274 The American Geologist. Novombt^r, 1896 
then iuul is still related to the mountains of southern Califor- 
nia? If it can be shown that the ditferent aggregates of 
strata occurring there, and representing the main geological 
divisions from the Jurassic, or even earlier, are separated 
from each other by non-conformities, there are then the most 
excellent reasons for believing that, in marked contrast to the 
Great Valley which was probably continuousl}'^ beneath the 
sea, the Coast Range region has been subject to repeated axial 
elevations and depressions, now above the sea, now more or 
less submerged. We must not think of these movements as 
of a uniform character, affecting all parts alike, but while 
orogenic, or even epeirogenic in extent they were also locally 
intensified. 
In all probability the sag once inaugurated between the 
two great ranges constituting what has been termed the 
Great Valley has never been structurally obliterated. 
Nothing is clearer in the study of the Coast ranges than 
that there have beefi enormous movements of the coast as a 
M-hole, us well as differential movements of large magnitude, 
whereby new local ranges have been formed by the side of 
more ancient ones without greatly affecting them. 
The supposition which Mr. Ransome advances concerning 
the possibility of the Cretaceous sediments having been depos- 
ited in greatest thickness over the region now occupied by 
the summit of the Coast ranges is hardly supported by the 
facts. It is possible that the sediments may once have 
mantled over a portion of what is now the Coast ranges west 
of Colusa county, but it is quite certain that the region 
toward the coast was above water because of the entire ab- 
sence of the lower Cretaceous and the fact that the Wallala 
beds rest directlj^ on the Golden Gate series with a basal con- 
glomerate. 
The statement in the quotation from Mr. Ransome that Mr. 
Diller probably hardly means to convey the impression that 
there was any distinct valley during the Shasta-Chico depo- 
sition is rather strange in the light of the following quotation 
from the same paper of Mr. Diller* where in speaking of 
the view held by Fairbanks that the Coast ranges and the 
Sierras were upheaved at the close of the Jurassic he says : 
*Bull. Geol. See. Am. vol. v, p. 455. 
