Dolomite (rock) in the context of "Karst topography"

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⭐ Core Definition: Dolomite (rock)

Dolomite (also known as dolomite rock, dolostone or dolomitic rock) is a sedimentary carbonate rock that contains a high percentage of the mineral dolomite, CaMg(CO3)2. It occurs widely, often in association with limestone and evaporites, though it is less abundant than limestone and rare in Cenozoic rock beds (beds less than about 66 million years in age). One of the first geologists to distinguish dolomite from limestone was Déodat Gratet de Dolomieu, a French mineralogist and geologist after whom it is named. He recognized and described the distinct characteristics of dolomite in the late 18th century, differentiating it from limestone.

Most dolomite was formed as a magnesium replacement of limestone or of lime mud before lithification. The geological process of conversion of calcite to dolomite is known as dolomitization and any intermediate product is known as dolomitic limestone. The "dolomite problem" refers to the vast worldwide depositions of dolomite in the past geologic record in contrast to the limited amounts of dolomite formed in modern times. Sulfate-reducing bacteria living in anoxic conditions can precipitate dolomite suggesting that some past dolomite deposits might be due to microbial activity. Recent laboratory research focused on the crystal growth of dolomite at the microscopic scale has revealed that multiple cycles of precipitation/dissolution can promote the growth of dolomite crystals.

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Dolomite (rock) in the context of Limestone

Limestone is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate CaCO3. Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life.

About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, CaMg(CO3)2. Magnesian limestone is an obsolete and poorly defined term used variously for dolomite, for limestone containing significant dolomite (dolomitic limestone), or for any other limestone containing a significant percentage of magnesium. Most limestone was formed in shallow marine environments, such as continental shelves or platforms, though smaller amounts were formed in many other environments. Much dolomite is secondary dolomite, formed by chemical alteration of limestone. Limestone is exposed over large regions of the Earth's surface, and because limestone is slightly soluble in rainwater, these exposures often are eroded to become karst landscapes. Most cave systems are found in limestone bedrock.

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Dolomite (rock) in the context of Karst

Karst (/kɑːrst/) is a topography formed from the dissolution of soluble carbonate rocks such as limestone and dolomite. It is characterized by features like poljes above and drainage systems with sinkholes and caves underground. There is some evidence that karst may occur in more weathering-resistant rocks such as quartzite given the right conditions.

Subterranean drainage may limit surface water, with few if any rivers or lakes. In regions where the dissolved bedrock is covered (perhaps by debris) or confined by one or more superimposed non-soluble rock strata, distinctive karst features may occur only at subsurface levels and can be totally missing above ground.

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Dolomite (rock) in the context of Cliff

In geography and geology, a cliff or rock face is an area of rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers. Cliffs are usually composed of rock that is resistant to weathering and erosion. The sedimentary rocks that are most likely to form cliffs include sandstone, limestone, chalk, and dolomite. Igneous rocks such as granite and basalt also often form cliffs.

An escarpment (or scarp) is a type of cliff formed by the movement of a geologic fault, a landslide, or sometimes by rock slides or falling rocks which change the differential erosion of the rock layers.

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Dolomite (rock) in the context of Hvar

Hvar (pronounced [xvâːr]; Chakavian: Hvor or For; Greek: Φάρος, romanizedPharos; Latin: Pharia; Italian: Lesina) is a Croatian island in the Adriatic Sea, located off the Dalmatian coast, lying between the islands of Brač, Vis and Korčula. Approximately 68 kilometres (42.25 mi) long, with a high east–west ridge of Mesozoic limestone and dolomite, the island of Hvar is unusual in the area for having a large fertile coastal plain, and fresh water springs. Its hillsides are covered in pine forests, with vineyards, olive groves, fruit orchards and lavender fields in the agricultural areas. The climate is characterized by mild winters, and warm summers with many hours of sunshine. The island has 10,678 residents according to the 2021 census, making it the fourth most populated of the Croatian islands.

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Dolomite (rock) in the context of Carbonate rock

Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. The two major types are limestone, which is composed of calcite or aragonite (different crystal forms of CaCO3), and dolomite rock (also known as dolostone), which is composed of dolomite (CaMg(CO3)2). They are usually classified on the basis of texture and grain size. Importantly, carbonate rocks can exist as metamorphic and igneous rocks, too. When recrystallized carbonate rocks are metamorphosed, marble is created. Rare igneous carbonate rocks even exist as intrusive carbonatites and, even rarer, there exists volcanic carbonate lava.

Carbonate rocks are also crucial components to understanding geologic history due to processes such as diagenesis in which carbonates undergo compositional changes based on kinetic effects. The correlation between this compositional change and temperature can be exploited to reconstruct past climate as is done in paleoclimatology. Carbonate rocks can also be used for understanding various other systems as described below.

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Dolomite (rock) in the context of Dolomite (mineral)

Dolomite (/ˈdɒl.əˌmt, ˈd.lə-/) is an anhydrous carbonate mineral composed of calcium magnesium carbonate, ideally CaMg(CO3)2. The term is also used for a sedimentary carbonate rock composed mostly of the mineral dolomite (see Dolomite (rock)). An alternative name sometimes used for the dolomitic rock type is dolostone.

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Dolomite (rock) in the context of Llogara National Park

Llogara National Park (Albanian: Parku Kombëtar i Llogarasë/Llogorasë) is a national park centered on the Ceraunian Mountains along the Albanian Riviera in southwestern Albania, spanning a surface area of 1,769 ha (17.69 km). The park's terrain includes large alpine meadows, vertical rock faces, precipices and dense forests. Most area of the park is covered by forests and was established in 1966 to protect several ecosystems and biodiversity of national importance. The International Union for Conservation of Nature (IUCN) has listed the park as Category II. The region has been recognised as an important Bird and Plant Area, supporting significant number of species.

The park features outstanding diversity with the landscape ranging from the alpine peaks of the Ceraunian Mountains covered with snow in winter to the sunny Albanian Ionian Sea Coast in summer. At 1,027 m (3,369 ft), the Llogara Pass provides a striking scenery, with tall mountains overlooking the Albanian Riviera and several islands in the sea. The region experiences a mediterranean climate. This means that the summers are hot and the winters generally dry to warm to cool. Despite the vicinity to the mediterranean climatic region, an alpine climate prevails at the Maja e Çikës. Geomorphologically, carbonate rocks occupy most of the area, while the mountains are composed of limestones and dolomites.

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Dolomite (rock) in the context of Karst lake

Karst lakes are formed as the result of a collapse of caves, especially in water-soluble rocks such as limestone, gypsum and dolomite. This process is known as karstification. They can cover areas of several hundred square kilometres. Their shallow lakebed is usually an insoluble layer of sediment so that water is impounded, leading to the formation of lakes. Many karst lakes only exist periodically, but return regularly after heavy rainfall.

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