Original paper

Ductile shear zones in Erinpura granites and implications for Neoproterozoic geodynamics along the Western Boundary Fault of the Delhi Fold Belt in NW India

Just, Jana; de Wal, Helga; Pandie, Manoj K.; Schulz, Bernhard

Abstract

NW India is one of the key regions for plate tectonic reconstructionsof the I Ga to 750 Ma Rodinia accretion/breakupand the formation of East Gondwana. Within this frame, the Neoproterozoic« 900 Ma) magmatic and tectonic activity along the western flank of the Delhi Fold Belt is controversiallydebated. The Erinpura granite gneisses are deformed at all scales along the Western Boundary Fault of the Delhi Fold Belt and can serve as temporal and structuralmarkers. We attempt to constrain time, kinematics and strain magnitude in the Erinpura granitoid suite by analysis of magnetic fabrics and microstructures in combination with Th-U-Pb dating of monazite. Magmatic and recrystallized monazite is analyzed by the electron-microprobe(EMP-CHIME method) indicating a late Neoproterozoic ductile overprint of the Erinpura granites.