Related Research Articles
Orogeny is a mountain building process that takes place at a convergent plate margin when plate motion compresses the margin. An orogenic belt or orogen 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. A synorogenic process or event is one that occurs during an orogeny.
The geology of the Appalachians dates back more than 480 million years. The rocks exposed in today's Appalachian Mountains reveal elongate belts of folded and thrust faulted marine sedimentary rocks, volcanic rocks and slivers of ancient ocean floor – strong evidence that these rocks were deformed during plate collision. The birth of the Appalachian ranges marks the first of several mountain building plate collisions that culminated in the construction of the supercontinent Pangaea with the Appalachians and neighboring Anti-Atlas mountains near the center. These mountain ranges likely once reached elevations similar to those of the Alps and the Rocky Mountains before they were eroded.
The Acadian orogeny is a long-lasting mountain building event which began in the Middle Devonian, reaching a climax in the early Late Devonian. It was active for approximately 50 million years, beginning roughly around 375 million years ago, with deformational, plutonic, and metamorphic events extending into the Early Mississippian. The Acadian orogeny is the third of the four orogenies that created the Appalachian orogen and subsequent basin. The preceding orogenies consisted of the Potomac and Taconic orogeny, which followed a rift/drift stage in the Late Neoproterozoic. The Acadian orogeny involved the collision of a series of Avalonian continental fragments with the Laurasian continent. Geographically, the Acadian orogeny extended from the Canadian Maritime provinces migrating in a southwesterly direction toward Alabama. However, the Northern Appalachian region, from New England northeastward into Gaspé region of Canada, was the most greatly affected region by the collision.
The Molasse basin is a foreland basin north of the Alps which formed during the Oligocene and Miocene epochs. The basin formed as a result of the flexure of the European plate under the weight of the orogenic wedge of the Alps that was forming to the south.
A foreland basin is a structural basin that develops adjacent and parallel to a mountain belt. Foreland basins form because the immense mass created by crustal thickening associated with the evolution of a mountain belt causes the lithosphere to bend, by a process known as lithospheric flexure. The width and depth of the foreland basin is determined by the flexural rigidity of the underlying lithosphere, and the characteristics of the mountain belt. The foreland basin receives sediment that is eroded off the adjacent mountain belt, filling with thick sedimentary successions that thin away from the mountain belt. Foreland basins represent an endmember basin type, the other being rift basins. Space for sediments is provided by loading and downflexure to form foreland basins, in contrast to rift basins, where accommodation space is generated by lithospheric extension.
The Alice Springs Orogeny was a major intraplate tectonic episode in central Australia responsible for the formation of a series of large mountain ranges. The deformation associated with the Alice Spring Orogeny caused the vertically-tilted sandstone layers of the iconic Uluru/Ayers Rock.
The geology of China consists of three Precambrian cratons surrounded by a number of orogenic belts. The modern tectonic environment is dominated by the continued collision of India with the rest of Asia starting 40–50 million years ago. This has formed the Himalayas and continues to deform most of China. China has vast mineral reserves, a significant earthquake risk in its western regions and rare isolated active volcanoes throughout the country.
The Lachlan Fold Belt (LFB) or Lachlan Orogen is a geological subdivision of the east part of Australia. It is a zone of folded and faulted rocks of similar age. It dominates New South Wales and Victoria, also extending into Tasmania, the Australian Capital Territory and Queensland. It was formed in the Middle Paleozoic from 450 to 340 Mya. It was earlier known as Lachlan Geosyncline. It covers an area of 200,000 km2.
The Wyoming Craton is a craton in the west-central United States and western Canada – more specifically, in Montana, Wyoming, southern Alberta, southern Saskatchewan, and parts of northern Utah. Also called the Wyoming Province, it is the initial core of the continental crust of North America.
West Virginia's geologic history stretches back into the Precambrian, and includes several periods of mountain building and erosion. At times, much of what is now West Virginia was covered by swamps, marshlands, and shallow seas, accounting for the wide variety of sedimentary rocks found in the state, as well as its wealth of coal and natural gas deposits. West Virginia has had no active volcanism for hundreds of millions of years, and does not experience large earthquakes, although smaller tremors are associated with the Rome Trough, which passes through the western part of the state.
The Rhenohercynian Zone or Rheno-Hercynian zone in structural geology describes a fold belt of west and central Europe, formed during the Hercynian orogeny. The zone consists of folded and thrust Devonian and early Carboniferous sedimentary rocks that were deposited in a back-arc basin along the southern margin of the then existing paleocontinent Laurussia.
