262 ANNUAL REPORT 
Thickness of Total 
stratum. thickness. 
Feet. Feet. 
Black: Shales mine tccen Gare cieosbere ener merece rene 10 310 
PSU NGS ere Snel ge ee a arene ENR eed eae ORS 25 335 
Shalemwithsconcreblonsiarcareer reine 100 435 
Noy EAs Rape CEL eR On mR een Aye Meee LA Ato cy ata eG 25 460 
LAMeStOn eu?) Baar ee ede ace ee nee ee erage 30 490 
Sale ays sarees yee tence ice roesa te rare Ree eter Ree Be 525 
SG1E- SANG Biwrkersceire isis Cid tlelorereieeee eRe hae etorers 30 555 
Wihitte- Slate aiisc sxccancksogetsliotten. bouelercko von erolensacnsnctens 100 655 
Slatemandsconcrebions meer eee 25 680 
SHA sie cee peat s Bieler or atelvene aie oder ake oe 15 695 
Little Salt sand (Big Injun)........ ees 20 715 
White, Slates cata crew picusiota siesta ever kets tee nwa 100 815 
SHENG) ENO! COMOGREHIOMS 5 o0000000000000000000 100 915 
Browmn.cshale tet e on Leek oes en eee 40 955 
Blackishale7@Benea) haere eee 38 993 
TOD) 2Ob (BeCREO se Botte ieocs cia ee eee 993 
Bottom :O Le BON Gace sictepeyetacle tiotercioe re Cio O ee 1,008 
The Oil Sand.—This is in all cases the Berea. It has the light gray 
color so common in this formation in other parts of the state. It is moder- 
ately fine grained, but there is considerable variation in this respect. 
Usually it is a pure quartz sand, but occasionally has thin layers of dark 
shaley material running through it. In thickness it shows considerable 
variation, but never disappears in this field. The normal thickness is. 
usually given as twenty feet and the maximum reported is eighty. This 
depth was found on the Potts farm about one and one-fourth miles north- 
east of Corning, and on the O’Farrell farm about two miles east from the 
same town. In both cases a dark gray shale, probably the Ohio, lay 
below. The Bedford on this theory had been swept away before the 
Berea was deposited. In such abnormal depths the additions always appear 
to be on the bottom, showing that the surface of the underlying Bedford 
shale was quite uneven. It is worthy of note that the production of oil 
does not vary as the thickness of the sand. In fact, in this field the great 
thicknesses are generally poor producers. 
The pay-streak, or that containing the oil and gas, ranges in thickness 
from 3 to 8 feet, but very few wells attain the maximum figure. Towards 
the margin of the productive field the pay-streak thins, and finally disap- 
pears. The top of this usually lies from 10 to 15 feet below the surface of 
the Berea. As a rule the pay is coarser than other parts of the Berea, 
and generally the coarser the rock the larger the well. Sometimes in the 
thick part of the Berea there are two pay-streaks. 3 
The Oil Wells.—The number of wells producing July 1, 1900, ex- 
ceeded 600; August I, 1902, it was 688. About too dry holes have been 
drilled and about an equal number of wells have been abandoned, so that 
goo is a fair approximation of the total number of wells drilled. As a 
rule a well has been put down for each 8 or 10 acres of surface territory. 
