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Central Iapetus Magmatic Province
The Central Iapetus magmatic province (CIMP) was a large igneous province (LIP) that occurred during the Ediacaran (615–550 ) between several ancient continents – Laurentia and Baltica and, possibly, Amazonia – during the break-up of the supercontinent Rodinia and resulted in the opening of the Iapetus Ocean. With a potential radius of up to , the CIMP was one of the larger volcanic events on Earth, similar in size to the 200 Ma Central Atlantic Magmatic Province. Evidences for the CIMP have also been found in Mexico, Morocco, and Svalbard. The CIMP coincides with the Marinoan and Gaskiers glaciations and precedes the so-called Cambrian explosion, the evolution of modern lineages. The CIMP left extensive traces along the Appalachians in eastern North America to which the Baltoscandian margin a conjugate. No traces of the CIMP have been found in Amazonia, however, and it is possible Laurentia and Amazonia separated during 1000 Ma-rifting eve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Large Igneous Province
A large igneous province (LIP) is an extremely large accumulation of igneous rocks, including intrusive (sills, dikes) and extrusive (lava flows, tephra deposits), arising when magma travels through the crust towards the surface. The formation of LIPs is variously attributed to mantle plumes or to processes associated with divergent plate tectonics. The formation of some of the LIPs in the past 500 million years coincide in time with mass extinctions and rapid climatic changes, which has led to numerous hypotheses about causal relationships. LIPs are fundamentally different from any other currently active volcanoes or volcanic systems. Definition In 1992 researchers first used the term ''large igneous province'' to describe very large accumulations—areas greater than 100,000 square kilometers (approximately the area of Iceland)—of mafic igneous rocks that were erupted or emplaced at depth within an extremely short geological time interval: a few million years or less. Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandinavian Caledonides
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. Plate-tectonic history The Caledonian Wilson cycle commenced with the continental break-up of Rodinia and the opening of the Iapetus ocean about 616–583 Ma ( mega-annum) ago. The Iapetus was at its widest in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manitou Islands (Lake Nipissing)
The Manitou Islands are a series of small islands in Lake Nipissing, in Nipissing District, Ontario, Canada. The islands form a circle and lie southwest of North Bay. History Samuel de Champlain visited the islands in 1613 and called them "pretty". Fur traders found the island a handy resting spot, and often would camp overnight. Today the islands' sand beaches continue to be a popular resting and recreation spot for many boaters. Lime was quarried on the islands in the 1880s when the Canadian Pacific Railway was built, and a lime kiln was operated to create lime for mortar. Great Manitou Island, the largest of the islands, once held a dance hall and hotel, but it burned to the ground. Uranium mining was conducted on Newman Island in the 1950s. Local legend says that the island is haunted by the Nipissing people who died of starvation after battling the Iroquois and being forced to flee the islands. In 1972 the wreck of the steamship '' John B. Fraser'' was found between Goose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Labrador Sea-Baffin Bay Rift
The Canadian Arctic Rift System is a major North American geological structure extending from the Labrador Sea in the southeast through Davis Strait, Baffin Bay and the Arctic Archipelago in the northwest. It consists of a series of interconnected rifts that formed during the Paleozoic, Mesozoic and Cenozoic eras. Extensional tectonics, Extensional stresses along the entire length of the rift system have resulted in a variety of tectonic features, including grabens, half-grabens, structural basin, basins and fault (geology), faults. Development of the Canadian Arctic Rift System was accompanied by two plate tectonic episodes that originated on opposite sides of the North American Plate and were propagated toward each other. Both were strongly controlled by pre-existing structures, which either guided the propagating faults or impeded their growth. The rift system is now inactive apart from minor adjustments that are indicated by occasional earthquakes in Baffin Bay and the Labrado ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catoctin Mountain
Catoctin Mountain, along with the geologically associated Bull Run Mountains, forms the easternmost mountain ridge of the Blue Ridge Mountains, which are in turn a part of the Appalachian Mountains range. The ridge runs northeast–southwest for about departing from South Mountain near Emmitsburg, Maryland, and running south past Leesburg, Virginia, where it disappears into the Piedmont in a series of low-lying hills near New Baltimore, Virginia. The ridge forms the eastern rampart of the Loudoun and Middletown valleys. Geography Catoctin Mountain traverses Frederick County, Maryland, and extends into northern Loudoun County, Virginia. It rises to its greatest elevation of above sea level just southwest of Cunningham Falls State Park and is transected by gaps at Braddock Heights (Fairview Pass), Point of Rocks on the Potomac River and Clarke's Gap west of Leesburg, as well as several other unnamed passes in Maryland and Virginia. The mountain is much lower in elevation in V ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sept-ÃŽles, Quebec
Sept-Îles ( Quebec French pronunciation : , French for "Seven Islands") is a city in the Côte-Nord region of eastern Quebec. It is among the northernmost locales with a paved connection to the rest of Quebec's road network. The population was 25,686 as of the 2011 Canadian census. The town is called Uashat, meaning "bay" in Innu-aimun. The city is well known for having major iron companies like Iron Ore Company of Canada and the Cleveland-Cliffs mining company. The city relies heavily on the iron industry. Sept-Îles has among the highest average wages and the highest average wage increases. The only settlements on the paved road network that are farther north are Fermont, Radisson and Chisasibi, the latter two of which are in the extreme western part of the province at the north end of the James Bay Road. The only other settlements at higher latitudes in the province are mostly isolated Cree, Innu, or Inuit villages, with access limited to seasonal gravel roads. Sep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saint Lawrence Rift System
