Dharwar Craton

The location map of the Dharwar Craton. The shaded area represents the Dharwar Craton. Generated from GeoMapApp (Ryan et al., 2009).[1]

The Dharwar Craton is an Archean continental crust craton formed between 3.6-2.5 billion years ago (Ga), which is located in southern India and considered the oldest part of the Indian peninsula.[2]

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).[2] The craton includes the western, central and eastern blocks and the three blocks are divided by several shear zones.[2][3]

The lithologies of the Dharwar Craton are mainly TTG (Tonalite-trondhjemite-granodiorite) gneisses, volcanic-sedimentary greenstone sequences and calc-alkaline granitoids.[1] The western Dharwar Craton contains the oldest basement rocks, with greenstone sequences between 3.0-3.4 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.[4]

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.[2] The continuous melting of oceanic arc crust and mantle upwelling generated the TTG and sanukitoid plutons over the Dharwar Craton.[5][6]

  1. ^ a b Jayananda, M.; Peucat, J.-J.; Chardon, D.; Rao, B. Krishna; Fanning, C.M.; Corfu, F. (April 2013). "Neoarchean greenstone volcanism and continental growth, Dharwar craton, southern India: Constraints from SIMS U–Pb zircon geochronology and Nd isotopes". Precambrian Research. 227: 55–76. Bibcode:2013PreR..227...55J. doi:10.1016/j.precamres.2012.05.002. hdl:1885/71644.
  2. ^ a b c d M., Jayananda; M., Santosh; K.R., Aadhiseshan (June 2018). "Formation of Archean (3600–2500 Ma) continental crust in the Dharwar Craton, southern India". Earth-Science Reviews. 181: 12–42. Bibcode:2018ESRv..181...12J. doi:10.1016/j.earscirev.2018.03.013. S2CID 243889151.
  3. ^ Peucat, Jean-Jacques; Jayananda, Mudlappa; Chardon, Dominique; Capdevila, Ramon; Fanning, C. Mark; Paquette, Jean-Louis (April 2013). "The lower crust of the Dharwar Craton, Southern India: Patchwork of Archean granulitic domains". Precambrian Research. 227: 4–28. Bibcode:2013PreR..227....4P. doi:10.1016/j.precamres.2012.06.009.
  4. ^ Lancaster, Penelope J.; Dey, Sukanta; Storey, Craig D.; Mitra, Anirban; Bhunia, Rakesh K. (December 2015). "Contrasting crustal evolution processes in the Dharwar craton: Insights from detrital zircon U–Pb and Hf isotopes". Gondwana Research. 28 (4): 1361–1372. Bibcode:2015GondR..28.1361L. doi:10.1016/j.gr.2014.10.010.
  5. ^ Cite error: The named reference :14 was invoked but never defined (see the help page).
  6. ^ Jayananda, M.; Chardon, D.; Peucat, J.-J.; Fanning, C.M. (October 2015). "Paleo- to Mesoarchean TTG accretion and continental growth in the western Dharwar craton, Southern India: Constraints from SHRIMP U–Pb zircon geochronology, whole-rock geochemistry and Nd–Sr isotopes". Precambrian Research. 268: 295–322. Bibcode:2015PreR..268..295J. doi:10.1016/j.precamres.2015.07.015. hdl:1885/98524.