Cuyahoga County, Ohio - Chapter 43: Geology., 1870

Chapter 43: Geology.

The Map - The Transition Period - Condition of Eastern Ohio then - The Open Sea - Its Inhabitants - The Erie Shales - Cleveland Shales - Bedford Shales - Berea Grit - Cuyahoga Shales - Carboniferous Conglomerate - Topograpby - Surface Deposits - Oii and Gas Wells - Pre-glacial Scenery. :

A stupy of the map accompanying this sketch, which was prepared by Professor Newberry for the Ohio geological reports, will make it easy to understand the geological structure of the county, which is simple and easily made out from the many continuous exposures of the rock strata in the valleys of the streams. All of the indurated rocks of the county are now regarded as sub-carboniferous, and as deposited in that transition period which preceded the deposition of the coal measure rocks.

Geqglogigal Map

At the commencement of this period, the whole of the eastern half of the State of Ohio constituted a part of the open sea, with the shore line of the land on the west extending from Erie county southward, wong a line passing a little to the east of Columbus, thence into what is now the State of Kentucky, the ocean extending around this headland into the State of Indiana, occupying the greater part of Illinois, and a broad expanse to the west.

This ancient sea was inhabited by a variety of fish, among them the most remarkable ganoids known, some of which are described by Professor Newberry in the geological reports. It supported, also, a mass of fucoids and other sea-weeds, and in it was gradually laid down that great mass of carbonaceous shale, the outcrops of which may be seen along a line running from Erie county southward through the State, via Delaware county, and which, with a thickness of several hundred feet, underlies the exposed rocks of this county. It is regarded as the great source of supply of the oil-wells of Pennsylvania and of the gas-wells of Northern Ohio.

Over this, and in comparatively quiet waters, were deposited the Erie shales, colored green upon the map, being the oldest rocks exposed in their natural bed in the county. They are composed of soft, friable, bluish-green shales, with bands of impure limestone, containing a profusion of fossils. They are in this county about five hundred feet in thickness, diminishing to the west and steadily increasing in thickness to the east, and are regarded as the equivalent of the upper half of the Portage group of the New York geologists. In Pennsylvania they contain bands of coarse sandstone, constituting the lower sand rocks of the oil regions. In this county. fissures in the shale are in places filled with dessicated petroleum, resembling albertite, and having essentially the same chemical composition. Where exposed they disclose no valuable mincrals in sufficient quantity to be of any practical importance.

Cleveland Shale

After the deposition of the Erie shales the conditions became such that a large growth of vegetation was supported in and on the shores of the epen water, by the partial decomposition of which the sediment was filled with carbonaceous matter, which, compressed and consolidated, formed the Cleveland shale. This is a bed of black, highly bituminous shale, containing ten to fifteen per cent. of combustible matter, and is the source of supply of most of the oil wells and springs in northeastern Ohio. The shale is tough, in thin layers, and when exposed to the air becomes red from the slow consumption of the carbonaceous matter and the peroxidization of the iron.

The formation is in this county from twenty to sixty feet thick, the lower half often taking on the characteristics of the Erie shale below, showing that the changed conditions at the time of its deposition has obtained from this shale at Bedford quite a number of fish teeth, consisting of species of Polyrhizodus, Cladodus and Orodus; all carbonaceous sharks.

The surfaces of the shale are also in this locality sometimes covered with little comb-like fossils described by Pander, the Russian paleontologist, under the name of Conodonts and supposed by him to be the teeth of small sharks. These I think will prove to be dermal ossicles of cartilagenous fishes, and to be most nearly allied to the shagreen that covers some portions of the sturgeon. (Prof. N., Vol. I, Ohio Geology.) Other eminent paleontologists regard them as the teeth of Annelids. It has also yielded finely preserved specimens of the palatal teeth of Ctenodus Wagnert (NEwB.), of one specimen of which he has furnished me an excellent cast.

