LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON

CRETACEOUS SEDIMENTARY EIVTSIONB 75
menfc seems to htva suffered a partial withdrawal of the sea, whereas the withdrawal
from the Sacramento embayment was leas complete, and deposition of sediment
continued locally almost uninterrupted.
(2) Mid-early Cretaceous movements, differential in their effects, followed by
widespread subsidence ID central California and along the Paeifia Coast between
Alaska and Mexico, if not also far to the south, seemed to have opened new gateways
into the Great Valley embaynienta Their principal areas and also their lateral
brunches extendi up into the surrounding land were then flooded, in alt of which the
deposits of this early epoch were laid down. At many points on the borders of these
etnbaymeate local conglomerates mark the points of stream entrance from the
adjacent lands, indicating that the latter were not affected by subsidence.