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The Coast Range does not exist in Canada

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Whistler Naturalists

The Coast Range lies in British Columbia and the Yukon? No dice, the Coast Range is a series of low hills bordering the Pacific Ocean in southern Washington, all of Oregon and northern California. Their location was defined by American physiographers in the early decades of the 20 th century. But the Coast Mountains lie within British Columbia and finally fade out in the Yukon Territory just west of Whitehorse. Our "mountains" were so defined by the eminent Canadian geologist of the 19 th century, Dr. George Mercer Dawson, and have been re-affirmed to that nomenclature by the Geographic Board of Canada on several occasions in the early 20 th century, as well as by three very high-powered treatises on British Columbia and Yukon landforms compiled since then.

Now, let us look at hierarchy of the classification of the various features of our western landscape — a science known as "physiography" and who are these eminent authors who defined it.

The principles of the classification of the landforms of our landscape were first set out by Dr. H.S. Bostock (1948) in his landmark publication: "Physiography of the Canadian Cordillera, with special reference to the area north of the fifty-fifth parallel" (Geological Survey of Canada, Memoir 247). "The Canadian Cordillera forms part of the great system of mountains that border the Pacific in North and South America," forming the watershed between the Pacific and Atlantic Oceans, and the Arctic Ocean as well in Canada and Alaska. Within Canada and Alaska the Cordillera is subdivided into three systems: Eastern, underlain by mainly sedimentary rocks and bounded by the Rocky Mountain Trench on its west side; Interior, of mixed volcanic, sedimentary, and metamorphic rocks, intruded here and there by granitic rocks (Columbia Mountains in southern B.C., and Omineca Mountains to the north); and Western, of predominantly granitic rocks, with overlying remnants here and there of metamorphosed sedimentary and volcanic rocks (that’s us).

Within the Western System there are three great chains defined as Mountains (the next level down in hierarchical order): the Cascade Mountains to the south and east of the Fraser River, which continue southward through Washington into Oregon; the Coast Mountains which run from the Fraser northward to the Takhini Valley in the Yukon; and the Insular Mountains of Vancouver and Queen Charlotte Islands. A major feature defined as the Coastal Trough separates the Coast Mountains to the east from the Insular Mountains on the west, and the latter continue northward through to the Saint Elias Mountains of southeast Alaska, southwest Yukon.

Now turning to the sub-division of "mountains", the descending hierarchical levels are Ranges , then an individual Range within them, and finally an informally named "group" which refers to a local cluster of peaks. The sub-division of the Coast Mountains into Ranges was initially set out by Dr. Bostock: Pacific Ranges to as far north as the Nass River Valley (north of Prince Rupert), and north of the Nass the Boundary Ranges, which lie along the boundary to southeast Alaska and then fade out in the Yukon.

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