9 
Gabbros of East Sooke and Kocky Point. 
By H. C. Cooke. 
INTRODUCTION. 
Two plutonic masses of general gabbroid composition 
occur on the southwestern coast of Vancouver island, about 15 
miles southwest of the city of Victoria. The larger underlies the 
greater pa# of East Sooke peninsula and is elliptical in outline. 
Its major axis is about 5 miles in length and its minor axis about 
2| miles. It is of economic interest as it forms the country rock 
of the East Sooke copper deposits, and of scientific interest as it 
affords an excellent example of the course of differentiation of a 
gabbro magma. The smaller, or Rocky Point mass, lies about 
3 miles to the east ; it contains no ore deposits, and a much larger 
proportion of if is beneath sea-level, but in the variety and char- 
acter of its rocks it is identical with the East Sooke body. 
A number of other masses of the same gabbro are found through- 
out the Sooke map-area, and in 1912 the generic name 
of “ Sooke gabbro M was applied by Clapp 1 to the whole 
group, Clapp at that time also recognized and reported the pros- 
pective value of the copper deposits in East Sooke peninsula, 
and recommended a detailed examination of the district to 
secure more definite information as to its economic possibilities. 
Accordingly, early in the summer of 1913 the peninsula was 
mapped topographically by F. S. Falconer, of the Geological 
Survey staff, on a scale of 2,000 feet to 1 inch, with a 20-foot 
contour interval. Later in the season the writer and his assist-# 
ants, V. Dolmage and A. McLeod, spent four weeks examining 
the geology of the two areas. 
i Geol. Surv., Can., Mem. 13, 1912, p. 113. 
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