a 
- - 
v 
California Tertiary Formations.—Hershey. 371 
Dr. H. W. Fairbanks traced this pink conglomerate and 
sandstone west along the southern border of Antelope valley 
and at Rock creek, nearly midway between Cajon and Soledad 
passes, he collected marine fossils from a stratum conformably 
resting ‘on the typical reddish sandstone. These fossils were 
shown to Dr. J. C. Merriman who thought they possessed an 
Eocene facies, but the material was meager and nothing very 
definite can be based on it especially as the shells have been 
mislaid. Dr. Fairbanks is confident that the fossil-bearing 
stratum belongs over some and is a part of the reddish sand- 
stone series. and cannot have reached its present position by 
thrust or by an overturn. 
In 1875, Mr. G. K. Gilbert described* from Red Rock 
canyon on Mohave desert, not very far north from the line 
which I followed, a series of rhyolyte lavas and tuffs over- 
laid by sandstones and more basic tuffs, which seems to be 
the counterpart of my section at Daggett. Dr. Fairbanks has 
studiedy the same region and from a similar series southeast 
of Black mountain, he has collected impressions of leaves, 
which were submitted to Dr. F. H. Knowlton, who says, 
“they seem to belong to the Eocene.” 
Dark brown, massive, basic lava like that of the Soledad 
region occurs unconformably under Miocene sandstone in Cal- 
menga pass near Los Angeles. On San Clemente island? 
there are basic lavas overlaid by “‘fossiliferous, white limestone, 
which may be the equivalent of the Miocene of the coast.” 
The same volcanic series seems to be heavily developed on 
Santa Catalina island. Mr. Homer Hamlin told me that he 
has found at different places in southern California under un 
doubted Miocene strata just such a basic volcanic series as I 
have described from the Soledad region. Prof. A. C. Lawson 
has called my attention to the presence near the bay of San 
Francisco of a rhyolyte occupying the position of the Eocene. 
It is thus evident that there is precedent for finding Eocene 
volcanic material both acidic and basic in southern 
California and the Rosamond and Escondido series may well 
be tentatively placed in that group. The evidence is very meag- 
* Geographical Survey West of the 100th Meridian, vol iii, p. 142. 
7 AMERICAN GFOLOGIST, vol. xvii, February, 1896, p. 68. 
t Bulletin ‘of the Department of Geology, University of California, vol. i, 
No. 4, p. 133. 
