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39-715: The Kalkankale Formation, consisting of old sandstone , mudstone and claystone dating back to early Pliocene period, underlies wide areas at Lake Kuyucuk and the surrounding landscape, and forms the flat and low-sloped terrain of the region. Elevations north of the lake are formed by agglomerate , tuff and andesite of early Pliocene old Kura volcanic rocks while the southwestern elevations are formed by tuff, andesite, pearlite , pumice and obsidian of Dumanlıdağ pyroclastic rocks . Büyükalamet Heights 1,676 m (5,499 ft), Küçükalamet Heights 1,657 m (5,436 ft), Kızılgüney Heights 1,646 m (5,400 ft) and Uzungüney Heights 1,660 m (5,450 ft) in

78-480: A thin section using a method like the Gazzi-Dickinson Method . This yields the relative percentages of quartz, feldspar, and lithic grains and the amount of clay matrix. The composition of a sandstone can provide important information on the genesis of the sediments when used with a triangular Q uartz, F eldspar, L ithic fragment ( QFL diagrams ). However, geologist have not been able to agree on

117-452: A Turkish non-governmental organization for ecological research and community-based nature conservation, has operated a station at the lake to carry out birdwatching , bird ringing and bird counting. Lake Kuyucuk hosted Kars' first bird ringing station, where over 22,500 birds of 170 species were ringed until January 2010. Bird ringing starts in April. In 2011, a birdwatching tower was built at

156-478: A sandstone goes through as the degree of kinetic processing of the sediments increases. Dott's (1964) sandstone classification scheme is one of many such schemes used by geologists for classifying sandstones. Dott's scheme is a modification of Gilbert's classification of silicate sandstones, and it incorporates R.L. Folk's dual textural and compositional maturity concepts into one classification system. The philosophy behind combining Gilbert's and R. L. Folk's schemes

195-462: A set of boundaries separating regions of the QFL triangle. Visual aids are diagrams that allow geologists to interpret different characteristics of a sandstone. For example, a QFL chart can be marked with a provenance model that shows the likely tectonic origin of sandstones with various compositions of framework grains. Likewise, the stage of textural maturity chart illustrates the different stages that

234-445: A twofold classification: Cement is what binds the siliciclastic framework grains together. Cement is a secondary mineral that forms after deposition and during burial of the sandstone. These cementing materials may be either silicate minerals or non-silicate minerals, such as calcite. Sandstone that becomes depleted of its cement binder through weathering gradually becomes friable and unstable. This process can be somewhat reversed by

273-438: Is Kuyucuk village, 1 km (0.62 mi) west of the lake. Until 1920, the village was inhabited by Molokans , members of a Christian sect. Later, Karapapaks , a Turkic-speaking sub-ethnic group of Azerbaijanis , settled in the village. A village school building, built by Molokans in 1907, is still intact. From the 1909-built three-story Russian orthodox church, only the first floor has survived. Other buildings, preserved from

312-837: Is a distinction that can be recognized in the field . In turn, the distinction between an orthoquartzite and a metaquartzite is the onset of recrystallization of existing grains. The dividing line may be placed at the point where strained quartz grains begin to be replaced by new, unstrained, small quartz grains, producing a mortar texture that can be identified in thin sections under a polarizing microscope. With increasing grade of metamorphism, further recrystallization produces foam texture , characterized by polygonal grains meeting at triple junctions, and then porphyroblastic texture , characterized by coarse, irregular grains, including some larger grains ( porphyroblasts .) Sandstone has been used since prehistoric times for construction, decorative art works and tools. It has been widely employed around

351-520: Is a wetland site for at least 233 bird species, and is a Ramsar site designated as of international importance in 2009, stretching over an area of 416 ha (4.16 km). It is Turkey's thirteenth Ramsar site, and the first one in eastern Turkey. The lake has great ornithological importance, being on the African-Eurasian flyway of migratory birds . It has been recognized by BirdLife International as an Important Bird Area in 2004. In

