Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/276

248 F³. north of Lillyville, the main valley south of Belltown deepens to receive a larger section of the rocks of No. VII; so that the central line of the trough is strongly marked by the presence of a prominent ridge of Hamilton sandstone, quite overriding the Oriskany ridge at Belltown where No. VII is thin and slaty,

The Belltown school is situated on the crest of a sandstone ridge associated with the Hamilton rocks, and a good view of the Clinton terrace on Jack’s mountain can be had from this point. In Belltown proper the Marcellus black slate crops along the road, with a southeast dip varying between 65° and 80°, within 300 yards south of the Oriskany sandstone ridge. This is the only evidence that the anticlinal west of the village of Decatur is still in force at this point. The dip is almost immediately reversed going down Belltown run. Further east the Oriskany ridge becomes more and more subordinated to the Hamilton ridge as it approaches closer to the mountain.

The Medina IVe crest of Jack’s mountain is gapped for the first time east of Logan gap near the Snyder county line,

Crossing the valley from this point to Wagner station the main synclinal is well marked on a 70° S. E, dip near D. Yetter’s house by a good outcrop of slate in a branch of Jack’s creek; and on a reverse dip of 35° N. W. in a good exposure of the same brown slates, 20′ thick, just at J. Yetter’s mill dam.

The Oriskany ridge on the south side of the valley is quite low, and is only indicated by the frequent occurrence of slaty sandstone bowlders embedded in loose sand. No. VII cannot be over 50′ thick in this portion of the valley. And hereabout, together with the limestone south of it, it must have a rather low dip.

The road from Wagner to Shindel runs along the north flank of this Oriskany ridge, which however is entirely obliterated in front of Oswell’s and Mowry’s gaps, and does not take form again until at the junction of the Lillyville road, where the Oriskany sandstone shows in a bluff