Oscillations of the Calif ornin Coast. — Fairlnoiks. 233 
the mouth of the arroyo. Both of these valleys are so situat- 
ed with reference to the alluvial bottom that a structural or- 
igin does not appear possible. 
The conditions at Santa Catalina island bear out exceed- 
ingly well the view of a former elevation. The submarine 
contours around the island have a curve very similar to that 
of the shore, indicating an extension of the main features of 
the topography to a depth of over 300 fathoms. The island 
is very steep, and rugged and the absence of terraces is no 
proof, as Lawson seems to think it is, that the island was never 
submerged. Mr. W. S. T. Smith* has recently shown that the 
land was submerged during the Miocene as much as 1400 
feet below the present level and that in the recovery from the 
depression, at least one terrace was formed. He also expresses 
the opinion that in pre-Miocene times the island was elevated 
2000 to 3000 feet above the present level. A recent subsid- 
ence is shown to have taken place amounting to about 350 
feet. Thus many facts go to show that the history of the is- 
land in a general way corresponds to that of the mainland. 
The same thing is probably true of the Santa Barbara islands. 
The submarine contours about these islands from 100 to 300 
fathoms dpwn accord ver}^ well with the present shore con- 
tours. 
At Carmelo bay, some distance northward, occur the next 
known submarine valleys extending close in to the shore. By 
Lawson they have been ascribed to faulting. He says:f "At 
Carmelo Bay there is no evidence of an elevation of this part 
of the coast since Miocene times exceeding the present alti- 
tude." There are two branches of the submarine valley oc- 
cupying the bay, the larger and deeper of which lies to the 
south opposite the mouth of the San Jose creek. The valley 
of this stream extended seaward would accord exactly with 
the submarine depression. 
The great valle}'- extending east and west through the ba}^ 
of Monterey reaches from near the mouth of the Salinas river 
down to an unknown depth, probably across the plateau to 
the abyssal depths of the ocean. This valley is also consid- 
ered of structural origin by Lawson as the Miocene strata on 
*Proc. Cal. Acad, of Sci. in Series, Vol., p. 69. 
tBull. Dpt. of Geol., Univ. of Calif., vol. I, p. 58. 
