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Peninsular Gneiss

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Gneiss ( / n aɪ s / nice ) is a common and widely distributed type of metamorphic rock . It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks . This rock is formed under pressures anywhere from 2 to 15 kbar, sometimes even more, and temperatures over 300 °C (572 °F). Gneiss nearly always shows a banded texture characterized by alternating darker and lighter colored bands and without a distinct cleavage .

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53-562: Peninsular Gneiss or Peninsular Gniessic Complex are the gneissic complex of the metamorphics found all over the Indian Peninsula , on top of which, the supra-crustal Dharwar System have been laid down. The term was first fashioned by W.F.Smeeth of the Mysore Geological Department in 1916 based on the first scientific study of this rock exposure. One of the best exposures of this rock mass, dated 2.5 to 3.4 billion years,

106-418: A border rich in biotite mica . Later magmatic activity represented by grey poryphiritic granite followed by pink massive granite is also seen at several places. The gneisses and granites have been profusely invaded by still younger veins of coarse grained pegmatite which have cut up the gneisses into several irregular and lenticular shapes. . The earliest rock was a dark coloured amphibolite which

159-572: A broad textural category for medium- to coarse-grained metamorphic rock that shows poorly developed schistosity, with compositional layering over 5 millimeters (0.20 in) thick and tending to split into plates over 1 centimeter (0.39 in) thick. Neither definition depends on composition or origin, though rocks poor in platy minerals are more likely to produce gneissose texture. Gneissose rocks thus are largely recrystallized but do not carry large quantities of micas, chlorite or other platy minerals. Metamorphic rock showing stronger schistosity

212-468: A popular choice among millennials in the city. In 2003 and 2006 Dharwad hosted the International men's tennis tournament ATP Challenger Series . Hubli-Dharwad Municipal Corporation (HDMC) was constituted in 1962 by combining two cities separated by a distance of 20 kilometers. The area covered by the corporation is 213 km (82 sq mi), spread over 45 revenue villages. The population of

265-579: A small habitation. For centuries, Dharwad acted as a resting place for travelers and a gateway between the Malenadu (western mountains) and the Bayalu Seeme (plains). The Chalukyas ruled Dharwad during the 12th century. A stone inscription indicates that there was a ruler by the name of BhaskaraDeva in 1117. In the 14th century, the district was first overrun by the Bahmani Sultanate , after which it

318-573: Is a city located in the northwestern part of the Indian state of Karnataka. It is the headquarters of the Dharwad district of Karnataka and forms a contiguous urban area with the city of Hubballi. It was merged with Hubballi in 1962 to form the twin cities of Hubballi-Dharwad . It covers an area of 213 km (82 sq mi) and is located 430 km (270 mi) northwest of Bangalore , on NH-48 , between Bangalore and Pune . In 2016, Hubli-Dharwad

371-475: Is a gneiss resulting from metamorphism of granite, which contains characteristic elliptic or lenticular shear-bound grains ( porphyroclasts ), normally feldspar , surrounded by finer grained material. The finer grained material deforms around the more resistant feldspar grains to produce this texture. Migmatite is a gneiss consisting of two or more distinct rock types, one of which has the appearance of an ordinary gneiss (the mesosome ), and another of which has

424-479: Is a metamorphic rock composed of mineral grains easily seen with the unaided eye, which form obvious compositional layers, but which has only a weak tendency to fracture along these layers. In Europe, the term has been more widely applied to any coarse, mica -poor, high-grade metamorphic rock. The British Geological Survey (BGS) and the International Union of Geological Sciences (IUGS) both use gneiss as

477-518: Is called gneissic banding. The darker bands have relatively more mafic minerals (those containing more magnesium and iron ). The lighter bands contain relatively more felsic minerals (minerals such as feldspar or quartz , which contain more of the lighter elements, such as aluminium , sodium , and potassium ). The banding is developed at high temperature when the rock is more strongly compressed in one direction than in other directions ( nonhydrostatic stress ). The bands develop perpendicular to

530-449: Is classified as schist, while metamorphic rock devoid of schistosity is called a granofels . Gneisses that are metamorphosed igneous rocks or their equivalent are termed granite gneisses, diorite gneisses, and so forth. Gneiss rocks may also be named after a characteristic component such as garnet gneiss, biotite gneiss, albite gneiss, and so forth. Orthogneiss designates a gneiss derived from an igneous rock , and paragneiss

