Census, 2000 census there were 2,392 people, 991 households, and 654 families living in the borough. The population density was 0.88 people per square mile (0,34/km2). There were 1,419 housing units at an average density of 0.52 per square mile (0,20/km2). The Race and ethnicity in the United States Censu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tlingit People
The Tlingit ( or ; also spelled Tlinkit) are indigenous peoples of the Pacific Northwest Coast of North America. Their language is the Tlingit language (natively , pronounced ),"Lingít Yoo X'atángi: The Tlingit Language." ''Sealaska Heritage Institute.'' (retrieved 3 December 2009) in which the name means 'People of the Tides'.Pritzker, 208 The Russian name ' (, from a Sugpiaq-Alutiiq term ' for the worn by women) or the related German name ' may be encountered referring to the people in older historical literature, such as |
Strike And Dip
Strike and dip is a measurement convention used to describe the orientation, or attitude, of a planar geologic feature. A feature's strike is the azimuth of an imagined horizontal line across the plane, and its dip is the angle of inclination measured downward from horizontal. They are used together to measure and document a structure's characteristics for study or for use on a geologic map. A feature's orientation can also be represented by dip and dip direction, using the azimuth of the dip rather than the strike value. Linear features are similarly measured with trend and plunge, where "trend" is analogous to dip direction and "plunge" is the dip angle. Strike and dip are measured using a compass and a clinometer. A compass is used to measure the feature's strike by holding the compass horizontally against the feature. A clinometer measures the features dip by recording the inclination perpendicular to the strike. These can be done separately, or together using a tool such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of 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 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 geologic maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can blur the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz Vein
In geology, a vein is a distinct sheetlike body of crystallized minerals within a rock. Veins form when mineral constituents carried by an aqueous solution within the rock mass are deposited through precipitation. The hydraulic flow involved is usually due to hydrothermal circulation. Veins are classically thought of as being the ones in the body not the rock veins and arteries planar fractures in rocks, with the crystal growth occurring normal to the walls of the cavity, and the crystal protruding into open space. This certainly is the method for the formation of some veins. However, it is rare in geology for significant open space to remain open in large volumes of rock, especially several kilometers below the surface. Thus, there are two main mechanisms considered likely for the formation of veins: ''open-space filling'' and ''crack-seal growth''. Open space filling Open space filling is the hallmark of epithermal vein systems, such as a stockwork, in greisens or in c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pluton
In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and compositions, illustrated by examples like the Palisades Sill of New York and New Jersey; the Henry Mountains of Utah; the Bushveld Igneous Complex of South Africa; Shiprock in New Mexico; the Ardnamurchan intrusion in Scotland; and the Sierra Nevada Batholith of California. Because the solid country rock into which magma intrudes is an excellent insulator, cooling of the magma is extremely slow, and intrusive igneous rock is coarse-grained (phaneritic). Intrusive igneous rocks are classified separately from extrusive igneous rocks, generally on the basis of their mineral content. The relative amounts of quartz, alkali feldspar, plagioclase, and feldspathoid is particularly important in classifying intrusive igneous rocks. Intrusions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Kashagnak
Mount is often used as part of the name of specific mountains, e.g. Mount Everest. Mount or Mounts may also refer to: Places * Mount, Cornwall, a village in Warleggan parish, England * Mount, Perranzabuloe, a hamlet in Perranzabuloe parish, Cornwall, England * Mounts, Indiana, a community in Gibson County, Indiana, United States People * Mount (surname) * William L. Mounts (1862–1929), American lawyer and politician Computing and software * Mount (computing), the process of making a file system accessible * Mount (Unix), the utility in Unix-like operating systems which mounts file systems Displays and equipment * Mount, a fixed point for attaching equipment, such as a hardpoint on an airframe * Mounting board, in picture framing * Mount, a hanging scroll for mounting paintings * Mount, to display an item on a heavy backing such as foamcore, e.g.: ** To pin a biological specimen, on a heavy backing in a stretched stable position for ease of dissection or display ** To p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monzonite
