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Authors
Affiliations
1 Laboratoire Magmas et Volcans, OPGC - Universite Blaise Pascal & CNRS; 5, rue Kessler, 63038, Clermont-Ferrand Cedex, FR
2 Bangalore University, Bangalore - 560 056, Karnataka, IN
3 L.M.T.G., UMR 5563 - University Paul Sabatier & CNRS, 38 rue des 36-Ponts 3 1400 Toulouse, FR
4 Geosciences Rennes Av. du General Leclerc 35042 Rennes cedex, FR
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 62, No 6 (2003), Pagination: 753-768
Abstract
The Dharwar craton exposes a natural cross-section of the continental crust. This crust has been intruded during the Late Archaean by a large volume of granites. One of these is the Closepet Granite, which outcrops at different structural levels from deep (corresponding to palaeopressures of 7-8 Kbar) to shallow (2-3 Kbar) crust. This crosssection allows the study of all components of this granite: the ischolar_main zone, displaying strong crust-mantle interaction, resulting in highly heterogeneous, enclave-rich monzonilic to granitic magmas; the transfer zone, with inferred upward movement of these magmas; and a rheological interface in the shallow crust at which the ascent of the magmas was arrested. At this level, only the less viscous (differenciated and enclave-free) magmas were able to rise through a network of dykes and fill small pockets, forming typical, elliptic granitic intrusions (the "intrusion zone").
Keywords
Granite Provinces, Structural Levels, Granite Emplacement, Syn-Tectonic Granite, Closepet Granite, Karnataka.
