|The Olympic Mountains from Vancouver Island across the Strait of Juan de Fuca|
|The Belts of British Columbia and Alberta, Canada. Source: Wikipedia and Black Tusk|
And finally, there are the terranes. The age of a mountain range bears little relationship to the age of the rocks exposed in the mountain range. There are youthful mountain ranges around the world that have existed for no more than 3-4 million years, but contain rocks that formed billions of years ago. The Black Mountains of Death Valley National Park in California are an excellent example. The tectonic belts of British Columbia contain rocks that not only are not the same age as the physical mountains, but which formed in an entirely different part of the world! A terrane (or tectonostratigraphic terrane) can be defined as a section of the Earth's crust that has been transported by tectonic processes from its place of origin. Terranes are usually bounded by faults. Some of the terranes in western Canada have traveled thousands of miles, while others originated fairly close to the Pacific Coast.
The Insular Belt is the tectonically active edge of the continent, characterized by far-traveled exotic terranes exposed on Vancouver and other coastal islands. We explored parts of Vancouver Island on the second day of our journey.
|The granitic dome Stawamus Chief from Shannon Falls Provincial Park|
|Part of the Chilcotin Mountains near Lillooet, British Columbia|
|Eroded plateaus in the vicinity of Kamloops, B.C. Photo by Mrs. Geotripper|
|The Monashee Mountains from Mount Revelstoke.|
|Emerald Lake in Yoho National Park|
|Peyto Lake in Banff National Park|
Our journey begins in the next post as we gathered in Seattle to start the class.