72 - HISTORY OF ERIE COUNTY CHAPTER XI. (RETURN TO THE TITLE PAGE) GEOLOGY OF ERIE COUNTY. THE labors of those who during the last two hundred years have devoted themselves to the study of the structure of the globe, and the claim which this department of human knowledge has to the name of science, depends upon the symmetry which has been found to prevail in the arrangement of the materials composing the crust of the earth. By the slow process of adding fact to fact and by comparing the observations of the devotees of the science in different lands, it has been found that the rocky strata of the earth hold a definite relation to each other in position, and GEOLOGY OF ERIE COUNTY - 73 hence in age ; that many of them are distinguished by constant or general mineral features, and contain characteristic or peculiar remains of plants or animals by which they may be recognized wherever found. It is now well understood, not only that these fossil remains are safe and convenient guides in studying the relations and distribution of the rocks containing them, but that their assistance is indispensable, and that no conclusions can by regarded as accurate and trustworthy unless confirmed by their evidence. The observations of geologists have shown that the materials which compose the earth's crust form three distinct classes of rocks : those that are the direct product of fusion, called igneous; those that have been made up of deposits sits of sediment, called sedimentary; and those that have been changed in their structure and texture, called changed or metamorphic rocks. The igneous rocks are subdivided into two groups, the volcanic and plutonic, of which the first includes lava, pumice, obsidian, etc.; the latter, plutonic, comprises those massive, rocky formations which are without distinct bedding, having apparently been completely fused, and yet were probably never brought to the surface by volcanoes. Having consolidated under great pressure, they are dense and compact in structure, never exhibiting the porous and incoherent condition which is so characteristic of purely volcanic rocks. The plutonic rocks are granite in some of its varieties, syenite, porphyry and part of basalts, diorites and dolerites (greenstones). None of these igneous rocks are found in place in the State of Ohio, though they exist in vast quantities in the western mining districts and on the shores of Lake Superior. It is supposed that these igneous rocks were the first formed and that they constituted the primeval continents. As soon, however, as these rocks were exposed to the action of the elements they began to be worn down and washed away, and the materials derived from them were deposited as sediments in the first existing water basins. That process has been going on through all subsequent ages, so that by far the larger part of the rocks which we now encounter in the study of the earth belongs to the class of sedimentary deposits. These are known to us as sandstone, shale, limestone etc., the consolidation of the comminuted materials having been effected by both chemical and physical agencies. The differences which we discover in these sedimentary rocks are, for the most part, dependent on very simple causes, such as we now see in operation on upon every coast. The showers that fall on land give rise to rivers, and these on their way to the sea excavate the valleys through which they flow, transporting the materials taken into suspension to the point where the motion of their currents is arrested and their power of suspension ceases, in the water basins where they empty. In the gradual arrest of the motion of river currents the coarsest and heaviest materials first sink to the bottom, then in succession the finer and still finer, until all are thrown down. 74 - HISTORY OF ERIE COUNTY. Shore waves are still more potent agents in the distribution of sediments. Whether they break on cliff or beach they are constantly grinding up, and by their undertow carrying away the barriers against which they beat. Nothing can resist their force and ceaseless industry. On every shore where the wash of the land accumulates, we shall find a deposit of gravel and sand which forms the beach, a little off shore a belt of finer sand and clay, while in the depths of the ocean are deposited only organic sediments. When consolidated these materials form rocks with which we are all familiar—the gravel, conglomerate ; the sand, sandstone ; the clay, shale ; the calcareous sediment, limestone. We have also everywhere evidence that what we know as terra firma, is a type of instability ; that all lands are constantly undergoing changes of level, and that over all our continent the sea has rolled, not once, but many times. The grinding effect of shore waves can be witnessed on every coast. In the submergence of a continent, all portions of its surface must in succession come under the influence of this agency. By' its action the solid and superficial materials lying above the sea level, the rocks, sand, gravel, and soil, would be ground up and washed away, the greater part forming mechanical sediments and distributed according to the law of gravitation, the soluble portions taken into solution and carried out to impregnate the ocean waters, and to supply material to the myriads of organisms that have the power to draw from this solution their solid parts. In the advance inland of the shore line, the first deposit from the sea would be what may be termed an unbroken sheet of sea beach, which would cover the rocky substructure of all portions of the continent brought beneath the ocean. Over this coarser material would be deposited a sheet of finer mechanical sediments, principally clay, laid down just in the rear of the advancing beach ; and finally over all, a sheet of greater or lesser thickness of calcareous material, destined to form limestone when consolidated, the legitimate and only deposit made from the waters of the open ocean. Upon the retreat of the sea, the surface of the land would again be covered with vegetation, acted upon by atmospheric erosion, washed into hills and valleys, and locally covered with sand or clay, the products of this local washing. Another invasion of the sea would leave similar records of a similar history, with this difference only, that the tribes of animals and plants inhabiting the land and water would, in the lapse of ages, have experienced marked changes. Perhaps in the interval, the old types of animals and plants would have entirely disappeared and others have succeeded them. So that the new sediments would include only relics of the new races. Such is the order of the events that have given rise to the most of the phenomena of geology, and will serve to explain how