Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/390

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362 F³.
E. V. d’Invilliers, 1889.

the upper Salina measures south of the limestone valley are again exposed with somewhat irregular dips as along the river, but with a general northwest dip of about 40°, away from the Academia anticlinal to the south.

The Bloomsburg red shales, here again somewhat mottled and indistinct, come in just before reaching the first side road, and with the intercalated lime shale beds cannot be less than 150′ thick, nor more than 250′ vertically above the Sand Vein fossil ore bed, opened in the field on the east side of the creek and the road.

The Ore sandstone crops out just at the dam above Hahn’s mill and is again well exposed in the ridge on the west side of the creek, dipping N. 45° W. 40°. Some little work of exploration has here been done on the Burchfield property, on both the Sand Vein bed above the Ore sandstone and the Danville (“Ginger” or “Mud Vein”) bed, beneath the sand rock. A drift has been driven on the latter bed about 100′ above water level. No information could be ascertained concerning the quality or thickness of the bed and the drift was too badly fallen in to permit of any personal examination, but if of any economical value at all, there would be a most excellent opportunity for mining with the security of long stopes and probably much soft fossil ore.

Good exposures of the underlying Clinton shales occur at Hahn’s mill, a little further down the creek, south of which the dips flatten greatly and finally make a broad anticlinal arch. The exact position of the axis is obscured here by erosion, but passes about one-half a mile below the mill.

The Iron sandstone is not exposed on the arch and is probably not elevated at any point east of the creek. There are no other exposures until approaching the McCullough Mill dam, where gray and red slates underlying the Ore sandstone dip about 30° S. E. The Ore sandstone next appears at the turn of the road near the upper end of the Port Royal dam, dipping S. 42° E. 30°, about 12′ thick and somewhat shaly. Ferriferous shales occur above and below it, but without visible ore.

The Bloomsburg shales follow further down the creek and