78 
PENNSYLVANIA AND NEW YORK DEVONIAN. 
[BULL. 120. 
Table showing the geologic position and character of the formations composing the Devonian 
system of eastern Pennsylvania. 
Lowe r 
Carbon- 
iferous. 
Pocouo. 
Mount Pleasant conglomerate . . 
About 50 feet 1 in thickness. 
3 
OS 
o 
Mount Pleasant red shale 
Red shale interstratihed with greenish-gray 
sandstones; 300 feet in thickness. 
Elk Mountain sandstone and 
shales. 
Greenish sandstones and shales ; 200 feet 
(»>. 
Cher 
Ped arenaceous shale at base with two mas- 
sive conglomerate layers at top separated 
by shale; 325 feet (?) . 
© 
Hon 
Somewhat pebbly sandstones, with some 
shaly, reddish sandstone. 
CD 
j 
3 
o 
> 
fcl) 
a 
i 
6 
& 
1 
d a; 
§| 
£2 
Oft 
« s 
.5 S 
<D 
be 
<? 
H 
O 
ft 
Mainly red shale, but some greenish argil- 
laceous shale. In upper part highest fos- 
sils, Spirifera mesastrialls Hall. 
p 
e 
Greenish gray thin sandstones and shales 
with some red shale. Orthonota (?) parvula 
Hall in lower part; 1,200 feet. 
New Milford shale 
Ped shale ; 100 feet. 
Starucca sandstone 
Greenish gray massive sandstones ; 600 feet. 
Chemung (of White) 
( Paracyclas lira ta stage ( ? ) 
of lower Portage, Prosser). 
Olive and gray micaceous sandstones, with 
thin arenaceous shales, moderately fossil- 
iferous; 1,150 feet (?). 
i 
d 
o 
1 
eg 
w 
Genesee shale. )- w - aT1+ i 1 ,„ 
Tully limestone. Ranting. 
a 
o 
> 
P 
Genesee shale (of (Hamil-1 
White); Tully lime- 1 ton of 1 
stone (of White); Ham| Pros-j 
ilton (of White). [ ser. J 
The lower part consists of thin sandstones and 
arenaceous shales; next is a somewhat cal- 
careous zone, and at the top argillaceous, 
fossiliferous shales; 1,400 feet. 
3 
Mar 
The lower shales are grayish, becoming very 
dark in the upper part ; '800 feet ( ? ) . 
2 
o 
Upper Helderberg (Cornifer- 
ous limestone) . 
Cherty limestone; 200 feet. 
•3 s 
p 
Cau 
O 
1 The thickness of the formations given in this table is in the main the same as that given bv Prof. 
White in G 6 (see p. 76, etc.). 