583-736: Is located at Lal Bagh in Bangalore . The exposure is also called the Lalbagh rock. The Archean gneisses and schists , which are the oldest rocks of the Indian Shield , constitute a considerable area of Peninsular India. The Dharwar (Super Group) and the Peninsular Gneissic Complex are the classified groups of the Precambrian rocks of India. The extent of the Archean system is depicted as

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636-501: Is now part of the downtown area. The topographic setting of the Lalbagh rock, from a layman's interest, is that in the western and northern directions it slopes steeply while it merges gently with soil in the east and south. View from the North is impressive since the rock has retained its original form. The west or north–west view is panoramic and aesthetic, with grayish–white clean plates like appearance (see picture). The rock shines white after

689-510: Is one from a sedimentary rock . Both the BGS and the IUGS use gneissose to describe rocks with the texture of gneiss, though gneissic also remains in common use. For example, a gneissose metagranite or a gneissic metagranite both mean a granite that has been metamorphosed and thereby acquired gneissose texture. The minerals in gneiss are arranged into layers that appear as bands in cross section. This

742-409: Is part of the staple diet of most of the districts of North Karnataka, where it is eaten with pulse curries such as jhunka, yengai, shenga chutney or other assorted chutnies. Jowar rotti is also called as jawarichi bhakri in neighbouring Maharastra. Dharwad peda is a sweet delicacy prepared of milk and sugar which has been accorded Geographical Indication. Hubli-Dharwad Municipal Corporation (HDMC)

795-592: Is probably derived from the Middle High German noun gneist "spark" (so called because the rock glitters). Gneiss is used as a building material, such as the Facoidal gneiss. It's used extensively in Rio de Janeiro . Gneiss has also been used as construction aggregate for asphalt pavement . Dharwar Dharwad (Kannada pronunciation: [ðärwäɖ] )( pronunciation ), also known as Dharwar ,

848-578: Is situated on Gokul Road, 8 kilometres from the city centre and 20 kilometres (12 mi) from Dharwad. It is the third busiest airport in Karnataka and the 45th busiest airport in India . In March 2020, Hubli Airport received the best airport award under the government of India's Regional connectivity scheme. Hubli airport connects to 10 destinations throughout the country. Efforts are being made to make Hubli Airport as international Airport. Mangaluru Samachar

901-506: Is subjected to extreme temperature and pressure and is composed of alternating layers of sandstone (lighter) and shale (darker), which is metamorphosed into bands of quartzite and mica. Another cause of banding is "metamorphic differentiation", which separates different materials into different layers through chemical reactions, a process not fully understood. Augen gneiss , from the German : Augen [ˈaʊɡən] , meaning "eyes",

954-544: The Dharwad Municipal Council first came into existence on 1 January 1856. Both were merged later forming Hubli-Dharwad Municipal Corporation (HDMC) The headquarters of HDMC is situated in Hubballi , comprising 82 members covering four Vidhan Sabha Constituencies of Hubli-Dharwad. There has been a huge demand by the people of Dharwad to create a separate civic body and get itself detached by HDMC. Claims are that most of

1007-677: The Dharwar Group, which are mainly sedimentary in origin, occur in narrow elongated synclines resting on the gneisses found in Bellary district , Mysore and the Aravallis of Rajputana . The supracrustal rocks of the Dharwar Group of the southern Indian Peninsula , as depicted in the geological map of South India , have the Peninsular Gneiss as the basement rock formation, also stated to be

1060-650: The Info box gives exact location). Bengaluru is well connected by road, rail and air with the rest of the country and is also well known internationally. Gneiss Gneisses are common in the ancient crust of continental shields . Some of the oldest rocks on Earth are gneisses, such as the Acasta Gneiss . In traditional English and North American usage, a gneiss is a coarse-grained metamorphic rock showing compositional banding ( gneissic banding ) but poorly developed schistosity and indistinct cleavage . In other words, it

1113-525: The Peninsular Gneiss of the region, dated 2500 to 3400 million years. The Sargur schist belts within the Peninsular Gneiss could be the oldest suture zones in the Indian subcontinent . Lalbagh established by Hyder Ali based on Mughal Gardens at Sira is not only a famous botanical garden but has also a historical link. The creation of the Bengaluru city in the 16th century is attributed to Kempegowda,