390-411: Is at minimum. By January 2014, it was reported by KuzeyDoğa that the wildlife at the lake is endangered due to dropping water levels. The lake's water level decreased down to 2–3 m (6.6–9.8 ft). That resulted in connecting of the artificial breeding islet with the lake shore at some places, which brings the birds in danger by predators. Moreover, the vegetation on the islet was destroyed as it

429-523: Is likely formed during eogenesis. Deeper burial is accompanied by mesogenesis , during which most of the compaction and lithification takes place. Compaction takes place as the sand comes under increasing pressure from overlying sediments. Sediment grains move into more compact arrangements, ductile grains (such as mica grains) are deformed, and pore space is reduced. In addition to this physical compaction, chemical compaction may take place via pressure solution . Points of contact between grains are under

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468-431: Is redeposited in the unstrained pore spaces. Mechanical compaction takes place primarily at depths less than 1,000 meters (3,300 ft). Chemical compaction continues to depths of 2,000 meters (6,600 ft), and most cementation takes place at depths of 2,000–5,000 meters (6,600–16,400 ft). Unroofing of buried sandstone is accompanied by telogenesis , the third and final stage of diagenesis. As erosion reduces

507-443: Is that it is better able to "portray the continuous nature of textural variation from mudstone to arenite and from stable to unstable grain composition". Dott's classification scheme is based on the mineralogy of framework grains, and on the type of matrix present in between the framework grains. In this specific classification scheme, Dott has set the boundary between arenite and wackes at 15% matrix. In addition, Dott also breaks up

546-413: Is used to get to the lake. Sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks . Most sandstone is composed of quartz or feldspar , because they are the most resistant minerals to the weathering processes at

585-646: The American Southwest . Rock formations composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs . Quartz-bearing sandstone can be changed into quartzite through metamorphism , usually related to tectonic compression within orogenic belts . Sandstones are clastic in origin (as opposed to either organic , like chalk and coal , or chemical , like gypsum and jasper ). The silicate sand grains from which they form are

624-549: The Global Heritage Stone Resource . In some regions of Argentina, the orthoquartzite-stoned facade is one of the main features of the Mar del Plata style bungalows. Southern vole Microtus rossiaemeridionalis Ognev , 1924 Microtus epiroticus Ondrias, 1966 Microtus levis Miller, 1908 The East European vole ( Microtus mystacinus ) is a species of vole ( rodent ) in

663-425: The duckweed family ( Lemna ), common reed ( Phragmites australis ) and rushes ( Juncus ) while the steppe flora are shrubs and herbs ( Astragalus , Onobrychis ), vetches ( Vicia ), daisy ( Artemisia ), common dandelion ( Taraxacum officinale ) and alsike clover ( Trifolium hybridum ). The globally threatened plant species grass ( Elymus sosnowskyi ), which is endemic to Turkey, grows here. Lake Kuyucuk

702-509: The reptile species sand lizard ( Lacerta agilis ). The highly acidic water of the lake does not support fish species. The Lake Kuyucuk and its surroundings are situated in the coldest zone of Eastern Anatolia characterized with harsh continental climate . Winters are long and very cold, summers are moderate, even coolish. Maximum precipitation is observed in May while in January precipitation

741-497: The Earth's surface. Like uncemented sand , sandstone may be imparted any color by impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Because sandstone beds can form highly visible cliffs and other topographic features, certain colors of sandstone have become strongly identified with certain regions, such as the red rock deserts of Arches National Park and other areas of

780-455: The Molokan times, are the village chambers. Nature tourists and birdwatchers come to Lake Kuyucuk between the beginning of spring and the end of fall. The site is also visited by students of local schools and colleges on special days like World Biodiversity Day , World Environment Day , International Migratory Bird Day and Birdwatching Day. The ruined medieval Armenian city-site Ani and

