Mineralogical report number 9719 by Alan C. Purvis, PhD relating to drillhole LBD-1, Limbunya, for the purposes of Hylogger interpretation

Abstract

The twelve core samples described from normal thin sections in this report are from a single drillhole, labelled LBD-1, drilled by Proto Resources and Investments at Lindeman's Bore, near Limbunya Station in the Northern Territory. Fillets cut from each of the cores were also submitted to AMDEL (20/05/2010) for semi-quantative X-Ray diffraction to compliment the mineralogy determined by optical microscopy, particularly to distinguish clay minerals and precise carbonate species, which cannot always be achieved in this sections only analysis. Offcuts from seven carbonate-rich carbonate-bearing samples also were stained with acidified alizarin red and potassium ferricyanide to give an initial petrographic assessment of calcite and Fe-bearing carbonate species (other than siderite). Notes on logging and HyLogger results were sent with the samples and are incorporated into this report since it is understood that this investigation is largely intended to assist in the assessment of Hylogger results. Minerals identified by the HyLogger include water-bearing and carbonate species, but not sulphides or anhydrous minerals other than carbonates. The information provided and study of the BMR Limbunya Geological sheet indicates that this drillhole has a basement of Inverway Metamorphics, with weathering associated with an unconformity against Stirling Sandstone, a member of the Limbunya Group in the Birrindudu Basin. The Stirling Sandstone is overlain by Pear Tree Dolostone, Amos Knob Formation and Margery Formation claystone. The highest unit in the drillhole is Mallabah Dolostone and silicified equivalent material (the spelling 'Mallabah' is taken from Sweet, 1977).