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CHAPTER VI.

A SYNOPSIS OF THE GEOLOGY OF OHIO.

THE geology of Ohio, though not differing materially from that of the adjoining States, has some very marked features not found elsewhere in the Mississippi Valley, and as some of its peculiarities extend into Wayne county, it will be proper to briefly notice the geology of the State, in order that the reader may the better understand that of the county.

The location of this State is peculiar ; being in the upper end of the Mississippi Valley, and bounded on the north by Lake Erie and the ridges of Michigan, and on the south by the Ohio river, it has ever been in a position to be wrought upon by water from the north, as it has been in several eras.

One of the most peculiar features of the geology of this State is the Cincinnati anticlinal, a description of which is furnished by Professors Newberry and Orton,* the latter having made a complete and full survey and report of the same.

The existence of this uplift had been long known to geologists, but its true character was wholly unknown until Professors Newberry and Orton made their report upon its structure and the probable era of its elevation. Drs. Locke and Hildreth had given opinions concerning the uplift, and Professor Spofford had shown its existence in Tennessee.

The Cincinnati Arch consists of an uplift of the Lower Silurian, with all imposed strata then existing, in the form of an arch, the center and summit being east of Cincinnati. The arch is bent up

* Geological Survey of Ohio, vol. I, page 97.

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in the shape of a bow, the southern end extending to the south line of the State of Tennessee, and the northern end passing under Lake Erie between Sandusky and Toledo. From the southern line of Tennessee the anticlinal extends a little east of north through Nashville, the Blue Grass regions of Kentucky, and through Ohio to its terminus in Lake Erie. Professor Orton, by actual survey, located the apex of the arch at Bethel, in Clermont county, east of Cincinnati. The blue limestone about Cincinnati represents the highest part of the arch in this State, and the blue limestone of the Blue Grass regions of Kentucky represents its highest part in that State. From the pivotal point, or apex, the dip is south on the incline of the arch, and from the apex north on the incline to the lake. On the eastern side the strata dips south of east under the coal measure of the Alleghenies, and westward the strata dips under the coal measures of Indiana and Illinois.

The line of uplift of the arch is parallel with the folds of the rocks of the Alleghenies, and as observed by James A. Dana, stretched south-westward into Kentucky and Tennessee, and dating " from the beginning of the upper Silurian, probably divided the great interior marshes about the Upper Ohio regions from that of the lower."*

The top of the arch has suffered much from erosion, the southern extension near the Ohio river much the greatest, yet the altitude is still greater there than at the lake or where exposed in its vicinity.

From present indications, the upheaval of the arch at first constituted a low mountain, and perhaps divided the waters of the Mississippi until the whole valley was elevated. The highest part of the arch, at Bethel, is 100 feet above the rock surface at Cincinnati. Before the uplift of the arch, all the Cincinnati group rested upon it, showing that the entire lower Silurian strata had been constructed and in place before the upheaval. The strata on either side of the central line of the arch, from the apex to the lake, very clearly shows the position of the arch where the various beds of

* Dana's Manual of Geology, page 391

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strata accumulated, as the strike on the east side is nearly north and south from the lake to the Ohio river ; but on tbe western side it is nearly north-east and south-west. The continuation of these lines, in the direction they bear, would bring them in conjunction near the north shore of Lake Erie.

Professor Orton has given a number of measurements of altitude of the Cincinnati group of rocks, connected with the anticlinal, which tend to show the original condition of the arch in the regions of its apex and the dip of its strata. He reports the highest point of contact between the Cincinnati and the Clinton groups near Lebanon, at 441 feet above Lake Erie, from which point the dip for the distance of thirty-five miles northerly is at the rate of about four feet to the mile. At the northern part of the State the rocks of the Cincinnati group are not exposed, and hence the level of the surface has not been ascertained in that locality, nor the dip of the strata composing the arch. But at the mouth of the Vermillion river, at Sandusky, Toledo, Striker and White House, borings have been made at points from 20 to 30 miles from the summit of the arch at the north, by which the blue limestone strata has been shown to be about 800 feet below the level of Lake Erie. The Niagara and Helderberg rocks overlie the Cincinnati group, and are exposed along the line of the anticlinal, by which Professor Orton was enabled to ascertain the northern slope of the crest.* He found the highest exposure of the Niagara strata between the waters of the Little Miami and the Scioto rivers, the surface being 557 feet above Lake Erie. The east and west dip of the rocks forming the arch is much more rapid than to the north, and at the rate of the dip, if the lines were extended, would form an arch a thousand feet in hight.

