Proposed Title 1: - Queen's University

derived from their chlorite crystal chemistry. The age of 1820 Ma is interpreted from U-Pb
geochronology of paragenetically constrained U 1 .
4.5.1.2.1. Pre-ore basement hydrothermal alteration
The pre-ore alteration of the cherty ferruginous shale of the Koolpin Formation is
characterized by the occurrence of 0.1 to 1 cm-wide comb-textured Qtz 1 quartz veins (Fig.
4.9A). Crosscutting relationships indicate that Qtz 1
quartz veins predate massive
brecciation associated with pervasive Src 1 sericite alteration that fills and cements the pore
space between brecciated fragments (Fig. 4.9B). Src 1 sericite is replaced by Chl 1 chlorite
(Fig. 4.9C). Chl 1 chlorite also forms radially-textured laths around Qtz 1 quartz (Fig. 4.9D).
Their size and texture indicate growth into open pore spaces that were possibly created by
brittle deformation. Hem 1 hematite alteration is pervasive. The pre-ore assemblage includes
Ap 1 apatite (Fig. 4.9C), minor Mzn 1 monazite, Ttn 1 titanite, Cpy 1 chalcopyrite and Py 1
pyrite disseminated in the matrix in the most altered samples.
4.5.1.2.2. Pre-ore diagenetic alteration of the Coronation sandstone
Detrital minerals in well-sorted, quartz-dominated sandstones of the Coronation
sandstone consist of rounded Qtz 0 quartz grains and granite fragments (Fig. 4.10A), altered
Mzn 0 monazite (Fig. 4.10B), fragmented and altered Tur 1 tourmaline (Fig. 4.10C) and
altered Ms 0
muscovite laths (Fig. 4.10D). Diagenesis of the Coronation sandstone is
indicated by the occurrence of thin, discontinuous veneers of dark red-brown Hem 2
hematite (Fig. 4.10C) and well developed Qtz 2 quartz overgrowths that outline detrital Qtz 0
quartz grains (Fig. 4.10C).
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