Landforms of British Columbia 1976 - Department of Geography
Landforms of British Columbia 1976 - Department of Geography
Landforms of British Columbia 1976 - Department of Geography
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LANDFORMS OF BRITISH COLUMBIA<br />
CHAPTER I.-INTRODUCTION<br />
<strong>British</strong> <strong>Columbia</strong> is the westernmost Province <strong>of</strong> Canada. It lies on the Pacihc<br />
Coast <strong>of</strong> North America, stretching from the International Boundary at the 49th<br />
parallel to the Yukon Border at the 6Oth, a distance <strong>of</strong> 790 miles. On the west it<br />
is bounded along half its length by the Pacific Ocean and for the remainder by the<br />
narrow mountainous strip <strong>of</strong> southeastern Alaska. On the east it is bounded by the<br />
Province <strong>of</strong> Alberta along a boundary which follows the watershed <strong>of</strong> the Rocky<br />
Mountains northwestward to the 120th degree <strong>of</strong> longitude and thence northward<br />
along that meridian to latitude 60 degrees north. The area <strong>of</strong> the Province is<br />
366,255 square miles, <strong>of</strong> which 6,976 square miles is covered by lakes. It is second<br />
only to Quebec in size and is 9.5 per cent <strong>of</strong> the area <strong>of</strong> Canada.<br />
There is a great variety <strong>of</strong> topography within thii vast region that extends<br />
through 11 degrees <strong>of</strong> latitude and that extends across the full width <strong>of</strong> the Canadian<br />
Cordillera from the Interior Plains to the Pacific Ocean. Although the Province is<br />
largely mountainous, with land rising from sea-level to a maximum elevation <strong>of</strong><br />
15,300 feet at the summit <strong>of</strong> Mount Fairweather, nevertheless there are extensive<br />
plateaus, large plains and basins, and areas <strong>of</strong> prairie. The contrasts and similarities<br />
that extend over great expanses <strong>of</strong> country and the nature <strong>of</strong> the terrain itself deserve<br />
to be far better known. To grasp this information requires that the Province be<br />
subdivided into units which are topographically alike and that the landforms be<br />
described in such a way that their origins are understood.<br />
This bulletin is concerned with the physical features <strong>of</strong> the Province, such as<br />
plains, plateaus, or mountains, as well as valleys, cirques, or volcanic cones; these<br />
are the landforms which combine to make the topography <strong>of</strong> the Province. Their<br />
description, classification, correlation, and origin comprise the study <strong>of</strong> geomor-<br />
phology,* which is a branch <strong>of</strong> the broad field <strong>of</strong> geology as well as that <strong>of</strong> physi-<br />
ography. Essentially therefore what follows in this bulletin is the geomorphology<br />
<strong>of</strong> <strong>British</strong> <strong>Columbia</strong>.<br />
A geologic time scale and a glossary <strong>of</strong> terms are included in an appendix for<br />
the convenience <strong>of</strong> non-technical readers.<br />
DEVELOPMENT OF LANDFORMS<br />
The topography <strong>of</strong> <strong>British</strong> <strong>Columbia</strong> is constantly changing as the various<br />
features <strong>of</strong> the landscape are attacked by erosion. The landforms seen today rep-<br />
resent only a stage in a continuously repeated cycle <strong>of</strong> events during which the land<br />
surface is lowered and destroyed only to be re-elevated or rebuilt at some later time.<br />
A study <strong>of</strong> landforms makes it possible for the observant eye to piece together<br />
much <strong>of</strong> the recent history <strong>of</strong> the earth by disclosure <strong>of</strong> erosional effects and major<br />
crustal movements. By so doing the course <strong>of</strong> future modifications may be pre-<br />
dicted. Landscapes provide a record <strong>of</strong> the earth’s history that is important to a<br />
geologist or geomorphologist, but the same record may be read by an observant<br />
l The term “ physiography ” was formerly used in this sense, but now it is generally used with a wider<br />
meaning to embrace geomorphology, climatology, and oceanography. The word “ physiographic ” is well estab-<br />
lished in such uses as “ physiographic subdivision ” or “ physiographic history,” which refer only to landforms,<br />
and is used here in preference to “ geomorphologic,” which is synonymous but cumbersome.<br />
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