NORTHERN PART OF THE PINCHI LAKE
MERCURY BELT, BRITISH COLUMBIA

INTRODUCTION

The’ Pinchi Lake mercury belt is in central British Columbia.
It isat least 130 miles long, extending northwest from Jumping Lake,
15 miles southeast of Fort St. James, to Omineca River. During the
field season of 1937 cinnabar was discovered by J. Gs Gray” in Permian

ieeolasurvas) Ganeoes peer 58-10..

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limestone on the north shore of Pinchi Lake where the main showings of
the Pinchi Lake mercury mine were later developed. The production of
mercury,.from.this deposit is far in excess of Canadian requirements, and
Canada is able to supply the United Kingdom and the United States with
part of their needs.

Since 1940 other occurrences of cinnabar have been found north-
west and southeast of Pinchi Lake. During 1941 and 1943 the writer made
a geological investigation of the known cinnabar deposits and of the belt
in which they occur. The present report deals with the northern 45 miles
of the belt; an ‘earlier report dealing with the southern part was issued
in 1942.

2 esol, Surv.,- Canada, Paper: 42-11.

The northern part of the mercury belt is accessible by truck
road, $0 miles long, from Takla Landing. Motor launches tow 20~ton
scows to Takla Landing from Fort St. James at the foot of Stuart Lake, .
a distance of 110 miles. Fort St. James, in turn, is reached by a good

motor road, 41 miles long, from Vanderhoof on the Canadian National Rail-

way. The minimum freight charge from the railway into the district is
3 cents a pound.

The writer is indebted to officials of Consolidated: Mining
and Smelting Company and Bralorne Mines, Limited, for their generous
co-operation, and to the prospectors of the district for many courtesies
extended. In the field work he was ably’ assisted: by Messrs. Ge We Sin~
clair, Ee Fe Roots, and K. A. Matheson.

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PHYSICAL FEATURES in

The area explored has an average relief of 2,500 to 3,000 feet.
Above timber line, at an elevation of about 5,000 feet, much of ae bed-=
rock is exposed, but elsewhere rock outcrops occupy less than 5 per cent
of the map-area. Drift deposits, chiefly of glacial origin, mantle the
timbered slopes and spread out widely and deeply over most of the low-
land areas. Many of the creeks cut through drift to bedrock.

GENERAL GEOLOGY
The Pinchi Lake fault zone bisects the area from northwest to

southeast. A thick succession of steeply folded Permian limestones and
other interbedded sedimentary rocks outcrops on the southwest side of the