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Dharwar Craton AI simulator
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Dharwar Craton
The Dharwar Craton is an Archean continental crust craton formed between 3.6 and 2.5 billion years ago (Ga), which is located in southern India and considered the oldest part of the Indian peninsula.
Studies in the 2010s suggest that the craton can be separated into three crustal blocks since they show different accretionary history (i.e., the history of block collisions). The craton includes the western, central and eastern blocks and the three blocks are divided by several shear zones.
The lithologies of the Dharwar Craton are mainly TTG (Tonalite-trondhjemite-granodiorite) gneisses, volcanic-sedimentary greenstone sequences and calc-alkaline granitoids. The western Dharwar Craton contains the oldest basement rocks, with greenstone sequences between 3.0 and 3.4 Ga, whereas the central block of the craton mainly contains migmatitic TTG gneisses, and the eastern block contains 2.7 Ga greenstone belts and calc-alkaline plutons.
The formation of the basement rock of the Dharwar Craton was created by intraplate hotspots (i.e., volcanic activities caused by mantle plumes from the core-mantle boundary), the melting of subducted oceanic crust and the melting of thickened oceanic arc crust. The continuous melting of oceanic arc crust and mantle upwelling generated the TTG and sanukitoid plutons over the Dharwar Craton.
As the Dharwar Craton is located in southern India, it is geographically surrounded by the Arabian Sea, the Deccan Trap, the Eastern Ghats Mobile Belt and the Southern Granulite Belt.
Traditionally, the Dharwar Craton includes the western block and eastern block. The mylonite zone at the eastern boundary of the Chitradurga greenstone belt is the margin between the western block and the eastern block. The Chitradurga greenstone belt is an elongated linear supracrustal belt which is 400 km long from North to South.
Cratonisation is an important process to form a craton with sufficient and stable continental masses. In terms of the ages of the blocks, the western blocks is older with a cratonisation age around 3.0 Ga while the eastern block is younger with the cratonisation age around 2.5 Ga.
TTG rocks are intrusive rocks with a granitic composition of quartz and feldspar but contain less potassium feldspar. In Archean craton, TTG rocks are usually present in batholiths formed by plate subduction and melting. Two kinds of gneisses can be found on the Dharwar Craton, which includes the typical TTG-type gneisses (i.e., traditional TTG with a major component of quartz and plagioclase) and the dark grey TTG banded gneisses (relatively more potassium feldspar than typical TTG gneisses):
Dharwar Craton
The Dharwar Craton is an Archean continental crust craton formed between 3.6 and 2.5 billion years ago (Ga), which is located in southern India and considered the oldest part of the Indian peninsula.
Studies in the 2010s suggest that the craton can be separated into three crustal blocks since they show different accretionary history (i.e., the history of block collisions). The craton includes the western, central and eastern blocks and the three blocks are divided by several shear zones.
The lithologies of the Dharwar Craton are mainly TTG (Tonalite-trondhjemite-granodiorite) gneisses, volcanic-sedimentary greenstone sequences and calc-alkaline granitoids. The western Dharwar Craton contains the oldest basement rocks, with greenstone sequences between 3.0 and 3.4 Ga, whereas the central block of the craton mainly contains migmatitic TTG gneisses, and the eastern block contains 2.7 Ga greenstone belts and calc-alkaline plutons.
The formation of the basement rock of the Dharwar Craton was created by intraplate hotspots (i.e., volcanic activities caused by mantle plumes from the core-mantle boundary), the melting of subducted oceanic crust and the melting of thickened oceanic arc crust. The continuous melting of oceanic arc crust and mantle upwelling generated the TTG and sanukitoid plutons over the Dharwar Craton.
As the Dharwar Craton is located in southern India, it is geographically surrounded by the Arabian Sea, the Deccan Trap, the Eastern Ghats Mobile Belt and the Southern Granulite Belt.
Traditionally, the Dharwar Craton includes the western block and eastern block. The mylonite zone at the eastern boundary of the Chitradurga greenstone belt is the margin between the western block and the eastern block. The Chitradurga greenstone belt is an elongated linear supracrustal belt which is 400 km long from North to South.
Cratonisation is an important process to form a craton with sufficient and stable continental masses. In terms of the ages of the blocks, the western blocks is older with a cratonisation age around 3.0 Ga while the eastern block is younger with the cratonisation age around 2.5 Ga.
TTG rocks are intrusive rocks with a granitic composition of quartz and feldspar but contain less potassium feldspar. In Archean craton, TTG rocks are usually present in batholiths formed by plate subduction and melting. Two kinds of gneisses can be found on the Dharwar Craton, which includes the typical TTG-type gneisses (i.e., traditional TTG with a major component of quartz and plagioclase) and the dark grey TTG banded gneisses (relatively more potassium feldspar than typical TTG gneisses):
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