819-491: The application of tetraethyl orthosilicate (Si(OC 2 H 5 ) 4 ) which will deposit amorphous silicon dioxide between the sand grains. The reaction is as follows. Pore space includes the open spaces within a rock or a soil. The pore space in a rock has a direct relationship to the porosity and permeability of the rock. The porosity and permeability are directly influenced by the way the sand grains are packed together. Sandstones are typically classified by point-counting

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858-562: The basin and to immediately reform the islet by digging a ditch around. The European Destinations of Excellence (EDEN) of the European Commission has listed Lake Kuyucuk as a notable tourist wildlife reserve since 2009. In 2012, a tourism center was built in Kuyucuk Village near the lake to serve for ecotourism . Since 2011, an annual two-day birdwatching festival is held in mid June. The nearest populated place

897-473: The common minerals most resistant to weathering processes at the Earth's surface, as seen in the Goldich dissolution series . Framework grains can be classified into several different categories based on their mineral composition: Matrix is very fine material, which is present within interstitial pore space between the framework grains. The nature of the matrix within the interstitial pore space results in

936-456: The depositional environment, older sand is buried by younger sediments, and it undergoes diagenesis . This mostly consists of compaction and lithification of the sand. Early stages of diagenesis, described as eogenesis , take place at shallow depths (a few tens of meters) and are characterized by bioturbation and mineralogical changes in the sands, with only slight compaction. The red hematite that gives red bed sandstones their color

975-407: The depth of burial, renewed exposure to meteoric water produces additional changes to the sandstone, such as dissolution of some of the cement to produce secondary porosity . Framework grains are sand-sized (0.0625-to-2-millimeter (0.00246 to 0.07874 in) diameter) detrital fragments that make up the bulk of a sandstone. Most framework grains are composed of quartz or feldspar , which are

1014-446: The different types of framework grains that can be present in a sandstone into three major categories: quartz, feldspar, and lithic grains. When sandstone is subjected to the great heat and pressure associated with regional metamorphism , the individual quartz grains recrystallize, along with the former cementing material, to form the metamorphic rock called quartzite . Most or all of the original texture and sedimentary structures of

1053-750: The fall, up to 45,000 birds stop over at the lake. An artificial islet on the lake was formed in 2009 to provide a safe breeding place for bird species and to help protect them from predators. The Ramsar site harbors bird species such as ruddy shelduck ( Tadorna ferruginea ), the globally endangered white-headed duck ( Oxyura leucocephala ), vulnerable red-breasted goose ( Branta ruficollis ), vulnerable velvet scoter ( Melanitta fusca ), western marsh harrier ( Circus aeruginosus ), common crane ( Grus grus ), black-winged stilt ( Himantopus himantopus ), Eurasian coot ( Fulica atra ), black-necked grebe ( Podiceps nigricollis ), common starling ( Sturnus vulgaris ) and greylag goose ( Anser anser ). KuzeyDoğa ,

1092-580: The family Cricetidae . It is found in Albania , Bulgaria , Finland , Greece , Iran , Svalbard (accidentally introduced from 1920), North Macedonia , Romania , Russia , Serbia and Montenegro , Slovakia , Turkey , Ukraine and Norway . On Svalbard, they were first discovered in 1960 in the Grumantbyen area, and were thought to be the common vole until a genetic analysis correctly identified them in 1990. This Microtus article

1131-433: The greatest strain, and the strained mineral is more soluble than the rest of the grain. As a result, the contact points are dissolved away, allowing the grains to come into closer contact. Lithification follows closely on compaction, as increased temperatures at depth hasten deposition of cement that binds the grains together. Pressure solution contributes to cementing, as the mineral dissolved from strained contact points

1170-442: The hardness of individual grains, uniformity of grain size and friability of their structure, some types of sandstone are excellent materials from which to make grindstones , for sharpening blades and other implements. Non-friable sandstone can be used to make grindstones for grinding grain, e.g., gritstone . A type of pure quartz sandstone, orthoquartzite, with more of 90–95 percent of quartz, has been proposed for nomination to

