Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/282

From Wikisource
Jump to navigation Jump to search
This page has been proofread, but needs to be validated.
254 F³.
E. V. d’Invilliers, 1889.

These analyses are inserted here merely to give an idea of the character of the ore formerly found at this point, for it is claimed that there still exists a very large body of ore here; and being so advantageously situated for working there does not seem to be any good reason why an active operation should not be maintained here if it would pay to work such fossil ore beds of equal thickness anywhere else in the county.

Some prospecting was once done south of Midland station about 4 miles east of Lewistown on the Shade mountain outcrop of the Ore sandstone, which proved a good soft fossil ore corresponding to the Sand Vein dipping about 40°, northwest, and from 16″ to 18″ thick. No ore however was shipped from here.

The Danville ore beds were also said to have been opened “16 inches thick and of good quality.” West of this point to the Juniata no developments have ever been made, although Jack’s creek in gapping the Ore sandstone ridge should offer an excellent opportunity for opening the fossil ore beds on their end if they existed here of sufficient thickness and quality.

Above or inside of the two opposing outcrops of the Ore sandstone there is a varying width of the upper Clinton and lower Salina (Bloomsburg) shales, which make a moderately good farm land and are largely cultivated; but the farm lands par excellence through this valley are those underlaid by the next highest series of rocks, the upper Salina shales and marls Vc, which outcrop along the base of the lime- stone ridges on either side of the valley as well as between two of these ridges to the east of Logan.

In many parts of Mifflin and Juniata, these upper calcareous shales are frequently interstratified with bands of red shale so like the Bloomsburg red shales of the lower Salina group as to make it difficult to subdivide the two groups on the map by any intelligent system of coloring. In Union and Snyder county the Bloomsburg red shales make a distinct horizon wherever they occur, as there are barely any red bands occurring in the upper Salina rocks between the Bloomsburg shale and the Lewistown limestone.