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The Belcher Mountains are a former mountain range that stood in the Hudson Bay region of Canada in the late Precambrian. The mountains have since been uplifted and folded erosion has beveled them into a nearly flat plain.
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The Belcher Mountains are a former mountain range that stood in the Hudson Bay region of Canada in the late Precambrian. The mountains have since been uplifted and folded erosion has beveled them into a nearly flat plain.
Exposed plunging folded sedimentary and volcanic strata in Canada's Hudson Bay region outline the former position of the Belcher Mountains that stood in the late Precambrian. The folds trend northward. In the millions of years since, the mountains were uplifted and folded erosion has beveled them into a nearly flat plain. The lines running across the units are fractures and faults caused by the deformation of the units.
The Canadian Shield, also called the Laurentian Shield or the Laurentian Plateau, is a geologic shield, a large area of exposed Precambrian igneous and high-grade metamorphic rocks. It forms the North American Craton, the ancient geologic core of the North American continent. Glaciation has left the area with only a thin layer of soil, through which exposures of igneous bedrock resulting from its long volcanic history are frequently visible. As a deep, common, joined bedrock region in eastern and central Canada, the shield stretches north from the Great Lakes to the Arctic Ocean, covering over half of Canada and most of Greenland; it also extends south into the northern reaches of the continental United States.
The Belcher Islands are an archipelago in the southeast part of Hudson Bay near the centre of the Nastapoka arc. The Belcher Islands are spread out over almost 3,000 km2 (1,200 sq mi). Administratively, they belong to the Qikiqtaaluk Region of Nunavut, Canada. The hamlet of Sanikiluaq is on the north coast of Flaherty Island and is the southernmost in Nunavut. Along with Flaherty Island, the other large islands are Kugong Island, Tukarak Island, and Innetalling Island. Other main islands in the 1,500–island archipelago are Moore Island, Wiegand Island, Split Island, Snape Island and Mavor Island, while island groups include the Sleeper Islands, King George Islands, and Bakers Dozen Islands.
The geology of the Appalachians dates back more than 1.2 billion years to the Mesoproterozoic era when two continental cratons collided to form the supercontinent Rodinia, 500 million years prior to the development of the range during the formation of Pangea. 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 evidences 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 Pangea 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.
In the context of physical geography, the Intermontane Plateaus is one of eight physiographic regions of the contiguous United States. The region consists mostly of plateaus and mountain ranges lying between the Rocky Mountains on the east and the Cascade and Sierra Nevada Mountains on the west. It is subdivided into three physiographic provinces: the Columbia Plateau in the north, the Basin and Range Province in the central and southwestern portions, and the Colorado Plateau in the southeast. In turn, each of these provinces are each subdivided into a number of physiographic sections.
The Llano Uplift is a geologically ancient, low geologic dome that is about 90 miles (140 km) in diameter and located mostly in Llano, Mason, San Saba, Gillespie, and Blanco counties, Texas. It consists of an island-like exposure of Precambrian igneous and metamorphic rocks surrounded by outcrops of Paleozoic and Cretaceous sedimentary strata. At their widest, the exposed Precambrian rocks extend about 65 miles (105 km) westward from the valley of the Colorado River and beneath a broad, gentle topographic basin drained by the Llano River. The subdued topographic basin is underlain by Precambrian rocks and bordered by a discontinuous rim of flat-topped hills. These hills are the dissected edge of the Edwards Plateau, which consist of overlying Cretaceous sedimentary strata. Within this basin and along its margin are down-faulted blocks and erosional remnants of Paleozoic strata which form prominent hills.
The Baltic Shield is a segment of the Earth's crust belonging to the East European Craton, representing a large part of Fennoscandia, northwestern Russia and the northern Baltic Sea. It is composed mostly of Archean and Proterozoic gneisses and greenstone which have undergone numerous deformations through tectonic activity. It contains the oldest rocks of the European continent with a thickness of 250–300 km.
The Interior Plains is a vast physiographic region that spreads across the Laurentian craton of central North America, extending along the east flank of the Rocky Mountains from the Gulf Coast region to the Arctic Beaufort Sea. In Canada, it encompasses the Canadian Prairies separating the Canadian Rockies from the Canadian Shield, as well as the Boreal Plains and Taiga Plains east of the Mackenzie and Richardson Mountains; while in the United States, it includes the Great Plains of the West/Midwest and the tallgrass prairie region to the south of the Great Lakes extending east to the Appalachian Plateau region.
