Geological Papers. 101 



scription of this formation, see Eocene Epoch^ and Geology of the 

 Coal-measures of Washington.* 



Pliocene.— A conglomerate rock was found in a little valley 

 about four miles south of Murphy's Landing, on the Eraser river. 

 A much larger area of the same kind of rock was found on the 

 foot-hills just north of the Suraas mountains. It is undoubtedly 

 much later in age than the Eocene-Miocene of the same region, be- 

 cause in British Colu'mbia it fills a chasm left by the faulting of 

 that formation. As no fossils were found, its age could not be de- 

 termined. Its horizon, however, would seem to place it in the 

 Pliocene. 



Glacial. — The glacial deposits, which exceed 500 feet in thick- 

 ness, are the surface rock of the entire region from the foot- 

 hills to Georgian Bay, except where they are covered with recent 

 deposits. They were deposited in the then Georgian Bay from the 

 Mt. Baker and British Columbia glaciers. At the culmination 

 of glacial times these two glaciers seem to have been one continu- 

 ous ice-sheet thousands of feet thick which extended south prob- 

 ably to the Olympic mountains and westward to the Pacific;* but? 

 as the epoch began to wane, they became separated and acted in- 

 dependently of each other. The Mt. Baker or Nooksack glacier 

 then seems to have followed about the course of the Nooksack river 

 to Lynden, and would have continued its course in a northwestern 

 direction if it had not encountered the foot of the northern ice- 

 sheet. This turned it in its course from a northwest to a southwest 

 direction, causing a push-medial moraine, now a ridge, to be formed 

 where the two glaciers came in contact, and a dump-terminal mo- 

 raine from Blaine south to the portage along the Georgian Bay 

 coast. The Eraser glacier at this time was stopped in its southern 

 advance and turned westward by the granite trap and Eocene high- 

 lands in British Columbia, and further deflected westward by the 

 Mt. Baker glacier. Its final dump moraine was probably in 

 Georgian Bay, to the west of the present coast-line. On their final 

 retreat from the region these two glaciers left elevated areas where 

 their push-medial, terminal and lateral moraines had been ; and 

 estuaries or sounds between these and the foot-hills, all the country 

 but the morainic strips being at or below sea-level. These strips 

 are typically glacial, and present practically all the phenomena pe- 

 culiar to a glacial region. 



3. Landes, Washington Geological Survey, vol. I, part I, p. 29. 



4. Loc. cit., part IV, p. 43. 



* This glacier passed over Orchis island, which is 1800 feet in height, the glacier stripping 

 the island of practically all its soil. 