Bedford Shales

After the deposition of the Cleveland shales the conditions were again changed and the sediment contained but little carbonaceous matter, the coloring material of the rocks being the blue carbonate of iron. The material deposited was a mixture of: argillaceous and siliceous mud, forming clay shales where the former predominated and sandstone where the latter predominated. The upper part of this deposit is in places conspicuously red at the outcrops, the result of peroxidization of the iron.

At the Newburg, Kingsbury and East Cleveland quarries the deposit is a fine-grained, blue quarry-rock, a serviceable stone for walls, window sills, etc., and. for sawing into flagging stone, but requires a careful selection to exclude that containing iron sulphide, which by oxydization will color and disintegrate the stone. A single firm at East Cleveland furnishes about fifty thousand square-feet of flagging stone per year from this rock, and that from Newburg is extensively used both in and out of the county. The lower portion carries large numbers of molluscous fossils. In the first volume of the Ohio Reports these quarries were described as on the same horizon as the '' Buena-Vista" stone of the Sciota valley, which has an excellent reputation and is quite similar to this Cuyahoga stone; but Prof. Orton in a recent report in Ohio statistics (1878) locates this ''Buena-Vista" immediately above the Berea. Additional work is needed for positive identification.

Berea Grit

From the sediment deposited immediately above the Bedford shale the argillaceous matter was washed out and carried away by running water or shore waves, leaving a nearly homogeneous mass of water-washed sand, which was subsequently consolidated into rock, and constitutes the famous Berea stone, called sometimes the Amherst stone, the Independence stone, the Ohio stone, etc., of Northern Ohio. It is a building stone of great excellence, the best in the State, and equal to the best obtained anywhere. It is about sixty feet thick, fine grained, compact, strong and durable, generally quite homogeneous, and often in massive layers which split with great facility along the lines of deposition, and can be quarried in large or small blocks as the wants of the consumer require. Generally the upper part is in thinner layers, and suitable for flagging stone. The lower part is ordinarily massive, or in thick layers. It furnishes superior material for grindstones, and is the basis of important industries in the country, the shipments from Berea alone aggregating about ten thousand car-loads a year.

The outcrop of this rock is in places covered by the drift, but ean be traced from Olmstead Falls through Berea in Middleburgh township, Parma, Independence and Brecksville on the west side of the Cuyahoga, through Newburg, East Cleveland and Euclid, thence up the Chagrin river thromgh Mayfield and Orange township to Chagrin Falls, where it forms the bed of the river, and down the river on the opposite side to Gates Mills, where it trends eastwardly into Geauga county. In all of these townships excellent quarries could be opened, and the prospective value of this rock within the limits of the county can hardly be computed. In most of the townships quarries are already opened, and there is no city in the United States which can be supplied with a first-class building stone in much larger quantities and at cheaper rates than Cleveland.

The color of the stone differs at the various openings on account of the difference in the anount of iron contained in it, and of the different modes in which this is distributed. At Berea some of it is white, but the prevailing color is gray; at Independence and Chagrin Falls light buff or drab, and in places it is filled with dark colored spots from the unequal distribution of the coloring matter. This is a very general characteristic in the eastern counties of the State.

Plants similar to those of the coal measures and the remains of fishes are sparingly found in this bed. At Chagrin Falls a number of specimens of a ganoid fish - Palaconiscus Brainerdi - have becn' gathered, also shark's teeth, Lingulae and the Ctenaecanthus.

Cuyahoga Shales

A somewhat sudden transition occurred after the deposition of the materials of the Berea grit, and a finely comminated argillaceons sediment was deposited in quiet waters which swarmed with lingulae, discaenal and other molluscous animals. The lingulae and discaenal are so abundant in the shales immediately resting upon the Berea that they have become a reliable indication of its presence below when completely covered by the overlying shales.

The accumulation of this sediment continued until it attained a thickness of between one hundred and fifty and two hundred feet, much of it argillaceous and resulting in clay shales, some so siliceous as to produce a fine grained sandstone in thin layers, and occasionally containing such an abundance of the remains of molluscous animals as to result in an impure limestone.

