Abstract
The Etam shear zone is the NNE-SSE to NE-SW trending fault zone with coexistence of a sinistral shearing mylonitic corridor and a brecciated quartz vein. The mylonitic zone is evidence of progressive deformation. Primary minerals include Qtz1 + Kfs1 + Pl1 + Bt1. These minerals increasingly and gradually reduce from the wall rock towards the shear zone center. Quartz recrystallization also gradually increases in the same direction. Microstructures observed include: recrystallization, sub-grain boundary, myrmekites and undulose extinction. Mica-chlorite-epidote assemblages define the greenschist assemblage, but the observation of amphibole in the mylonite and the presence of flame perthite in feldspar suggest a transitional greenschist-amphibolite metamorphic condition in the Etam Shear Zone. The brecciated quartz vein has dimensions of about 2.5 × 0.5 km and shows several quartzitic blocks, mainly composed of milky to transparent quartz clasts and a siliceous matrix. Quartz clasts are pure and the observation of thin sections of these quartz under polarized microscope shows grains free of microstructures or displays small micro quartz veins and rare feldspar inclusions. These are some criteria, which can lead to a preliminary assessment of the purity of quartz in Etam area.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
