UNIVERSITY of ILLINOIS. 
THE 
AMERICAN GEOLOGIST. 
Vol. XIX. APRIL,' 1897. No. 4 
PHYSIOGRAPIC GEOLOGY OF THE PUGET 
SOUND BASIN. 
By James P. Kimball, New York. 
Plate XII. 
I. 
The discovery in Douglass county, Oregon, of unconformity 
between beds of the Shasta-Chieo group and overlying marine 
Tejon strata serves to denote more or less of a physical break 
between the Cretaceous and Eocene on the Pacific border.* 
Extension of the post-Cretaceous or post-Laramie elevation is 
thus indicated, as well as correlation of the Tejon with the 
Eocene. No similar contact unconformity in the Puget Sound 
basin has yet been brought to light. The upheaval, as a rule, 
of the productive lignitic series on the flanks of massive eriip- 
tives in the elevated border of the basin, militates against the 
occurrence of undisturbed unconformities. A single basal 
unconformity of that series, with ancient crystalline schists 
on the Skagit, is noted by Willis, f but with no certainty as 
to whether due to original deposition or to faulting. The 
less elevated and less disturbed marginal developments of 
*J. S. Diller and W. Stanton, Bull. Geol. See. Am., V, 1894, p. 64.3. 
S. F. Emmons, ibid. I, p. 285. Marsh, .\m. Jour. Sci., 4th Ser., II, 
1896, p. 4.39. 
fReport Tenth Census, XV, p. 759. 