It discloses in the county no valuable minerals, but should be thoroughly explored for the outcrops of a mass of evenly bedded, hard graiued sandstone, which splits with difficulty, resists abrasion, and is quarried in Trumbull and Summit counties for a paving stone. For this use it is admirably adapted, and in appearance, and under all tests with the hammer, appears fully equal to the stone brought to Cleveland for this use from the State of New York. ¢ is tobe found in the upper half of the Cuyahoga shales, and quarries in it would prove of great value to the City of Cleveland. The Cuyahoga shale in the neighboring counties contains a great variety of well preserved fossils, most of which may probably be found in it within this county.

These four beds, which have been described in an ascending order, above the Erie shale and below the conglomerate, constitute the Waverly group of the 'first Ohio Geological survey, and are colored yellow upon the map. The subdivisions in it, which are so plainly marked in the valley of the Cuyahoga, can not be traced through the State, but the group, as a whole, is well defined, and the term may well be retained by all writers upon Ohio Geology.

Carboniferous Conglomerate

The material laid down upon the Cuyahoga shales presents very much the appearance of the waterwashed and reassorted residuum of a glacial drift. It is a coarse sandstone, containing many well rounded water-washed quartz pebbles, and some large fragments-of various granitic and metamorphic rocks. Whatever may be the mode by which the material was brought to its present position, it was evidently subjected to the action of shore waves, which carried away all the finer material, and reassorted all the sand and coarse gravel, but was not long enough continued to grind up and destroy all the vegetable remains imbedded in it.

It contains, in places, a profusion of the remains of calamites, the lepidodendron, and other plants of the coal measures, which are so well preserved as to show that they were not carried far from their place of growth. The quartz pebbles and coarse grayel included in the deposit are most abundant near the base, and in places constitute the great mass of the rock. It projects into the country from the highlands of the south, on both sides of the river, being the surface rock in a part of Brecksville, Royalton and Strongsville townships, on the west side; and of Solon, Orange and Warrensyille, on the east. Its surface is from four hundred and fifty to five hundred feet above the lake, and is colored red upon the map. From it could be obtained an unlimited supply of good stone for bridge and foundation uses, but the superior quality and nearer proximity to Cleveland of the Berea, makes the conglomerate of little importance, except for local use.

At the time of the deposit of this, the most recent of the indurated rocks of the county, the continent supported no flowering plants; the vegetation of the land and water was confined to sea-weeds, mosses and ferns; no mammals, birds or reptiles had appeared anywhere, the most highly organized animals being ganoids, mud-fishes and sharks; the North American continent extended from the polar regions into but a small part of what now constitutes the United States; The Alleghanies and the Rocky Mountains were not lifted above the ocean, and during all subsequent geological times until the glacial epoch is approached, the history of Cuyahoga county must remain unwritten except as its condition may be inferred from records outside of the county.

During this long period sedimentary rocks, including all those of the coal measures and the Permian of Palwozoic time as well as all these of those Mesozoic and Cenozoic time, and aggregating in thickness not far from twenty-five thousand feet, were deposited; the most important mountain chains of the continent were lifted from the ocean, and by slow accretions the continent assumed its present form. The fauna and flora also changed with the changed condition of the continent, and evidence is not wanting that Cuyahoga county for a long time enjoyed a tropical or subtropical climate, and that its soil supported a luxuriunt vegetation of tropical plants and trees. Many of these have left no representatives in this latitude, but the gigantic Sequoia of California and our own ::agnificent whitewood or tulip tree, Lierodendron tulipifera, are survivors of genera which, in tertiary times, were represented by very many species. The continent was also inhabited by many strange and formidable animals, wild horses, oxen, huge reptiles, birds with reptile-like teeth, mastodons, elephants, etc., the remains of the two latter showing that they were inhabitants of this county; the presence of the others only to be inferred from the fact that Cuyahoga county remained a part of the elevated land of the continent and open to their occupancy.

Of the closing years of this epoch, before the drift, some records remain inscribed upon the rock strata of the county in the form of deep channels of erosion carried below the present line of drainage, and showing that the land formerly stood at a much higher elevation than now, and which will be hereinafter described.

