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Midcontinent Rift
The Midcontinent Rift System (MRS) or Keweenawan Rift is a long geological rift in the center of the North America, North American continent and south-central part of the North American plate. It formed when the continent's core, the North American craton, began to split apart during the Mesoproterozoic era of the Precambrian, about 1.1 billion years ago. aulacogen, The rift failed, leaving behind thick layers of igneous rock that are exposed in its northern reaches, but buried beneath later sedimentary formations along most of its western and eastern arms. Those arms meet at Lake Superior, which is contained within the rift valley. The lake's North Shore (Lake Superior), north shore in Ontario and Minnesota defines the northern arc of the rift. From the lake, the rift's eastern arm trends south to central lower Michigan, and possibly into Indiana, Ohio, Kentucky, Tennessee, and Alabama. The western arm runs from Lake Superior southwest through portions of Wisconsin, Minnesota, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kentucky
Kentucky (, ), officially the Commonwealth of Kentucky, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Illinois, Indiana, and Ohio to the north, West Virginia to the northeast, Virginia to the east, Tennessee to the south, and Missouri to the west. Its northern border is defined by the Ohio River. Its capital is Frankfort, Kentucky, Frankfort and its List of cities in Kentucky, most populous city is Louisville, Kentucky, Louisville. As of 2024, the state's population was approximately 4.6 million. Previously part of Colony of Virginia, colonial Virginia, Kentucky was admitted into the Union as the fifteenth state on June 1, 1792. It is known as the "Bluegrass State" in reference to Kentucky bluegrass, a species of grass introduced by European settlers which has long supported the state's thoroughbred horse industry. The fertile soil in the central and western parts of the state led to the development ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a Natural satellite, moon onto its surface. Lava may be erupted at a volcano or through a Fissure vent, fracture in the Crust (geology), crust, on land or underwater, usually at temperatures from . The volcanic rock resulting from subsequent cooling is often also called ''lava''. A lava flow is an outpouring of lava during an effusive eruption. (An explosive eruption, by contrast, produces a mixture of volcanic ash and other fragments called tephra, not lava flows.) The viscosity of most lava is about that of ketchup, roughly 10,000 to 100,000 times that of water. Even so, lava can flow great distances before cooling causes it to solidify, because lava exposed to air quickly develops a solid crust that insulates the remaining liquid lava, helping to keep it hot and inviscid enough to continue flowing. Etymology The word ''lava'' comes from Ital ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intrusive Rock
Intrusive rock is formed when magma penetrates existing rock, crystallizes, and solidifies underground to form ''Igneous intrusion, intrusions'', such as batholiths, dike (geology), dikes, Sill (geology), sills, laccoliths, and volcanic necks.Intrusive RocksIntrusive rocks accessdate: March 27, 2017.Igneous intrusive rocks, accessdate: March 27, 2017.Britannica.comintrusive rock , geology , Britannica.com accessdate: March 27, 2017. Intrusion is one of the two ways igneous rock can form. The other is extrusive rock, extrusion, such as a Types of volcanic eruptions, volcanic eruption or similar event. An intrusion is any body of intrusive igneous rock, formed from magma that cools and solidifies within the crust of the planet. In contrast, an ''extrusion'' consists of extrusive rock, formed above the surface of the crust. Some geologists use the term plutonic rock synonymously with intrusive rock, but other geologists subdivide intrusive rock, by crystal size, into coarse-grai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granite
Granite ( ) is a coarse-grained (phanerite, phaneritic) intrusive rock, intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions. These range in size from dike (geology), dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers. Granite is typical of a larger family of ''granitic rocks'', or ''granitoids'', that are composed mostly of coarse-grained quartz and feldspars in varying proportions. These rocks are classified by the relative percentages of quartz, alkali feldspar, and plagioclase (the QAPF diagram, QAPF classification), with true granite representing granitic rocks rich in quartz and alkali feldspar. Most granitic rocks also contain mica or amphibole minerals, though a few (known as leucogranites) conta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gabbro
Gabbro ( ) is a phaneritic (coarse-grained and magnesium- and iron-rich), mafic intrusive igneous rock formed from the slow cooling magma into a holocrystalline mass deep beneath the Earth's surface. Slow-cooling, coarse-grained gabbro is chemically equivalent to rapid-cooling, fine-grained basalt. Much of the Earth's oceanic crust is made of gabbro, formed at mid-ocean ridges. Gabbro is also found as plutons associated with continental volcanism. Due to its variant nature, the term ''gabbro'' may be applied loosely to a wide range of intrusive rocks, many of which are merely "gabbroic". By rough analogy, gabbro is to basalt as granite is to rhyolite. Etymology The term "gabbro" was used in the 1760s to name a set of rock types that were found in the ophiolites of the Apennine Mountains in Italy. It was named after Gabbro, a hamlet near Rosignano Marittimo in Tuscany. Then, in 1809, the German geologist Christian Leopold von Buch used the term more restrictively in his d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superior Upland
