The Cadjebut Ore-Body

Abstract Cadjebut was the first operating underground MVT mine in Australia. The ore occurs as two lenticular, stratabound lenses extending 2km eastsoutheast along strike, with widths varying from 50 to 1 SOm and a thickness from 3 to 6m per lens. Ore occurs within the lower dolomite near the base of the platform facies rocks of the Pillara Limestone (Figs 4.1 and 4.2). The two ore lenses are separated by 5 to 6m of low-grade mineralization or barren impure dolomites. High-grade Zn ore is stratiform and rhythmically banded in the lenses. Texturally post-dating the rhythmically banded ore is breccia ore. Breccia ore occupies open spaces and is the matrix to large breccia blocks of dolomite and rhythmically banded ore. The main descriptions of the Cadjebut ore-body are by Tompkins (1994) and Tompkins et al. (1 994a, 1994b). Copies of research papers on Cadjebut arizing from this project are appended to this report. The following text summarizes the geology of Cadjebut and outlines some problems. Most of this chapter is based on follow-up work, completed after L. Tompkins had completed her PhD thesis and is designed to provide a description of Cadjebut compatible with the results of the rest of the report. For a detailed description of the deposit and interpretation of geochemical results the reader is referred to the above thesis and research papers by L. Tompkins.