460 R. ARNOLD RECONNAISSANCE OF THE OLYMPIC PENINSULA 



coarse gray sandstone, with occasional zones of black shale and rarely a 

 little conglomerate. The thickness of the formation is probably over 

 5,000 feet, although, owing to its complex structure, this is only a very 

 rough approximation. The series is characterized by calcite veins, which 

 are abundant in nearly all of the exposures. The shales carry some lignite 

 at two or three places, at one locality in particular the coal being used 

 locally for domestic purposes. Indications of oil are also very noticeable 

 in a soft gray sandstone, which may belong to this series, outcropping in 

 a canyon about a mile north of Point of the Arches. This oil has a 

 similar odor to that found in the serpentine and conglomerate a mile or 

 so to the north and may be derived from the shales associated with the 

 sandstone. Indications of oil are also said to have been discovered in the 



N IC C W 



.•y'SSl" *' S »~ BASALT 



o ioo 









£1 



>^Vbasalt - 



-PLEISTOCENE 

 Sea.Le-v-e.1 



100 



BASALT 

 300 *«o re 



JFF 













Figure 3. — Section along eastern End of Crescent Bay. 



Showing the relations of the Eocene basalt, fossiliferous Eocene basalt tuff, and the 

 fossiliferous marine Pleistocene. 



sandstones and shales south of the mouth of the Quillayute river and at 

 one or two other localities between the Quillayute and cape Elizabeth. 



Eocene: Crescent formation. — The oldest formation of definitely 

 known age on the Olympic peninsula is a 1,200-foot series of black basalt 

 and greenish basalt tuffs and tuffaceous sands found in the vicinity of 

 Port Crescent and here designated the Crescent formation. It comprises 

 the region immediately west of Crescent bay and a prominent ridge ex- 

 tending eastward from the latter to Freshwater bay. Venericardia 

 planicosta Lamarck, Turritella uvasana Conrad, and other characteristic 

 fossils found in the tuff indicate the Eocene age of the series and its 

 general contemporaneity with the Tejon of California. 



The basalt occurs in two thick sheets, an upper and a lower, each of 

 which may represent several surface flows. Between the two basalt sheets 

 and intimately associated with the top of the lower is a series of roughly 

 bedded fossiliferous tuffs. Figure 3 illustrates the relations of the differ- 



