Deformation style in the Granulite-charnockite province of South India: An example from the Kusulmalai area in Salem district,Tamil Nadu,India |
| |
Authors: | Deepak C Srivastava |
| |
Institution: | (1) Department of Earth Sciences, University of Roorkee, 247667 Roorkee, India |
| |
Abstract: | A multiple-deformation sequence is established for different types of gneisses, mafic-paleosomes and banded magnetite quartzites
(BMQ) exposed within the area. In gneisses, the basin-shaped map pattern represents the type-i interference structure formed
due to the overprinting of F3 folds with ENE striking axial planes on F2 folds with axial planes striking NNW. The BMQ band occurring as an enclave within the gneissic country, represents a large
scale F1 fold with relatively smaller scale F2 folds developed on its limbs. Mafic-paleosomes within the streaky-charnockitic-gneisses exhibit structures formed due to
the interference of more than two phases of folding (F1,Fla,F2,F3). It is shown that the deformation plan in these rocks is consistent with the generalized deformation scheme for Granite-greenstone
belts. The difference in the map pattern of Granite-greenstone belts and Granulite-charnockite terrains is ascribed to the
variance in Theological properties, layerthickness ratios and local displacement directions during different phases of folding.
These differences apart, both the Granite-greenstone and Granulite-charnockite provinces in South India are deformed by an
early isoclinal folding which is successively overprinted by folding on NNW and ENE striking axial planes. |
| |
Keywords: | Granulite-charnockite Granite-greenstone structural analysis gneisses banded magnetite quartzites |
本文献已被 SpringerLink 等数据库收录! |
|