Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/99

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No. V, in Mifflin and Juniata.
F³. 71

becomes dimpled, and for the next 5 miles shows four outcrops of the Ore sandstone, in two parallel anticlinals, separated by a narrow synclinal. Throughout the entire ridge, frequent ravines cut through the Ore sandstone and form good opportunities for reaching the ore beds by drifts driven east and west along the line of strike. The dips are of medium strength, 30° to 40°, and the ore of the Sand Vein is largely a soft fossil above drainage level, varying from 12″ to 18″ in thickness including the “Jack” or impure ore shale at the bottom.

At Graham’s bank 3½ miles west of Yeagertown, the Sand Vein above the Ore sandstone is double, the upper bed being about 20″ thick, and the lower, separated by a few feet of shale, is 14″ to 18″ thick with 4″ of barren “Jack.”

The Danville bed, below the Ore sandstone was also shafted upon here on the north dip, and found to be a hard fossil about 16″ thick.

At the Philip’s bank, on the old Cuppels property, about 6 miles southwest of Yeagertown, two openings have been made on the outcrops of the central synclinal. The bed here is about 16″ thick, the north dip being about vertical and the south dip about 60°.

In the south dip of the anticlinal the same Sand Vein is from 20″ to 24″ thick, but not opened. At McKee’s ½ mile further west both dips of both anticlinals have been formerly opened on the Sand Vein. The Ore sandstone is here 15′ to 20′ thick, and the Sand rock, immediately under the ore beds about 3′ thick. The Sand Vein is 16″ to 18″ thick here.

At McCord & Rothrock’s bank, 8½ miles west of Yeagertown, the two anticlinals are sinking. The base of the ridge, containing the two anticlinals is nearly half a mile wide. The lower Clinton shales, decomposing into a yellow clay at the surface, form the crest of the south anticlinal, and the Ore sandstone the crest of the north axis, which therefore subsides less rapidly than its south one, The ore bed here is 14″ thick, and the Sand rock is quite ferruginous. The Ore sandstone is from 20′ to 25′ thick