John Robert Dubyk HBSc thesis abstract

Thesis Title: 
The Structure and Stratigraphy of an Archean Volcanic and Sedimentary Succession in the Kaministiquia Area
John Robert
Dubyk
HBSc
1982

The area is underlain by Archean volcanic and sedimentary rocks of the Superior structural province and forms part of the Shebandowan-Wawa volcanic-plutonic belt.

In the study area, a volcanic succession with intercalated sedimentary rocks is exposed.  Volcanism is of the bimodal, basalt-rhyolite type.  Pyroclastic rocks from part of the volcanic pile and occur together with rudaceous sedimentary strata.  One complete and two incomplete cycles of mafic to felsic volcanism, followed by sedimentation, are observed in the area.  A sulfide (pyrite-chert) and an oxide (banded magnetite-jasper) facies iron formation outcrops within the area.

At least one deformational event is recorded by the steeply dipping bedding planes of sedimentary units.  A variably developed cleavage is present in most rocks.  Cleavage-bedding relationship and local younging data suggest a synclincal axis to the north of the area.  The rocks have been metamorphosed to greenschist and lower epidote-amphibilite facies conditions.

A small hornblende gabbro intrusive is situated near the centre of the area.