Fabric evolution in Salem-Attur Shear Zone, South India, and its implications on the kinematics

• Published in: Gondwana research Vol. 16; no. 1; pp. 37 - 44
• Main Authors: Kumar, R. Satheesh, Prasannakumar, V.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-08-2009
• Subjects: Fabric rotation; S-C fabrics; Salem-Attur shear; Shear indicators; Strain-partitioning; Salem-Attur shear; Shear indicators; S-C fabrics; Fabric rotation; Strain-partitioning
• ISSN: 1342-937X; 1878-0571
• DOI: 10.1016/j.gr.2008.10.006

Domains of opposing shear-sense, relative to the overall kinematic framework, often add to the ambiguities in the interpretation of movement picture along major shear zones. Rheologic properties, strain partitioning as well as rotation of fabric are the principal mechanisms that contribute to the evolution of fabric during shearing. The relative dominance of these mechanisms varies with progressive strain, leading to the development of domainal fabric departing from the regional stress–strain vectors. The Salem-Attur Shear Zone exhibits imprints of multiphase shearing and domains of meso- to micro-fabrics indicating opposing shear sense, resulting in conflicting interpretations of the regional kinematics. Since the sense of movement is a major constraint in matching the shear zones in Gondwana fragments, this paper focuses on understanding the movement picture of the shear zone and the mechanism of evolution of domainal fabric.