Topography

Second. The glacial action which scooped out the basin of Lake Erie filled the pre-glacial channels of erosion, removed the upper parts of the exposed strata, and covered the whole surface with drift, the debris of local and northern rocks.

Third. Post-glacial surface erosion, which has established recent channels of drainage, and in places assorted and redeposited the material of the drift.

This former greater elevation is evidenced by the channels of erosion or canyons cut through the rock strata to a depth of some two hundred feet below the present surface of the lake; the Cuyahoga occupying one of these channels, and now flowing some two hundred feet above the bed of theancientriver. That this greater elevation and subsequent depression was as contrasted with that of the southern. The denudation of the shore by ocean wayes spreads out the debris, and gives a substantial level to the floor of the ocean, and the elevations of the adjacent land will leave its perimeter little indented with headlands and bays. Long continued subaerial erosion of elevated lands will cut out deep channels, and a subsequent subsidence will convert these channels into bays, the elevated parts, into headlands and capes, giving such an irregular contour and indented shore line as characterizes all the lands of the northern hemispheres, and is one of the many causes of their more rapid advance in civilization, illustrating the fact that geological changes in the remote past have located our harbors, established modern centres of commerce, and determined the relative civilization of different sections.

As the result of these influences and the action of the shore waves of the lake, which has formerly been at a higher level, the surface of the county presents a series of terraces rising from the lake until the old lake ridges are past, rising thence southward with a gradual slope, except in places where the harder rock strata have produced benches or bluffs to the summit of the subcarboniferous conglomerate.

The surface drainage is all into Lake Erie, and mainly by the Cuyahoga, Rocky and Chagrin rivers and their tributaries, the Cuyahoga within the limits of this county occupying the channel of an ancient pre-glacial canyon while most of its tributaries have excavated their rock channels since the drift period. The Rocky river has mainly a recent channel, but runs near an ancient river bed, the mouth of which may be observed a little west of the mouth of the present stream. The channels of the Chagrin river and its tributaries are mostly post-glacial. These topographical peculiarities are the results of agencies which have been in operation for a period long enough before the glacial epoch for subaerial erosion to excavate channels in the rock strata to the depth of some seven hundred and fifty feet, (or from the summit of the highlands to the bottom of the ancient bed of the Cuyahoga,) and long enough since the close of that epoch for the excavation of the recent channels of the Chagrin and Rocky rivers, and for that of Tinker's creek at Bedford. This is but the brief closing chapter of the geological history of the past.

Surface Deposits

The character of the surface deposits has been determined by part of the same causes which shaped the topography of the county - the advance of the great ice sheet from the north which scooped out the basin of the lake, broke up, crushed and pulverized the surface rocks, mingled with this debris a part of the material scooped out of the lake basin, and that brought from the highlands in Canada, filled up the ancient channels, and covered the rock surface with this mixed material. During some stage of this epoch the finer material which would remain long in suspension in the water eddied backward toward the north either in open or ice covered water, and was deposited in the finely laminated clays which are the base of the surface deposits near the lake, and are found in places along the channels of the rivers sometimes resting on the glaciated rock surface, and sometimes upon the unmodified drift.

In places along the valleys this drift-material has been ground up and washed by the action of water, the finer material carried away, and the residue left in _ the form of stratified sand and gravel, containing occasionally large boulders which have resisted all the pulverizing agencies. Along the former margin of the lake the shore waves have washed out the finer portions of this material, ground up the residue and left it in aseries of ridges marking successive elevations of the waters of the lake. Four of these ridges can be identified at elevations of about one hundred, one hundred and thirty-five, one hundred and seventy-five and two hundred feet respectively above the present surface of the lake, resulting in a band of light sandy soil, eminently fitted for gardening and the raising of peaches and small fruits.

