The areas shaded in magenta have been surveyed on the ground and found to contain bedrock outcrops affected by subglacial brecciation.  While bedrock outcrops are abundant in the indicated zones, the majority of the marked area is either forested, beneath lakes or covered by glacial till with low vegetation and peat.  Most exposed bedrock in the indicated areas has been severely affected by a combination of subglacial thermal brecciation (subglacial frost heave, subglacial frost wedging) or mechanical brecciation imparted by the action of cold-based glaciers.

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The magenta-shaded areas extend over approximately 220 square kilometers.  Of this area, 50 square kilometers lies in the southwest (Isthmus) zone and 170 square kilometers lies in the northeast (Heart's Content Barrens) zone.

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