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Synform
In structural geology, a syncline is a fold with younger layers closer to the center of the structure, whereas an anticline is the inverse of a syncline. A synclinorium (plural synclinoriums or synclinoria) is a large syncline with superimposed smaller folds. Synclines are typically a downward fold (synform), termed a synformal syncline (i.e. a trough), but synclines that point upwards can be found when strata have been overturned and folded (an antiformal syncline). Characteristics On a geologic map, synclines are recognized as a sequence of rock layers, with the youngest at the fold's center or ''hinge'' and with a reverse sequence of the same rock layers on the opposite side of the hinge. If the fold pattern is circular or elongate, the structure is a basin. Folds typically form during crustal deformation as the result of compression that accompanies orogenic mountain building. Notable examples * Powder River Basin, Wyoming, US * Sideling Hill roadcut along Interstate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fold (geology)
In structural geology, a fold is a stack of originally planar surfaces, such as sedimentary strata, that are bent or curved during permanent deformation. Folds in rocks vary in size from microscopic crinkles to mountain-sized folds. They occur as single isolated folds or in periodic sets (known as ''fold trains''). Synsedimentary folds are those formed during sedimentary deposition. Folds form under varied conditions of stress, pore pressure, and temperature gradient, as evidenced by their presence in soft sediments, the full spectrum of metamorphic rocks, and even as primary flow structures in some igneous rocks. A set of folds distributed on a regional scale constitutes a fold belt, a common feature of orogenic zones. Folds are commonly formed by shortening of existing layers, but may also be formed as a result of displacement on a non-planar fault (''fault bend fold''), at the tip of a propagating fault (''fault propagation fold''), by differential compaction or due to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southland Syncline
The Southland Syncline is a major geological structure located in the Southland Region of New Zealand's South Island. The syncline folds the Mesozoic greywackes of the Murihiku Terrane. The northern limb of the fold is steep to overturned, while the southern limb dips shallowly to the northeast. The axial plan dips to the northeast and the axis plunges to the southeast. The Murihiku Terrane is formed predominantly from Permian to Jurassic sedimentary rocks with minor igneous intrusions, and is marked by prominent strike ridges particularly on its northern limb due to the steeper dip. These are created from the erosion of alternating strata of sandstone and mudstone. The northern edge of this fold system is marked by the Murihiku Escarpment, at the southern extreme of the Waimea Plains. Many of the names of stages and epochs in the Permian, Triassic, and Jurassic periods in the New Zealand geologic time scale are named for places within or close to the Southland Syncline and Murihi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its west by Nevada. Utah also touches a corner of New Mexico in the southeast. Of the fifty U.S. states, Utah is the 13th-largest by area; with a population over three million, it is the 30th-most-populous and 11th-least-densely populated. Urban development is mostly concentrated in two areas: the Wasatch Front in the north-central part of the state, which is home to roughly two-thirds of the population and includes the capital city, Salt Lake City; and Washington County in the southwest, with more than 180,000 residents. Most of the western half of Utah lies in the Great Basin. Utah has been inhabited for thousands of years by various indigenous groups such as the ancient Puebloans, Navajo and Ute. The Spanish were the first Europe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Provo Canyon
Provo Canyon is located in unincorporated Utah County and Wasatch County, Utah. Provo Canyon runs between Mount Timpanogos on the north and Mount Cascade on the south. The canyon extends from Orem on the west end to Heber City on the east. Provo Canyon is situated to the east of Utah Valley and grants access to the valleys and Uinta Basin regions that lie beyond the Wasatch front. Through forces of erosion, the Provo River has carved out the canyon over time. Attractions in Provo Canyon include Vivian Park, Sundance, and Bridal Veil Falls. The canyon is known for both its natural attractions and practical uses. Deer Creek Reservoir serves as water storage for Salt Lake and Utah Valleys. Provo Canyon has served as a route of transportation between the valleys to the east and west of the Wasatch mountain range. The Heber Valley Historic Railroad operates passenger trains through the canyon. U.S. route 189 connects Provo and Orem with Heber City to the east. In early settlement, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hondo Group
The Hondo Group is a group of geologic formations that crops out in most of the Precambrian-cored uplifts of northern New Mexico. Detrital zircon geochronology gives a maximum age for the lower Hondo Group of 1765 to 1704 million years ( Mya), corresponding to the Statherian period. Geology The Hondo Group consists of a lower very clean quartzite (the Ortega Formation) and upper schists, quartzites, and slates. The total thickness is about .Montgomery 1953 The upper section is absent in the Tusas Mountains, where the Hondo Group is essentially synonymous with the Ortega Formation. The upper section is assigned to the Rinconada Formation in the Picuris Mountains. The most complete section is in the northern Picuris Mountains, where the Hondo Group fills an overturned syncline. Detrital zircon geochronology establishes an age for the lower Hondo Group of 1765 to 1704 Mya.Jones ''et al.'' 2011 The Pilar and Piedra Lumbre Formations were originally included in the Hondo Group. H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Mexico
) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Keres, Zuni , Governor = , Lieutenant Governor = , Legislature = New Mexico Legislature , Upperhouse = Senate , Lowerhouse = House of Representatives , Judiciary = New Mexico Supreme Court , Senators = * * , Representative = * * * , postal_code = NM , TradAbbreviation = N.M., N.Mex. , area_rank = 5th , area_total_sq_mi = 121,591 , area_total_km2 = 314,915 , area_land_sq_mi = 121,298 , area_land_km2 = 314,161 , area_water_sq_mi = 292 , area_water_km2 = 757 , area_water_percent = 0.24 , population_as_of = 2020 , population_rank = 36th , 2010Pop = 2,117,522 , population_density_rank = 45th , 2000DensityUS = 17.2 , 2000Density = 6.62 , MedianHouseholdIncome = $51,945 , IncomeRank = 45th , AdmittanceOrder = ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picuris Mountains
The Picuris Mountains are a mountain range in northern New Mexico. They are considered a subrange of the Sangre de Cristo Mountains. Geography The mountains are located to the east of Dixon and surround Picuris Pueblo to the west, north, and east. The range resembles a triangle with its base to the east, along the valley of the Rio Grande del Rancho. The northwest face lies along the valley of the Rio Grande and the southern face lies along Rio Pueblo and Embudo Creek. History The area was first visited by Europeans on July 13, 1598, when Juan de Oñate visited Picuris Pueblo. Geology The range is underlain by Precambrian rock beds of the Hondo Group and Vadito Group. It is the namesake for the Picuris orogeny. Economy Mining has been historically important in the Picuris Mountains. The Harding Pegmatite Mine was operated off and on from about 1900 to 1958, when it was donated to the University of New Mexico as an outdoor geological laboratory. At one time, the mine made ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fort Valley (Virginia)
Fort Valley is a mountain valley located primarily in Shenandoah County, Virginia. It is often called "valley within a valley" as it lies between the two arms of the northern part of the Blue Ridge mountain range in the Shenandoah Valley in the Ridge-and-Valley Appalachians geological zone. The eastern ridgeline of Fort Valley is named Massanutten Mountain and is basically continuous for the eastern length of Fort Valley, with a short stretch called Waterfall Mountain in the extreme south of the valley. The western ridgeline of the valley, also part of the greater Massanutten range, is composed primarily of three named mountains, from north to south: Three Top Mountain, Powell Mountain and Short Mountain. Additionally, behind Three Top and Powell mountains another ridgeline in the chain is called Green Mountain which is actually higher in elevation than the 3 westernmost named mountains and between which is a smaller highland valley, called Little Fort Valley. The far southern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Australia
South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories by area, and second smallest state by population. It has a total of 1.8 million people. Its population is the second most highly centralised in Australia, after Western Australia, with more than 77 percent of South Australians living in the capital Adelaide, or its environs. Other population centres in the state are relatively small; Mount Gambier, the second-largest centre, has a population of 33,233. South Australia shares borders with all of the other mainland states, as well as the Northern Territory; it is bordered to the west by Western Australia, to the north by the Northern Territory, to the north-east by Queensland, to the east by New South Wales, to the south-east by Victoria, and to the south by the Great Australian Bight.M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flinders Ranges
The Flinders Ranges are the largest mountain range in South Australia, which starts about north of Adelaide. The ranges stretch for over from Port Pirie to Lake Callabonna. The Adnyamathanha people are the Aboriginal group who have inhabited the range for tens of thousands of years. Its most well-known landmark is Wilpena Pound / Ikara, a formation that creates a natural amphitheatre covering and containing the range's highest peak, St Mary Peak (). The ranges include several national parks, the largest being the Ikara-Flinders Ranges National Park, as well as other protected areas. It is an area of great geological and palaeontological significance, and includes the oldest fossil evidence of animal life was discovered. The Ediacaran Period and Ediacaran biota take their name from the Ediacara Hills within the ranges. In August 2022, a nomination for the Flinders Ranges to be named a World Heritage Site was lodged. History The first humans to inhabit the Flinders ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilpena Pound
Wilpena Pound – also known by its Adnyamathanha language, Adnyamathanha name of Ikara, meaning "meeting place" – is a natural amphitheatre of mountains located north of Adelaide, South Australia, Australia in the heart of the Ikara-Flinders Ranges National Park. It is accessible via a sealed road which continues on to the northern Flinders Ranges, South Australia, Flinders Ranges town of Blinman, South Australia, Blinman and to the south, Hawker, South Australia, Hawker. Attempts at farming the Pound failed during the early 20th century. Following this, the tourism potential was recognised in 1945. Geomorphology The area is part of the Adelaide Geosyncline. Despite early amateur theories that it was some kind of ancient volcano, the actual Pound is a syncline, synclinal basin, with the fold axis running NNW-SSE through Edeowie Gorge at the northern end and Rawnsley's Bluff at the southern. A corresponding anticline is located in the adjacent Moralana Gorge, with the Elder ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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