The Pyrenees are a 430-kilometre-long, roughly east–west striking, intracontinental mountain chain that divide France, Spain, and Andorra. The belt has an extended, polycyclic geological evolution dating back to the Precambrian. The chain's present configuration is due to the collision between the microcontinent Iberia and the southwestern promontory of the European Plate. The two continents were approaching each other since the onset of the Upper Cretaceous (Albian/Cenomanian) about 100 million years ago and were consequently colliding during the Paleogene (Eocene/Oligocene) 55 to 25 million years ago. After its uplift, the chain experienced intense erosion and isostatic readjustments. A cross-section through the chain shows an asymmetric flower-like structure with steeper dips on the French side. The Pyrenees are not solely the result of compressional forces, but also show an important sinistral shearing.
The geology of Russia, the world's largest country, which extends over much of northern Eurasia, consists of several stable cratons and sedimentary platforms bounded by orogenic (mountain) belts.
The Scandinavian Mountains or the Scandes is a mountain range that runs through the Scandinavian Peninsula. The western sides of the mountains drop precipitously into the North Sea and Norwegian Sea, forming the fjords of Norway, whereas to the northeast they gradually curve towards Finland. To the north they form the border between Norway and Sweden, reaching 2,000 metres (6,600 ft) high at the Arctic Circle. The mountain range just touches northwesternmost Finland but are scarcely more than hills at their northernmost extension at the North Cape.
The geology of North America is a subject of regional geology and covers the North American continent, the third-largest in the world. Geologic units and processes are investigated on a large scale to reach a synthesized picture of the geological development of the continent.
The Scandinavian Caledonides are the vestiges of an ancient, today deeply eroded orogenic belt formed during the Silurian–Devonian continental collision of Baltica and Laurentia, which is referred to as the Scandian phase of the Caledonian orogeny. The size of the Scandinavian Caledonides at the time of their formation can be compared with the size of the Himalayas. The area east of the Scandinavian Caledonides, including parts of Finland, developed into a foreland basin where old rocks and surfaces were covered by sediments. Today, the Scandinavian Caledonides underlay most of the western and northern Scandinavian Peninsula, whereas other parts of the Caledonides can be traced into West and Central Europe as well as parts of Greenland and eastern North America.
The geology of Sweden is the regional study of rocks, minerals, tectonics, natural resources and groundwater in the country. The oldest rocks in Sweden date to more than 2.5 billion years ago in the Precambrian. Complex orogeny mountain building events and other tectonic occurrences built up extensive metamorphic crystalline basement rock that often contains valuable metal deposits throughout much of the country. Metamorphism continued into the Paleozoic after the Snowball Earth glaciation as the continent Baltica collided with an island arc and then the continent Laurentia. Sedimentary rocks are most common in southern Sweden with thick sequences from the last 250 million years underlying Malmö and older marine sedimentary rocks forming the surface of Gotland.
The geology of the State of New York is made up of ancient Precambrian crystalline basement rock, forming the Adirondack Mountains and the bedrock of much of the state. These rocks experienced numerous deformations during mountain building events and much of the region was flooded by shallow seas depositing thick sequences of sedimentary rock during the Paleozoic. Fewer rocks have deposited since the Mesozoic as several kilometers of rock have eroded into the continental shelf and Atlantic coastal plain, although volcanic and sedimentary rocks in the Newark Basin are a prominent fossil-bearing feature near New York City from the Mesozoic rifting of the supercontinent Pangea.
The Parnaíba Basin is a large cratonic sedimentary basin located in the North and Northeast portion of Brazil. About 50% of its areal distribution occurs in the state of Maranhão, and the other 50% occurring in the state of Pará, Piauí, Tocantins, and Ceará. It is one of the largest Paleozoic basins in the South American Platform. The basin has a roughly ellipsoidal shape, occupies over 600,000 km2, and is composed of ~3.4 km of mainly Paleozoic sedimentary rock that overlies localized rifts.
References
- ↑ Døssing, A.; Japsen Anthony B. Watts Tove Nielsen Wilfried Jokat Hans Thybo Trine Dahl‐Jensen, P.; Watts, A.B.; Nielsen, T.; Kojat, W.; Thybo, H.; Dahl-Jensen, T. (2016). "Miocene uplift of the NE Greenland margin linked to plate tectonics: Seismic evidence from the Greenland Fracture Zone, NE Atlantic". Tectonics. doi: 10.1002/2015TC004079 .
- Britannica Encyclopedia article of East Greenland orogen
- Abstract of the paper "Foreland-propagating Caledonian thrust systems in East Greenland"
 | This Greenland location article is a stub. You can help Wikipedia by expanding it. |
 | This article about a regional geological feature is a stub. You can help Wikipedia by expanding it. |