A batholith (from Greek bathos, depth + lithos, rock) is a large emplacement of igneous intrusive (also called plutonic) rock that forms from cooled magma deep in the Earth's crust. Igneous rocks (etymology from Latin ignis, fire are rocks formed by solidification of cooled Magma (molten rock In Geology, an intrusion is a body of Igneous rock that has Crystallized from molten Magma below the surface of the Earth. Magma (Plurals magmas and magmata) is molten rock that sometimes forms beneath the surface of the Earth (or any other Terrestrial planet In Geology, a crust is the outermost solid shell of a planet or moon Batholiths are almost always made mostly of felsic or intermediate rock-types, such as granite, quartz monzonite, or diorite (see also granite dome). Felsic is a term used in Geology to refer to Silicate minerals, Magma, and rocks which are enriched in the lighter elements such as Silicon Granite (ˈɡrænɪt is a common and widely occurring type of intrusive, Felsic, igneous rock. Quartz monzonite (or adamellite) is an intrusive Igneous rock that has an approximately equal proportion of Orthoclase and Plagioclase Diorite (ˈdaɪəraɪt is a grey to dark grey intermediate intrusive Igneous rock composed principally of Plagioclase Feldspar (typically A granite dome is a dome of Granite, formed by exfoliation. Formation Granite forms Plutons of Igneous rock
Although they may appear uniform, batholiths are in fact structures with complex histories and compositions. They are composed of multiple masses, or plutons, bodies of igneous rock of irregular dimensions (typically at least several kilometers) that can be distinguished from adjacent igneous rock by some combination of criteria including age, composition, texture, or mappable structures. Individual plutons are crystallized from magma that traveled toward the surface from a zone of partial melting near the base of the Earth's crust.
Traditionally, these plutons have been considered to form by ascent of relatively buoyant magma in large masses called plutonic diapirs. In Physics, buoyancy ( BrE IPA: /ˈbɔɪənsi/ is the upward Force on an object produced by the surrounding liquid or gas in which it is A diapir (ˈdaɪəpɪər) ( French, from Greek diapeirein, to pierce through is an Intrusion caused by Buoyancy and Pressure Because the diapirs are liquefied and very hot, they tend to rise through the surrounding country rock, pushing it aside and partially melting it. Country rock is a geological term meaning the rock native to an area Most diapirs do not reach the surface to form volcanoes, but instead slow down, cool and usually solidify 5 to 30 kilometers underground as plutons (hence the use of the word pluton; in reference to the Roman god of the underworld Pluto). Plate tectonics and hotspots Divergent plate boundaries At the Ancient Rome was a Civilization that grew out of a small agricultural community founded on the Italian Peninsula as early as the 10th century BC Pluto was the Roman god of the underworld known in Latin as Tertius the counterpart of the Greek Hades. It has also been proposed that plutons commonly are formed not by diapiric ascent of large magma diapirs, but rather by aggregation of smaller volumes of magma that ascended as dikes.
A batholith is formed when many plutons converge together to form a huge expanse of granitic rock. Some batholiths are mammoth, paralleling past and present subduction zones and other heat sources for hundreds of kilometers in continental crust. In Geology, a subduction zone is an area on Earth where two tectonic plates meet and move towards one another with one sliding underneath the other The continental crust is the layer of granitic, Sedimentary, and Metamorphic rocks which form the Continents and the areas of shallow seabed One such batholith is the Sierra Nevada Batholith, which is a continuous granitic formation that forms much of the Sierra Nevada in California. The Sierra Nevada Batholith is a large Batholith which forms the core of the Sierra Nevada mountain range in California, USA, exposed at The Sierra Nevada ( Spanish for "Snowy Range" is a Mountain range located in the U California ( is a US state on the West Coast of the United States, along the Pacific Ocean. An even larger batholith, found predominantly in the Coast Mountains of western Canada, extends for 1,800 kilometers and reaches into southeastern Alaska, which is called the Coast Plutonic Complex. The Coast Mountains are a Mountain range of the Pacific Cordillera, running along the north western shore of the North American continent extending south Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page Alaska ( Аляска Alyaska) is a state in the United States of America, in the northwest of the North American continent
There is also an important geographic usage of the term batholith. For a geographer, a batholith is an exposed area of mostly continuous plutonic rock that covers an area larger than 100 square kilometers. Areas smaller than 100 kilometers are called stocks. However, the majority of batholiths visible at the surface (via outcroppings) have areas far greater than 100 square kilometers. These areas are exposed to the surface through the process of erosion accelerated by continental uplift acting over many tens of millions to hundreds of millions of years. Erosion is the carrying away or displacement of solids ( Sediment, Soil, rock and other particles usually by the agents of currents such as wind Orogeny (Greek for "mountain generating" is the process of natural Mountain building and may be studied as a tectonic structural event as a geographical event and This process has removed several tens of kilometers of overlying rock in many areas, exposing the once deeply buried batholiths.
Batholiths exposed at the surface are also subjected to huge pressure differences between their former homes deep in the earth and their new homes at or near the surface. As a result, their crystal structure expands slightly and over time. In Mineralogy and Crystallography, a crystal structure is a unique arrangement of Atoms in a Crystal. This manifests itself by a form of mass wasting called exfoliation. Mass wasting, also known as slope movement, is the geomorphic process by which Soil, Regolith, and rock move downslope under This form of erosion causes convex and relatively thin sheets of rock to slough off the exposed surfaces of batholiths (a process accelerated by frost wedging). The result is fairly clean and rounded rock faces. A well-known example of the result of this process is Half Dome, which located in Yosemite Valley. Half Dome is a Granite dome in Yosemite National Park, located at the eastern end of Yosemite Valley — possibly Yosemite's most familiar sight Yosemite Valley (joʊˈsɛməti yoh-SEM-it-ee) is a world-famous scenic location in the Sierra Nevada mountains of California.
See also
References
- Plummer, McGeary, Carlson, Physical Geology, Eight Edition (McGraw-Hill: Boston, 1999) pages 61-63 ISBN 0-697-37404-1
- Glazner, Bartley, Coleman, Gray, Taylor, Are plutons assembled over millions of years by amalgamation from small magma chambers?, GSA Today: Vol. A granite dome is a dome of Granite, formed by exfoliation. Formation Granite forms Plutons of Igneous rock A laccolith is an Igneous intrusion (or concordant Pluton) that has been injected between two layers of Sedimentary rock. A dike or dyke in Geology is a type of Sheet intrusion referring to any geologic body that cuts Discordantly ' across planar In Geology, a sill is a tabular Pluton that has intruded between older layers of Sedimentary rock, beds of Volcanic A volcanic plug, also called a volcanic neck or lava neck, is a volcanic landform created when Lava hardens within a Vent on In Geology, an intrusion is a body of Igneous rock that has Crystallized from molten Magma below the surface of the Earth. 14, No. 4, pp. 4–11
External links
Dapyx Software network: MP3 Explorer | Ebook Manager | Zenithic