Steven Siemieniuk's Honours thesis abstract

Thesis Title: 
Alteration and Gold Mineralization of the Jubilee Zone at the Elora Property, Dryden, Ontario

The Elora Property hosts to two past producing gold mines and is located roughly three kilometers from the historical town of Goldrock on the northeastern end of Upper Manitou Lake. The Elora Property lies in the western portion of the Wabigoon Subprovince in the Manitou-Stormy Lakes metavolcanic-metasedimentary belt. The property falls mostly within the tholeiitic to calc-alkaline, predominantly metavolcanic flows of the Pincher Lake Group rocks; except for the westernmost part of the claims, which lie within the stratigraphically lower calc-alkaline, predominantly pyroclastic metavolcanic rocks of the Upper Manitou Lake Group.

Transmitted light microscopy combined with whole-rock, trace-element, and rare earth element geochemical data were used to identify the principal rock units and associated hydrothermal alteration assemblages proximal to gold mineralization at the Jubilee Zone. Timing of gold mineralization was also characterized in the Jubilee Zone.

Mafic metavolcanic rocks were continuous into the section of drill core studied, whereas rocks logged as metasedimentary could not be conclusively identified as such. However, the presence of pyrrhotite, fine grained carbonaceous material, a lack of gold mineralization, and primitive mantle plots contrasting with those of mafic metavolcanic rocks all suggest that there is a lithological contrast of some sort with the mafic metavolcanic rocks. However, it is unclear what the protolith of these rocks was.

On the scale of the geochemical study there were no reliable vectors to gold mineralization. Na2O was the only element that displayed a noticeable and somewhat gradual increase towards the Jubilee Zone from both above and below. Other elements do not exhibit enrichment or depletion towards the Jubilee Zone, but this may be due to the short interval of core studied. Geochemical discrimination plots used to distinguish lithologies provided some insights into the tectonic setting, but were inconclusive due to key elements being below detection limit.

Based on the relationships observed in thin section, gold mineralization could have occurred during a either a single or multiple mineralizing events. Free gold is encapsulated in pyrite and may suggest a single pyrite-gold mineralizing event. An earlier pyrite-gold mineralizing event followed by a later gold-bearing quartz-carbonate fluid would also create the relationships observed in thin section. Lastly, partial assimilation of existing gold-bearing pyrite by a barren quartz-carbonate fluid would remobilize gold into fractures and boundaries of pyrite grains.

Steve is currently working for his MSc at Lakehead University

For more details about this thesis contact Dr. Peter Hollings