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Sonomia Terrane
The Sonomia Terrane is a geologic crustal block known as a "terrane" whose remnants today lie in northwest Nevada. The terrane acquired its name from the Sonoma Range in that region. The Sonomia Terrane is associated with the Golconda Thrust, a structure named for its proximity to the town of Golconda, Nevada. The Sonoma orogeny was caused by the accretion of the Sonomia microcontinent onto western North America during the mid-Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period .... References Geology of Nevada Terranes {{US-geology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustal Block
Fault blocks are very large blocks of rock, sometimes hundreds of kilometres in extent, created by tectonic and localized stresses in Earth's crust. Large areas of bedrock are broken up into blocks by faults. Blocks are characterized by relatively uniform lithology. The largest of these fault blocks are called crustal blocks. Large crustal blocks broken off from tectonic plates are called terranes. Those terranes which are the full thickness of the lithosphere are called microplates. Continent-sized blocks are called variously ''microcontinents, continental ribbons, H-blocks, extensional allochthons and outer highs.'' Because most stresses relate to the tectonic activity of moving plates, most motion between blocks is horizontal, that is parallel to the Earth's crust by strike-slip faults. However vertical movement of blocks produces much more dramatic results. Landforms (mountains, hills, ridges, lakes, valleys, etc.) are sometimes formed when the faults have a large vert ... [...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 own distinctive geologic history, which is different from that of 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. Older usage of ''terrane'' simply described a series of related rock formations or an area having a preponderance of a particular rock or rock groups. Overview A tectonostratigraphic terrane is not necessarily an independent microplate in origin, since it may not contain the full thickness ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nevada
Nevada ( ; ) is a U.S. state, state in the Western United States, Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the List of U.S. states and territories by area, 7th-most extensive, the List of U.S. states and territories by population, 32nd-most populous, and the List of U.S. states and territories by population density, 9th-least densely populated of the U.S. states. Nearly three-quarters of Nevada's people live in Clark County, Nevada, Clark County, which contains the Las Vegas–Paradise, NV MSA, Las Vegas–Paradise metropolitan area, including three of the state's four largest incorporated cities. Nevada's capital is Carson City, Nevada, Carson City. Las Vegas is the largest city in the state. Nevada is officially known as the "Silver State" because of the importance of silver to its history and economy. It is also known as the "Battle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonoma Range
The Sonoma Range is a small mountain range in northwest Nevada, USA. It lies just south of the Humboldt River between Winnemucca and Golconda. It is one of the many ranges of the basin and range geologic province of the Great Basin. Sonoma Peak is the highest mountain in the range at (). Its summit is located at . The range's name is a transfer from Sonoma County Sonoma County () is a county (United States), county located in the U.S. state of California. As of the 2020 United States Census, its population was 488,863. Its county seat and largest city is Santa Rosa, California, Santa Rosa. It is to the n ... in California. Notes Mountain ranges of Nevada Range, Sonoma Mountain ranges of Humboldt County, Nevada Mountain ranges of Pershing County, Nevada {{PershingCountyNV-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golconda Thrust
The Golconda Thrust is a major oceanic terrane that was thrust over central and northern Nevada, North America, in possibly sometime between the Late Permian and the late Jurassic. It is considered equivalent to the Tobin thrust fault. It contains the Havallah sequence. Timing the Golconda Thrust The time of the Golconda Thrust is not perfectly clear, and it may pre-date the Sonoma orogeny. Other references suspect it appears to have thrust during the Sonoma orogeny. See also * Geology of Nevada * Golconda, Nevada * Sonomia Terrane The Sonomia Terrane is a geologic crustal block known as a "terrane" whose remnants today lie in northwest Nevada. The terrane acquired its name from the Sonoma Range in that region. The Sonomia Terrane is associated with the Golconda Thrust, a s ... References External links and references One link {{geology-stub Geology of Nevada Terranes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golconda, Nevada
