Proposed Title 1: - Queen's University

at ca. 1820 Ma, approximately 40 Myr after initial deposition and diagenesis of the EL
Sherana Basin.
The timing of the U-Au-PGE mineralization at the Coronation Hill at El Sherana
deposits is coincident with a period of regional extension tectonism and granite intrusion in
the Pine Creek Orogen (Ferguson et al., 1980a; Stuart-Smith and Needham, 1984;
Needham et al., 1988). These granites include the 1820±8 Ma Malone Creek Granite
(Edgecombe et al., 2002), which intruded El Sherana Group rocks, the ca. 1820 Ma
calcalkaline Cullen Suite granite intruding the Pine Creek Orogen (Stuart-Smith et al.,
1993) and the 1818±3 Ma Fenton Granite in the Gold Ridge area (Needham et al., 1988).
4.6.3. Late stage alteration and resetting events
Post-ore alteration recorded in uraninite samples indicate that the U-Pb and Pb-Pb
isotopic system in U 1 uraninite and cogenetic Gn 1 galena were reset during multiple fluid
events related to fault reactivation during successive regional thermotectonic events that
occurred over a period of at least 1.8 Gyrs (Figs. 4.15A and 4.16). These alteration events
resulted in subsequent alteration of the El Sherana and Coronation Hill deposits and
formation of the post-ore mineral assemblage including widespread secondary uranium
minerals (Figs. 4.6E and 4.6F) occurring as fracture-filling veinlets (Fig. 4.7A).
The U 1 mineralization records an alteration event at ca. 1720 Ma, consistent with the
timing of the Oenpelli dolerite intrusion of the Kombolgie Basin (Fig. 4.16, Sweet et al.,
1999; Kyser et al., 2000). This event is coincident with the timing of post-ore alteration
event at the Ranger (1737±20 Ma, Ludwig et al., 1985, 1987) and Koongarra U deposits
(1800 Ma to 1700 Ma, Hills and Richards, 1976). Polito et al. (2004) interpreted ages of
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