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Dharwar craton is divided into Western (geosynclinal) and Eastern (arc basins) Dharwar cratons (WDC, EDC), having comparable/ correlatable litho-stratigraphic stages. The lithostratigraphy of WDC/ EDC comprises older Sar gur Group/Satyamangalam Group (~31003300 Ma), intruded by Hassan Gneiss/Kammuru (Bhavani) Gneiss (TTG-II, ~3000 Ma, ≡ Peninsular Gneiss – a misnomer in a cratonic extent), developed on a sialic basement of Gorur Gneiss (TTG-I, ~3300 – 3400 Ma); and younger Dharwar/Anantapur Super groups comprising Bababudan and Chitradur ga Groups (~2900 – 2550 Ma) / Mushtikovila (Katrimala / Parampur) Formation ( ≡ Bababudan), emplaced by Cherlopalle (domal) Gneiss ( ≡ Gundlupet Gneiss / Chikmagalur trondhjemite – granodiorite / Halekote trondhjemite, TTG – III, ~ 2800 Ma); and Marutla (Sakarsanahalli) – Kolar (V eligallu) – Hungund (Hutti) Groups ( ≡ Chitradurga, ~2750 – 2550 Ma), intruded by calc – alkaline Atmakuru Granodiorite (arc, I-type, ~2630 – 2580 Ma, ≡ J.N.Kote/Kanara/Bukkapatna etc.), Somravandlapalli (Kadangal) ultramafic – mafic ± anorthosite complex ( ≡ Usgaon / Hanumalapura), and Kuderu (Torangal/Patna/Perur/Gadag) Granite (collisional, S-type, ~2550 – 2510 Ma), resulted in the accretion and stabilization of Archaean continental crust. These litho-groups are intruded by a phase of anaerogenic alkaline granites (V enkatapuram, Gingee, Sholingar etc. ~2250 ± 50Ma) and mafic dyke swarms (Mahabubnagar , A liAnaikatti, MDS-I, ~2160 Ma) synchronous with development of failed rift sedimentary basins. Mesoproterozoic Cuddapah Super group of earlier workers is classified into Palaeoproterozoic Papaghni Super group: Gandi Group – Gulcheru Quartzite, Vempalle Formation (~ 1900 Ma) and Kuppalapalle Formation (~ 1840 Ma); and upper Chitravati Group: Pulivendla Quartzite, Tadpatri Formation and Gandikota Quartzite; emplaced by Kondapuram ultramafic – mafic sills ~1817 Ma ( ≡ Tirupati – Dharmpuri mafic dykes – MDS – II, ~ 1800 – 1750 Ma); and Mesoproterozoic Nallamalai Super group: Cheyair Group – Tirumala (Nagari / Bairenkonda) Quaratzite, Pullampet (Cumbum) Formation and Mangampeta Formation; and upper Srisailam Quartzite (~1327 Ma). The Cheyair Group is intruded by Vellaturu Granite (associated basemetal mineralization – Agnigundala belt, ~1350 – 1400 Ma), alkaline syenites and subalkaline ferro-synites (Racherla syenites), lamproites and ultra-potassic rocks (Jaggayyapeta Lamproites, ~1200 – 1300 Ma), and mafic sills / dykes (T irupati / Tiptur, MDS – IV, ~1000 – 100Ma). Later the Western part of EDC are emplaced by kimberlites and lamprophyres (W ajrakarur Kimberlites, ~1000 – 1100Ma). Both Papaghni (Palaeoproterozoic) and Nallamalai (Mesoproterozoic) basins / Super groups are unconformably overlain by Neoproterozoic Kurnool Group of rocks in Kurnool and Palnad sub-basins. The status of Mesoproterozoic Kaladgi Group – Lokapur and Simikere Subgroups of earlier workers is enhanced to Kaladgi Super gorup – Lokapur and Simikere Groups as per S tratigraphic norms; intruded by a phase of pegmatite/quartz veins and mafic dykes (≡ Tirupati – Tiptur, MDS-IV, ~1000 – 100 Ma); and overlain unconformably by Neoproterozoic Badami Group ( ≡ Bhima Group). The correlation of Vengad Group (/Formation) with Ranibennurs may not be correct and may be equivalent to Kaladgis. Gudur Group – Chaganam and Malakonda Formations (Archaean); Udayagiri Group – Dirsavancha and Nandavaram Formations (Cuddapah cover); and Bairenkonda Quartzite (Mesoproterzoic) of earlier workers constituting the Nellore fold (schist) belt is classified into lower Vinjamuru Group – Saidapuram, Chaganam and Malakonda Formations; and upper Udayagiri Group – Duttaluru, Sitarampuram Formations and Kondamidapalli Quartzite, clubbed under Nellore Super group (Palaeoproterozoic, ≡ Papaghni Super g oup), intruded by Pamur/Vinukonda Granite (~ 1615 ± 25 Ma) and mica pegmatites and quartz veins (~1630 ±100 Ma) and mafic dykes (Anantapur Karimnagar – Tiruvannamalai, MDS-III (~1600 – 1650 Ma). The Supracrustal rocks of Khammam Schist belt – Khammam Group are equivalent to Vinjamuru Group of Nellore Super group. Eastern Ghats Super group – Khondalite, Charnockite and Migmatite Groups (Archaean to Palaeoproterozoic, G .S.I, 2015) comprising the EGMB is classified into Palaeoproterozoic Eastern Ghats Group – Koraput (Khondalite) Subgroup and Ongole (mafic granulites) Subgroup; intruded by Jeypore Charnockite (Phase-I, ~ 1700 Ma, 1640 Ma); later by ultramafic – mafic ± anorthsite/gabbro – anorthosite complexes/ gabbro / anorthosites (Kondapalli ( ≡ Chimalpahad) / Chimakurti etc); Prakasam alkaline complex (Kunavaram, Elchuru, Khariyar , Koraput etc., nepheline syenites (~1500 – 1240 Ma) and nonfeldspathoidal alkaline granites and syenites (Kanigiri, Podile, Darsi etc.) and Bobbili Charnockite (Rapakivi, Orbicular , Phase-II, ~1000 – 1 100Ma); and Bolangir , Turkel, Chilka Lake etc., anorthosite complexes (<950 – 800 Ma). It may be equivalent to Nellore Super group, forming paired – metamorphic belts. Pakhal Super group-Mallampalli and Mulug (V enkatapuram) Groups, constituting the Pakhal fold belt, correlated with Papaghni – Chitravati Groups and Nallamalai Group of Cuddapah Super group respectively may not be correct; and is equivalent to Mesoproterozoic Nallamalai / Kaladgi Super g oups. The litho-ensemble (two volcano – sedimentary cycles) of Pandyan mobile belt (PMB) are tentatively classified under Pandyan Super group – Dindigul Group (arenite dominant – Madurai Block), and Nanguneri Group (Pelite dominant – Trivandrum Block), emplaced by Kodaikanal (Nagercoil) Charnockite (Phase-I); later by Sittampundi, Bhavani etc., ultramafic – mafic ± anorthosite complexes in the mar ginal zone (≡ Chimalpahad); and Kadavur , Oddanchatram, Manapparai gabbroanorthosite complexes in PMB (Mesoproterozoic); and alkaline granites and syenites ± carbonatites in the mar gin l zone and PMB (Neoproterozoic – Pan African). Pandyan Supegroup may be equivalent to Palaeoproterozoic Papaghni/Nellore/Eastern Ghats Super group/Group. The tectonic scenario in the Dharwar craton and adjoining fold and mobile belts is controlled by two distinct orogenies – Dharwar and Eastern Ghats, separated by Eparchaean unconformity (~2500 to 2200 Ma). The former comprises Sar gur (~ 3000 Ma), Bababudan (~ 2800 Ma) and Chitradur ga (~ 2600 – 2500 Ma) deformations, whereas the latter by Nellore (Î Papaghni, ~ 1700 – 1600 Ma), Nallamalai (~1400 – 1350 Ma) and Kurnool (/Dharmapuri < 1000 – 500 Ma) deformations. Early dominant pure shear regime (~3400 – 2600 Ma) followed by transpressive shear regime (~ 2600 – 2500 Ma) of Dharwar orogeny , resulted in the accretion and stabilization of Archaean continental crust (~2500 Ma). Eparchaean unconformity (~2500 – 2200 Ma) represents Archaean Proterozoic S tructural Inversion APSI i.e. Archaean transpressive shear regime taken over by Proterozoic transtensional shear regime (~2200 – 500 Ma) leading supercontinental accretion and their agglomeration with cratonic areas – Eastern Ghats Orogeny .

Precambrian lithostratigraphy of Dharwar craton and adjoining fold and mobile belts