Golconda is a census-designated place in southeastern Humboldt County, Nevada, United States. As of the 2010 census it had a population of 214. It is located along Interstate 80 on the Humboldt River in the northwestern part of the state. Golconda has a post office, which has been in operation since 1869. History Golconda was founded in 1869. The community was named for the ancient diamond mining center of Golkonda in India. The settlement had its start when discovery of copper, silver, gold, and lead brought entrepreneurs who opened mines and mills in the district. The town was a diverse society including both native-born European Americans as well as other groups including individuals of French, Portuguese, Paiute, and Chinese descent who all lived and worked in the small community. During 1898-1910, the town had a train depot, several hotels, a school, businesses, newspapers, and two brothels. Its population peaked at about six hundred in 1907-08. Although boosters predict ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonoma Orogeny
The Sonoma orogeny was a period of mountain building in western North America. The exact age and structure of the Sonoma orogeny is controversial. The orogeny is generally thought to have occurred during the Permian / Triassic transition, around 250 million years ago, following the Late Devonian Antler orogeny. The Sonoma orogeny was one of a sequence of accretionary events along the Cordilleran margin, possibly caused by the closure of the basin between the island arc of Sonomia and the North American continent. Evidence of this event has been reported throughout western North America, but most distinctly in northwest Nevada. The orogeny was named by Silberling and Roberts, who identified it with the Havallah Formation, originally thought to date to the Pennsylvanian and Permian ages but has since been revised to include rocks of Late Devonian and Mississippian age. Some geologists dispute whether convergent plate tectonics produced the Sonoma orogeny. Stratigraphy The Hava ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accretion (geology)
Accretion, in geology, is a process by which material is added to a tectonic plate at a subduction zone, frequently on the edge of existing continental landmasses. The added material may be sediment, volcanic arcs, seamounts, oceanic crust or other igneous features. Description Accretion involves the addition of material to a tectonic plate via subduction, the process by which one plate is forced under the other when two plates collide. The plate which is being forced down, the subducted plate, is pushed against the upper, over-riding plate. Sediment on the ocean floor of the subducting plate is often scraped off as the plate descends. This accumulated material is called an accretionary wedge (or accretionary prism), which is pushed against and attaches to the upper plate. In addition to accumulated ocean sediments, volcanic island arcs or seamounts present on the subducting plate may be amalgamated onto existing continental crust on the upper plate, increasing the continental ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continental Fragment
Continental crustal fragments, partly synonymous with microcontinents, are pieces of continents that have broken off from main continental masses to form distinct islands that are often several hundred kilometers from their place of origin. Causes Continental fragments and microcontinent crustal compositions are very similar to those of regular continental crust. The rifting process that caused the continental fragments to form most likely impacts their layers and overall thickness along with the addition of mafic intrusions to the crust. Studies have determined that the average crustal thickness of continental fragments is approximately . The sedimentary layer of continental fragments can be up to thick and can overlay two to three crustal layers. Continental fragments have an average crustal density of which is very similar to that of typical continental crust. Strike-slip fault zones cause the fragmentation of microcontinents. The zones link the extensional zones where c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triassic
The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the chief terrestrial vertebrates during this time. A specialized subgroup of archo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Nevada
The geology of Nevada began to form in the Proterozoic at the western margin of North America. Terranes accreted to the continent as a marine environment dominated the area through the Paleozoic and Mesozoic periods. Intense volcanism, the horst and graben landscape of the Basin and Range Province originating from the Farallon Plate, and both glaciers and valley lakes have played important roles in the region throughout the past 66 million years. Geologic history, stratigraphy, and tectonics The oldest rocks in Nevada are in the East Humboldt Range in the northeast, with lead isotope data suggesting an age of 2.5 billion years, at the boundary of the Archean and Proterozoic. Metamorphic and igneous rocks formed 1.7 billion years ago underlie Clark County and the populous areas around Las Vegas. The region was part of the supercontinent Rodinia one billion years ago, situated at the equator. The continent rifted apart between 700 and 600 million years ago. No continental rocks ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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