PAPERS READ BEFORE PACIFIC COAST SECTION 131 



lying beds indicates to a certain extent the depth of submergence and the 

 distance to which the shoreline may have retreated. Contacts containing bor- 

 ing shells, moreover, show the location of the headlands and open coast along 

 the ancient sea margin. 



DISCUSSION OF THE JURASSIC AGE OF THE SLATES AT SLATE SPRINGS, 

 MONTEREY COUNTY, CALIFORNIA 



BY CHARLES H. DAVIS 



(Abstract) 



The slates of the Slate Springs beds dip unconformably under the basal 

 Knoxville, as described by Dr. H. W. Fairbanks. The Lower Knoxville is 

 placed by some geologists in the Upper Jurassic. 



The species from Slate Springs are very similar and in five instances out 

 of eight are practically identical with described Jurassic forms. None of the 

 species are unlike Jurassic forms. Six of the eight species listed from Slate 

 Springs are identical, or nearly identical, with species described from the 

 Queen Charlotte Islands, British Columbia. The Queen Charlotte Islands 

 beds have been definitely correlated by Stanton with the Enockin formation 

 of Alaska which he calls Upper Middle Jurassic. The above considerations 

 appear to place the Slate Springs (Franciscan?) beds in an age not higher 

 than the lower Upper Jurassic. 



PRELIMINARY REPORT ON THE TERTIARY PALEONTOLOGY AND 

 STRATIGRAPHY OF SOUTHWESTERN WASHINGTON 



BY CHARLES E. WEAVER 



(Abstract) 



Marine strata of Eocene, Miocene, and perhaps Pliocene age, with a total 

 maximum thickness of about 30,000 feet, are found in southwestern Washing- 

 ton. The sediments along the north coast of Washington form only a thin 

 fringe from Cape Flattery eastward, but are found west of the Cascade Moun- 

 tains from the Columbia River to Cape Flattery. 



The Eocene is found west of the Cascades and in the Puget Sound Basin 

 from Seattle to near the Chehalis River. There were great fluctuations of 

 land and sea and outpourings of basaltic lavas during the Eocene. West of 

 the Cascades the lavas are interbedded with marine sediments, and the later 

 fauna is typically Tejon, while the older fauna's position is not yet de- 

 termined. Toward the east brackish-water beds, constituting the Paget group 

 of Willis, prevail and are probably the equivalent of the marine Tejon farther 

 west. The Roslyn of central Washington is probably equivalent to the marine 

 Tejon. The lavas are not found in the Olympic Peninsula. The coal of 

 Washington is almost entirely confined to the TeJOD horizon, [gneous activity 

 ceased entirely at the close of the Tejon. 



There is a distinct unconformity between the Tejon and the overlying beds 

 carrying a fauna akin to that of DalPs Astoria beds. Above this unconformity 

 are 10,000 feet of beds, with two faunas, that of the upper beds being quite 

 distinct from that of the lower. The Upper Miocene is similar to the San 

 Pablo. 



