486 R. ARNOLD— RECONNAISSANCE OF THE OLYMPIC PENINSULA 



glomerate are numerous well preserved Miocene fossils, similar to those 

 found at the mouth of the Sekiu river (see list). The maximum section 

 exposed in the Clallam Bay-Hoko Kiver Pliocene area is only 240 feet 

 thick, but this probably represents only a part of the formation. 



Pleistocene — General character of the deposits. — The Pleistocene de- 

 posits of the region under discussion consist of till, clay, sand, and gravel, 

 mostly incoherent but sometimes locally firmly cemented by iron oxide 

 (see plate 58, figure 2). They extend from Port Townsend along the 

 strait to the region about Gettysburg and from Portage head to a short 

 distance south of point Greenville, on the Pacific Ocean side. In the 

 vicinity of Port Angeles and eastward to Port Townsend the Pleistocene 

 is between 200 and 300 feet thick ; its lowest member till, the rest of the 



Figure 4. — Section of small Promontory on Coast 2 Miles West of Clallam. 

 Showing unconformity between the Miocene and Pliocene. 



formation roughly stratified sand and gravel. This till is probably the 

 equivalent of Willis's Admiralty till of the Puget Sound country. The 

 top of the till, which is largely a stiff blue clay, is often marked by springs. 

 In the vicinity of Freshwater bay these springs are large and exceedingly 

 numerous, and are said to have been used by the early navigators in stock- 

 ing their ships with water ; hence the name of the bay. 



The maximum development of the Pleistocene on the western side of 

 the peninsula is in the region about Yellow banks, 6 miles south of the 

 mouth of the Ozette river, where the deposits of sand and gravel attain a 

 thickness of over 125 feet. The marine origin of at least a part of the 

 Pleistocene deposits along this part of the coast is attested by marine 



