Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/176

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148 F³.
E. V. d’Invilliers, 1889.

burg; but it seems only to have furnished a little building stone for village use and shows generally hard siliceous beds 15′ or 20′ thick on a southern dip of 40°,

A thin mantle of Oriskany shale and chert is seen along the crest and south flank of this ridge; but the formation nowhere shows any massive beds and scarcely any sandstone at all.


The southern two-thirds of the township is entirely occupied by the Devonian and Catskill ridges, which show to about the same extent as they do in Jackson township, except in the western portion, where the basin has so flattened out while rising westward as to present flatter dips as well as a more even erosion and regular topography.

The upper Marcellus black slates show at the bend of the Middleburg road, a mile south of Centerville, where they have been slightly quarried, presumably for road purposes. They are very much twisted and the dip is therefore obscure, but not less than 50° towards the southeast. In the next ¼ of a mile south from George Young’s there are several more or less satisfactory exposures of Hamilton shales and thin sandstone on dips of 45° and 40°, decreasing as the axis of the synclinal is approached.

At S. Bruner’s, approaching the forks of the road, the Chemung rocks show an exposure of sandstone and shale, dipping only 30°, and to the south of it the transition members between No. VIII and No. IX inclined but 20° to the southeast.

The Methodist Episcopal frame church and cemetery on the crest of the ridge, an eighth of a mile north of Franklin township line, closely marks the position of a synclinal axis with the Catskill No. IX rocks occupying a belt in its trough, about ½ a mile wide, showing converging dips of 15°–20°. The precise limits of this formation are hard to determine, for the red bands are largely mixed with olive ones, weathering yellow and with layers of greenish-gray sandstone, hard to distinguish in the absence of fossils from the Chemung type of rocks.