Rock Textures at Cap Rouge

Canada’s Atlantic Maritime Provinces have a fascinating geological history. Nova Scotia has an exquisite array of rock types and formations. The difficulty is gaining access to them without going off-road and hiking into the wilderness. Fortunately, along the Cabot Trail in the Cape Breton Highlands National Park there are many signed trail heads and information areas that bring an understanding of the wonderful surrounding landscape to the less adventurous or less able visitor. One of these roadside areas at Cap Rouge explains how the view shows the three basic types of rock (igneous, sedimentary, and metamorphic) in the one vista – provided it is not completely obscured by heavy rain and dense cloud cover as it was on the day I visited.

The wall bearing the information boards is, however, constructed from intensely metamorphosed rock from the adjacent highlands of French Mountain; and large boulders bordering the parking area (unfortunately unlabelled) provide further examples of the metasedimentary rocks from the Ordovician to Silurian rocks of the Aspy Terrane, and the Neo-Proterozoic to Ordovician grantitic pluton rocks of the Bras D’Or Terrane of the surrounding region . [A terrane “is a fault-bounded fragment of continental crust broken from one tectonic plate and later joined to another during continental collision, recognized as such by its distinctive rock units and separate sedimentary, igneous and metamorphic history as compared to adjacent parts of an orogen” (Hickman Hild and Barr , 2015). An orogen is the result of mountain building processes as preserved in the rock record].

REFERENCES

Hickman Hild, M. and Barr, S. M. (2015) Geology of Nova Scotia, A Field Guide, Touring through time at 48 scenic sites, Boulder Publications, Portugal Coce-St. Philip’s, Newfoundland and Labrador. ISBN 978-1-927099-43-8.

Donohoe, H. V. Jnr, White, C. E., Raeside, R. P. and Fisher, B. E, (2005) Geological Highway Map of Nova Scotia, Third Edition. Atlantic Geoscience Society Special Publication #1.