GENERAL GEOLOGIC STRUCTURE 467 



fossils, which are found in fine stratified sands 35 feet above tide level 

 near Point of the Arches. 



Gold in the Pleistocene gravels.* — In certain localities the Pleistocene 

 deposits which constitute or cap the bluffs from near Portage head south 

 to Yellow banks carry small amounts of gold, platinum, and iridosmine. 

 By a process of wave action these metals have been concentrated on or near 

 the bedrock at the base of the bluffs, sometimes in quantities of economic 

 importance. The gold and other precious metals in these beach deposits 

 are always associated with magnetite and garnet sand, although the places 

 richest in the "indicators" are often barren of the gold in paying quan- 

 tities. 



Mining has been carried on in the region since 1894, and during this 

 period at least $15,000 has been taken from the Shishi Beach placers be- 

 tween Portage head and Point of the Arches alone. Besides the Shishi 

 Beach workings, there are paying claims being worked intermittently 2 

 miles north of the mouth of the Ozette river, and at Yellow Banks, 6 

 miles south of the mouth of the same river. The mining is carried on 

 principally by the sluice-box method, although where the water supply is 

 limited, as at the locality 2 miles north of the Ozette, rockers are used. 



GEOLOGIC STRUCTURE IN GENERAL 



As indicated by the exposures along the coast, the structural lines in 

 the region from Port Angeles to Gettysburg average approximately parallel 

 to the trend of the Olympics, north 70 degrees west, south 70 degrees east ; 

 those in the Gettysburg-Clallam Bay territory almost perpendicular to 

 this, or a little east of north, and those in the Clallam Bay-Cape Flattery 

 stretch north 30 degrees west, south 30 degrees east, or again parallel 

 with the ridges which extend along the coast in this region. A syncline, 

 with its southern limb resting against the sandstones south of lake Cres- 

 cent and its northern one truncated by the waters of the strait of Fuca, 

 is the major structural feature of the Port Crescent-Gettysburg region. 

 From Gettysburg westward to the mouth of the Pysht river the structural 

 features are not pronounced, the rocks in general, however, having a west- 

 ward dip. A rather broad syncline, with its axis extending in a northeast- 

 erly-southwesterly direction, occupies most of the territory between the 

 Pysht river and Clallam bay. This syncline is complicated in its south- 

 eastern portion by sharp local folding and some faulting. The region 

 between Clallam bay and cape Flattery is formed by a great northeast- 



* Bulletin no. 260, U. S. Geological Survey, 1905, pp. 154-157. 

 XLI — Bull. Geol. Soc. Am., Vol. 17, 1905 



