dilleb.] STAGES OF DEVELOPMENT. 13 
10. Post-Hay Fork uplift.. — Succeeding the Hay Fork stage came an 
uplift affecting the whole coast. In northern California the uplift 
was in the neighborhood of 1,500 feet, raising the land at least GOO 
feet above the present level, and forcing the coast westward to the 
border of the continent adjoining the deep sea. During this upward 
movement there was considerable displacement, for the fine sediments 
of the Hay Fork stage are in places somewhat tilted. 
11. Continental border stage. — High altitude and rapid erosion pre- 
vailed during the continental border stage. The revived rivers swept 
away much of the unconsolidated material which had filled the old 
valleys and cut canyons generally in them, but in some cases the 
streams were wholly diverted from the old channels and cut new ones. 
Much of the Miocene deposits along the coast was removed during 
this stage, and valleys were cut across the continental border, which 
is now submarine, to the sea beyond. 1 The date of this erosion is 
indicated as occurring between the Miocene (Empire epoch) and late 
Pliocene (Battery Point epoch) by an unconformity at Battery Point 
near Crescent City. The intensity of the erosion during the continen- 
tal border stage must have been greatest near the sea. Its most 
pronounced effects on the continental border, now submarine, must be 
largely obscured by later deposits along the coast. 
12. Post-continental border subsidence. — A subsidence of probably 
700 feet submerged the continental border and carried the land some- 
what below its present level, where it remained stationary for a while. 
13. Battery Point stage. — The fossiliferous Pliocene San Diego beds 
of Battery Point, near Crescent City, were deposited during this stage 
in shallow water unconformably upon a post-Miocene surface of ero- 
sion. The stage was probably a short one and was brought to a close 
by further subsidence. 
14. Post- Battery Point subsidence. — After the deposition of the 
Battery Point beds, perhaps with some oscillation, a general down- 
ward movement of about 1,500 feet ensued all along the coast of 
northern California and southern Oregon, submerging the coast to 
approximately the level of the Sherwood peneplain. This submer- 
gence must have had a profound effect upon the land drainage, and 
filled many of the narrow valleys to great depths; but although the 
exact extent of the subsidence is not known, as the coast was moun- 
tainous, the sea did not advance far inland before the end was reached 
and the return swing began, which is recorded in the elevated beaches 
of the following stage. 
15. Marine-terrace uplift stage. — The marine- terrace stage opened 
apparently with the Sherwood peneplain near sea level, and from 
that position the land has risen to its present altitude, not by one 
1 Two papers recently published, one by W. S. Tangier Smith in Science, the other by O. H. 
Hershey in the Journal of Geology, should be referred to in this paper, but they are not avail- 
able while proof is in hand, in the field, and can only bo mentionod in this place. 
