Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/236

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208 F³.
E. V. d’Invilliers, 1889.

of the Marcellus black slate and Hamilton sandstone, and also some shaly impure limestone south of the blacksmith shop, which is probably Marcellus and shows some indication of carbonate ore. The dip here is about 50° N. W.


The Hamilton sandstone makes a prominent ridge whose rocks are well exposed again on the river about 1½ miles above McKee’s Half Falls and perhaps three-quarters of a mile above the ferry. The exposure here contains a good deal of black slate; but it is quite massive and causes ripples in the Susquehanna river. Going north to Chapman, the road ascends geologically into higher measure passing over the upper Hamilton and the Genessee divisions, the dip keeping nearly uniform until the synclinal is met with ata small creek beyond the blacksmith shop and brick hotel with southeast dips of 60°.

Through the central portion of the township the upper portion of No. VIII is frequently seen in individual exposures, Going up the first road below Port Trevorton, gray sandstone and shale are seen dipping S. 25° E. 60°, not far north of the synclinal between Port Trevorton and Chapman. There are many exposures of shales going up to the school-house, a short distance south of which the Port Trevorton axis is developed on north and south dips of 15°.

The junction of No. VIII and No. IX was imperfectly seen on this road just before reaching Stahl’s saw-mill. The same formations come together on the north side of the basin near the Lutheran church, where the dip is about 20° E. S. E.

The Chemung shales and sandstones occupy a strip of country to the north, well exposed at J. Fishers on a southeast dip of 35°, and extend north along the river to within 300 yards of Penns creek.

Neither Oriskany nor Lower Helderberg rocks are exposed in place, being largely eroded by the junction of the creek and the river; but making an anticlinal ridge further west in Juniata county.