20S A'. M. Kindle— Slratigraphic Relations of the 



ally high arch just west of Eagle Point and another at Beach 

 Park rise 20 feet or more. Detailed study of this lake shore 

 section has shown that the east and west limbs of the series 

 of low anticlinal rolls which succeed each other for more than 

 S miles are essentially equal, and that for this distance the base 

 of the Cleveland shale shows no westerly declination between 

 Eagle Cliff and Lake Breeze. 



In the vicinity of Lorain and for several miles to the west- 

 ward the shales are concealed along the lake by glacial deposits. 

 The shale cliffs reappear again, however, near the mouth of 

 Vermilion River. Here along the shore east of the river the 

 broad, low anticlinal rolls, similar to those which have, just 

 been described, prevail. These are interrupted by a fault 

 which brings the Berea sandstone down to lake level and 

 beneath which it dips at 45°. One other locality is known at 

 East IMorwalk, at the Shed and Perry quarries, where deforma- 

 tion has resulted in strong dips. There the Berea sandstone 

 dips on the limb of a synclinal trough at 37° toward the south- 

 east. Such strongly developed folds are very exceptional, how- 

 ever, the normal structure west of Pocky Piver being the very 

 low rolls already described. Between the Vermilion and Huron 

 rivers few if any exposures of the shale occur. West of the 

 Huron River about 2 miles, the lowest and most westerly beds 

 of the Ohio shale which are exposed along the lake shore reach 

 the surface. Here the typical Huron shale with numerous 

 large spherical concretions borders the lake. Since the Huron 

 shale east of this point is everywhere below lake level, there is 

 between the Huron and Vermilion rivers evidently some 

 easterly dip of the surface beds. The more essential facts 

 developed in this study of the structure of the Lake Erie 

 section of the Ohio shale may be briefly summed up thus : 

 At the western end of the section the shales have their mini- 

 mum thickness and for a short distance eastward their upper 

 and lower beds maintain an approximately similar easterly dip 

 corresponding to that of the limestone floor, which is between 

 30 and 35 feet per mile in the Huron River valley. With the 

 thickening of the shale eastward the dip of the upper or 

 Cleveland shale division exposed along the lake shore ceases to 

 correspond to the lower beds of the shale, which must continue 

 to approximate the easterly dip of the limestone base. These 

 upper beds for a considerable distance east of the Vermilion 

 and Black rivers are characterized by a series of minor very 

 gentle north and south rolls, but their total declination east or 

 west is approximately zero. This is the result apparently of 

 the easterly thickening of the shales keeping pace with the 

 declination of the limestone toward the east. Near Rocky 

 Piver and thence eastward for about 40 miles bevond Cleve- 



