Geological setting of gold deposits in the Porcupine Gold Camp, Timmins, Ontario

The Porcupine Gold Camp (PGC) is situated in a late Archean volcanic complex north of the Destor Porcupine fault at Timmins, Ontario.;Deformation prior to deposition of Timiskaming sedimentary rocks resulted in east-west striking, periclinal, north-verging folds lacking axial planar fabrics that are the dominant control on the distribution of lithostratigraphic units in the Timmins area.;Epizonal quartz-feldspar porphyritic felsic intrusions ("porphyries") and associated phreato-magmatic breccias were emplaced between 2688+/;Intrusion of 2673+6/;Geometries of intrusions and of primary and hydrothermal features were modified during post-mineralisation deformation. Early folds were modified and refolded about southeast trending fold axes. Flattened hydrothemal stockworks define LS fabrics in penetratively deformed rocks. High strain zones, characterised by strong closely spaced to continuous cleavage, developed preferentially in incompetent lithologies and sericitic alteration zones. They lack lateral continuity and consistent kinematic indicators and are merely zones of intense shortening and elongation rather than ductile shearing. The Hollinger and Moneta faults are brittle, gouge-filled faults that post-date penetrative deformation and offset post-orogenic early Proterozoic diabase dykes. (Abstract shortened by UMI.).