Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/123

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2.Kelly Township in Union.
F³. 95

burg rocks on the north side of the anticlinal, dipping northwards at angles of 40° into the succeeding synclinal basin along the White Deer township line, which contains a strip of the upper Salina lime shales, narrowing westward for about 6 miles, where these rocks are eroded at Spruce run and the basin filled with the Bloomsburg red shales.

These Bloomsburg shales create low but distinct ridges on each side of the basin, and are excellently exposed in the north leg of the synclinal, between the forks of Little Buffalo creek at Parvin’s and Rothermel’s store, on a dip of S. 20° E. 45°. The gray lime shale valley to the south of this point is only about 250 yards wide, the Bloomsburg red shales forming its southern boundary also, dipping N. 25° W. 35°.

The gentle Milton anticlinal still further south along Little Buffalo creek, shows merely a narrow band of upper Clinton rocks, with dips of 10°, and almost immediately succeeded by a third band of the Bloomsburg red shale somewhat wider at this point than on the river, owing to the effect of the Jones mountain axis.

Exposures of the succeeding upper Salina marls and lime shales south towards Buffalo creek are exceedingly rare, but invariably show gentle southeast dips of from 10°-15°.

Buffalo creek marks the northern limit of the Lower Helderberg limestone from the month of Little Buffalo creek up stream to Hafer’s grist and saw-mill, so that all the limestone exposures here are in Buffalo township. From Little Buffalo, however, the limestone outcrops in a prominent ridge running a little north of east, and reaching the river about 1¾ miles above Lewisburg.

Sections further east along the two north and south roads crossing this ridge to Buffalo creek show the Marcellus and Hamilton rocks occupying the broad inside sloping terrace of the ridge on southeast dips of about 10°.

Both the Oriskany and Lower Helderberg rocks are poorly exposed, owing to the absence of ravines cutting the ridge and the low dip of the rocks. The limestone rocks are nowhere quarried in this township.