[ Bead before the Texas Academy of Science , June 15, 1897.'] 
SOME TEXAS OIL HORIZONS. 
BY E. T. DUMBLE. 
While the production of oil in Texas has not yet attained a very 
great importance, it is, nevertheless, a fact that there are a number of 
productive oil horizons, several of which will sooner or later form the 
bases of profitable industries. 
These horizons are not confined to any^ particular geologic era or to 
the beds of any one formation, hut extend over almost the entire geologic 
scale from Lower Carboniferous to Eecent. 
The lowest productive horizon with which we are acquainted is that 
of the Bend division of the Carboniferous, which, by one or two paleon- 
tologists, has been assigned to the Sub-Carboniferous. The outcrop of 
the beds of this division in Texas has not a very great areal extent, and 
its best and most characteristic exposure is found along the San Saha 
river, from near the postoffice of Bend in San Saha county (whence it 
takes its name) to Brady in McCulloch county. The top of the deposit 
consists of highly bituminous shales, and some indications of oil are 
found in it. It dips to the north and northwest, and is covered in that 
direction by later beds of Carboniferous and Cretaceous sediments. Some 
of these beds are porous limestones, which form excellent receptacles 
for the oil and gas which are distilled from these shales, and wells at 
various places have tapped such reservoirs and secured oil in different 
quantities. 
In the Reports of the Geological Survey a number of localities have 
been given where oil and gas have thus been found. The principal 
localities are Waldrip, Trickham, and Brownwoocfi At this latter place 
two wells are sunk, 1643 and 1838 feet deep respectively, and small sipes 
of oil and flows of gas were obtained. In both wells oil was obtained 
in the beds of the Bend division* as well as in the more porous materials 
overlying them. 
Beds of the same age were recognized in the Indian Territory by the 
* Fourth Annual Report Geological Survey of Texas, pp. 436, 437. 
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