Proposed Title 1: - Queen's University

separated by fracturing events in the Cenex deposit that is located east of the Cinch Lake
deposit. Joubin (1955) and Johns (1970) proposed a surficial origin for U mineralization
and suggested that most of the pitchblende occurrences formed near the unconformity
between the Tarzin and Martin Lake groups. Sassano et al. (1972) proposed a
metamorphic hydrothermal source for the fluids and U based on studies of the Eldorado
mine, wherein the deposits were generated by pore fluids in the supracrustal rocks and
remobilized during metamorphism. Tortosa (1983) proposed a groundwater source for the
mineralizing fluids that circulated through fracture zones near the surface and leached U
from rocks to form the orebody at temperatures near 250 o C. Isotopic and
microthermometric studies on silicate, carbonate, and oxide gangue minerals associated
with U-oxide minerals from the Athabasca Basin and Beaverlodge area indicate that fluids
involved with formation of unconformity-type and complex vein-type U mineralization
were saline (10-40 wt % NaCl) having δ 18 O values ranging from -27 to -3 per mil and
temperatures between 150 o C and 220 o C, but variably overprinted by relatively modern
meteoric fluid processes (Peiris and Parslow, 1988; Kotzer and Kyser, 1995).
3.3. Methodology
Polished thin sections were prepared for 550 samples from outcrop and core of most
of the major deposits (Fig. 3.2) and were examined using transmitted and reflected-light
microscopy to determine mineral crosscutting relationships and develop a detail
paragenesis for the Beaverlodge district (Fig. 3.3).
Electron microprobe analysis of syn-ore chlorite and uraninite were accomplished
on polished thin sections using a Cambax MBX electron microprobe equipped with 4
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