Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/367

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39.Fermanagh in Juniata.
F³. 339

Immediately north of Mifflintown, along the canal and pike, the same upper Salina lime shales outcrop with southeast dips of 30° to 40° succeeded northward near the first road leading east by a considerable outcrop of the Bloomsburg red shales and thin bedded sandstones, creating an excellent exposure extending along the pike for nearly 100 yards to the first lockhouse. Some Clinton olive and lean lime shales succeed, going north, and beyond the next ravine the Ore sandstone is finely exposed on the south flank of the Lost Creek ridge anticlinal about 20′ thick and dipping southeast 20°. It is quite massive and slows the same gray hard sandstone weathering brown, and which dresses so readily as to have been used in many parts of the district for building purposes, despite the fact that the iron it contains generally causes it to weather a dark brown color, and somewhat irregularly so. The effect of this weathering is to many very pleasing.

Its outcrop here creates a little terrace ridge on the flank of the main hill formed of lower Clinton measures, so that the Sand Vein ore bed would necessarily have to be sought for along the ravine, and would be largely devoid of soft fossil ore. Higher up the ravine some ore might be found, as the dip is slight and the hill increases in elevation going eastward. The Danville beds are concealed here, though they have been apparently sought for in the side of the sandridge higher up.

The Ore sandstone in the north leg of the anticlinal is concealed, and though the Bloomsburg red shale at the Cuba mill dips 60° northwest, indicating a single simple anticlinal axis, the exposures on the west side of the river along the railroad show the lower Clinton shales to be considerably twisted and folded between the two outcrops of stone.


Along the road leading east from the river on the south side of Lost creek ridge the stream practically divides the Bloomsburg red shale from the underlying upper Clinton shale.

The Ore sandstone first touches the road about a mile