The Saint Lawrence rift system is a seismically active zone paralleling the Saint Lawrence River. The rift system trends northeast and southwest and forms a half-graben that links the Ottawa-Bonnechere and the Saguenay grabens. The rift system extends more than along the Saint Lawrence valley from the Ottawa – Montreal area. Within the system, fault reactivation is believed to occur along late Proterozoic to early Paleozoic normal faults related to the opening of the Iapetus Ocean. Two significant historically active seismic zones occur along this system associated with northwest trending intersecting graben structures. The Charlevoix region has been the location of at least five magnitude six or larger earthquakes over the last 350 years, including the 1925 Charlevoix–Kamouraska earthquake. At the Lower St Lawrence zone the largest recorded earthquakes are about magnitude five. Seismic studies indicate a crustal convergence across the Saint Lawrence valley of about per ye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alnö Complex
The Alnö Complex or Alnö Alkaline Complex is a group of carbonatite and alkaline igneous rocks in Alnö in the eastern coast of central Sweden that intruded the basement in Late Ediacaran times. The Alnö Complex is made up by a series of concentric dykes within a radius of 25 km of a main "central complex" of intrusions. In addition the Alnö Complex proper is surrounded by a 500 to 600 m broad zone of metasomatic rock that was formed by metasomatic alteration of the existing Precambrian migmatite gneiss basement. The specific type of metasomatic rock is referred by some authors as "fenite". The dykes of the complex consist of carbonatite and alkaline rocks such melilite and sövite. It has been proposed that both the Fen Complex in Southern Norway and the Alnö Complex formed as consequence to mild extensional tectonics in the ancient continent of Baltica following the opening of the Iapetus Ocean. Harry von Eckermann published a landmark study on the Alnà ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fen Complex
The Fen Complex ( no, Fensfeltet) in Nome, Telemark, Norway is a region noted for an unusual suite of igneous rocks. Several varieties of carbonatite are present in the area as well as lamprophyre, ijolite and other highly alkalic rocks. It is the type locality for fenite, a metasomatic rock commonly found around carbonatite and alkali intrusives.http://www.mindat.org/loc-14357.html Mindat location description The Fen Complex is a roughly circular area about three kilometres in diameter. It is located just west of the Oslo graben. Radiometric age dating on the carbonatites gave an age of 539 +/- 14 Myr. The host rocks for the intrusions are middle Proterozoic granites and gneiss and the complex was associated with the Cambrian rifting of the cratonic rocks.Faure, Gunter (2000) ''Origin of Igneous Rocks'', Springer, pp. 319-321 The complex is a protected location because of the rare minerals and rock types found there. The rocks were first described by Waldemar Christofer Brøgg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lac Pommeroy Dykes
Lac is the resinous secretion of a number of species of lac insects, of which the most commonly cultivated is ''Kerria lacca''. Cultivation begins when a farmer gets a stick that contains eggs ready to hatch and ties it to the tree to be infested. Thousands of lac insects colonize the branches of the host trees and secrete the resinous pigment. The coated branches of the host trees are cut and harvested as sticklac. The harvested sticklac is crushed and sieved to remove impurities. The sieved material is then repeatedly washed to remove insect parts and other material. The resulting product is known as seedlac. The prefix ''seed'' refers to its pellet shape. Seedlac, which still contains 3–5% impurity, is processed into shellac by heat treatment or solvent extraction. The leading producer of lac is Jharkhand, followed by the Chhattisgarh, West Bengal, and Maharashtra states of India. Lac production is also found in Bangladesh, Myanmar, Thailand, Laos, Vietnam, parts of C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grenville Dike Swarm
The Grenville dike swarm is a large Proterozoic dike swarm in the Canadian provinces of Ontario and Quebec. It is one of the several major magmatic events in the Canadian Shield and it possibly formed 590 million years ago along a triple junction that might have been related to a mantle plume. The maximum length of the Grenville dike swarm is . The Ottawa-Bonnechere Graben is associated with the Grenville dike swarm, as some of its features date from that time. See also *Volcanism of Canada *Volcanism of Eastern Canada *Grenville orogeny The Grenville orogeny was a long-lived Mesoproterozoic mountain-building event associated with the assembly of the supercontinent Rodinia. Its record is a prominent orogenic belt which spans a significant portion of the North American continent, f ... References Dike swarms Igneous petrology of Ontario Igneous petrology of Quebec Proterozoic magmatism {{Canada-geology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long Range Dikes
The Long Range dikes are a Neoproterozoic mafic dike swarm of Newfoundland and Labrador, Canada. It consists of a large igneous province with an area of that was constructed about 620 million years ago when Laurentia broke-up from Baltica. Its formation might have occurred when the ancient Iapetus Ocean began to open. Long Range is the oldest of a series of magmatic events that occurred along the eastern margin of Laurentia 620–560 Ma, before the opening of the Iapetus Ocean. It can be linked to magmatism in Baltica, the basaltic dike swarm in Egersund, Norway, and Baltoscandian swarms. It was followed by the 590 Ma Grenville-Adirondack swarm, Upstate New York, associated with separation from Amazonia The Amazon rainforest, Amazon jungle or ; es, Selva amazónica, , or usually ; french: Forêt amazonienne; nl, Amazoneregenwoud. In English, the names are sometimes capitalized further, as Amazon Rainforest, Amazon Forest, or Amazon Jungle. ... and the 56 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