The dip of the rocks which flank the arch on the east is more rapid than on the west. This fact has been ascertained by the position of the strata, especially the Huron shale, which shows a a dip of 35 feet to the mile, according to Professor Orton ; and Dr. Locke reported the dip of the blue limestone at 37 feet 4

* I Vol. Geological Survey of Ohio, page 98.

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inches per mile. At Bellefontaine, Logan county, the base of the Huron shale is only 65 feet above Lake Erie, making a dip of 605 feet, being 12 feet to the mile. The dip eastward from Bellefontaine to Delaware, on an air line 36 miles east, is 402 feet, which is about it feet to the mile.

Comparing the elevation of the surface of the Cincinnati group, in the south-western part of the State, with the level of the same geological horizon at Columbus, the following result is shown : At Lebanon the surface of the blue limestone is 441 feet above Lake Erie ; at Columbus the surface is 721 feet below the lake level, thus showing a dip in a north-east direction of 1,167 feet in a distance of about seventy miles, being about 16.6 feet to the mile.*

The elevation of the Cincinnati arch was slow and gradual, the strata of which, not being materially affected, except elevated in the form of an arch, was simply a gentle flexure (as remarked by Professor Orton) of the earth's crust. It was, doubtless, one of the earliest of the great system of folds or wrinkles so wonderfully manifested in the Appalachian mountain system. No definite date can be fixed showing the age when the first upward movement of this arch took place, or when it was left at rest. But it was certainly elevated in Southern Ohio, "above the sea at the end of the Blue Limestone period, early in the Clinton epoch. +

The exposed rocks of the Silurian system found in the Cincinnati arch are the Cincinnati group, the equivalents of the Hudson and Utica shale, of New York, which are also exposed in the valley of the Ohio at Cincinnati, where about S00 feet in vertical thickness appear in cliffs.

From the survey of the arch, and observations made by Professor Orton, it is quite manifest that the Lebanon beds, the topmost portion of the Cincinnati group, once stretched over its entire breadth, and that the entire system was formed and rested in a horizontal position before the first oscillation or upward movement of the arch commenced.

* Geological Survey of Ohio, vol. I, p. 100. + Geological Survey of Ohio, vol. I, p. 417.

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The rocks covering the arch, when it was elevated to its present position, to some extent have disappeared by erosion. As far north as Dayton the whole crown of the arch is occupied by the outcrop of the Cincinnati group, and so deeply eroded as to form the valleys of the two Miamis. Around the margin of the blue .limestone extends a broad belt of the Clinton and Niagara groups. "In Clark, Champaign, Darke, Shelby and Mercer counties the Niagara is its surface rock over the entire breadth of the anticlinal."* The corniferous limestone flanks the side of the arch from Pickaway county to Sandusky, and from Sylvania up the Maumee to Paulding. The deposition of the strata flanking and overlying the arch, proves very clearly its elevation took place between the eras of the formation of the lower and upper Silurian systems, long prior to the elevation of the Appalachian system ; and that the arch stood forth as an island long before the submergence of the Appalachian chain, is more than probable.

On the eastern side of the arch the dip of the strata composing it is not always regular, its uniformity being interrupted by subordinate folds, though the dip, by successive steps, passes beneath the trough of the Allegheny coal field, the axis of which is beyond the eastern border of this State. At the east line of the State the strata of the eastern declivity of the arch is buried 2,000 feet beneath the surface. East of the State line the strata, the lowest exposed in Ohio, as well as those systems underlying them, crop out on the flanks and summits of the Alleghenies.

The dip of the strata north and south along the arch is now a subject of much interest, since the true character of the anticlinal has been made known by Professors Newberry and Orton in their geological survey of this State. The dip northward from the Ohio river to the lake is about 1,000 feet, and while the surface of the Cincinnati group in Highland county is 500 feet above Lake Erie, on the lake shore it is 400 feet below the lake level.

In the eastern half of the State the dip north and south is equally interesting. At Little Mountain, Lake county, the carbon-

* Geological Survey of Ohio, vol. I, p. 102.

