Jcuiez — Albuquerque, N. Mex. — Regan. 79 
izon, the Puerco again appears ; but its thickness is not great. 
This Puerco also occupies the valley of Salt River from near 
Ojo del Espiritu Santo to Mesa Blanco. Beneath the Puerco 
east of Cabizon is the Fort Union formation. It is also seen 
in places to the v^est of the Rio Puerco. It is exposed, for the 
most part, along faults. The principal exposure is along the 
fault both north and south of the Fox Hills. It extends from 
the village of Nacimiento in a southerly direction beyond Mesa 
Blanco. Passing south of the Jemez river, orange colored Cre- 
taceous sandstones and shales overlie Mesa Blanco at the 
south ; and extend east as an outcrop along the Zia mesa break, 
till their dipping strata pass out of sight beneath the Pliocene 
deposits of the Jemez valley. On the Rio Grande the Cretace- 
ous orange beds appear along the tributaries of that river 
which come in from the southeast from the vicinity of Tejon. 
These beds are exposed in the bottoms of the canyons only. 
East of Tejon another Cretaceous area appears superimposed 
upon the Jurassic series, as we have already noticed. This 
area extends east and north farther than was visited. Its 
strata are repeatedly faulted, thus exposing the same strata in 
vertical section time after time. It is coal-bearing, but the beds 
are not thick. The coal is bituminous, but poor in quality. It 
is mined in 'Several places. On inquiry it was learned that 
farther northeast the coal seams are thicker, and that the coal 
is of better quality. It was furthermore learned that the car- 
bonaceous slates above the coal seams are not so thick there. 
This cretaceous is Laramie or Fort Union. 
Considering the Cretaceous west and southwest of the 
Nacimiento mountains more in detail, we will treat them in 
their order of deposition as follows : Fox Hills, Fort Union 
and Puerco marls. 
The Fox Hills. — As has been previously stated the Fox 
Hills extends from near the Jemez group of mountains west 
of Jemez peak to the Rio Puerco, and then south down that 
river. It was a ridge in Fort Union and Puerco times, which 
extended west as a peninsula from the Nacimiento mountains 
to a cretaceous area lying beyond. The Fox Hills dips west 
from the Nacimiento mountains in the peninsula part; but, af- 
ter passing south of Cabizon, it dips northeast to the east of the 
Rio Puerco, and on the west side of that river it dips south- 
