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Syncline
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 Inters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilpena Pound
Wilpena Pound ("Ikara" in the Adnyamathanha language) is a major natural amphitheatre of mountains located north of Adelaide, South Australia, Australia in the heart of the Ikara-Flinders Ranges National Park. Its fringe is accessible by a sealed road between the towns of Hawker, South Australia, Hawker to the south and Blinman, South Australia, Blinman in the northern Flinders Ranges, South Australia, Flinders Ranges. It was used for grazing from the mid-nineteenth century to the mid-twentieth century and for cropping in the early twentieth century. Its tourism potential was recognised in 1949. Geomorphology The area is part of the Adelaide Geosyncline. Early amateur theories mistakenly suggested Wilpena Pound was an ancient volcano. The 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 Range ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticline
In structural geology, an anticline is a type of Fold (geology), fold that is an arch-like shape and has its oldest Bed (geology), beds at its core, whereas a syncline is the inverse of an anticline. A typical anticline is convex curve, convex up in which the hinge or crest is the location where the curvature is greatest, and the limbs are the sides of the fold that Strike and dip, dip away from the hinge. Anticlines can be recognized and differentiated from antiforms by a sequence of rock layers that become progressively older toward the center of the fold. Therefore, if age relationships between various Stratum, rock strata are unknown, the term antiform should be used. The progressing age of the rock strata towards the core and uplifted center, are the trademark indications for evidence of anticlines on a geological map. These formations occur because anticlinal ridges typically develop above thrust faults during crustal deformations. The uplifted core of the fold cau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sideling Hill
Sideling Hill, also Side Long Hill, is a long, steep, narrow mountain ridge in the Ridge-and-valley Appalachians, Ridge-and-Valley (or Allegheny Mountains) physiographic province of the Appalachian Mountains, located in Washington County, Maryland, Washington County in western Maryland and adjacent West Virginia and Pennsylvania, United States, USA. The highest point on the ridge is Fisher Point, at in Fulton County, Pennsylvania. Geology Sideling Hill is a syncline, syncline mountain, in a region of downward-folded (syncline, synclinal) stratum, rock strata between two upfolded anticlines. The ridge is capped by an erosion, erosion-resistant conglomerate (geology), conglomerate and sandstone of Mississippian age, Mississippian (early Carboniferous) geologic age, the Pocono Formation, Purslane Sandstone of the Pocono Formation. The ridge's slopes are formed of much more easily eroded kinds of rock, including the Devonian-Mississippian age, Mississippian Rockwell Formation, wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southland Syncline
The Southland Syncline is a major geological structure located in the Southland, New Zealand, Southland Region of New Zealand's South Island. The syncline folds the Mesozoic Greywacke, greywackes of the Stratigraphy of New Zealand, 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 stage (geology), stages and epoch (geology), epochs in the Permian, Triassic, and Jurassic periods in the New Ze ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saou
Saou () is a commune in the Drôme department in southeastern France. Population Syncline Saou is well known for its syncline. See also *Communes of the Drôme department A commune is an alternative term for an intentional community. Commune or comună or comune or other derivations may also refer to: Administrative-territorial entities * Commune (administrative division), a municipality or township ** List of comm ... References Communes of Drôme {{Drôme-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Basin
A structural basin is a large-scale structural geology, structural formation of rock stratum, strata formed by tectonics, tectonic warping (Fold (geology), folding) of previously flat-lying strata into a syncline fold. They are geological depression (geology), depressions, the inverse of dome (geology), domes. Elongated structural basins are a type of geological Trough (geology), trough. Some structural basins are sedimentary basins, aggregations of sediment that filled up a depression or accumulated in an area; others were formed by tectonic events long after the sedimentary layers were deposited. Basins may appear on a geologic map as roughly circular or elliptical, with concentric layers. Because the strata dip toward the center, the exposed strata in a basin are progressively younger from the outside in, with the youngest rocks in the center. Basins are often large in areal extent, often hundreds of kilometers across. Structural basins are often important sources of coal, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustal Deformation