Monzonite is an igneous intrusive rock, formed by slow cooling of underground magma that has a moderate silica content and is enriched in alkali metal oxides. Monzonite is composed mostly of plagioclase and alkali feldspar. Syenodiorite is an obsolescent term for monzonite or for monzodiorite.Le Maitre, R.W., ''Igneous Rocks: A Classification and Glossary of Terms'' Cambridge University Press, 2nd ed, pp. 113 Larvikite is a particular form of monzonite. Description Monzonite is a coarse-grained (phaneritic) igneous rock. Such rocks are classified by their relative percentages of quartz, plagioclase, alkali feldspar, and feldspathoid (the QAPF classification). Monzonite is defined as rock having less than 5% quartz in its QAPF fraction and in which alkali feldspar makes up between 35% and 65% of the total feldspar content. If quartz constitutes greater than 5% of the QAPF fraction, the rock is termed a quartz monzonite, while if feldspathoids are present as up to 10% of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granodiorite
Granodiorite () is a coarse-grained (phaneritic) intrusive igneous rock similar to granite, but containing more plagioclase feldspar than orthoclase feldspar. The term banatite is sometimes used informally for various rocks ranging from granite to diorite, including granodiorite. Composition According to the QAPF diagram, granodiorite has a greater than 20% quartz by volume, and between 65% and 90% of the feldspar is plagioclase. A greater amount of plagioclase would designate the rock as tonalite. Granodiorite is felsic to intermediate in composition. It is the intrusive igneous equivalent of the extrusive igneous dacite. It contains a large amount of sodium (Na) and calcium (Ca) rich plagioclase, potassium feldspar, quartz, and minor amounts of muscovite mica as the lighter colored mineral components. Biotite and amphiboles often in the form of hornblende are more abundant in granodiorite than in granite, giving it a more distinct two-toned or overall darker appearan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diorite
Diorite ( ) is an intrusive igneous rock formed by the slow cooling underground of magma (molten rock) that has a moderate content of silica and a relatively low content of alkali metals. It is intermediate in composition between low-silica (mafic) gabbro and high-silica ( felsic) granite. Diorite is found in mountain-building belts (''orogens'') on the margins of continents. It has the same composition as the fine-grained volcanic rock, andesite, which is also common in orogens. Diorite has been used since prehistoric times as decorative stone. It was used by the Akkadian Empire of Sargon of Akkad for funerary sculptures, and by many later civilizations for sculptures and building stone. Description Diorite is an intrusive igneous rock composed principally of the silicate minerals plagioclase feldspar (typically andesine), biotite, hornblende, and sometimes pyroxene. The chemical composition of diorite is intermediate, between that of mafic gabbro and felsic grani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hornblende
Hornblende is a complex inosilicate series of minerals. It is not a recognized mineral in its own right, but the name is used as a general or field term, to refer to a dark amphibole. Hornblende minerals are common in igneous and metamorphic rocks. The general formula is . Physical properties Hornblende has a hardness of 5–6, a specific gravity of 3.0 to 3.6, and is typically an opaque green, dark green, brown, or black color. It tends to form slender prismatic to bladed crystals, diamond-shaped in cross-section, or is present as irregular grains or fibrous masses. Its planes of cleavage intersect at 56° and 124° angles. Hornblende is most often confused with the pyroxene series and biotite mica, which are also dark minerals found in granite and charnockite. Pyroxenes differ in their cleavage planes, which intersect at 87° and 93°. Hornblende is an inosilicate (chain silicate) mineral, built around double chains of silica tetrahedra. These chains extend the length of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roof Pendant
In structural geology, a roof pendant, also known as a pendant, is a mass of country rock that projects downward into and is entirely surrounded by an igneous intrusion such as a batholith or other pluton. In lay terminology sometimes "rock hat" is used. A roof pendant is an erosional remnant that was created by the removal of the overlying country rock that formed the roof of the igneous intrusion that encloses it. If this downward protruding mass of roof rock still has a connection to the main, surrounding mass of country rock, they are known by structural geologists as either ''septa'' or ''screens.''U.S. Bureau of Mines Staff (1996) ''Dictionary of Mining, Mineral, & Related Terms.'' Report SP-96-1, U.S. Department of Interior, U.S. Bureau of Mines, Washington, D.C.Neuendorf, KKE, JP Mehl, Jr., and JA Jackson, eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. Best, MG (2003) ''Igneous and metamorphic petrology, 2nd e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
