Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/66

38 F³. school house. It was likewise noticed on Little Cocalamus creek near the forks of the stream in Monroe township, about 2½ miles south of Evandale, beyond which it is obscure to Troutwell in Suyder county.

It is one of the two principal synclinals in Juniata county, the second and more southern one being that of the Tuscarora valley, to be presently described.

14. The Academia anticlinal is a saddle of Clinton rocks scents from Reed’s gap on the west to Cocalamus creek on the east, and passing just north of the village of Academia in Beale township.

It is first noticed by lifting to daylight the Ore sandstone and accompanying measures just northeast of Reed’s gap, and eastward gradually spreading the opposing ore outcrops still further apart. Thus at Academia the two outcrops are just a mile apart, the south dip being 40° and the north one 60°, with the crest of the axis midway, exposing much flatter dips. The outcrops are even slightly more apart on Licking creek, where the dips are 30° and 40°; but the subsidence is then more rapid, the Ore sandstone being carried under between the river and the turnpike, beyond which successively higher measures straddle the crest of the anticlinal.

At Van Wert the dips are 40° north and 30° south, and the opposing outcrops of Lower Helderberg limestone are now only about a mile apart and then finally come together on Delaware run, after slightly crimpling along the crest of the axis. Still further east the axis is lost in the wide slate valley of No. VIII, where the exposures are scarce, unless perhaps it be merged with the Georgetown axis seen at the extreme end of the county, elevating the limestone No. VI and sandstone No. VII at the mouth of Mahantango creek for nearly 2 miles from the river and passing through Oriental and towards the Seven Stars Hotel.

15. The Tuscarora synclinal, like the main trough of the Lewistown valley, is more shallow and narrow in the middle of the county on the river, and deepens gradually towards both ends, its basin always occupied by Devonian rocks, and in the main a simple and regular synclinal.