The geology of the Mangana-Waterhouse goldfields : with particular reference to structure and mineralisation
thesisposted on 2023-05-27, 12:13 authored by Threader, VM
Ttie study covers an area of approximately 300 square miles and incorporates eight defunct goldfields in the northeast of Tasmania. The principal rock unit in the area mapped is the Mathinna Beds which is the host rock of the mineralisation. The Mathinna Beds consists of a lower lutite member and an upper predominantly arenite unit. Both units exceed l,000 feet thickness in the area mapped but total thickness is unknown. The main fold structure strikes NNW - SSE with a wavelength of the order of 2 miles on which is superimposed folding on several smaller scales. Two directions of shearing are recognised: one striking parallel to the folding and one at right angles to it. The former is in part contemporaneous with the folding and the latter is mainly of later age but evidence suggests that recurrent movements on both sets have occurred. The later shearing movements (ENE - WSW) are considered to have given rise to several major lineaments with which later igneous activity and epeirogenic movements have been associated. Gold mineralisation is related to a major shear zone and does not appear to bear any direct relationship to granite masses nor to fold structures. It is recommended that future exploratory work be confined to the shear zone and several lines of research are suggested as a means of locating areas of mineral concentrations in this zone. Attention is also drawn to the gold producing potential of the extensive alluvial plains of the major watercourses.
Rights statementCopyright 1967 the author - The University is continuing to endeavour to trace the copyright owner(s) and in the meantime this item has been reproduced here in good faith. We would be pleased to hear from the copyright owner(s). Thesis (MSc) - University of Tasmania, 1968. Includes bibliography