The drift-deposit, where it has not been modified in one of these ways, consists of a bed of clay varying greatly in its thickness, filled with the fragments of the local rocks and of all the rocks outcropping to the north to and including the granitic highlands of Canada. These must have included the corniferous limestone now constituting the surface rock about Sandusky, and asa result this drift clay soil is tempered and ameliorated by an important percentage of lime. The upper part of this drift clay is yellow, but where it is of very great thickness the lower part is blue; the relation of each part being such as to indicate that the color of the upper is the result of the slow peroxidization of the blue oxide of iron in the lower clay. This mingled material of the drift results in a tenacious clay soil admirably adapted for grazing, but capable of producing large crops of all our staple grains where carefully and properly culti vated.

Resting upon this drift are many rounded and angular granitic boulders, some of large size, which are ordinarily referred to the '' Iceberg drift," these being regarded as dropped from floating icebergs after the mass of the drift was deposited. This may be supposed to have occurred through the breaking up of the retreating glaciers when it had become so thin as to float upon the water, and thus have constituted the final chapter in the history of the glacial period, or to have been the result of a subsequent depression of the surface and the floating southward of northern icebergs. It is possible, also, that these surface boulders may be the result of the surface erosion of the original drift uncovering the boulders buried in.it. As tending to the latter conclusion may be noted the abundance of these boulders in many places on the northern side of the lake ridges where the shore waves have removed a large part of the drift deposits.

Oil And Gas Wells

Wells have been sunk in the county for petroleum at Brighton, in the valley of the Cuyahoga and Rocky rivers, and in Mayfield, Warrensville and Euclid. Oil, appearing in the lower layers of the Bedford shales and seeping out near the outcrops of the Cleveland shale, has induced these explorations, and some show of oil has been obtained in most of these wells. Deep borings in"Cleveland, one by the Gas Company and one by the Standard Oil Company ncar the mouth of

Kingsbury run, have afforded some gas, while a copious flow has been obtained from a well bored by Captain Spaulding between Cleveland and Rocky River, and a still more abundant supply from a well in the valley of Rocky river.

It is doubtless true that the Cleveland and the Huron shales are the great sources of the supply of the oil and gas obtained from wells in Pennsylvania and obtained in the Mecca (Ohio) oil regions, which is curved upward and saturates the Berea sandstone which there lies near the surface and in places is thoroughly protected by an impervious bed of drift clay. In Cuyahoga county the ravines cutting through this shale have for ages afforded means of escape for all the gas and oil resulting from the slow decomposition of the carbonaceous matter in the shale, and the indications are not favorable for either gas or oil from this source. If either is obtained in the county, it must be that produced from the Huron shale.

The conditions favorable for copious supplies of gas or oil are a heavy bed of bituminous shale, deeply buried below all lines of drainage, which has been slightly disturbed and broken up so as to afford facilities for the production and the escape of the liberated hydro-carbons, a coarse sandstone above to retain the products, and the whole covered with impervious clay or clay shales preventing their escape. The undisturbed condition of the Huron shales and the want of any important bands of sandstone in the Hrie shale above do not point to this county as a favorable site for explorations for oil, but the abundance of gas springs along the lake shore shows that gas is continually escaping and wells bored down to the Uuron shale demonstrate that in places an abundant and long-continued flow of gas may be obtained. But no surface indications will enable any one to predict the result of experiments made in any locality, and while some gas or oil will probably be liberated by any well amount of either obtained can only be determined by experiment. Wherever machinery is used for other purposes and affords a surplus power for drilling, a well could be sunk down at little expense, with a reasonable prospect of obtaining gas and the chance of obtaining oil in paying quantities.

Post-Glacial History

After the drift period the surface was again gradually clothed with vegetation; new forms of animal and vegetable life appeared; new channels of drainage were established, the larger streams generally following the old pre-glacial channels, as excavations in them were more rapid than on rock surfaces; and man soon appeared as the crowning product of Creative Power. Remains of his works have been found in this country and Europe in the drift, by careful observers, in such positions that they have inferred been taken from the modified river drift, and it is believed there is no well authenticated find of this nature which has been taken from the unmodified glaciadebris, and the records of his histor; must yet be regarded as bearing date subsequent to the glacial epoch. His presence in Cuyahoga county during a long period of pre-historic time is evidenced in many ways; but this part of the history of the county belongs to the archeologist, and not to the geologist.

