Throughout the greater part of western New York the contact of Siluric with Devonic strata is traceable in the northward facing escarpment of the Onondaga limestone terrace. This terrace is a good example of a cuesta developed on an ancient coastal plain, the drainage adjustment of which has been greatly modified by glacial deposits. The northward facing scarp or “inface” of this cuesta is a prominent topographical feature of western New York, paralleling that of the Niagara cuesta which lies from 15 to 20 miles farther to the north.
The inface of the Onondaga cuesta first appears in Erie county, in the northern part of the city of Buffalo and a mile or two east of the Niagara river. Between this point and the river, extensive drift deposits have obscured the cliff, which, however, has been definitely located by excavations and borings.* From the point of its first appearance on Scajaquada creek . . .