The Sargur Schist Complex - An Archaean High-Grade Terrain in Southern India

• Main Authors: Janardhan, A. S., Srikantappa, C., Ramaohandra, H. M.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 10.1016/S0166-2635(08)70096-3 1978
• Subjects: Geology; Greenland; Upernavik
• Online Access: http://eprints.uni-mysore.ac.in/13964/; https://www.scopus.com/inward/record.uri?eid=2-s2.0-77956798598&doi=10.1016%2fS0166-2635%2808%2970096-3&partnerID=40&md5=5eb1d63b02e9627b2daf199146a9cacb

The Sargur sohist complex contains Archaean quartzo-feldspathic tonalitic gneisses of mixed origin. and tight to isoolinally folded remnants of quartzite K pelite-carbonate shelf facies sediments. Relics of layered ultramatic-gabbroanorthosite (minor) complexes with cumulate textures occur as discontinuous linear belts, cods and patches in the gneisses and are later than the metasediments. The presence of tincluded' gneiss in an ultramafic body suggests the Sargur supracrustals rested on a gneissic basenent. Carbonate-bearing ultramafios (similar to �sagvandites�) suggest a significant co2 pressure during metamorphism. This possibly explains the local attairment of granulite facies conditions in a predominantly upper amphibolite facies terrain. There were at least two periods of migmeatisation with late (anatectic) granite sheets. Three major defermational episodes are well preserved in the quartzites. There is much similarity between the Sargur complex and the Isua-Malene-Upernavik succession of West Greenland and Labrador. The presence of younger Dharwar greenstone belts to the north and a 'mobile belt' towards the south of the Sargur terrain is similar to relations in southern Africa. However, more coordinated absolute age/isotcpio/rare earth element data are needed before a convincing model can be erected to explain the evolution of the high-grade terrain of southern India. © 1978, Elsevier B.V. All rights reserved.