University of Western Ontario - Electronic Thesis and Dissertation Repository

Degree

Master of Science

Program

Geology

Supervisor

Drs. Robert Linnen and Dazhi Jiang

Abstract

The Whabouchi pegmatite is within a transpressional high-strain zone of a metamorphosed volcano-sedimentary belt. A well-developed subvertical transposition foliation and a subvertical stretching lineation are present in this zone. The main body of the Whabouchi pegmatite is parallel to the transposition foliation and branching veinlets from this body have been folded and boudinaged by shear zone deformation. Thus suggesting that the Whabouchi pegmatite intruded syn-kinematically during the deformation of the shear zone. Previously, the Whabouchi pegmatite gave a zircon age of 2577 + 14Ma. The Whabouchi pegmatite is linked geochemically and geochronologically to a large pegmatite body to the south with a monazite age of 2595 + 14Ma. This suggests that the Whabouchi pegmatite was likely formed by fractionation from a peraluminous granite generated by anatexis. These ages constrain the deformation within the shear zone responsible for the late-stage pegmatite intrusion event between 2595 to 2577Ma during which, the Whabouchi pegmatite was emplaced.