Oscillations of the California Coast. — Fairbanks. 243 
been found to others where we know the character of the 
strata but have no record of fossils. I think then that we can 
lay it down as a general fact that all the stream valleys open- 
ing out to the coast are filled to a very considerable depth 
with undisturbed deposits of Pleistocene age. In the plains 
of Santa Ana and Los Angeles artesian wells are found seve- 
ral hundred feet in depth passing through unconsolidated ma- 
terial. In the Santa Maria valley the wells reach down 200 
to 300 feet passing through sands and gravel having the same 
almost level position as the surface of the valley. How much 
deeper this formation is we of course do not know. In the val- 
leys of the Salinas and a few miles from the ocean is a well, 
reaching a depth of 1300 feet. The character of the strata 
passed through seems to be very similar to that shown by the 
deep wells of Stockton where they are believed to be of Pleis- 
tocene age. From Watsonville west to the ocean are artesian 
wells 70 to 256 feet deep lying in the flat bottom of the Paia- 
ro valley. Numerous artesian wells have been put down the 
whole length of the Santa Clara valley and on both sides of 
the southern arm of San Francisco bay. They vary in depth 
according to position from 100 to 700 feet. Remains of Pleis- 
tocene mammals have been obtained in addition to marine and 
fresh water shells. 
I think that in general there can be no doubt that these 
wells are confined to the undisturbed Pleistocene beds filling 
the earlier eroded valleys. The water coming down the pres- 
ent streams begins to percolate downward, as soon as the 
bedrock is passed, into the sand and gravels, the sedimenta- 
tion lines of which conform to their original slightly sloping 
position, the position in which they were deposited during 
the greater elevation of the early Pleistocene, The beds of 
coarse sand, pebbles and sometimes boulders passed through 
in the Salinas well as in the Great Valley indicate that depo- 
sition followed close upon subsidence, and that a much 
greater elevation must iiave existed. 
Conclusion. 
It is believed that the above discussion has completely sub- 
stantiated the view first advanced by professor Le Conte of a 
greater elevation of the coast during the earl}' Pleistocene. 