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iferous conglomerate is 600 feet above Lake Erie, while at Marietta it is over 600 feet below the lake level, showing a southward dip of over 12,000 feet. This difference in the north and south dip of the eastern and western portions of the State is owing, in great extent, to the fact that the Cincinnati arch falls off rapidly toward the north, terminating in the low country north of Lake Erie. If the eroded portion of the arch at its axis could now be measured, the dip from the Ohio to the lake would far exceed 1,000 feet.

The eroded surface of the Cincinnati arch in the blue limestone regions of Kentucky is 130 miles, where much of the crown has been swept away ; northward, in Ohio, it is much narrowed, not being over 90 miles wide on a straight line east and west.

The surface of the country does not, as a general rule, give evidence of the thickness, nor, indeed, of the system, of the underlying strata. Deep boring is the only sure method to measure the thickness and learn the kinds of strata beneath the surface, and by means of which much light has been reflected as regards the geological structure of Ohio. In the well bored at Toledo, the red shale was reached at the depth of S00 feet. This well passed through 100 feet of drift, through the upper Silurian limestone, water lime, Niagara and Clinton rocks.

The crown of the arch is at Genoa, Elmore and Washington, 15 and 20 miles in a south-easterly direction from Toledo. It is there covered by the Niagara, which is about 50 feet above the lake level.

The deep boring at the State House well at Columbus shows the character of the strata in that part of Ohio for the depth of 2,570 feet. The first stratum passed through was clay, sand and gravel, 123 feet thick ; the next stratum was black shale, 15 feet thick ; the next a gray limestone rock, with chert 138 feet thick. Water was struck in this strata, at 150 feet from the surface, which washed away the borings to the depth of 242 feet. Sulphur water was found at 180 feet. Immediately below this formation was a very gritty rock, two feet thick, which occupied two days' drilling to pass through. Water from this point rose in the tube five feet. Below this rock, and upon which it rested, was a limestone strata

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486 feet in thickness. The limestone was of light color and sandy above, but darker and argillaceous below. Salt water was reached in this strata at 675 feet. The next strata below was red, brown and gray shales and marls, 162 feet thick, the borings of which were impregnated with salt. Underlying the red, brown and gray shales and marls were blue and greenish calcareous shales 1,058 feet in thickness, the borings impregnated with salt. The next strata below was a light colored magnesian limestone 475 feet in thickness; water in the tube of saline character. Below this strata was a whitish calcareous sandstone 316 feet thick. The next strata below, at the bottom of the well, was a sand rock. The total depth of the well was 2,775 feet, 4 inches, but no register was kept of the borings below 2,570 feet, they having been swept away by water.

In Vol. I, page 114, of the Geological Survey of Ohio, Professor J. S. Newberry has in a very clear manner given the character and kind of strata through which the auger passed at the State House well in a geological section, a copy of which is here given :

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LOWER SILURIAN.

This system of rocks rests upon those of the Eozoic period, the lower member, Potsdam sandstone, resting upon the broken and upturned edges of the Laurentian, as represented in section

Fig. 1.

The rocks composing the lower Silurian in this State are the Potsdam sandstone, Calcifereous sand rock, Chazy limestone, Trenton group, and Hudson group.

Potsdam Sandstone.

This rock is a white, calcareous sandstone, and though not visible in any outcrop in Ohio, was reached by the auger in the deep boring of the State House well, at Columbus.

Calciferous Sand Rock.

This system of strata, when in place, rests immediately upon the Potsdam rock. In Ohio it was passed through in the sinking of the State House well. It is the Magnesian limestone of Missouri.

Trenton Group.

Resting on the calciferous sand rock are the Trenton series, consisting of the Trenton limestone, Black river and Chazy limestone. Upon the Trenton repose the Hudson group, consisting of the Hudson and Utica shales. The Hudson group in this State is a mixture of calcareous and argillaceous sediments. This formation, with the Utica shale, and a portion at least of the Trenton limestone, are the lowest exposed rocks m the State, and the Cincinnati limestone, and the well known blue limestone, which are usually considered as the equivalents of the Hudson and Utica shales, but containing so many of the Trenton fossils, must, according to Prof. Newberry,* in part at least, be considered of the Trenton group. These ancient rocks were brought to the surface by the upheaval of the Cincinnati arch ; and by the wearing

* I Vol. Geological Survey of Ohio, page 6o.

