Geological Recomioissance i?iN.M. — Herrick. 345 
to a point west of Crater Lake and connects eastward with the 
great Cretaceous area west of the lava beds. This Cretaceous 
is of Fox Hills age and carries lignite beds of considerable 
thickness. \''ery characteristic of the middle portion of the 
sheet is the great flow of basalt which extends in a south- 
westerly direction from San Rafael for nearly fifty miles. Evi- 
dently the great valley to the west of the high Cretaceous 
mesa forming the eastern boundary of the sheet had been ex- 
cavated prior to the flow, for in some places, especially to the 
north, the impotent waves of congealed lava can be seen at 
the very foot of the abrupt escarpment with all the evidence 
of movement still visible upon the surface of the flow. The 
tongue of granite thrust in from the north is surrounded by 
Carboniferous strata capped by the Permian. The red beds 
appear in the hills on the west side of the lava near San Rafael 
and evidently the red series extends below the lava, for it ap- 
pears in many places under the Cretaceous east of the lava. 
The road lies at the foot of the cliffs and passes through 
the narrow interval between the clififs and the lava beds, in 
some cases traversing the latter for short distances. As we 
pass northward the top of the red series emerges, so that we 
are able to examine the lower Cretaceous very satisfactorily. 
Here, however, a member of the series appears which was 
not seen elsewhere in the course of our journey, viz: the Da- 
kota sandstone. The entire thickness of this sandstone is here 
not over 75 to 100 feet, and the red sands and marls below are 
evidently of the vermilion beds. The Dakota itself is a rather 
coarse, massive and pulverulent yellow sandstone which tends 
to assume mural and grotesquely architectural forms in the 
numerous outliers. It is followed by 25 feet of white sand- 
stone like that forming the base of the series in the Puerco 
valley. 
Above the Dakota the succession seems to be as else- 
where in this region. Crossing the Cretaceous mesa we reach 
the railroad at McCarty's, pass down the river to Laguna 
with its curious combination of pueblos and modern depart- 
ment stores and thence turn northward to skirt the great 
l)asalt sheets extendin.g eastward from Mt. Taylor. The small 
dykes cutting through the Cretaceous strata in this region 
and the s'reat necks of basalt here and there visible have been 
