ASPHALT DEPOSITS OF PIKE COUNTY, ARK 
By C. W. Hayes. 
The Trinity group, which is the lowest member of the Cretaceous 
in Arkansas, Indian Territory, and Texas, consists largely of coarse 
unconsolidated sands with some beds of clay, and is overlain by 
highly fossiliferous limestones. In Arkansas the Trinity beds rest in 
an almost horizontal position upon sandstones and shales of Paleozoic 
age. These older rocks have been intense \y folded, the dips being 
from 50° to 90°. After the folding, but prior to the deposition of the 
Trinity sands, much erosion took place, so that the Trinity beds were 
I deposited on an uneven surface composed of these folded Paleozoic 
rocks. Both Trinity and Paleozoic were, at a still later date, covered 
by a thin and irregular deposit of coarse sand and gravel called the 
Lafayette. 
At many points in the area under discussion the sands of the 
Trinity group contain notable quantities of bituminous matter, 
usually in the form of asphalt, though in Texas small quantities of 
petroleum are reported to occur at this horizon. 
The most extensive of these deposits occurs in Pike County, about 
2^ miles southeast of Pike City, on a branch of Wolf Creek. This 
has recently been developed by the Arkansas Asphalt Company, of 
Little Rock. Two hills south of Wolf Creek contain in their upper 
portions the fossiliferous limestones of the Lower Cretaceous, and 
around their bases and extending under them is the Trinity sand. 
The asphaltum deposit occurs in a depression between these hills, 
where only the lower portion of the Trinity formation remains, con- 
sisting chiefly of coarse sand, in some places quite calcareous, with 
beds of clay. The deposit is in the form of a sand stratum, which 
varies in thickness from to 12 feet, more or less thoroughly 
saturated with asphaltum. The deposit was discovered by the escape 
of small quantities of asphaltum to the surface in a spring, and this 
led to prospecting for its source. A pit was dug about 12 feet in 
depth, passing through the bed, and the thick, viscous asphalt has 
slowly oozed out into this pit for the last thirty years. 
The asphaltic rocks show considerable variation in character and 
in the amount of asphaltum which they contain. This variation is 
shown by the following analyses made for the Arkansas Asphalt Com- 
pany by G. W. Howard, of New York City. 
Bull. 213—03 23 353 
