No. 7.] 



Q. M. DAWSON — SURFACE GEOLOGY. 



399 



w^^^^^^BS^Ma^wum^ . 



Diagrams illustrating stages in the production of the Inlets and Passages 

 of Puget Sound. 



No. 1. Eroded (perhaps glacier-planed) surface of the Tertiary rocks 

 (6) covered uniformly with drift material (a) at the close 

 of the glacial epoch. 



No. 2. Wide and deep valleys cut into the drift deposits by streams. 

 Land standing at a greater, elevation than at present. 



No. 3. Valleys filled by the sea owing to subsidence. Shore cliffs 

 and recent submarine deposits in course of formation. 