Pre-Glacial Scenery

Prof. Newberry, in his report upon this county, says: '' These bluffs (of the Berea) unquestionably, were once the shore cliffs of the lake, and anterior to that time the stratum of the Berea grit stretched | across the valley of the Cuyahoga, probably forming a shelf over which the river flowed in a cascade rivaling in hight, if not in volume of water. that of Niagara.

It is not difficult, from a study of the character of the rock strata, to reproduce the scenery which characterized the Cuyahoga valley during the time of the erosion of this ancient canyon. It is only where there is an alternation of hard and soft rocks in beds approaching the horizontal position, that canyonmaking proceeds with any great rapidity, and in such cases the work is carried on by an undermining process which causes the rock beds, too hard to yield to the erosive action of running water, to break by their own weight and fall in successive fragments into the chasms below them. 'To reproduce the pre-glacial scenery of the Cuyahoga valley, we must erase Lake Erie from the map, and near the center, or a little north of the center of its present location, substitute a winding canyon, draining toward the east, and of a depth approaching one thousand feet, with numberless other similar canyons of similar depth emptying their waters into it.

The land of the county, certainly more than seven hundred and fifty feet above the bottoms of these canyons, how much more we cannot tell, extended far to the north and was covered with a network of canyons, two of which were nearly coincident in location with the Cuyahoga and Rocky rivers. At some time during the process of the erosion of these channels the conglomerate of the Cuyahoga valley was not cut by the canyon at the south line of the county. At that point it then formed the bed-rock of a river which may have been many times larger than the present Cuyahoga, and which poured over its margin in a precipitous fall of three hundred feet, or to the surface of the Berea. The intervening Cuyahoga shales are largely argillaceous and easily eroded. In most places they would all be cut out and carried away until the conglomerate was undermined, giving a precipitous fall from the top of the conglomerate to the Berea, with the bottom of the canyon strewn with huge blocks of the conglomerate which had fallen from the bluff, as it was slowly but continuously undermined. In places there are very hard beds in these Cuyahoga shales which would resist erosion, and at times, in place of a precipitous fall, would be formed a steep decline down which the water would rush in any eddying and foaming torrent, in time removing these harder beds, and when the shale became again more argillaceous, restoring the perpendicular falls.

Below this fall and to the north of it, the Berea would resist erosion until after the Bedford shales below were carried away and the Berea undermined, when the stream would pour over it in a fallof one hundred and thirty-five feet to the bed of the tough impervious Cleveland shale. The latter, resisting erosion, would be undermined by the erosion of the soft and friable Erie shale, and a third waterfall would result of a hight of over four hundred feet. At places, the Cleveland shale is thinner and more | easily eroded, and in such places the lowest fall would gradually approach the second one, be ultimately joined with it, and the water would have clear descent of over five hundred and ninety-five feet. This canyon was intersected with other similar canyons, with | similar waterfalls, one of which joined it in the corner of Bedford township, passing through Northfield, Hudson and Stow in Summit county, where its buried channel is washed by a chain of swamps and lakelets. Rivulets of various sizes emptied into it from both sides, the water falls in a precipitous descent, or in a succession of cascades. In places the decomposition of the argillaceous shales would widen out the canyon, undermine the compact, hard strata above, forming a succession of bold bluffs, from which huge masses would occasionally fall into the whirling torrents below, dense forests crowning the bluffs would add to the picturesque beauty of the scenery, the whole forming an interesting illustration of the resulting beauty from the orderly workings of the forces of nature, where no appreciative eye can see it, but which the student of nature, many thousands of years afterwards, can with a good degree of accuracy reproduce.*

*The thickness and the subdivisions of the rock strata as given in this sketch are taken from Prof. Newberry's report for the State survey, to which I am also indebted for many other facts. M. C. R.