Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/366

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338 F³.
E. V. d’Invilliers, 1889.

brown shales on a 60° dip. No exposure of the sandstone in the north side of this anticlinal was noted.

Westward to the river the Slenderdale ridge is made up of the Clinton rocks occurring above the Ore sandstone measures; but they seem to be quite sandy and generally much more massive than elsewhere in this district. It may be too that the Ore sandstone extends further west than as shown on the map; but there are no gaps in this ridge until Horning run swings around its western extremity only a short distance from the river and the opportunities therefore for noting its presence were not very favorable. They likewise contain several thin beds of limestone, and in the gap of Horning run these olive and lime-shales make the crest of a perfectly preserved anticlinal with dips of 60° southeast and 10° northwest.

Further south down the ran the upper Salina lime shales show upon a southeast dip of 40° with some reddish shale, possibly the Bloomsburg measures, between these two outcrops dipping southeast 50°. The synclinal passes about through the mill and holds a very small amount of the lower members of the Lewistown limestone, rather impure and shaly in places, but containing some good beds.

To the east this basin rises steadily, showing everywhere a narrow fold with dips of about 40° southeast and 70° northwest, and passing into Fayette township it deepens again to receive the first limestone ridge south of McAllisterville. This is best known as the Licking Creek synclinal.

Crossing Slenderdale ridge trom Suloff’s gap only the olive and brown Clinton slates are seen until along the south base of the ridge, the Bloomsburg red shales show near Crum’s place on a 30° southeast dip and can be traced as a narrow band hugging the foot of Slenderdale ridge into Fayette township.

On the south side of the Licking Creek valley there is another corresponding band of the same red rocks showing especially well between Thomas’ place and the schoolhouse and dipping steeply northwest. Tt is between these two outcrops that the upper Salina lime shale occurs, making, as usual, an excellent farming soil belt through the township from one-half to 1½ miles wide.