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1166-852: The Peninsular Gneisses of Bengaluru. Recent studies carried out with precision techniques indicate that the gneisses have accreted in the following major episodes. b) In the Dharwar Craton studies done on the trondhjemites of Holenarsipur, major crust forming event are attributed through the Rb–Sr whole rock isochron ages. c) In Karighatta – Kunigal areas also, a similar age is indicated. In this case, data of U–Pb SHRIMP of Zircons from amphibolite facies gneisses from Kobaladurga and Kober single zircon evaporation ages of grey gneisses have been considered Thus, three major episodes, namely, 3.4 Ga., 3.3–3.2 Ga., and 3.0–2.9 Ga ., are accreted to form

1219-403: The amphibolite or granulite facies. These form most of the exposed rock in Archean cratons . Gneiss domes are common in orogenic belts (regions of mountain formation). They consist of a dome of gneiss intruded by younger granite and migmatite and mantled with sedimentary rock. These have been interpreted as a geologic record of two distinct mountain-forming events, with the first producing

1272-538: The appearance of an intrusive rock such pegmatite , aplite , or granite the ( leucosome ). The rock may also contain a melanosome of mafic rock complementary to the leucosome. Migmatites are often interpreted as rock that has been partially melted, with the leucosome representing the silica-rich melt, the melanosome the residual solid rock left after partial melting, and the mesosome the original rock that has not yet experienced partial melting. Gneisses are characteristic of areas of regional metamorphism that reaches

1325-721: The best writers in Kannada, and has many iconic places that bear an association with the Language and State’s Culture. Karnataka Vidyavardhaka Sangha also played a crucial role in bringing literary enthusiasts together. Places such as Sadhankeri in front of Varakavi D R Bendre’s house is that serene location from which the poet drew inspiration to write his poems. Dharwad has the reputation of earning 3 (out of 8) Jnanpith Awardees in Karnataka. Da Ra Bendre, V.K. Gokak, Girish Karnad. D V Halbhavi established Halbhavi School of Art, Dharwad which has

1378-416: The bottom of the deck in the other direction. These forces stretch out the rock like a plastic , and the original material is spread out into sheets. Per the polar decomposition theorem , the deformation produced by such shearing force is equivalent to rotation of the rock combined with shortening in one direction and extension in another. Some banding is formed from original rock material (protolith) that

1431-436: The city as per the 1991 census was 7 lakhs. The population of Hubli-Dharwad is 943,857 according to 2011 Census. There has been a huge demand by people of Dharwad to create a separate civic body and get itself detached by HDMC. Claims are that most of the funds are allocated to Hubli solely. Hubli is well known as a commercial as well as an industrial centre, whereas Dharwad is the seat of learning. Popularly believed that, it

1484-560: The city. Karnataka State Cricket Association (ASCA) has organised a few professional district-level and state-level cricket matches in Kittur Rani Chennamma cricket stadium, KCD and SDM cricket ground, Sattur. RN Shetty Stadium stadium has hosted a Ranji Trophy match in 1990 when Karnataka cricket team played against Hyderabad cricket team. Major kabaddi matches are usually held at the Karnatak college ground . Tennis has been

1537-478: The cross-sections ranging from 44 to 35 m (144 to 115 ft). The BRTS corridor includes segregated bus lanes, access-controlled bus stations, physical and fare integration with BRT feeder services, off-board ticketing through smart cards and bar-coded paper tickets, an intelligent transport system and high-quality buses (Standard AC buses). The corridor is designed for operating regular and express services. It consists of two lanes for BRTS buses on either side of

1590-402: The direction of greatest compression, also called the shortening direction, as platy minerals are rotated or recrystallized into parallel layers. A common cause of nonhydrodynamic stress is the subjection of the protolith (the original rock material that undergoes metamorphism) to extreme shearing force, a sliding force similar to the pushing of the top of a deck of cards in one direction, and

1643-722: The distinction of being Karnataka’s first school of Arts in the year 1935. The school, which was founded under the aegis of the Dharwad Fine Art Society, has provided Art education to thousands of students during the last 76 years. The school also introduces students to complementary fields such as theatre, literature, and music. Kumareshwara Fine Arts College (1991) was founded by K.N. Neglurumatha at Haveri. V.R. Sutar started Gangambika Memorial Art School (1993) at Dharwad. Apart from this in 1966, Dandavathi Math in Dharwad opened an Arts School for mentally challenged children. Recognizing

