HAYES AND 
KENNEDY. 
DETAILED SECTIONS. 41 
Limestones also appear in the wells at Velasco at 785 feet and at 
Columbia at 156 feet. Whether or not these may be correlated with 
the Reynosa, sufficient knowledge is not yet available for determining. 
With the exception of the limestone reported in the Big Plill well in 
Matagorda County, no limestones are known to exist in this region, 
and the nearest Reynosa limestones occur at Rogers in Nueces County, 
at least 135 miles distant. 
It will be noticed that the first bed of limestone found in these wells 
lies in such a position as to appear in all. It is interbedded between 
two thick beds of clay, except in the Velasco well, where its under- 
lying bed is not known, and a thin bed of gravel intervenes between 
the clay and limestone. This limestone appears to be irregular in 
thickness. In the Guffey No. 1 and Herndon wells it does not show 
a thickness exceeding 4 to 5 feet. In the Columbia well the thick- 
ness recorded is 5 feet, but in the Damon Mound Oil and Pipe Line 
Company's well, about a mile south of the Herndon well, the reported 
thickness is 70 feet. Its thickness in the Velasco well is not known. 
From the depths given, this limestone appears to dip in a south- 
easterly direction from the summit of Damon Mound at the rate of 25 
feet per mile. On the northern side of the mound the dip is to the 
northwest at the rate of 93 to 95 feet per mile. About 8 to 10 miles 
northwest of the summit the same limestone comes to the surface in 
the bed of the San Bernard River. The beds shown in that locality 
are dipping toward the mound at a rate of approximately 33 feet per 
mile. Another noticeable feature of the region is the appearance of 
a minor fold in the Columbia field. The area or extent of this minor 
fold is not known. 
From these figures it would seem as if the regular dip of these beds, 
including the limestones as well as sandstones lying at greater depths, 
is southeast toward the coast. The dip is probably interrupted by a 
fold, and probably a fault at Damon Mound, beyond which the beds 
resume their normal southeasterly dip. 
How far to the east or west these folds may extend is not known. 
No drilling has been done to the west except at Big Hill, in Matagorda 
County, approximately 20 miles to the southwest. In the Big Hill 
well limestones occur at various depths, and it is possible that these 
are the same beds as those forming the minor fold in the Columbia 
field and that the minor fold has a length of at least 20 miles. From 
this it might be inferred that some traces of the main fold may be 
found lying in the same direction. 
Toward the east it is doubtful whether drilling would show any 
continuation of the Columbia well limestones. No drilling has been 
done in the line of the arch projected, but at Angle ton, a few miles 
to the south of such a line, the Brazos Valley Oil Company and New 
York and Texas Land Company have drilled wells, the former to the 
depth of 1,500 feet and the latter through sand and clay to a depth 
of 600 feet. 
