Page:History of Richland County, Ohio.djvu/186

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��HISTORY OF RICHLAND COUNTY

��abundant. Northward from this locality, on the road toward Mansfield, the hills rise through the olive shales of the Waverly to the height of 350 feet above the base of this quarry. The character of the rock is well shown in the hills ; is a yellow, fine-grained, shelly sandstone, and valueless as a quarry rock. Approaching Mans- field, it becomes coarser, more massive, and more highly colored with iron, and finally passes into a coarse, massive sand-rock, evident- ly the Waverly conglomerate, the top of which is 145 feet above the base of the quarry at Bell- ville. Ninety feet below this, in the bed of a stream, alternate layers of argillaceous and sandy shales are exposed.

The top of the quarry east from Mansfield is twenty feet below the top of this coarse sand- rock, and is a continuation of it, the town rest- ing upon this formation, which crops out on all sides of it. About sixty feet of the rock is here exposed. It is all much broken ; the upper thirty feet in thin layers, the lower thirty feet in layers of from one to six feet thick. Much of the rock is beautifully colored in waved bands and lines of black, yellow and red, as delicately shaded as the best artificial gi-ain- ing of wood. Very beautiful specimens can be obtained, and if it were harder it would make a very ornamental building stone. It dresses smoothly and endures exposure well, but is soft and easily worn away by abrasion.

On Brushy Fork, near Millsborough, about six miles west of Mansfield, and thirty-five feet above the Mansfield quarry, is the outcrop of the same rock, of which the following is a sec- tion : j,,,t No. 1. Coarse, shaly sandstone in broken layers. 12 No. 2. Ferruginous sandstone, with waved lines

of stratification 6 to 10

No. 3. Coarse, massive sandstone, with irregular

veins of iron 6

No. 4. Shelly Sandstone, 8

No. 5. Blue argillaceous shale, with bands of

hard, fine-grained sandstone, to bottom

of exposure

��The upper members are the thinning-out of the Mansfield rock, the equivalent of the Wav- erly conglomerate. On the opposite side of the stream, the yellow sand-rock is about thir- tj'-five feet thick, coarse, ferruginous, with black iron streaks. There are about ten inches of light-colored and firm stone. All the rest, so far as exposed, is worthless for building pur- poses.

The rock at the bottom is blue argillaceous shale, with hard, blue bands, bearing a close resemblance to the Erie shales ; no fossils dis- covered. In places, interstratified between the layers of the yellow sandstone, there is a layer of ten to twelve inches of white argillaceous shale, which, when disintegrated, bears a close resemblance to the fire-clays of the coal meas- ures. Outcrops of this rock are to be seen northward, near Lexington, and between Lex- ington and Bellville, containing quartz pebbles and many nodules of soft iron ore ; all the rock, in thin layers, extending to the tops of the hills, making the connection complete between the Mansfield and Bellville quarries. The Clear Fork here flows through a broad alluvial valley, bordered with heavy hills of modified drift, generally sandy, in places composed of coarse, water-worn pebbles and bowlders, the stream occupying the raised bed of the old channel, which passes west of Mansfield, and connects the waters of the lake with the Ohio.

Between the top of the argillaceous and sil- iceous shales, which very generally underlie the horizon of the Waverly conglomerate, there is ah interval of something over three hundred feet, before the Berea, which is quarried in the extreme northwest corner of the county, is reached. The northern part of the county is comparatively level, the surface deeply covered with unmodified clay drift, except along the lines of ancient erosion, where the sand-ridges equally mark the geological structure. Hence there are very few rock exposures, and these so

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