Geology of Graham Island, British Columbia.

CHAPTER. I. INTRODUCTION.

GENERAL STATEMENT.

The southern islands of the Queen Charlotte group are known to contain several deposits of metallic minerals, the value of which has not yet been ascertained except in a preliminary way, and Graham island, the subject of this report, has long been considered to have deposits of coal, lignite, and petroleum. The search for workable bodies of these substances has been carried on at irregular intervals since 1859, and has lately been vigorously renewed.

In the year 1912 a short reconnaissance of part of Graham island was made by Dr. C. H. Clapp, then connected with the Geological Survey, and his report made evident the necessity for further and more detailed study. Accordingly, in 1913, the writer was instructed to make a geological examination of Graham island for the purpose, mainly, of determining the extent, structure, and value of the coal deposits. It was found necessary to continue this examination during two months of 1914, with the result that, in addition to a large amount of detailed work, a reconnaissance was made over the whole island. The results of the two seasons’ exploration and study are con- tained in this report.

FIELD WORK.

In 1913, field work was carried on during the three months from June 22 to September 20. For the work done in that year no maps of sufficient accuracy to serve as a base for geolo- gical mapping were available, with the exception of the Admiralty