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Quartzites
Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of hematite. Other colors, such as yellow, green, blue and orange, are due to other minerals. The term ''quartzite'' is also sometimes used for very hard but unmetamorphosed sandstones that are composed of quartz grains thoroughly cemented with additional quartz. Such sedimentary rock has come to be described as orthoquartzite to distinguish it from metamorphic quartzite, which is sometimes called metaquartzite to emphasize its metamorphic origins. Quartzite is very resistant to chemical weathering and often forms ridges and resistant hilltops. The nearly pure silica conte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartzite Mine In Kakwa Park
Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of hematite. Other colors, such as yellow, green, blue and orange, are due to other minerals. The term ''quartzite'' is also sometimes used for very hard but unmetamorphosed sandstones that are composed of quartz grains thoroughly cemented with additional quartz. Such sedimentary rock has come to be described as orthoquartzite to distinguish it from metamorphic quartzite, which is sometimes called metaquartzite to emphasize its metamorphic origins. Quartzite is very resistant to chemical weathering and often forms ridges and resistant hilltops. The nearly pure silica conte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartzite Sollières
Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of hematite. Other colors, such as yellow, green, blue and orange, are due to other minerals. The term ''quartzite'' is also sometimes used for very hard but unmetamorphosed sandstones that are composed of quartz grains thoroughly cemented with additional quartz. Such sedimentary rock has come to be described as orthoquartzite to distinguish it from metamorphic quartzite, which is sometimes called metaquartzite to emphasize its metamorphic origins. Quartzite is very resistant to chemical weathering and often forms ridges and resistant hilltops. The nearly pure silica conte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diagenesis
Diagenesis () is the process that describes physical and chemical changes in sediments first caused by water-rock interactions, microbial activity, and compaction after their deposition. Increased pressure and temperature only start to play a role as sediments become buried much deeper in the Earth's crust. In the early stages, the transformation of poorly consolidated sediments into sedimentary rock (lithification) is simply accompanied by a reduction in porosity and water expulsion (clay sediments), while their main mineralogical assemblages remain unaltered. As the rock is carried deeper by further deposition above, its organic content is progressively transformed into kerogens and bitumens. The process of diagenesis excludes surface alteration (weathering) and deep metamorphism. There is no sharp boundary between diagenesis and metamorphism, but the latter occurs at higher temperatures and pressures. Hydrothermal solutions, meteoric groundwater, rock porosity, permeability, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baraboo Range
The Baraboo Range is a syncline located in Columbia and Sauk Counties, Wisconsin. It consists of highly eroded Precambrian metamorphic rock. It is about long and varies from 5 to in width. The Wisconsin River, previously traveling in a north to south direction, turns to the east just north of the range before making its turn to the west towards the Upper Mississippi River. The eastern end of the range was glaciated during the Wisconsinian glaciation, while the western half was not, and consequently, marks the eastern boundary of Wisconsin's Driftless Area. The city of Baraboo is in the center of the valley. The range was designated a National Natural Landmark in 1980. Geology The range is an example of a buried mountain range exposed through erosion, to once again undergo the forces of surface erosion. The rocks are as much as 1.5 billion years old,Hanson, G. F.''Geology of the Baraboo District, Wisconsin'', The University of Wisconsin Extension, November 1970, Information C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devil's Lake State Park (Wisconsin)
Devil's Lake State Park is a state park located in the Baraboo Range in eastern Sauk County, just south of Baraboo, Wisconsin. It is around thirty-five miles northwest of Madison, and is on the western edge of the last ice-sheet deposited during the Wisconsin glaciation. The state park encompasses , making it the largest in Wisconsin. The state park is known for its quartzite bluffs along the Devil's Lake, which was created by a glacier depositing terminal moraines that plugged the north and south ends of the gap in the bluffs during the last ice age approximately 12,000 years ago. The sand at the bottom of Devil's Lake is thought to be deposited by glaciers. There are many quartzite rock formations, such as Balanced Rock and Devil's Doorway, throughout the park. Effigy mounds are also located throughout the park. The park contains approximately eleven miles of the Ice Age Trail. Its scenic beauty, along with its proximity to the Wisconsin Dells, has made it one of the most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minnesota