In geology and physical geography, a plateau, also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised steeply above the surrounding area on both the side. Often one or more sides have deep hills or escarpments. Plateaus can be formed by a number of processes, including upwelling of volcanic magma, extrusion of lava, and erosion by water and glaciers. Plateaus are classified according to their surrounding environment as intermontane, piedmont, or continental. A few plateaus may have a small flat top while others have wider ones.
The richly textured landscape of the United States is a product of the dueling forces of plate tectonics, weathering and erosion. Over the 4.5 billion-year history of the Earth, tectonic upheavals and colliding plates have raised great mountain ranges while the forces of erosion and weathering worked to tear them down. Even after many millions of years, records of Earth's great upheavals remain imprinted as textural variations and surface patterns that define distinctive landscapes or provinces.
The geology of the Grand Teton area consists of some of the oldest rocks and one of the youngest mountain ranges in North America. The Teton Range, partly located in Grand Teton National Park, started to grow some 9 million years ago. An older feature, Jackson Hole, is a basin that sits aside the range.
The exposed geology of the Capitol Reef area presents a record of mostly Mesozoic-aged sedimentation in an area of North America in and around Capitol Reef National Park, on the Colorado Plateau in southeastern Utah.
New Jersey is a very geologically and geographically diverse region in the United States' Middle Atlantic region, offering variety from the Appalachian Mountains and the Highlands in the state's northwest, to the Atlantic Coastal Plain region that encompasses both the Pine Barrens and the Jersey Shore. The state's geological features have impacted the course of settlement, development, commerce and industry over the past four centuries.
The Trans-Hudson orogeny or Trans-Hudsonian orogeny was the major mountain building event (orogeny) that formed the Precambrian Canadian Shield and the North American Craton, forging the initial North American continent. It gave rise to the Trans-Hudson orogen (THO), or Trans-Hudson Orogen Transect (THOT), which is the largest Paleoproterozoic orogenic belt in the world. It consists of a network of belts that were formed by Proterozoic crustal accretion and the collision of pre-existing Archean continents. The event occurred 2.0–1.8 billion years ago.
Cape Town lies at the south-western corner of the continent of Africa. It is bounded to the south and west by the Atlantic Ocean, and to the north and east by various other municipalities in the Western Cape province of South Africa.
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 geology of South Africa is highly varied including cratons, greenstone belts, large impact craters as well as orogenic belts. The geology of the country is the base for a large mining sector that extracts gold, diamonds, iron and coal from world-class deposits. The geomorphology of South Africa consists of a high plateau rimmed to west, south and southeast by the Great Escarpment, and the rugged mountains of the Cape Fold Belt. Beyond this there is strip of narrow coastal plain.
The geology of Wyoming includes some of the oldest Archean rocks in North America, overlain by thick marine and terrestrial sediments formed during the Paleozoic, Mesozoic and Cenozoic, including oil, gas and coal deposits. Throughout its geologic history, Wyoming has been uplifted several times during the formation of the Rocky Mountains, which produced complicated faulting that traps hydrocarbons.
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 geology of Montana includes thick sequences of Paleozoic, Mesozoic and Cenozoic sedimentary rocks overlying ancient Archean and Proterozoic crystalline basement rock. Eastern Montana has considerable oil and gas resources, while the uplifted Rocky Mountains in the west, which resulted from the Laramide orogeny and other tectonic events have locations with metal ore.
The geology of Denmark includes 12 kilometers of unmetamorphosed sediments lying atop the Precambrian Fennoscandian Shield, the Norwegian-Scottish Caledonides and buried North German-Polish Caledonides. The stable Fennoscandian Shield formed from 1.45 billion years ago to 850 million years ago in the Proterozoic. The Fennoscandian Border Zone is a large fault, bounding the deep basement rock of the Danish Basin—a trough between the Border Zone and the Ringkobing-Fyn High. The Sorgenfrei-Tornquist Zone is a fault-bounded area displaying Cretaceous-Cenozoic inversion.
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