3.35Ga komatiite volcanism in the western Dharwar craton, southern India: Constraints from Nd isotopes and whole-rock geochemistry

U–Pb and Lu–Hf Systematics of Zircons from Sargur Metasediments, Dharwar Craton, Southern India:New Insights on the Provenance and Crustal Evolution

“…113, NO. 7, 10 OCTOBER 20171395 belts) are considered to be younger and deposited between 3 and 2.55 Ga. On the basis of the first U-Pb SHRIMP zircon age data for the detrital zircons, separated from the quartzites of the Sargur Group exposed near Holenarasipur and Banavar, Nutman et al 11 suggested that the sedimentary protoliths of quartzites were derived from a provenance with a minimum age of 3.0 Ga. Jayananda et al 22 and Maya et al 23 reported 3.35 and 3.15 Ga ages respectively, for the komatiitic ultramafic rocks of the Sargur Group. Trendall et al 24 reported U-Pb SHRIMP zircon ages of 2.72 and 2.6 Ga for the metavolcanic rocks of the Bababudan and Chitradurga Groups respectively, of the Dharwar Supergroup.…”

Physical volcanology and geochemistry of Palaeoarchaean komatiite lava flows from the western Dharwar craton, southern India: implications for Archaean mantle evolution and crustal growth

“…The western Dharwar craton preserves 3.4-3.2 Ga TTG (Jayananda et al 2015) and the associated Sargur Group greenstone belts with ca. 3.38-3.15 Ga volcanic sequences and interlayered sediments (quartzite-pelite-carbonate), indicating detrital zircon ages as old as 3.6 Ga for their provenance (Meen et al 1992;Nutman et al 1992;Peucat et al 1993;Bhaskar Rao et al 2008;Jayananda et al 2008). The TTG and associated Sargur Group greenstone sequences form a basement for the younger 2.91-2.67 Ga Dharwar Supergroup greenstone sequences forming the Bababudan-Chitradurga and ShimogaDharwar basins (Kumar et al 1996;Nutman et al 1996;Trendall et al 1997;Jayananda et al 2013b;Manikyamba et al 2014aManikyamba et al , 2014b.…”

“…A pronounced stratigraphic break between the J.C. Pura belt (older Sargur Group) and Kibbanahalli arm (younger Bababudan Group) volcanic-sedimentary sequences has been demonstrated through unconformity defined by Venkata Dasu et al, 1991;Srikantia and Bose, 1985;Jayananda et al, 2008;Maya et al, 2011) Figure 2. Stratigraphic successions of Sargur Group -J.C. Pura and Banasandra greenstone belt (Venkata Dasu et al 1991;Srikantia and Bose 1985;Jayananda et al 2008;Maya et al 2011). Chardon et al 1996) showing sample locations.…”

“…They are often considered to be windows to secular development of dynamic mantle (Mole et al 2014) and are fundamental to our understanding of the thermal, chemical, and tectonic evolution of the early Earth. Since the discovery of komatiites in South Africa (Viljoen and Viljoen 1969), numerous studies conducted on komatiites from southern Africa, Canada, Australia, India, Finland, and Brazil (Jahn et al 1980(Jahn et al , 1982Barnes et al 1988;Arndt 1994;Hill et al 1995;Lesher and Arndt 1995;Fan and Kerrich 1997;Grove et al 1997;Parman et al 1997;Polat et al 1999;Polat and Kerrich 2000;Chavagnac 2004;Barnes 2006b;Arndt et al 2008;Jayananda et al 2008;Dostal and Mueller 2012;Furnes et al 2013;Maier et al 2013), together with experimental works (Ohtani et al 1989;Herzberg and O'Hara 1998), have greatly contributed to our understanding of the origin of both komatiite magmas and Archaean mantle. However, the tectonic context of magma generation and eruption of komatiite magmas is still not fully resolved (Polat et al 1999;Arndt 2003;Parman et al 2004;Arndt et al 2008) although most workers consider komatiite magmas to have originated from anomalously hot mantle upwellings (Nesbit et al 1993, Herzberg 1995Arndt et al 2008), probably analogous to modern mantle plumes.…”

SHRIMP U–Pb zircon ages of granitoids adjacent to Chitradurga shear zone, Dharwar craton, South India and its tectonic implications

“…Dharwar craton of South India represents one of the largest cratonic masses of Indian shield and preserves early crystalline basement rocks ranging in age from Mesoarchean to the early Paleoproterozoic (Peucat et al, 1995;Chadwick et al, 2000;Jayananda et al, 2000Jayananda et al, , 2006Jayananda et al, , 2008Balakrishnan et al, 1999), and covering an area of 4.5 × 10 5 km 2 (Ramakrishnan and Vaidyanadhan, 2010 and references therein). The tectonic context of the continental growth of the Dharwar craton is a subject of debate.…”