Superior may refer to: *Superior (hierarchy), something which is higher in a hierarchical structure of any kind Places * Superior (proposed U.S. state), an unsuccessful proposal for the Upper Peninsula of Michigan to form a separate state *Lake Superior, the largest of the North American Great Lakes, Canada, United States and the second largest lake in the world. United Kingdom * Rickinghall Superior, England United States *Superior, Arizona * Superior, Colorado * Superior, Indiana * Superior, Iowa * Superior Township, Chippewa County, Michigan * Superior Township, Washtenaw County, Michigan * Superior, Montana * Superior, Nebraska * Superior, West Virginia *Superior, Wisconsin, a city * Superior (town), Wisconsin, a town adjacent to the city * Superior (village), Wisconsin, a village adjacent to the city * Superior, Wyoming *Superior (RTA Rapid Transit station), a station on the RTA Red Line in Cleveland, Ohio * Superior Bay, a bay between Minnesota and Wisconsin * Superior ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oklahoma
Oklahoma ( ; Choctaw language, Choctaw: , ) is a landlocked U.S. state, state in the South Central United States, South Central region of the United States. It borders Texas to the south and west, Kansas to the north, Missouri to the northeast, Arkansas to the east, New Mexico to the west, and Colorado to the northwest. Partially in the western extreme of the Upland South, it is the List of U.S. states and territories by area, 20th-most extensive and the List of U.S. states and territories by population, 28th-most populous of the 50 United States. Its residents are known as Oklahomans and its capital and largest city is Oklahoma City. The state's name is derived from the Choctaw language, Choctaw words , 'people' and , which translates as 'red'. Oklahoma is also known informally by its List of U.S. state and territory nicknames, nickname, "The Sooner State", in reference to the Sooners, American pioneer, American settlers who staked their claims in formerly American Indian-o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kansas
Kansas ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the west. Kansas is named after the Kansas River, in turn named after the Kaw people, Kansa people. Its List of capitals in the United States, capital is Topeka, Kansas, Topeka, and its List of cities in Kansas, most populous city is Wichita, Kansas, Wichita; however, the largest urban area is the bi-state Kansas City metropolitan area split between Kansas and Missouri. For thousands of years, what is now Kansas was home to numerous and diverse Plains Indians, Indigenous tribes. The first settlement of non-indigenous people in Kansas occurred in 1827 at Fort Leavenworth. The pace of settlement accelerated in the 1850s, in the midst of political wars over the Slavery in the United States, slavery debate. When it was officially opened to settlement by the U.S. governm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nebraska
Nebraska ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Kansas to the south; Colorado to the southwest; and Wyoming to the west. Nebraska is the List of U.S. states and territories by area, 16th-largest state by land area, with just over . With a population of over 2 million as of 2024, it is the List of U.S. states and territories by population, 38th-most populous state and the List of states and territories of the United States by population density, eighth-least densely populated. Its List of capitals in the United States, capital is Lincoln, Nebraska, Lincoln, and its List of municipalities in Nebraska, most populous city is Omaha, Nebraska, Omaha, which is on the Missouri River. Nebraska was admitted into the United States in 1867, two years after the end of the American Civil War. The Nebras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iowa
Iowa ( ) is a U.S. state, state in the upper Midwestern United States, Midwestern region of the United States. It borders the Mississippi River to the east and the Missouri River and Big Sioux River to the west; Wisconsin to the northeast, Illinois to the east and southeast, Missouri to the south, Nebraska to the west, South Dakota to the northwest, and Minnesota to the north. Iowa is the List of U.S. states and territories by area, 26th largest in total area and the List of U.S. states and territories by population, 31st most populous of the List of states and territories of the United States, 50 U.S. states, with a population of 3.19 million. The state's List of capitals in the United States, capital, List of cities in Iowa, most populous city, and largest List of metropolitan statistical areas, metropolitan area fully located within the state is Des Moines, Iowa, Des Moines. A portion of the larger Omaha–Council Bluffs metropolitan area, Omaha, Nebraska, metropolitan area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
