Landforms of British Columbia 1976 - Department of Geography

Field work by members of the Geological Survey of Canada in all parts of the
Province provided detailed information which was collected by H. S. Bostock and
elaborated by him through the study of numerous aerial photographs; it was pub-
lished as “ Physiography of the Canadian Cordillera, with Special Reference to the
Area North of the Fifty-fifth Parallel ” in Geological Survey of Canada Memoir
247. This work, since its publication in 1948, has served as the standard reference
for the physiography of northern British Columbia and the Yukon.
SOURCES 0~ INFORMATION
The present report follows the schematic framework of classification and
nomenclature established by Bostock in Memoir 247. Additional details of geology
and physiography over a large part of the Province are available in the published
geological maps and reports of the Geological Survey of Canada.
Basic topographic information is available from published contoured topo-
graphic maps. The National Topographic System Maps, at 4 miles to the inch
and with a contour interval of 500 feet, now cover a large percentage of the
Province, with only a few sheets not available. More detailed topography is avail-
able in some parts at 1 and 2 miles to the inch with lOO-foot contours.
An extremely valuable contribution is the Relief Map of British Columbia,
Map 1 JR, issued in 1960 by the Department of Lands and Forests, Victoria, at 30
miles to the inch. The Department of Lands, Forests, and Water Resources has
also published six landform maps of British Columbia-Sheets lo, lo, lo, lo, lo,
IK-covering the entire Province at a scale of 10 miles to the inch.
Vertical aerial photographs of most of the Province are available in the Air
Photo Library of the Department of Lands, Forests, and Water Resources, Victoria.
This report has benefited greatly from study of many thousands of oblique aerial
photographs taken by trimetrogon camera at 16,000 to 18,000 feet altitude along
several hundred flight lines throughout most of the Province. These photographs
are also in the Air Photo Library of the Department of Lands, Forests, and Water
Resources, Victoria. Prints are available for loan or may be purchased. They
include photographs of great interest and great excellence, and a large number of
them have been used to illustrate this report.
The writer wishes to acknowledge the very great help and co-operation of
H. S. Bostock, of the Geological Survey of Canada, Ottawa, during the preparation
of this report. In addition, benefit has been derived from critical comments and
suggestions by R. G. Campbell, Jon Muller, and J. Souther, of the Geological Sur-
vey of Canada, and by W. H. Mathews, of the University of British Columbia.
SELECTION OF BOUNDARIES
When confronted with the problem of drawing a map showing the boundaries
of the various subdivisions of the Cordillera, it is necessary to select somewhat
arbitrarily certain types of features as the boundaries between units. On the
accompanying map and in descriptions in Chapter II, boundaries separating units
are drawn in the majority of instances along the following features:-
(1) Major or minor physical features such as the Kootenay Lake-Duncan
River-Beaver River valley, Fraser River valley between Chilliwack and
Lytton, Arrow Lake-Columbia River valley, and Chukachida River-
Thudaka Creek-Finlay River valley.
(2) Geologic structural lines such as the Rocky Mountain Trench, Pinchi
Lake fault zone, Louis Creek fault zone, and Pelly Creek lineament.
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