302 GEOLOGY OF OHIO. 
have been undermined and. dropped below their proper horizon ; glacial 
strice on their surface south 35° east. | : 
Near Plymouth village, the Berea crops out on the banks of the stream, 
showing massive rock about twelve feet in thickness, nearly horizontal, 
and of good quality. At Edgar Bovier’s quarry, just east of the village, 
the rock is in thin horizontal layers, becoming thicker as the opening is 
carried downward; color, grayish blue, many of the layers affording a 
sharp grind-stone grit. Here, and at openings further north on the river, 
streaks of coaly matter, derived from plants, are not infrequent in the 
Berea. The rock is here unaffected by glacial action, but the disturbance 
becomes very marked further down the river. At G. Graham’s quarry, 
in Greenfield township, the rock dips 133° south-westerly, with the line 
of strike south 35° east, is in very even layers, all finely ripple-marked, 
some with that puzzling mammary surface, probably caused by the action 
of eddies where “two seas met” on the old ocean shore. Following down 
the stream the dip increases in fifty rods to 374°, then diminishes to 104°, 
increasing again till the layers become almost vertical (standing at an 
angle of 75°), with the line of strike south 29° east. 
The following is a section of the Berea grit and the rocks expesed 
below it at this place: | 
Ss . Fr. 
LSet oie SPM rae 
ea A Drift. 
Bereas evenly shed ded ce marie geese nein send Re 25 to 30 
Turtle- backs sagen uae Sc ciues a8 ara Ue ca Sree ein 3 
Sandy shale, alternating with argillaceous shale...... 6 
Evenly bedded sandy shale...-....----+--e---+ Het 8 
Argillaceous shale, with bands of hard rock........-- 28 
‘ ; 
ne é 
Turtle-backs, in three layers :--25... 2.2226 oe ee-ee-e 8 t0 10 
Evenly bedded shale----....-2:.------...-2-- weet raicioe A) 
Turtle-backs, in soft argillaceous skale........-----.+- -3 
SoS Shaly sandstone, waved and’ ripple-marked.........- 20 
Hard sandstone, with thin layers of soft shale........ «6 to 6 
Blue blackyshalewsee a aeee ee eee sale nee eecinaiaiciaaiatays 20 
Shaly sandstone ..---..-.--------- oe ee 2 
Argillaceous shale AEN ATIC Eta nou Maat ce 1 
