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Geology Of Georgia (U.S. State)
The geology of Georgia consists of four distinct geologic regions, beginning in the northwest corner of the state and moving through the state to the southeast: the Valley and Ridge region and part of the Appalachian Plateau; the Blue Ridge; the Piedmont and the Coastal Plain. The Fall Line is the boundary between the Piedmont and the Coastal Plain. Appalachian Plateau and Valley and Ridge The Appalachian Plateau and the Valley and Ridge geologic region passes through the extreme northwest corner of Georgia. During the middle Ordovician Period (about 440 - 460 million years ago), the tectonic plate carrying this area collided with another plate, leading to the creation of a new subduction zone and the beginning of the Appalachians. As a result of this and later orogenies, alternating beds of hard and soft Paleozoic sedimentary rocks were folded, looking much like the wrinkles one would find in a kicked floor rug. In Georgia, the Valley and Ridge includes limestone, sandstone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Rocks
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by 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 geological detritus (minerals) or 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 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 the floor of water bodies (marine snow). Sedimentation may also occur as dissolved minerals precipitate from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georgia Gold Belt
The largest quantities of gold found in the eastern United States were found in the Georgia Gold Belt, extending from eastern Alabama to Rabun County, Georgia. The biggest concentration of gold was found in White, Lumpkin, and northern Cherokee counties in Georgia. The gold in the Georgia Gold Belt was close to 24 karat (100%) purity. Most of the gold was found in eroded rock ( saprolite) and mixed in with quartz. Besides placer deposits of gold, and gold bearing quartz in weathered rock, gold also occurs in quartz veins. The most profitable veins, in the Dahlonega District, occur in the contact zone between mica-schists and granite or diorite.Eckel, E.C. 1902, Gold and Pyrite Deposits of the Dahlonega District, Georgia, in Contributions to Economic Geology, USGS Bulletin No. 213, Washington: Government Printing Office The discovery of gold in the Georgia Gold Belt in 1828 led to the Georgia Gold Rush. The historic cities of Auraria and Dahlonega were the primary beneficiari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metavolcanic
Metavolcanic rock is volcanic rock that shows signs of having experienced metamorphism. In other words, the rock was originally produced by a volcano, either as lava or tephra. The rock was then subjected to high pressure, high temperature or both, for example by burial under younger rocks, causing the original volcanic rock to recrystallize. Metavolcanic rocks are sometimes described informally as ''metavolcanics''. When it is possible to determine the original volcanic rock type from the properties of the metavolcanic rock (particularly if the degree of metamorphism is slight), the rock is more precisely named by appylying the prefix ''meta-'' to the original rock type. For example, a weakly metamorphosed basalt would be described as a ''metabasalt'', or a weakly metamorphosed tuff as a ''metatuff''. Metavolcanic rock is commonly found in greenstone belt Greenstone belts are zones of variably metamorphosed mafic to ultramafic volcanic sequences with associated sedimentary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Igneous Rocks
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava. The magma can be derived from partial melts of existing rocks in either a planet's mantle or crust. Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, or without crystallization to form natural glasses. Igneous rocks occur in a wide range of geological settings: shields, platforms, orogens, basins, large igneous provinces, extended crust and oceanic crust. Geological significance Igneous and metamorphic rocks make up 90–95% of the top ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphic Rocks
Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causing profound physical or chemical changes. During this process, the rock remains mostly in the solid state, but gradually recrystallizes to a new texture or mineral composition. The protolith may be an igneous, sedimentary, or existing metamorphic rock. Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface. They are classified by their protolith, their chemical and mineral makeup, and their texture. They may be formed simply by being deeply buried beneath the Earth's surface, where they are subject to high temperatures and the great pressure of the rock layers above. They can also form from tectonic processes such as continental collisions, which cause horizontal pressure, friction, and distort ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brasstown Bald