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down of the valley of the Ohio by the river, B00 feet in vertical thickness are exposed to view in the cliffs. About 1,200 feet of the Cincinnati group were passed through in boring the artesian well at the State House. This group of strata, it has been claimed, contains a large amount of bituminous matter, and is the first and lowest system of rocks containing petroleum, or carbon oil.

UPPER SILURIAN.

This system of strata has been very clearly defined by the New York geologists. The strata there consists of the Oneida conglomerate, Medina sandstone, the Clinton, Niagara, Salina, and Helderberg groups.

Oneida Conglomerate.

This is the lowest member of the upper Silurian system, and rests upon the Hudson formation in the State of New York, where it attains a thickness of about one hundred feet. It passes from there in a narrow belt through Pennsylvania and Virginia, attaining a thickness in the Alleghenies of from 500 to 700 feet. It is composed of very coarse materials and sand. Thus far this formation has not been found in Ohio, except where it runs into and forms a part of the

Medina Sandstone.

This formation, in the State of New York, attains a thickness of from 300 to 400 feet. It is composed of sandstones and shales, the prevailing color of which is red. It thins out toward the west and is found in Northern Ohio in boring for oil, but no well defined outcrop has been as yet discovered in the State.

Clinton Group.

This formation consists of shales and sandstones, in which is a stratum of iron ore from 2 to 10 feet in thickness, called " fossil ore," a granular red hematite, which is traced through from Dodge

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county, Wisconsin, to the State of New York, from thence southward through Pennsylvania, Virginia, Tennessee, Georgia and Alabama. This group is represented in Ohio by a limestone formation, from 15 to 50 feet in thickness, the outcrop of which " follows the sinuous line of junction of the Lower and Upper Silurian, in the country about Cincinnati." Credit is due Professor Orton for the discovery of the fossil iron ore in this stratum in Adams

county.

Niagara Group.

Overlying the Clinton formation is the Niagara group, which includes the celebrated limestone rock, over which the Niagara river pours its floods at the cataract. It consists of two sections, one of limestone, the other of shale, of about equal proportions, each at the falls being about 80 feet in vertical thickness. It is an extensive formation, and conspicuous in most of the Western States. It underlies Chicago, extends into Michigan, Canada, New York and Tennessee, and it is a prominent formation of Ohio, especially so in connection with the Cincinnati anticlinal.

Salina Group.

This formation derives the name Salina from the salt found in it, so extensively manufactured at Syracuse, New York. It is not so universal as the Niagara, upon which it reposes. It is composed of marls and shales, with some impure limestone and gypsum. In Northern Ohio it rests immediately on the Niagara, and contains the gypsum of Sandusky.*

Helderberg Group.

This group is so named on account of its forming a considerable portion of the Helderberg mountain south of Albany, New York, where it attains a thickness of 200 feet. It is chiefly made up of earthy limestones, though in several distinct strata. Its

* Geological Survey of Ohio, vol. 1, page 63.

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lower member is celebrated as being a water-line formation, and which is quite extensive in Ohio, where it is a surface rock, and has beeome a source of much profit to those engaged in its commerce, especially in Sandusky county, where it is extensively worked and attains a thickness of 100 feet. This is the strata from whence comes the hydraulic cement, so largely used. The water-line group does not outcrop in Eastern Ohio, but seems to be confined to the western and southern portions of the State. This formation extends from New York into New Jersey, Pennsylvania, Maryland and Virginia, where it is said to attain a thickness of 300 feet, on the Potomac river. It continues westward from Ohio into Indiana and comes out to view in the State of Illinois.

DEVONIAN SYSTEM.

The rocks of this system are composed of quartzose sandstones, marls and conglomerates ; and in the countries of Europe where heavily charged with iron, or, rather, peroxide of iron, it imparts to them a dull red color, and hence are called "old red sandstone," which Hugh Miller has made famous by the discovery of fossil fishes in them, The name is derived from that of Devonshire, England, where this strata is very extensive. The formation is exposed in South Wales, England and Scotland, where they have long been known as the " old red sandstone," In Devonshire and Cornwall the rocks are slates and limestone.*

The Devonian formations of North America are of vast extent, estimated at 15,000 feet in vertical thickness. The rocks of the Devonian age underlie a large part of New York, Pennsylvania, Virginia, New England, Maine, West Virginia and Ohio, and are extensive in Canada, Nova Scotia and New Brunswick, and have been recently discovered in Utah and Nevada.

The Oriskany Sandstone.

