54 ECONOMIC GEOLOGY OF AMITY QUADRANGLE, PA. 
near Kammerer, 1,907; southeast of Munntown, 1,925; arid at Fin- 
leyville, about 1,967 feet. This progressive thickening of the interval 
toward the south and east is shown by isochore lines in fig. 3, as 
interpolated from well records. At all points along a given line in this 
figure the interval from the coal to the Gantz sand is equal, and it 
thickens or diminishes 20 feet for each line. 
The interval from the top of the Big Injun sand to the top of the 
Gantz varies from 574 to 751 feet, the extremes being, respectively, 
the well on the Harding lot at Washington and the Gamble well near 
Kammerer. In single instances considerably greater intervals have 
been observed, but these are believed to be due either to poor records 
or to a mistaken correlation of the sands. In North and South Stral 
bane townships the interval varies from 675 to 710 feet; in the 
borough of Washington, 574 to 670 feet; in the Fonner field, 719 to 
748; near Zollarsville, 650 to 722; in the vicinity of Deemston, 630 to 
720; and southwest of Beallsville, 650 to 700 feet. In a comparison 
of these groups of measurements the most noticeable feature is that, 
unlike the intervals from the coal, they do not show any general 
thickening toward the southeast. This fact is in harmony with the 
view that the thickening of the strata is due principally to an uncon- 
formity at the top of the Mauch Chunk formation. 
The Gantz sand has probably furnished a greater number of pro- 
ducing wells than any other sand in the county. The great majority 
of the wells in the Washington field obtained their oil from it. In some 
places the sand has two or three "pay" streaks a few feet apart. An 
immense quantity of oil has been produced from the Gantz, some of 
the early gushers having flowed hundreds of barrels the first day. In 
several eases the production the first twenty-four hours reached 2,000 
to 3,000 barrels. 
The Gantz sand is also the principal producing sand of the Fonner 
field, where it furnishes both oil and gas. In this part of the quad- 
rangle, however, the Gantz and Fifty-foot are frequently found in 
contact, forming the Hundred-foot. The Gantz sand also produces 
gas in a few wells in the Zollarsville and Somerset fields, and it is the 
principal gas sand of Chartiers Township in this quadrangle. 
Fifty-foot sand. — This is the lower division of the Hundred-foot 
and has a wide distribution in the Amity quadrangle. Under this 
name drillers of ten include the Gantz in wells where the two sands are 
combined. The Fifty-foot sand itself locally splits into two sands. Its 
distance from the bottom of the Gantz sand varies up to 80 feet, being 
greatest toward the southeast. Where distinct from the Gantz, the 
sand is here and there as much as 100 feet thick, though generally 
thinner. 
The distance from the Pittsburg coal to the Fifty-foot sand varies 
from 1,807 feet in the Matthew Linn well at Washington to 2,057 feet 
in the Burkehammer well in the borough of Deemston. This interval 
