Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/77

Rh of McVeytown, and have formerly furnished a great deal of ore from the Marcellus bed. From 80′ to 100′ of black slate intervenes here between the Oriskany sandstone and the lowest ore-bed, which is immediately underlaid by limestone. The ore-bed is from 2½′ to 8′ thick, overlaid by black slate.

West of MceVeytown the synclinal and anticlinal crimples flatten out into one broad basin along the Juniata west of Newton Hamilton. Here the Portage flags are excellently exposed in the railroad cuts north of Newton Hamilton, lying perfectly flat in the trough of the synclinal. The whole group here is about 2000′ thick.

The Marcellus limestone has been quarried on the river just east of Newton Hamilton, at the Norton quarry, where it is 40′ thick and shows a hard gray crystalline and siliceous limestone in flat beds 2′ to 4′ thick, almost directly in contact with the Oriskany No. VII, which shows plainly on the river. The same limestone has been quarried and burned at several other points here, showing the same characteristics.

In Juniata county the No. VIII rocks west of the river are confined to the immediate valley of the Tuscarora, and east of the river occupy the synclinal made by successive rolls of the Oriskany sandstone spreading out along Mahantango creek to the Susquehanna. Several anticlinal axes, originating in the eastern belt 5 or 6 miles wide, increase in strength westward, and as they pass out into lower formations they throw the Devonian rocks into a series of folds and narrow triangular basins, which terminate westward.

Along the Susquehanna these rocks partake largely of the character displayed on both sides of the Shade mountain anticlinal at Selinsgrove; except that both the Marcellus and Hamilton groups thin somewhat. There is very little limestone in the series.

The country is generally one of poor soils, and topographically consists of a series of long narrow ridges