692 



INDEX TO THE STRATIGRAPHY OF NORTH AMERICA. 



M 9-10. VANCOUVER ISLAND. 



The Cretaceous of Vancouver Island forms three areas — the Nanaimo, Comox, 

 and Quatsino, named from southeast to northwest. There are local differences of 

 stratigraphy among the basins, but in general the terrane closely resembles that of 

 Queen Charlotte Island, except that the two lower formations of that island are 

 lacking on Vancouver. Dawson ^^^^ states : 



In the northern part of Vancouver Island the Cretaceous which still remains appears to 

 consist of outliers of a distinct and older basin and may probably be regarded as having been 

 originally continuous with that developed in the Queen Charlotte Islands. The Cretaceous 

 rocks of Quatsino Sound have so far afforded the best sections, and ki these we appear to find 

 the three higher members of the Cretaceous section of the Queen Charlotte Islands, as it exists 

 in the vicinity of Skidegate Inlet. * * * In comparing these with the corresponding rocks 

 of the Queen Charlotte Islands it is probable that the thickness of the Quatsino b^ds is some- 

 what less and that the conditions met with in the lower or coal-bearing portion of the series 

 are more distinctly littoral at Quatsino, sandstones and conglomeratic layers being relatively 

 more important. The Cretaceous rocks which extend along the northeast shore of Vancouver 

 Island, from Port McNeill to Beaver Harbor, may in part represent the lowest or coal-bearing 

 portion of the Quatsino section. A few fossil plants obtained from Beaver Harbor are Middle 

 Cretaceous and possibly referable to a horizon near that of the lowest beds at Quatsino, but 

 are regarded by Sir William Dawson as distinctly newer than these, though possibly older than 

 much larger collections since made at Port McNeill, which have not yet been worked up in detail, 

 the Nanaimo and Comox Cretaceous floras. It is thus evident that we have not merely a single 

 horizon to deal with along this part of the northeast coast. No trace of the lower subdivisions 

 represented at Skidegate (D and E) has yet been found on Vancouver Island. 



The relations of the Cretaceous rocks of the Queen Charlotte Islands and those of the 

 northern part of Vancouver Island, as now understood, may be expressed as below, in tabular 

 form: 



In the course of the examination of the Cretaceous rocks of the northern part of Vancouver 

 Island, it has been found that these rest unconformably on a rough and irregular denudation 

 surface of the older rocks. * * * Owing to this circumstance the higher Cretaceous beds 

 successively overlap the older rocks, and as the areas of these beds which have escaped subse- 

 quent denudation are probably to a great extent those which have filled the deeper portions of 

 the hollows, it follows that the actual outcroppiag edges of the beds rarely give a complete 

 section of the entire thickness of the formation. 



In 1873 Richardson "^ made a report on the Nanaimo ana Comox fields, which 

 contains numerous detailed sections of the Cretaceous strata. Dawson ^'^ sum- 

 marizes the facts as follows : 



The rocks accompanying the coals are sandstones, conglomerates, and shales, being largely 

 of the character of littoral formations but also containing, particularly in the shaly members of 