1209-485: The lake. In September 2004, over 20,000 ruddy shelduck, which makes out almost 12% of the world population, were observed on the lake in just one day. Other notable fauna found around the lake are the mammal species red fox ( Vulpes vulpes ), Nehring's blind mole rat ( Spalax nehringi ), southern vole ( Microtus levis ) and marbled polecat ( Vormela peregusna ), the amphibians European green toad ( Bufo viridis ) and marsh frog ( Pelophylax ridibundus ) as well as

Lake Kuyucuk - Misplaced Pages Continue

1248-493: The much lower temperatures and pressures associated with diagenesis of sedimentary rock, but diagenesis has cemented the rock so thoroughly that microscopic examination is necessary to distinguish it from metamorphic quartzite. The term orthoquartzite is used to distinguish such sedimentary rock from metaquartzite produced by metamorphism. By extension, the term orthoquartzite has occasionally been more generally applied to any quartz-cemented quartz arenite . Orthoquartzite (in

1287-464: The narrow sense) is often 99% SiO 2 with only very minor amounts of iron oxide and trace resistant minerals such as zircon , rutile and magnetite . Although few fossils are normally present, the original texture and sedimentary structures are preserved. The typical distinction between a true orthoquartzite and an ordinary quartz sandstone is that an orthoquartzite is so highly cemented that it will fracture across grains, not around them. This

1326-463: The north, Alaca Heights 1,693 m (5,554 ft) in the west and Cadalı Heights 1,772 m (5,814 ft), Yumru Heights 1,656 m (5,433 ft) and Mevzili Heights 1,655 m (5,430 ft) in the southwest are the elevations around the lake making up the landscape's topography. At an elevation of 1,627 m (5,338 ft), the lake region has two ecosystems, steppe and wetland . The wetland flora are free-floating aquatic plants from

1365-638: The product of physical and chemical weathering of bedrock. Weathering and erosion are most rapid in areas of high relief, such as volcanic arcs , areas of continental rifting , and orogenic belts . Eroded sand is transported by rivers or by the wind from its source areas to depositional environments where tectonics has created accommodation space for sediments to accumulate. Forearc basins tend to accumulate sand rich in lithic grains and plagioclase . Intracontinental basins and grabens along continental margins are also common environments for deposition of sand. As sediments continue to accumulate in

1404-530: The ruins of an 11th-century Shaddadids mosque, the Manucehr mosque (Menucehr camii) within the site of Ani, are notable tourist attractions in the vicinity. Lake Çıldır is another tourist destination in the region. Lake Kuyucuk is accessible through the state road D.060 , which crosses over the northern part of the lake. It is about 40 km (25 mi) northeast of Kars and 15 km (9.3 mi) west of Akyaka, Kars . The road through Kuyucuk village

1443-417: The sandstone are erased by the metamorphism. The grains are so tightly interlocked that when the rock is broken, it fractures through the grains to form an irregular or conchoidal fracture. Geologists had recognized by 1941 that some rocks show the macroscopic characteristics of quartzite, even though they have not undergone metamorphism at high pressure and temperature. These rocks have been subject only to

1482-626: The world in constructing temples, churches, homes and other buildings, and in civil engineering . Although its resistance to weathering varies, sandstone is easy to work. That makes it a common building and paving material, including in asphalt concrete . However, some types that have been used in the past, such as the Collyhurst sandstone used in North West England , have had poor long-term weather resistance, necessitating repair and replacement in older buildings. Because of

1521-424: Was used by the local herdsmen as fodder for their livestock. The negative change of the ecosystem was caused mostly by water levels dropping due to insufficient water inflow and excessive extraction of groundwater from local wells drilled by the villagers. In addition, the creek feeding the lake is used as watering trough for livestock by blocking their flow. KuzeyDoğa proposed to set up a planning for water supply in

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