Dec, 1908.] Rock Terraces. 399 



closely today, but leaves a narrow flood plain at its base. East- 

 ward behind the terrace rises a seventy-five foot' blufl with a 

 steep serrate front. Bluff largely of Ohio shale, occasionally 

 exposed, with Olentangy covered at^the base. Terrace consists 

 of Delaware limestone apparently near top of formation, from 

 which the shales have been swept together with a little Delaware. 

 No quarries are opened in it, but a wagon road runs its entire 

 length. 



Across the river from the last and extending some distance 

 farther north, occurs a low, long, narrow terrace. It has a 

 length of one and one-half miles and a width of from 10 to 100 

 yards, and its front rises only 10-15 feet above the river. The 

 top descends very gently toward the river and also descends 

 15-20 feet from north to south. A thin sheet of alluvium, but 

 very little residual waste, on top. Many little runs descend 

 across it, mostly on rock. Terrace front almost one continuous 

 outcrop. Terrace is composed of Delaware limestone, and its 

 top is a structural plain, being almost exactly coincident with 

 the bedding planes. A good highway follows it from end to end. 



This terrace descends at its southern end so low that high 

 water rises over it, and it thus becomes flood plain for about one 

 mile beyond the point where it is distinctly a terrace above the 

 river. Thus treating flood plain and terrace together, since they 

 are one, we have a rock platform two and a half miles long with 

 its' southern end only 5-6 feet above the stream, while its northern 

 end is very nearh^ 30 feet above ; and adding to this difference of 

 24 feet, the fall of the river in the same distance, about 20 feet, 

 the terrace top is shown to descend about 45 feet in 21-2 miles, and 

 more than twice as much as the present stream falls. It follows 

 therefore, that it must have been carved when the grade of the 

 stream w^as much greater at this place than it is at present. 



Passing now to the Scioto near the northern boundary of the 

 area, there are three small terraces between Bellpoint and 

 Rathbone. The first is on the west side a mile or more south 

 from Bellpoint, and is almost 600 yards long and 200 yards wide. 

 It stands 15 feet above the river; its surface descends eastward 

 15-20 feet toward the river and 10 feet southward down stream. 

 It consists of limestone, and coresponds very closely with the 

 bedding planes. A quarry opened in it.^ 



Across the river and hang just south of the above terrace is 

 another of about the same size. It stands 25 feet above the 

 river, descends gently southward but not toward the river. Two 

 residences upon it. 



Passing back to the west side and down stream a hundred 

 yards, another long terrace may be found having a width of 



3. Geol. of Ohio, Vol. II, p. 294. 



