Landforms of British Columbia 1976 - Department of Geography

Detailed studies made around several placer camps in the Stikine Mountains
indicate that the late Tertiary erosion surface, which was one of moderate relief,
was uplifted prior to the Pleistocene and that a stage of canyon-cutting preceded the
occupation by ice (compare with p. 55).
[References: Kerr, F. A., “ Dease Lake Area,” Geol. SLUT., Canada, Sum.
Rept., 1925, Pt. A; Hanson, G., and McNaughton, D. A., “ Eagle-McDame Area,
Cassiar District,” GeoZ. Surv., Canada, Mem. 194, 1936; Holland, Stuart S.,
“ Placer-gold Deposits, Wheaton (Boulder) Creek,” B.C. Dept. of Mines, Bull. No.
2, 1940; Hedley, M. S., and Holland, Stuart S., “Reconnaissance in the Area of
Turnazain and Upper Kechika Rivers,” B.C. Dept. of Mines, Bull. No. 12, 1941;
Gabrielse, H., “ Geology, Cry Lake,” Geol. Surv., Canada, Map 29-1962; Gabri-
else, H., Souther, J. G., and Roots, E. F., “Geology, Dease Lake,” GeoZ. ,!?urv.,
Canada, Map 21-1962; “Stikine River Area,” Geol. Surv., Canada, Map g-1957.1
[Photographs: B.C. 893: 63; B.C. 954: 23.1
Kechika Ranges
The Kechika Ranges lie along the northeastern side of the Stikine Ranges and
flank the Rocky Mountain Trench from Sifton Pass northwestward for about 110
miles, almost to the Deadwood River. Their eastern boundary is the edge of the
Trench, and their western boundary is drawn along the lineament extending between
Sifton Pass and Deadwood Lake. At their northern end the summit level gradually
diminishes and the mountains merge in the Dease Plateau along an arbitrary line
drawn northeastward from Looncry Lake and along the Deadwood River valley.
The highest peaks in the ranges lie between Moodie Creek and Mount Winston
(7,736 feet), where a hard Lower Cambrian quartzite forms several 7,500-foot
summits. To the north the summits diminish to the Dease Plateau, and to the south
peaks of 6,500 feet extend in northwesterly trending ranges.
The ranges are drained by the Kechika and Turnagain Rivers and their
tributaries. Some tributaries, such as the Frog River and Denetiah and Moodie
Creeks, cut at right angles across the northwesterly trend of the ranges, breaking
them into blocks.
The Kechika Ranges are underlain by folded Precambrian and Paleozoic
sedimentary rocks, dominantly quartzite, limestone, and slate. The high peaks and
ridges have been sharply sculptured by cirque glaciers and the valley profiles are
modified by valley glaciers. Summits and ridges below 6,000 feet are generally
rounded and subdued by erosion of the ice-sheet.
[References: Hedley, M. S., and Holland, Stuart S., “Reconnaissance in the
Area of Turnagain and Upper Kechika Rivers,” B.C. Dept. of Mines, Bull. No. 12,
1941; Gabrielse, H., “ Geology, Kechika,” Geol. Sum., Canada, Map 42-1962.1
Sifton Ranges
The Sifton Ranges lie north of the Finlay River and flank the Rocky Mountain
Trench and Fox River between Ware and Sifton Pass, and wedge out against the
southern tip of the Kechika Ranges. On their western side they are bounded by
the Obo River lineament, which extends northward past Johiah Lake to Airplane
Lake, close to the head of Paddy Creek.
The ranges present a harsh and rugged appearance from the Trench, and from
Mount Balourdet (7,247 feet) to Mount Slocomb there is a succession of 7,500-foot
peaks. The ranges are underlain by metamorphic rocks, comprising quartzite and
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