The tectogenesis of the Telfer gold-copper ore system in the Proterozoic Paterson Orogen, north western Australia

Abstract

Tektogeneza złoża rud złota i miedzi Telfar, proterozoiczny orogen Paterson, północno-zachodnia Australia This paper reviews the tectonic genesis of the Telfer Au-Cu ore system in the Paterson Orogen, NW Australia. Most previous tectonic interpretations have focused on the regional compression-related tectonic processes. These interpretations, however, could neither explain the tectonic deformation nor the distribution of mineralisation. Tectogenetic analysis indicates that the Telfer deposit comprises two overlapping structural domains, both developed as a result o f the upward propagation of basement fractures. The first domain represents a local compression-shear-related regime that initiated tectonic deformation and tectonic shortening of the host rock. This regime had a limited role in the mineralising processes. The second, more important regime for mineralisation control, is associated with local shear-extensional tectonic processes. At deposit scale, concurrent development of a normal dip-slip movement along the earlier formed bedding surfaces and the basement propagated steep reverse-slip shearing along NW-SE (S2) trending structures, parallel to the strike of the Paterson Orogen, are the most important tectonic processes of this domain. Bedding surface extensional openings and development of second order structures with N -S (E3) and NW-SE (E2) orientation controlled the tectonic genesis of the majority of orebodies and mineralised zones forming the Telfer ore system.