Minnesota () is a state in the upper midwestern region of the United States. It is the 12th largest U.S. state in area and the 22nd most populous, with over 5.75 million residents. Minnesota is home to western prairies, now given over to intensive agriculture; deciduous forests in the southeast, now partially cleared, farmed, and settled; and the less populated North Woods, used for mining, forestry, and recreation. Roughly a third of the state is covered in forests, and it is known as the "Land of 10,000 Lakes" for having over 14,000 bodies of fresh water of at least ten acres. More than 60% of Minnesotans live in the Minneapolis–Saint Paul metropolitan area, known as the "Twin Cities", the state's main political, economic, and cultural hub. With a population of about 3.7 million, the Twin Cities is the 16th largest metropolitan area in the U.S. Other minor metropolitan and micropolitan statistical areas in the state include Duluth, Mankato, Moorhead, Rochester, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Dakota
South Dakota (; Sioux language, Sioux: , ) is a U.S. state in the West North Central states, North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Lakota people, Lakota and Dakota people, Dakota Sioux Native Americans in the United States, Native American tribes, who comprise a large portion of the population with nine Indian reservation, reservations currently in the state and have historically dominated the territory. South Dakota is the List of U.S. states and territories by area, seventeenth largest by area, but the List of U.S. states and territories by population, 5th least populous, and the List of U.S. states and territories by population density, 5th least densely populated of the List of U.S. states, 50 United States. As the southern part of the former Dakota Territory, South Dakota became a state on November 2, 1889, simultaneously with North Dakota. They are the 39th and 40th states admitted to the union; Pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porphyroblasts
A porphyroblast is a large mineral crystal in a metamorphic rock which has grown within the finer grained matrix. Porphyroblasts are commonly euhedral crystals, but can also be partly to completely irregular in shape. The most common porphyroblasts in metapelites (metamorphosed mudstones and siltstones) are garnets and staurolites, which stand out in well- foliated metapelites (such as schists) against the platy mica matrix. A similar type of crystal is a ''phenocryst'', a large crystal in an igneous rock. Porphyroblasts are often confused with ''porphyroclasts'', which can also be large outstanding crystals, but which are ''older'' than the matrix of the rock. If a porphyroblastic mineral has small inclusions of minerals within it, the mineral is described as poikiloblastic. This observation can help interpret deformation history. A rock which has many porphyroblasts is described as having a ''porphyroblastic texture''. As porphyroblasts grow, the foliation may be pres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field Work
Field research, field studies, or fieldwork is the collection of raw data outside a laboratory, library, or workplace setting. The approaches and methods used in field research vary across disciplines. For example, biologists who conduct field research may simply observe animals interacting with their environments, whereas social scientists conducting field research may interview or observe people in their natural environments to learn their languages, folklore, and social structures. Field research involves a range of well-defined, although variable, methods: informal interviews, direct observation, participation in the life of the group, collective discussions, analyses of personal documents produced within the group, self-analysis, results from activities undertaken off- or on-line, and life-histories. Although the method generally is characterized as qualitative research, it may (and often does) include quantitative dimensions. History Field research has a long histor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary
Sedimentary rocks are types of rock (geology), rock that are formed by the accumulation or deposition of mineral or organic matter, organic particles at Earth#Surface, Earth's surface, followed by cementation (geology), cementation. Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment, and may be composed of detritus (geology), geological detritus (minerals) or detritus, biological detritus (organic matter). The geological detritus originated from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or Mass wasting, mass movement, which are called agents of denudation. Biological detritus was formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetite
Magnetite is a mineral and one of the main iron ores, with the chemical formula Fe2+Fe3+2O4. It is one of the oxides of iron, and is ferrimagnetic; it is attracted to a magnet and can be magnetized to become a permanent magnet itself. With the exception of extremely rare native iron deposits, it is the most magnetic of all the naturally occurring minerals on Earth. Naturally magnetized pieces of magnetite, called lodestone, will attract small pieces of iron, which is how ancient peoples first discovered the property of magnetism. Magnetite is black or brownish-black with a metallic luster, has a Mohs hardness of 5–6 and leaves a black streak. Small grains of magnetite are very common in igneous and metamorphic rocks. The chemical IUPAC name is iron(II,III) oxide and the common chemical name is ''ferrous-ferric oxide''. Properties In addition to igneous rocks, magnetite also occurs in sedimentary rocks, including banded iron formations and in lake and marine sediments ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
