GENERAL GEOLOGY OF BURGETTSTOWN QUADRANGLE. 45 
sand, belong to the Pocono formation. About 100 feet below the 
Hundred-foot is the 1 hirty-foot sand. This has produced oil in a 
portion of the Burgettstown oil field and lias yielded gas at other 
places in the quadrangle. About 210 feet below the Hundred-foot 
sand is the Gordon, which is the principal producing sand in the 
southeastern portion of the quadrangle. Along the southern border 
of the quadrangle an extra sand appears a few feet above the top of 
the Gordon, and is called the Gordon Stray sand. At a distance of 
about 60 feet below the Gordon sand is the Fourth sand, and about 
120 feet below the Gordon is the Fifth sand. Both of these lower 
sands are producers in the eastern portion of the quadrangle, but have 
been reached in only a few places in the central portion and in these 
have been found unproductive. 
DISCUSSION OF CONDITIONS AS SHOWN BY MAP OF HUNDRED- 
FOOT SAND. 
DESCRIPTION OF MAP. 
A contour map of the top of the Hundred-foot oil sand constitutes 
PL IX. The contours that represent the upper surface of the sand 
are printed in red on the topographic base map. These contours do 
not extend fully over the map, owing to the lack of reliable informa¬ 
tion in the northeast corner of the quadrangle for constructing a con¬ 
vergence sheet* The vertical ‘interval between the contours is 10 
feet. The numbers upon them represent the elevation from a datum 
plane 2,000 feet below sea level. This datum plane was adopted to 
avoid the use of the minus sign. The wells drilled in the quadrangle 
are represented by the accepted symbols for dry holes, producing oil 
wells, and gas wells. These symbols are printed in two colors—red 
and blue. Those in red represent wells that have been drilled no 
deeper than the Hundred-foot sand, and where they are known to 
have stopped in one of the sands above the Hundred-foot, a red cross 
is placed to the right of the symbol. The symbols printed in blue 
represent wells drilled to the Gordon, Fourth, or Fifth sands. 
CONDITION OF SATURATION. 
The wells of this region show that the Hundred-foot sand contains 
little, if any, salt water within the Burgettstown quadrangle. Since 
the producing sand is generally dry, the oil should be found in the 
svnclines rather than in the anticlines. This condition is found to 
*/ 
exist. Of the three pronounced synclinal basins in a north-south line 
through the middle of the quadrangle, two contain oil pools of con¬ 
siderable size; the third has by no means been thoroughly tested. 
