THE CHARACTER OF THE STRATIFICATION OF THE 



SEDIMENTS IN THE RECENT DELTA OF FRASER 



RIVER, BRITISH COLUMBIA, CANADA^ 



W. A. JOHNSTON 



Geological Survey of Canada, Ottawa, Canada 



OUTLINE 



Introduction 



Fraser River and Its Recent Delta 



Pitt Lake Delta 



Character of Stratification of the Sediments 



Summary of Conclusions 



INTRODUCTION 



During the course of an investigation, carried on during parts 

 of 1919 and 1920 by the Geological Survey of Canada in co-operation 

 with the Department of Public Works, of the characteristics of 

 Fraser River, British Columbia, an opportunity was afforded of 

 studying the character and mode of origin of the stratification of 

 the sediments forming the Recent delta of the Fraser. Bottom 

 samples were obtained by means of a bottom-sampling machine 

 which furnished core samples (i) from the sea-bottom deposits in 

 the Strait of Georgia, and (2) from the fresh-water deposits in 

 Pitt Lake, a tidal lake tributary to the Fraser. The object of this 

 paper is to describe the character and mode of origin of the stratifica- 

 tion of the Recent delta deposits of the Fraser River, and to contrast 

 the character of the stratification of the sediments being formed in 

 fresh water with that of the sediments being formed in salt water. 



The writer is indebted to Dr. W. Bell Dawson, superintendent 

 of the Tidal and Current Survey, Department of the Naval Service, 

 Canada, for information regarding the tides and tidal currents in 

 Fraser River and in Pitt Lake, and to Mr. C. C. Worsfold, district 

 engineer, Department of Public Works, Canada, for information 

 regarding the tides and freshets in Fraser River. 



^ Published by permission of the Director of the Geological Survey, Canada. 



IMS 



