TERTIARY: FAUNAS*O2 Mile PACTEIC COAST 513 
It is a noteworthy fact that with one exception wherever the line 
between the marine Eocene formations (Martinez, Arago, Tejon, etc.) 
and the Cretaceous beds is marked by an angular unconformity, the 
underlying beds are either of lower 
Cretaceous (Knoxville) or middle Cire | ae 
Cretaceous (Horsetown) age, and Maniné ae / ~~~ et 
that wherever the Eocene rests on UI Fressowaren ae 
rl LAND oor : ome 
the Chico, or upper Cretaceous, ex- 
cluding the case at San Diego, the rey 
unconformity is not angular, and as |,.5> 
far as the stratigraphic evidence fe 
goes, the two formations represent 
an apparently uninterrupted period ==) Be / f 
of sedimentation. 3 Ma 
The apparent conformability of ) fa fi 
the Eocene on the Cretaceous, to- } iV 3 
gether with the superficial similarity 
of their faunas, led Gabb and |€é ey i 
Whitney of the early California Toe 
Survey to class the Martinez and 3 2 
Tejon formations with the Cre- 
taceous. White, Stanton, and Mer- . =e sl 
riam have, however, shown the |» <= a Gee 
Eocene age of the Martinez and ak: / 
Tejon. Of the relationships existing Bae eue —— : 
between these two and the Chico, Rarph Aenela 1804 os 
or upper Cretaceous, Dr. Merriam Fic. 1.—Map showing hypothetical 
has the following to say: distribution of land and water on the 
Pacific Coast of the United States 
during Eocene time. 
The Martinez group, comprising in 
the typical locality between one and two 
thousand feet of sandstones, shales, and glauconic sands, forms the lower part 
of a presumably conformable series, the upper portion of which is formed by 
the Tejon. It contains a known fauna of over sixty species, of which the greater 
portion is peculiar to itself. A number of its species range up into the Tejon 
and a very few long-lived forms are known to occur also in the Chico. Since 
the Martinez and Chico are faunally only distantly related it is probable that an 
unconformity exists between them.? 
t Jour. Geol., Vol. V, 1897, p. 775. 