This formation, formerly considered as belonging to the upper

* I Vol., Wonders of Geology, page 204.

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Silurian, is now classed with the Devonian series. It is not well defined in this State, though its equivalent is considered to be existing in a number of localities. It is represented in Sandusky county, also at West Liberty, in Logan county, on the peninsula west of Marblehead, in Ottawa, and at Sylvania, in Lucas county, and in many other localities, ranging from three to ten feet in thickness. The rock is soft and white, and capable of being used in the manufacture of glass. Considerable quantities of this stone have been taken from the Sylvania bed, transported to Pittsburg, and successfully used in the manufacture of glass.

Corniferous Limestone.

The corniferous limestone is separated into the upper and lower, and is exposed in the quarries at Bellevue and in other places. The upper is buff colored, coarse grained magnesian limestone, and containing beds of chert. The lower is a bluish gray, crystalline hard stone, usually fossiliferous—strikingly so in some instances. The outcrops of this formation form two separate belts, one on each side of the Cincinnati axis. The eastern belt crosses the State from the lake to the Ohio river. It also extends to Columbus, where it is extensively quarried, and of which the State House is constructed.

Hamilton Group.

This group consists of the Marcellus shale, the Hamilton proper and the Genesee shale, with the Moscow shale, the Tully and encrinal limestones, and in New York State attains the thickness of more than 1,000 feet, but greatly diminishes to the west. In Central Ohio the bed overlying the corniferous, and corresponding with those above mentioned, is the Huron shale, a bituminous mass about 300 feet in thickness. Resting upon this formation is the Waverly group, consisting of fine-grained sandstones and shales 500 feet in thickness ; and upon the Waverly reposes the carboniferous conglomerate.

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Portage and Chemung Group.

This series of formations consist of sedimentary rocks named from localities where they exist. They are composed of shales and sandstone in the State of New York, and are 2,000 feet in thickness. The upper and coarser portions of these rocks have a thickness in Western New York and Pennsylvania from 1,000 to 1,500 feet. In Ohio the Portage and Chemung rocks form the lake shore as far west as the mouth of the Vermillion river, and are called in this State the Erie shale. The lower portion of the strata is called the Huron shale, and extends in a belt of outcrop from the mouth of the Huron river to the mouth of the Scioto, and there attains a thickness of about 330 feet. The Huron shale is known as the Black shale, and is well exposed in the banks of the Scioto and the Ohio near Portsmouth, on the Big Walnut east of Columbus, Worthington, and on the banks of the Huron. It is of a bituminous character, and doubtless the source of the oil and gases in Ohio, and supposed to supply all the oil to the wells on Oil creek, in Pennsylvania. It is noted for the fossil fishes it contains, some of them being the largest discovered.

Erie Shale.

This formation in this State is greenish and bluish argillaceous shales, and from the Pennsylvania line to Avon, the strata thins out rapidly to the west, and disappears south and west of the Vermillion river. The strata is well exposed in the cliff on the lake shore in the vicinity of Cleveland, and consists of gray and blue shale, very soft and fine, and containing veins of silvery sandstone, and masses of argillaceous iron ore.

West of Cleveland the Erie shale consists of two groups of strata, the upper being nearly T00 feet in thickness, consisting of the above described shales with thin bands of sandstone, which are used for flagging. The lower portion consists of blue and green shale, with a thin strata of iron ore. The two are seen in the cliffs on the lake shore between the Rock river and the Cuyahoga.

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CARBONIFEROUS SYSTEM.

This series of strata rests upon the Devonian system, and owing to the valuable minerals it contains, is the most noted formation in Ohio. It is the highest order of strata in ascent of the geological scale, which is owing to the missing section of strata in the State.

This system consists of three subdivisions—the coal measure above, the conglomerate in the middle, and the lower carboniferous, sub-carboniferous Waverly group below.

The lowest member of the system is the Cleveland shale, a black bituminous strata of about 54 feet in thickness at the mouth of the Cuyahoga river, but on the Vermillion river from 60 to 80 feet of the strata is exposed. At Bedford, in the gorge, it has been cut through by the stream to the depth of 21 feet. It is the lowest member of the Waverly group, and contains from 15 to 20 per cent. of bituminous matter', and is supposed to be the source of the petroleum found in Trumbull, Lorain and Medina counties.

This group consists of this shale, Bedford shale, Berea grit and Cuyahoga shale, the series being about 500 feet in thickness, though on the Ohio river it is more massive, the sandstone there being 640 feet in thickness.*

The Bedford Shale.

