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Solitario
The Solitario (''El Solitario'') is a large geologic formation in Big Bend Ranch State Park in West Texas. When viewed from above, it suggests an impact crater; though it is actually the eroded remains of a laccolith. The approximate center of the Solitario is located east southeast of Presidio, Texas, just west of the line dividing Brewster County, Texas and Presidio County, Texas. The formation covers a circular area of approximately . The geology of the Solitario is complex. In 1988 the state of Texas purchased the property containing the Solitario and created Big Bend Ranch State Park. The formation lies in the Chihuahuan Desert ecoregion of the United States. Geology The Solitario is a structural dome developed in Paleozoic and Cretaceous rocks above an Eocene granite laccolith intrusion. The dome is associated with radial rhyolite to trachyte dikes and sills and erupted ash flow tuffs. The 16 km diameter dome contains a 6 by 2 km volcanic caldera filled with col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solitario Peak
The Solitario (''El Solitario'') is a large geologic formation in Big Bend Ranch State Park (Texas), Big Bend Ranch State Park in West Texas. When viewed from above, it suggests an impact crater; though it is actually the eroded remains of a laccolith. The approximate center of the Solitario is located east southeast of Presidio, Texas, just west of the line dividing Brewster County, Texas and Presidio County, Texas. The formation covers a circular area of approximately . The geology of the Solitario is complex. In 1988 the state of Texas purchased the property containing the Solitario and created Big Bend Ranch State Park. The formation lies in the Chihuahuan Desert ecoregion of the United States. Geology The Solitario is a structural Dome (geology), dome developed in Paleozoic and Cretaceous rocks above an Eocene granite laccolith intrusion. The dome is associated with radial rhyolite to trachyte Dike (geology), dikes and Sill (geology), sills and erupted Volcanic ash, ash flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big Bend Ranch State Park (Texas)
Big Bend Ranch State Park is a state park located on the Rio Grande in Brewster and Presidio counties, Texas. It is the largest state park in Texas. The closest major town is Presidio, Texas, where the state park's head office is located."Big Bend Ranch State Park", ''Texas Parks and Wildlife Department'' Retrieved November 5, 2008. It includes Colorado Canyon. Features 
Big Bend Ranch is located adjacent to
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Laccolith
A laccolith is a body of intrusive rock with a dome-shaped upper surface and a level base, fed by a conduit from below. A laccolith forms when magma (molten rock) rising through the Earth's crust begins to spread out horizontally, prying apart the host rock strata. The pressure of the magma is high enough that the overlying strata are forced upward, giving the laccolith its dome-like form. Over time, erosion can expose the solidified laccolith, which is typically more resistant to weathering than the host rock. The exposed laccolith then forms a hill or mountain. The Henry Mountains of Utah, US, are an example of a mountain range composed of exposed laccoliths. It was here that geologist Grove Karl Gilbert carried out pioneering field work on this type of intrusion. Laccolith mountains have since been identified in many other parts of the world. Description A laccolith is a type of igneous intrusion, formed when magma forces its way upwards through the Earth's crust b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chihuahuan Desert
The Chihuahuan Desert ( es, Desierto de Chihuahua, ) is a desert ecoregion designation covering parts of northern Mexico and the southwestern United States. It occupies much of far West Texas, the middle to lower Rio Grande Valley and the lower Pecos Valley in New Mexico, and a portion of southeastern Arizona, as well as the central and northern portions of the Mexican Plateau. It is bordered on the west by the Sonoran Desert, the Colorado Plateau, and the extensive Sierra Madre Occidental range, along with northwestern lowlands of the Sierra Madre Oriental range. Its largest, continual expanse is located in Mexico, covering a large portion of the state of Chihuahua, along with portions of Coahuila, north-eastern Durango, the extreme northern part of Zacatecas, and small western portions of Nuevo León. With an area of about , it is the largest desert in North America. The desert is fairly young, existing for only 8000 years. Geography There are several larger mountain ranges ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ouachita Orogeny
The Ouachita orogeny was a mountain-building event that resulted in the folding and faulting of strata currently exposed in the Ouachita Mountains. The more extensive Ouachita system extends from the current range in Arkansas and Oklahoma southeast to the Black Warrior Basin in Alabama and to the southwest through the Llano, Marathon, and Solitario uplifts in Texas on into Coahuila and Chihuahua in Mexico. The Ouachita System Pre-collision formations The region during the early Paleozoic lay off the coast of the southern portion of Laurentia, in what is now the southern United States. Laurentia straddled the equator at the time and the Rheic Ocean was to the south of Laurentia. Through the Ordovician, Silurian, Devonian, and early Carboniferous, marine sedimentation left extensive deposits of black shale, quartzose sandstone, and chert beds. During the Mississippian, a flysch sequence with dark shales and graywackes was deposited. Lenses of silicic tuff exist as evidenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laccolith
