Overview of Results from the Greenstone ... - Geology Ontario

The Currie (Tillex) showing occurs in the sediments and felsic tuffs of the upper Tisdale assemblage,
and is within the same stratigraphic sequence that hosts the Cross Lake deposit (Ontario Geological
Survey 2004b; Vaillancourt 2001). The mineralization described by Expatriate Resources, and described
and observed in drill core from Kinross Gold Corporation and core in the Kirkland Lake Drill Core
Library occurred as small stringers, and along bedding and foliation planes. The mineralized zones are
commonly schistose, and numerous bedding parallel faults and sheared zones are observed in drill core.
The mineralization in the Marker Horizon (Corfu and Noble 1992) of the upper Tisdale assemblage
in Currie Township appears to be integrally associated with the sediments and felsic tuffs. A unit of
particular interest within this assemblage corresponds to a magnetic high on the magnetic map and can be
traced with few breaks across the entire township (Ontario Geological Survey 2004a). A second unit with
a high magnetic signature occurs 200 to 300 m south of the first. The generally east-west orientation of
these magnetic highs is subparallel to the interpreted upper Tisdale–lower Blake River assemblage
boundary. These magnetic units may be stratigraphic and used as “marker units” within the Marker
Horizon of the upper Tisdale assemblage.
NICKEL-COPPER-PLATINUM GROUP ELEMENT MINERALIZATION
SUBPROJECT
This subproject is an affiliated OGS project that has been designed to complement the Discover Abitibi
Greenstone Architecture Project (base metal and gold subprojects) by focusing on nickel-copper-platinum
group element (PGE) mineralization in the Abitibi greenstone belt, but more specifically in the Shaw
Dome area in the vicinity of known komatiite-associated deposits. This project represents an in-kind OGS
contribution, which is both part of the Ontario Geological Survey core program and part of an ongoing
PhD study by M.G. Houlé based at Laurentian University (LU) and the University of Ottawa (UO) on the
physical volcanology and metallogenesis of komatiites in the Abitibi greenstone belt. Because of the
nature of this in-kind OGS–LU–UO contribution, the Ni-Cu-(PGE) subproject section has progressed
along a different time frame, so this section represents a summary rather than a complete assessment of
the exploration potential of komatiite-associated deposits in the Abitibi greenstone belt.
This part of the Discover Abitibi Greenstone Architecture subproject has focussed on the Shaw
Dome for several reasons: 1) it is one of the areas in the Abitibi greenstone belt that contains known
occurrences of komatiite-associated deposits, and 2) the Shaw Dome area provides an opportunity to
examine the physical volcanology of komatiitic rocks at several scales (i.e., outcrop, property, and
regional).
The goals of this subproject are three-fold:
1. to evaluate the subvolcanic–volcanic architecture of the ultramafic rocks in the Shaw Dome
2. to evaluate the Ni-Cu-(PGE) mineral potential of the komatiitic rocks in the Shaw Dome
3. to extend what we have learned about the physical volcanology and metallogenesis of komatiitic
rocks in the Shaw Dome to the scale of the Abitibi greenstone belt
A multi-scale, integrated approach is critical in constraining the komatiite volcanic facies to aid in
the interpretation of the volcanic architecture of komatiite flow fields and to assess the mineral potential
for komatiite-associated Ni-Cu-(PGE) deposits.
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