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1696-505: The dominant system of South India in the pictured Geological Map of India. In most stratigraphic schemes, the peninsular gneisses are shown as the younger Archaean strata situated above the Sargur Group. Granitization of the older sedimentary –volcogenic sequence are reported as sources of the peninsular gneisses made up of polyphase migmatites , gneisses and granites ranging in composition from granodiorite to tonalite. The rocks of

1749-525: The form of enclaves. The research information of the geological record of the gneisses, collated and reported in the publication "Geological Monuments of India" published by the Geological Survey of India , is quoted below to provide an undiluted version. A common enclave is a dark grey to black rock called amphibolite containing the minerals plagioclase feldspar and hornblende . Due to interactions with granite fluids, these enclaves have developed

1802-760: The fort was taken by the Mughal emperor Aurangzeb , and Dharwad, on the break-up of the Mughal empire, fell under the sway of the Maratha Peshwa of Pune . In 1764, the province was overrun by Hyder Ali of the Mysore , who in 1778 captured the fort of Dharwad. The fort was retaken in 1791 by the Marathas. After the final defeat of the Peshwa by the British in 1818, Dharwar was incorporated into

1855-569: The funds are allocated to Hubli solely. Hubballi-Dharwad BRTS (also known as HDBRTS) is a bus rapid transit system built to serve the twin cities of Hubli and Dharwad, located in the North-Western part of Karnataka state in India. Hubli-Dharwad BRTS (HDBRTS) project is a Government of Karnataka initiative to foster long-term economic growth in the region. The project promotes fast, safe, comfortable, convenient and affordable public transportation between

1908-582: The granite basement and the second deforming and melting this basement to produce the domes. However, some gneiss domes may actually be the cores of metamorphic core complexes , regions of the deep crust brought to the surface and exposed during extension of the Earth's crust . The word gneiss has been used in English since at least 1757. It is borrowed from the German word Gneis , formerly also spelled Gneiss , which

1961-543: The immense contribution of Dharwad towards the Music, Literature, and Arts field, Central Government has decided to set up Lalitha Kala Akademy Regional Centre in Dharwad. The Lalitha Kala Akademy will act as a catalyst for artists to get equal exposure as some of the bigger cities artists get and will make Art Field more vibrant in North Karnataka region. Jolada rotti is a very popular and very common diet in Dharwad city it

2014-417: The median bus station facilitating overtaking lanes for express services. Foot overbridges at six locations, PELICAN signals, and synchronised signal management are proposed to facilitate the easy approach of passengers to bus stations. Hubli Airport ( IATA : HBX , ICAO : VOHB ) is the nearest airport that serves the twin cities of Hubli-Dharwad and North Karnataka in the state of Karnataka , India. It

2067-521: The middle amphibolite to granulite metamorphic facies . In other words, the rock was metamorphosed at a temperature in excess of 600 °C (1,112 °F) at pressures between about 2 to 24 kbar . Many different varieties of rock can be metamorphosed to gneiss, so geologists are careful to add descriptions of the color and mineral composition to the name of any gneiss, such as garnet-biotite paragneiss or grayish-pink orthogneiss . Continental shields are regions of exposed ancient rock that make up

2120-608: The monsoon season, with moderate temperatures and a large amount of precipitation. Temperatures are fairly moderate from late October to early February, with virtually no rainfall. Dharwad is 750 meters above sea level . The average yearly rainfall is 838 mm (33.0 in). The population of the twin cities as per provisional figures of Census 2011 is 943,857 and is urban. Hubli-Dharwad's population increased 22.99% between 1981 and 1991, from 527,108 to 648,298, and by 21.2% between 1991 and 2001. The Hubli-Dharwad municipality covers 213 km (82 sq mi). Dharwad has earned

2173-527: The rains and attracts attention of the visitors who excitedly climb the rock mass to the tower at the top to get a panoramic view of the gardens and the city. The monument, located in the southern part of Bengaluru, 4 kilometres (2 mi) from the Legislature office complex of the Karnataka Government ( Vidhana Soudha ) within the Lalbagh gardens is easily approachable by road (Metro Map of the city in

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2226-432: The remobilized basement. Migmatization of pre-existing metasedimentary and meta– igneous rocks are considered the contributors to formation of the composite gneiss . The Lalbagh hill, which has been declared as a Geological Monument (plaque pictured) to represent the Peninsular Gneiss, has dark biolite gneiss of granitic to granodioritic composition containing streaks of biolite. Remnants of older rocks are seen in

