454 R. ARNOLD RECONNAISSANCE OF THE OLYMPIC PENINSULA 



northwestern part of the state of Washington. As implied by the name 

 "peninsula/' this body of land is almost completely surrounded by water, 

 the Pacific ocean bounding it on the west, the strait of Juan de Fuca on 

 the north, Admiralty inlet, Hood canal, and other portions of what is 

 popularly known as Puget sound on the east, and Grays harbor and the 

 Chehalis river on the south. It embraces the whole of Clallam and Jef- 

 ferson and portions of Chehalis and Mason counties. Cape Flattery at 

 the northwestern corner and Port Townsend at the northeastern are its 

 most commonly heard place names. 



Topography and physical Features 



THE OLYMPIC MOUNTAINS 



The natural and commercial development of the peninsula is dominated 

 by the Olympic mountains — a rugged group, occupying with their foot- 

 hills the greater part of its territory. The higher mountains* are Alpine, 

 with sharp spires and serrate ridges from 6,000 to 8,000 feet high, cul- 

 minating in mount Olympus, with an altitude of 8,200 feet. They form 

 a circular area 40 miles in diameter in the east central part of the 

 peninsula and are characterized by glacial sculpture, precipitous slopes, 

 and abundance of high barren and prairie land. 



West of the region of high mountains the ridges rise to approximately 

 a plane surface that slopes gently seaward from an elevation of about 4,500 

 or 5,000 feet. This surface truncates the deformed strata of the Solduck 

 region and probably represents a peneplain. 



The following paragraph, descriptive of the Olympic mountains, is an 

 abstract of an article by Chester W. Washburne, now in course of prepara- 

 tion, which will appear in a more extended report on the geology of 

 western Washington. 



The drainage of the region is radial, the radial pattern being very per- 

 fect about the borders of the higher mountains, while within the moun- 

 tains it is less perfect. The streams of the peninsula are arranged much 

 like the spokes of a wheel, of which the region of high mountains is the 

 hub. This pattern could have one of three possible origins: First, the 

 drainage was initiated on a volcanic accumulation about a center ; second, 

 the drainage was initiated on the domed surface of Tertiary strata, which 

 has since been removed by erosion; third, the drainage was initiated on 

 the domed surface of a peneplain. By all of these hypotheses the streams 

 are consequent to some imaginary surface of double curvature. The first 



* See topographic map accompanying Professional paper, U. S. Geologic Survey, no. 7, 

 "Forest conditions in the Olympic reserve, Washington," by A. Dodwell and T. F. Rixon. 



