Proposed Title 1: - Queen's University

and saline fluids (Mernagh et al., 1994). Therefore, the occurrence of Au 1 -PGE±U 1
associated with the quartz feldspar porphyry at the Coronation Hill deposit may have
resulted from acid neutralization and moderate reduction resulting from fluid interaction
with feldspathic host rocks (Wyborn, 1992; Mernagh et al., 1994). Ore metal deposition is
therefore, strongly controlled by the composition of the host lithology (e.g. Needham and
Stuart-Smith, 1984; Needham, 1988b)
Our results corroborate Ayres (1975) suggestion that the Au source was the El
Sherana Basin volcanics, particularly the Pul Pul Rhyolite of the Coronation sandstone.
Mernagh et al. (1994) indicated that highly oxidizing, basinal, low temperature and low-pH
solutions transported simultaneously Au, PGE and U as oxy-chloride and chloride species,
but proposed the Kombolgie Basin sediments as the source of the mineralizing fluids. Sener
et al. (2002) suggested that the nature of the ore elements and alteration at the Coronation
Hill deposit is consistent with deposition from acid and oxidizing fluids.
Au and PGE are found in ore grade concentrations in unconformity-related uranium
deposits. For example, U ore in the Jabiluka deposit contains Au grading 10 g/t and
significant concentrations of Pd (Wilde et al., 1989). Unconformity-related U deposits in
the Athabasca Basin in Canada have also been reported to contain minor concentrations of
Au and PGE (Wray et al., 1985).
LA-HR-ICPMS data indicate that initial U precipitation occurred in the basement at
ca. 1820 Ma (Figs. 4.12A to 4.12C). The 1822 Ma chemical Pb age of U 1 uraninite (Fig.
4.14) at Coronation Hill is identical to the U-Pb concordia ages at the El Sherana deposit
(Figs. 4.12A to 4.12C). These ages suggest that the U mineralization in the SAVMF formed
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