2279-423: The reputation of being called as 'Cultural Capital of Karnataka'. Dharwad Region's Cultural Life blossomed with some of the finest Poets, Writers, and Thinkers at the beginning 20th century. Hindustani Classical Music is a genre that inspires a possessive devotion among people from the region. Dharwad city is known for karnatic music, art, culture, musicians, poets, writers and cuisine. Dharwad has nurtured some of

2332-596: The stable cores of continents. The rock exposed in the oldest regions of shields, which is of Archean age (over 2500 million years old), mostly belong to granite-greenstone belts. The greenstone belts contain metavolcanic and metasedimentary rock that has undergone a relatively mild grade of metamorphism, at temperatures of 350–500 °C (662–932 °F) and pressures of 200–500 MPa (2,000–5,000 bar). The greenstone belts are surrounded by high-grade gneiss terrains showing highly deformed low-pressure, high-temperature (over 500 °C (932 °F)) metamorphism to

2385-481: The territory of the British East India Company 's Bombay Presidency . During the early 19th century, when the British were expanding their domains, they faced a lot of opposition from local rulers, including Baba Saheb of Nargund and Kittur Chennamma . Hubli-Dharwad has a tropical wet and dry climate . Summers are relatively mild and dry, lasting from late February to early June. They are followed by

2438-462: The then feudal leader under the feudatory of the Vijayanagara empire , who established four cardinal towers setting limits to the growth of the city. One of the towers at the southern end of the city is the Lalbagh tower erected over the Lalbagh hill which is made up of Peninsular Gneiss, now identified as a National Geological Monument. The city has outgrown the limits set by Kempegowda many times and

2491-514: The twin cities and aims to reduce congestion and air pollution in the region. But it has severely affected the private traffic, by restricting the lanes. Many don't approve the project, as BRTS system has failed in many cities across India, for example both in Pune and Delhi. The length of the Hubli-Dharwad BRTS corridor is 22.25 km (13.83 mi) from CBT Hubli to CBT–Dharwad with the width of

2544-471: Was annexed to his dominions. Adil Shah built a fort in an area later called Manna Killa, and later Nazratabad. With this fort, the strategic importance of Dharwad increased and it attracted the attention of subsequent conquerors, including Aurangzeb , Chatrapati Shivaji Maharaj , Aurangzeb's son Bahadur Shah I , Peshwa Balaji Baji Rao , Hyder Ali , Tipu Sultan and finally the British colonizers. In 1685,

2597-471: Was annexed to the newly established Hindu kingdom of Vijayanagar , an official of which named "Dharav", according to local tradition, built the fort at Dharwad town in 1403. After the defeat of the king of Vijayanagar in the Battle of Talikota (1565), Dharwad was for a few years practically independent under its Hindu governor; but in 1573 the fort was captured by the sultan of Bijapur , Adil Shah , and Dharwad

2650-484: Was constituted in 1962 by combining the two cities separated by a distance of 20 kilometres. The area covered by the corporation is spread over 45 revenue villages and is the second-largest city corporation in Karnataka state. The population of the city as per the 1991 census was 700,000. The population of Hubli-Dharwad is 1,158,000 (2020). Hubli Municipal Council was established under the Government of India Act 1850 , and

2703-512: Was converted into grey biotite gneiss during migmatization. The grey biotite gneiss during migmatization was first intruded by grey porphyritic granite and later by pink granites. Pegamatities of several generations have traversed all these rocks. Initial studies on the Gneiss samples of the Lalbagh hill and other locations in Bengaluru, carried out in the early 1970s, have attributed two major events of 2.9 –3.0 Ga and 2.5 Ga −2.6 Ga for development of

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2756-449: Was selected for solar city / green city master plans. In 2017, government of India included Hubli-Dharwad city for a smart city project , a flagship scheme for overall development of infrastructure in the twin-cities. The word "Dharwad" is derived from the Sanskrit word 'dwarawata', 'dwara', meaning "door" and 'wata' or 'wada' meaning "town." It means a place of rest in a long travel or

2809-444: Was the first ever Kannada language newspaper distributed in Dharwad, along with region of North Canara . In current times the newspapers include Vijaya Karnataka , Vijayavani , Kannada Prabha , Prajavani and Samyukta Karnataka, in Kannada; The Hindu , Times of India , Deccan Herald and The Indian Express in English. Cricket and football are the most popular sports in Dharwad and are often played on grounds and streets of

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