Randy David Farmer HBSc thesis abstract

Thesis Title: 
Structure and Stratigraphy of an Archean Succession, Gorham Township, Thunder Bay, Ontario
Randy David
Farmer
HBSc
1980

The area is underlain by Archean sedimentary and volcanic successions and forms part of the Shebandowan-Wawa volcano-plutonic belt.  In the area the rocks have been subjected to three distinctive episodes of deformation.  Two phases of folding were followed by development of kink bands and a crenulation cleavage.  The first folding consisted of tight, recumbent folds with east-west trending axial traces.  The second phase of folding consisted of smaller, more open folds with northeast trending, steeply dipping axial traces.  The later kink bands formed only in rocks possessing a strong planar anisotropy.

The most abundant rock type present in the study area are greywackes.  These greywackes exhibit features characteristic of turbidites.  Framework minerals of these rocks consist primarily of felsic volcanic rock fragments.

The presence of coarse pyroclastic rocks interbedded with these sedimentary rocks is the result of contribution of detritus from multiple sources.