Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/17

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Letter of Transmittal.
F³. xiii

have dug into certain black slates which range along the edge of Kishicoquillis valley inside Logan gap, in hope of finding a coal bed; in hope that the black slate at the surface will turn into coal if followed down beneath the surface. Such hopes are silly. There are also black slate beds in the Marcellus formation and in the Genesee formation; and sometimes these black slates have a good deal of old animal fat in them, which time has changed and hardened into asphalt, so that specimens put into a blacksmith’s fire will fry and flame for a few minutes. But no one has ever seen or heard of a coal bed in these formations. There is not a ton of real coal in the four counties. All the formations of the district are much older than the coal measures, and were deposited before the first coal bed was made. The oldest coal bed is that in Perry county, and that is good for nothing.

Note on the River Drainage.—The two great rivers of this district, the Susquehanna and the Juniata, have had a curiously different history. The Juniata river has had the same water basin from its birth, that is from the elevation of the coal-measure continent out of the sea at the close of the Permo-carboniferous age. The West Branch of the Susquehanna has considerably and the East Branch has greatly enlarged its water basin since the Ice age.

The Terminal moraine (see Report Z) running across Luzerne, Columbia, Lycoming, Potter and McKean counties, across the Susquehanna waters, running far north of the whole Juniata water basin, interfered with none of its branches, and never furnished any glacial sand, gravel or bowlders to its water courses. In this respect the Juniata resembles the Schuylkill river, in whose alluvians no northern drift material is noticeable. The Susquehanna yallies, on the contrary, like the Delaware valley (and for the same reason), are full of secondary northern drift deposits, obtained since the Ice age from the stuff brought southward by the ice as far as the line of the Terminal moraine.

The West Branch Susquehanna flowing past Union county was always a noble river, for it always had Muncy, Loyalsock and Lycoming creeks pouring their waters into it