Brasstown Bald is the highest point in the U.S. state of Georgia. It is located in the northeastern part of the state in the Blue Ridge Mountains on the border between Towns and Union counties south of the city of Hiawassee. The mountain is known to the native Cherokee people as Enotah. Description The name in English is derived from a mistaken translation of the term for the nearby Cherokee village of Brasstown, located along the upper Brasstown Creek (named in English from the same error) feeding the Hiawassee River. Across the North Carolina state line, immediately north of the mountain, are other places named in that error of English settlers: Brasstown, a community in the Brasstown township of Clay County, North Carolina. Brasstown Bald is partly in both Towns and Union counties, the peak being divided by the county line. The mountain is part of the Blue Ridge Mountains (part of the Appalachian Mountains), and within the borders of the Blue Ridge Ranger District of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Georgia Mountains
The Georgia Mountains Region or North Georgia mountains or Northeast Georgia is an area that starts in the northeast corner of Georgia (U.S. state), Georgia, United States, and spreads in a westerly direction. The mountains in this region are in the Blue Ridge Mountains, Blue Ridge mountain chain that ends in Georgia. At over 1 billion years of age, the Blue Ridge mountains are among the oldest mountains in the United States and sometimes mistaken to be the oldest mountains in the world (they are only about one third of the age of South Africa's 3.6 billion year old Kaapvaal craton#Barberton greenstone belt, Barberton greenstone belt.). The mountains in this region are also a part of the vast system of North American mountains known as the Appalachian Mountains that spans most of the United States longitudally along the eastern areas of the nation and terminates in Alabama. The region is known for its ruggedness and scenic beauty. The Cherokee who lived in these mountains calle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carters Dam
Carters Dam is an earthen embankment dam located south of Chatsworth in Murray County and west of Ellijay in northwestern Georgia, United States, that creates Carters Lake. Description The dam is tall and is situated above the mouth of the Coosawattee River. The drainage area is . The dam took 15 years to build and was completed in . The area of the primary flood control pool is . The top elevation of the dam is . The top width of the dam is . The dam is constructed of rock and earth and is the tallest earthen dam east of the Mississippi River. The dam has a diversion tunnel that is . It is a horseshoe shape with a bottom width of The lake is the deepest manmade reservoir east of the Mississippi River and deepest lake in Georgia. The created lake is more than deep and has of shoreline without any private docks or other development. Hydroelectric plant Below the dam is a retention and re-regulation lake (Reregulation Reservoir). The hydroelectric plant is of the pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous ( Pennsylvanian) and Permian times. Many significant coal deposits are younger than this and originate from the Mesozoic and Cenozoic eras. Coal is used primarily as a fuel. While coal has been known and used for thousands of years, its usage was limited until the Industrial Revolution. With the invention of the steam engine, coal consumption increased. In 2020, coal supplied about a quarter of the world's primary energy and over a third of its electricity. Some iron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ochre
Ochre ( ; , ), or ocher in American English, is a natural clay earth pigment, a mixture of ferric oxide and varying amounts of clay and sand. It ranges in colour from yellow to deep orange or brown. It is also the name of the colours produced by this pigment, especially a light brownish-yellow. A variant of ochre containing a large amount of hematite, or dehydrated iron oxide, has a reddish tint known as "red ochre" (or, in some dialects, ruddle). The word ochre also describes clays coloured with iron oxide derived during the extraction of tin and copper. Earth pigments Ochre is a family of earth pigments, which includes yellow ochre, red ochre, purple ochre, sienna, and umber. The major ingredient of all the ochres is iron(III) oxide-hydroxide, known as limonite, which gives them a yellow colour. * Yellow ochre, , is a hydrated iron hydroxide (limonite) also called gold ochre. * Red ochre, , takes its reddish colour from the mineral hematite, which is an anhydrous iron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barite
Baryte, barite or barytes ( or ) is a mineral consisting of barium sulfate ( Ba S O4). Baryte is generally white or colorless, and is the main source of the element barium. The ''baryte group'' consists of baryte, celestine (strontium sulfate), anglesite (lead sulfate), and anhydrite (calcium sulfate). Baryte and celestine form a solid solution (Ba,Sr)SO4. Names and history The radiating form, sometimes referred to as ''Bologna Stone'', attained some notoriety among alchemists for specimens found in the 17th century near Bologna by Vincenzo Casciarolo. These became phosphorescent upon being calcined. Carl Scheele determined that baryte contained a new element in 1774, but could not isolate barium, only barium oxide. Johan Gottlieb Gahn also isolated barium oxide two years later in similar studies. Barium was first isolated by electrolysis of molten barium salts in 1808 by Sir Humphry Davy in England. The American Petroleum Institute specification API 13/ISO 13500, which gover ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