Orogeny () is a mountain-building process that takes place at a convergent plate margin when plate motion compresses the margin. An or develops as the compressed plate crumples and is uplifted to form one or more mountain ranges. This involves a series of geological processes collectively called orogenesis. These include both structural deformation of existing continental crust and the creation of new continental crust through volcanism. Magma rising in the orogen carries less dense material upwards while leaving more dense material behind, resulting in compositional differentiation of Earth's lithosphere ( crust and uppermost mantle). A synorogenic (or synkinematic) process or event is one that occurs during an orogeny. The word ''orogeny'' comes . Although it was used before him, the American geologist G. K. Gilbert used the term in 1890 to mean the process of mountain-building, as distinguished from epeirogeny. Tectonics Orogeny takes place on the convergent margi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orogeny
Orogeny () is a mountain-mountain formation, building process that takes place at a convergent boundary, convergent plate margin when plate motion compresses the margin. An or develops as the compressed plate crumples and is tectonic uplift, uplifted to form one or more mountain ranges. This involves a series of geological processes collectively called orogenesis. These include both structural deformation (physics), deformation of existing continental crust and the creation of new continental crust through volcanism. Magma rising in the orogen carries less dense material upwards while leaving more dense material behind, resulting in compositional differentiation of Earth's lithosphere (crust (geology), crust and uppermost mantle (geology), mantle). A synorogenic (or synkinematic) process or event is one that occurs during an orogeny. The word ''orogeny'' comes . Although it was used before him, the American geologist Grove Karl Gilbert, G. K. Gilbert used the term in 1890 to me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hokonui Hills
The Hokonui Hills, also known as ''The Hokonui Mountains'' or simply ''The Hokonui'', are a range of hills in central Southland, New Zealand. They rise to 600 metres above the surrounding Southland Plains, of which the hills mark a northern extremity. The Hokonui forms part of the Southland Syncline, a geological fold system which extends northwestward from the coast at The Catlins. Owing to the transform fault which forms the Southern Alps, the westernmost part of the syncline has been transported several hundred kilometres to the north; this western section includes many of the hills within the Kahurangi National Park in the northwest of the South Island. The Hokonui Hills also splits the Southland Plains in two - to the north and east lies the broad floodplain of the Mataura River, and to the south and west lie the plains of the Aparima and Ōreti Rivers. The Ōreti's major tributary, the Makarewa River, rises in the south of the Hokonui Hills. The hills lie within a t ... [...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 Grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rockwell Formation
The Rockwell Formation is a late Devonian and early Mississippian mapped bedrock unit in West Virginia, Maryland, and Pennsylvania, in the United States. Description The Rockwell Formation was described at its type section at Rockwell Run in West Virginia as soft arkosic sandstone, fine hard conglomerate, and buff hackly shale. The formation was originally described in West Virginia by Stose and Swartz (1912). It was first described in Maryland by H. E. Vokes (1957),Vokes, H.E., 1957, Geography and geology of Maryland: Maryland Geological Survey Bulletin, no. 19, p. 243. and later described in central Pennsylvania by C. R. Wood (1980).Wood, C.R., 1980, Summary groundwater resources of Centre County, Pennsylvania: Pennsylvania Geological Survey Water Resource Report, 4th series, no. 48, p. 60. Stratigraphy The Rockwell is generally considered a Formation. At Formation rank, it has several members, including the Patton and Riddlesburg Shale Members,Kammer, T.W., and Bjersted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Geology
Structural geology is the study of the three-dimensional distribution of rock units with respect to their deformational histories. The primary goal of structural geology is to use measurements of present-day rock geometries to uncover information about the history of deformation ( strain) in the rocks, and ultimately, to understand the stress field that resulted in the observed strain and geometries. This understanding of the dynamics of the stress field can be linked to important events in the geologic past; a common goal is to understand the structural evolution of a particular area with respect to regionally widespread patterns of rock deformation (e.g., mountain building, rifting) due to plate tectonics. Use and importance The study of geologic structures has been of prime importance in economic geology, both petroleum geology and mining geology. Folded and faulted rock strata commonly form traps that accumulate and concentrate fluids such as petroleum and natural gas. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
