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 bluff 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 nearly 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 2 l / 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 was 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. 3 
Across the river and lying 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. 
