Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/356

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328 F³.
E. V. d’Invilliers, 1889.

anticlinal, They are but slightly developed and all present a rather ordinary stone and are all near the forks of the road to East Salem on the Gingerich place.

The Landis quarry, still further east, is much more extensive; but it too was to a large extent dismantled, and was not in operation, It is open immediately on the arch of the south anticlinal of the Lost Creek ridge with dips of 10° to 15° northwest and 40° southeast. About 40′ of very good dark blue limestone has been developed here in an opening 100′ long. It is not all first-class stone, much of it apparently being quite siliceous; still it is better than other openings in this same ridge.

A short distance further east the limestone is completely overlaid by the Oriskany chert, which creates a knobby ridge extending nearly one-half mile further before it subsides with the anticlinal under the Marcellus black slates.

On the road from the Landis quarry, northward to McAllisterville, the north leg of this anticlinal carries a very faintly defined band of yellow and white chert rock (No. VII) on its north flank, beyond which the road passes into a narrow synclinal valley of Marcellus black slate which extends westward about one-half mile before it becomes entirely enclosed by the junction of the two Oriskany sandstone outcrops. This makes another dome-shaped hill, supported further west by limestone not opened.

West of Kaufman’s the No. VII chert band is well exposed at the first bend of the road ; also the Marcellus slate No. VIII in a road cut, dipping S. 60° E. 50°, and about 25′ thick, Still further north, descending the flank of the ridge, the Lewistown series is exposed in a narrow ravine dipping 50° southeast and from 50′ to 70′ in thickness.

The narrow valley at the base of this ridge and between it and the main hill south of McAllisterville is an anticlinal of upper Salina rocks, Which are here very calcareous and have been opened at the base of the south flank of the main ridge west of Bashour’s brick house, dipping northwest 30°–40°.

The Samuel Lennart quarry is the first opening east of McAllisterville, on the north flank of Flintstone ridge. It