A laccolith is a body of intrusive rock with a dome-shaped upper surface and a level base, fed by a conduit from below. A laccolith forms when magma (molten rock) rising through the Earth's crust begins to spread out horizontally, prying apart the host rock strata. The pressure of the magma is high enough that the overlying strata are forced upward, giving the laccolith its dome-like form. Over time, erosion can expose the solidified laccolith, which is typically more resistant to weathering than the host rock. The exposed laccolith then forms a hill or mountain. The Henry Mountains of Utah, US, are an example of a mountain range composed of exposed laccoliths. It was here that geologist Grove Karl Gilbert carried out pioneering field work on this type of intrusion. Laccolith mountains have since been identified in many other parts of the world. Description A laccolith is a type of igneous intrusion, formed when magma forces its way upwards through the Earth's crust b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sill (geology)
In geology, a sill is a tabular sheet intrusion that has intruded between older layers of sedimentary rock, beds of volcanic lava or tuff, or along the direction of foliation in metamorphic rock. A ''sill'' is a ''concordant intrusive sheet'', meaning that a sill does not cut across preexisting rock beds. Stacking of sills builds a sill complex . and a large magma chamber at high magma flux. In contrast, a dike is a discordant intrusive sheet, which does cut across older rocks. Sills are fed by dikes, except in unusual locations where they form in nearly vertical beds attached directly to a magma source. The rocks must be brittle and fracture to create the planes along which the magma intrudes the parent rock bodies, whether this occurs along preexisting planes between sedimentary or volcanic beds or weakened planes related to foliation in metamorphic rock. These planes or weakened areas allow the intrusion of a thin sheet-like body of magma paralleling the existing bedding pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Ash
Volcanic ash consists of fragments of rock, mineral crystals, and volcanic glass, created during volcano, volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used to refer to all explosive eruption products (correctly referred to as ''tephra''), including particles larger than 2 mm. Volcanic ash is formed during explosive volcanic eruptions when dissolved gases in magma expand and escape violently into the atmosphere. The force of the gases shatters the magma and propels it into the atmosphere where it solidifies into fragments of volcanic rock and glass. Ash is also produced when magma comes into contact with water during phreatomagmatic eruptions, causing the water to explosively flash to steam leading to shattering of magma. Once in the air, ash is transported by wind up to thousands of kilometres away. Due to its wide dispersal, ash can have a number of impacts on society, including animal a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuff
Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. Rock that contains greater than 75% ash is considered tuff, while rock containing 25% to 75% ash is described as tuffaceous (for example, ''tuffaceous sandstone''). Tuff composed of sandy volcanic material can be referred to as volcanic sandstone. Tuff is a relatively soft rock, so it has been used for construction since ancient times. Because it is common in Italy, the Romans used it often for construction. The Rapa Nui people used it to make most of the ''moai'' statues on Easter Island. Tuff can be classified as either igneous or sedimentary rock. It is usually studied in the context of igneous petrology, although it is sometimes described using sedimentological terms. Tuff is often erroneously called tufa in guidebooks and in television programmes. Volcanic ash The material that is expelled in a volcanic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breccia
Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix. The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of different origins, as indicated by the named types including sedimentary breccia, tectonic breccia, igneous breccia, impact breccia, and hydrothermal breccia. A megabreccia is a breccia composed of very large rock fragments, sometimes kilometers across, which can be formed by landslides, impact events, or caldera collapse. Types Breccia is composed of coarse rock fragments held together by cement or a fine-grained matrix. Like conglomerate, breccia contains at least 30 percent of gravel-sized particles (particles over 2mm in size), but it is distinguished from conglomerate because the rock fragments have sharp edges that have not been worn down. These indicate that the gravel was deposited very close to its source area, since otherwise th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brewster County, Texas
Brewster County is a county located in the U.S. state of Texas. It is in West Texas and its county seat (and only city) is Alpine. It is one of the nine counties that comprise the Trans-Pecos region, and borders Mexico. Brewster County is the largest county by area in the state - at it is over three times the size of the state of Delaware, and more than bigger than Connecticut. As of the 2020 census, the population was 9,546. The county is named for Colonel Henry Percy Brewster, a Secretary of War for the Republic of Texas. History Native Americans Paleo-Indian hunter-gatherers existed in the region at least 9000 years ago. Mescalaro Apaches emerged later and conducted raids that discouraged settlers. Between 1779 and 1787, Col. Juan de Ugalde drove the Mescalaros back north across the Rio Grande and into the Chisos Mountains. The three leading Mescalero chiefs, Patula Grande, Quemado, and Zapato Tuerto, agreed in March 1789 to submit to Spanish rule. Comanche raidi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or underwater, usually at temperatures from . The volcanic rock resulting from subsequent cooling is also often called ''lava''. A lava flow is an outpouring of lava during an effusive eruption. (An explosive eruption, by contrast, produces a mixture of volcanic ash and other fragments called tephra, not lava flows.) The viscosity of most lava is about that of ketchup, roughly 10,000 to 100,000 times that of water. Even so, lava can flow great distances before cooling causes it to solidify, because lava exposed to air quickly develops a solid crust that insulates the remaining liquid lava, helping to keep it hot and inviscid enough to continue flowing. The word ''lava'' comes from Italian and is probably derived from the Latin word ''labes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