This shale rests upon the Cleveland, and immediately underlies the Berea grit. It is of a red color, and about 75 feet thick. It is well exposed at Elyria, in Lorain county, on the Black river, also at Amherst.

The Berea Grit.

This rock is an important member of the Waverly group. It is in two sections (the upper and lower), the former being thin layers, used for flagging ; the latter being massive, and extensively quarried and used for building purposes and for grindstones, the

*Dana's Manual of Geology, p. 295.

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celebrated Berea grindstones so popular in Wayne county being taken from these quarries. The aggregate of the layers of the upper strata is about 20 feet, and of the lower about 30 feet. This formation extends from Lake Erie south through Ohio, and underlies a large portion of the State.

It is the rock penetrated by the oil wells at Grafton, Liverpool and Mecca, and extends into the oil regions of Pennsylvania, though there it is less massive.

The Cuyahoga Shale.

This formation is the upper member of the Waverly group, and reposes on the Berea grit. It is from 150 to 250 feet in thickness, and consists of a gray argillaceous shale, with thin flag and sandstone, its outcrop defining a belt extending from Berea through to the valley of the Cuyahoga, and constituting the banks of that river southward as far as the Falls, which it forms.

Resting on the Cuyahoga shale is the lower carboniferous limestone, known as the Chester limestone, about 20 feet in thickness.

Overlying this strata is the conglomerate formation, of 100 feet in thickness, composed of pebbles, coarse sand and gravel. It is of irregular character, and follows the coal measure throughout the State.

The Coal Measure.

The coal measure is the next series of formations, and is 1,200 feet in thickness, and contains the various coal strata of the State. It is confined to the eastern portion of the State, extending from Lake Erie, east of Cleveland, down the valleys of Tuscarawas, Killbuck and Muskingum to the Ohio river, being largely developed in counties west of the Muskingum. It is a part, or an extension of the Allegheny coal fields, but owing to the uplift of the Cincinnati arch, it is confined within the limits described. With the exception of the drift, the coal measure is the highest member of the geological series of Ohio, and constitutes the upper division

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of the carboniferous system. It rests on the easterly slope of the anticlinal axis, and dips toward the south-east. This measure, as regards depth of strata, is on an inclined plane from Lake Erie to the Ohio river, where it is I, 200 feet thick, but crops out at Lake Erie. The structure of the coal basin is by no means of systematic order, nor is the dip uniform —the coal in many instances resting in troughs in a general way parallel with the axis of the main basin, and not unfrequently resting in small basins, as if the coal matter had been deposited in ponds and lakes. This is peculiarly so in Western Pennsylvania and in Eastern Ohio. The irregularity of the coal basin very clearly indicates that it has been disturbed by some internal force before the deposition of the coal matter, if not, in fact, the whole carboniferous series. The disturbance, no doubt, was that which produced the elevation of the Blue Ridge, and when the parallelism of the coal seams was destroyed, and which was, doubtless, before the Alleghenies were elevated, as it is a well known geological fact that the Alleghenies proper were beneath the sea until after the close of the carboniferous age.

The coal strata is but a minor part of the mass of material forming the coal measure, the other elements of the carboniferous system being sandstone, shale, limestone, clay, fire-clay and iron ore.

In geological order, the coal strata overlie the conglomerate and the fire-clay, and almost universally fire-clay is found immediately under the coal ; but in some instances patches of conglomerate have been found above the coal. It is noteworthy, however, that the conglomerate is, to a measurable extent, irregular, and frequently absent, in the coal measure ; but when present its proper location is beneath the coal, and when wanting the coal rests upon the fire-clay and the Waverly formation.

In Ohio there are from six to eight workable seams of coal above the Waverly, interstratified with sandstone, shales, fire-clay and iron ore, forming a mass in vertical thickness of about 400 feet ; the coal seams in the lower coal measure being numbered

110 - HISTORY OF WAYNE COUNTY, OHIO.

from one to seven, commencing with the lowest, and corresponding with the lower coal measure of Pennsylvania.

QUATERNARY SYSTEM.

Crowning the coal measure are the deposits of the drift period, consisting of sand, gravel, clay and bowlders, the productions of the glacial eras, all of which have been transported from their

original localities, and which, as a mass, constitute the surface of the greater portion of the State.