Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/308

280 F³. The second synclinal, known as the Ross Ore-Bank basin, contains a much wider strip of the Marcellus slates No. VIII, and is the westward prolongation of the Dry or Squaw Hollow synclinal of Granville township. The Oriskany sandstone in the south lip of this basin does not seem to be quite so thick or as massive as in the first synclinal, although both lips of the basin assist in making high parallel ridges, between which the softer No. VIII slates have been eroded. The anticlinal to the north of this is still stronger than the first axis, and elevates upon its bank a still more extended section of the upper Salina marls and shales, dipping about 60° southwards and 80° northwards.

The third synclinal is known as the Dull and Bradley Ore-Bank basin, from the extensive mines worked in it a short distance east from the line of section. This basin shows a very limited thickness of the Marcellus slates, if, indeed, it contains any at all. North of this ridge the Ferguson valley ore-ridge anticlinal has so far subsided as to bury along the line of the section both the Ore sandstone and the lower Salina rocks, and shows only the top members of the upper Salina lime shales Vc.

The fourth synclinal shows first only a narrow basin of the Lewistown limestone rocks with converging dips of about 50°, but in less than one-half a mile westward it deepens sufficiently to receive the Oriskany sandstone and (near the Wayne township line) a narrow belt of the Marcellus slates.

Kansas valley, to the north of this ridge, is a monoclinal with dips of about 50° to the southeast, showing successively lower measures approaching the flank of Jack’s mountain.

The Ferguson valley ore ridge maintains its character of a double anticlinal for nearly 3 miles into Oliver township, so that for nearly this distance there are 4 outcrops of the Ore sandstone and the Sand vein in this ridge in addition to the usual outcrop along the main mountain. The north