it happens that we so frequently find sandstones and conglomerates followed by shales or soft clay GEOLOGY OF ERIE COUNTY - 75 rocks, and these again overlaid by limestones ; and, that in the different strata we have different groups of fossils. In the sandstones and conglomerates which are the direct debris of the land, we naturally find almost nothing but the remains of terrestrial plants. In the limestones we find mainly the remains of marine organisms, corals, shells, crustacea, and fishes. All the rocks of Ohio belong to this class of sedimentary strata, and include abundant examples of each subdivision of the two great groups, the mechanical and organic sediments. To the list of sedimentary rocks belongs another kind of deposits, to wit, e chemicals, and are such as have been plainly precipitated from chemical solution, and include rock salt, gypsum, materials which form mineral veins, and those deposited by mineral springs, beds of ochre, and iron ore. Some of these owe their accumulation to the action of organic matter, but not having distinctly formed any animal or plant tissue they cannot be classed as organic sediments. In all parts of the world rocky masses are met with which would not at first sight be referred to either of the classes above named. These are usually found in sheets of greater or lesser thickness, resting in regular sequence one upon another, as though they had once been sediments, but now upheaved and contorted, sometimes standing nearly vertical, and greatly changed both in their structure and texture. They have been called metamorphic or changed rocks. They compose most mountains and have been hardened and made crystalline by the forces that have acted upon them in their upheaval ; they usually bear evidence of having been highly heated, and in some cases even fused in the process, so that some of them can hardly be distinguished from members of the class of igneous rocks. They form all of the mountain chains of our country, and underlie most of New England and much of Canada. We have no representatives of them in Ohio, except such as have been brought by the Drift agencies. These are the materials with which we have to do in the study of the generalities of geology. The sedimentary rocks underlying the earth's surface form what is known as the geological column, that is, they are arranged in a regular sequence which holds good over all the earth's surface. It is true, however, that in no one place, so far as has been observed, is every member of this series present ; for the reason that while any one formation was accumulating in a sea basin, which occupied only a limited portion of the earth's surface, dry land existed at the same time in great areas, and there no sediments could be deposited. All sedimentary rocks have been formed in oceanic basins. The oldest rocks of which geologists have any knowledge are those composing the Canadian Highlands, and those exposed on the northern shores of Lake Huron. These are metamorphic rocks, and underlie a broad belt in Canada extending from Labrador to the Lake of the Woods, and thence to the 76 - HISTORY OF ERIE COUNTY. Arctic Sea. From the circumstance of this area bordering the St. Lawrence River, the name Laurentian has been given to the first named group. These rocks also form the Adirondacks, a part of the Allegheny belt, the Ozark Mountains, reappear in Texas, the Black Hills of Nebraska, and in some of the mountains of Arizona. Bordering and partially overlaying these rocks, are a series of sandstones, limestones, etc., accumulated in the sea surrounding this ancient Laurentian continent, and made up of materials derived from that continent. These strata form what is called the Silurian system, from their exposure in a part of Great Britain once inhabited by the ancient Silures. The lowest member of this system is the Potsdam sandstone, appearing in a belt around the southern margin of the Laurentian area in Canada, the Adirondacks, and the region about Lake Superior, concealed at the Mississippi and reappearing further west. It has been reached in deep borings at Columbus, 0., at St. Louis, and other places, showing that it underlies in an unbroken sheet the valley of the Mississippi. The fossils of this rock are not numerous, and from the fact that no land plants haVe left their traces here, it is supposed that terrestrial vegetation was then exceedingly scanty if not wholly wanting. Resting on this sandstone, and forming by its outcrop a parallel belt of exposure, is a rock consisting of a mixture of lime and sand called calciferous sandrock, and from evidence underlies the surface of an area nearly equal to the Potsdam. This rock holds the lead of Missouri. The most characteristic fossils are graptolites. On this sandrock are found a series of limestones called Chazy, Birdseye, Black River, and Trenton. They contain the remains of shells, corals, trilobites, and crinoids, and undoubtedly are the result of the accumulation of organic matter at the bottom of the great Silurian Sea, when its waves rolled over the old continent. This group is exposed in New York, Canada, about Lake Superior and on the Upper Mississippi, where one of its members holds the lead of the Galena district. On this limestone are found rocks composed of mixed lime and clayey sediments, containing graptolites as the most characteristic fossils. These are slates, and are called the Hudson group. The outcrop of this group forms a belt parallel with and more southerly than those of the older Silurian rocks. In the Cincinnati rocks are found so large a number of Trenton fossils that, though the rocks there are usually regarded as equivalents of the Hudson, they are considered, in parts at least, the representatives of the Trenton. In the successive strata so far we have an illustration of the sequence of deposits made, in every submergence of the land—first, mechanical (sandstone), then mixed (lime and sand), and then organic sediments (Trenton). The earthy limestones of the Hudson group indicate, a shallowing and retreating GEOLOGY OF ERIE COUNTY - 77 sea, an approach to land conditions, and the completion of one circle of deposition. These strata are called the Lower Silurian series, and of these the two latter are of interest in Ohio, because they are the oldest rocks exposed in the State. They are brought to the surface about Cincinnati by an axis of upheaval reaching from Nashville to Lake Erie, in the region of the islands, parallel to the Alleghenies, but of more ancient date. They contain a large amount of bituminous matter, and are the source of oil and gas. In boring for natural gas at Sandusky the Trenton rock was reached at a depth of 2,315 feet. The rocks next above the Lower Silurian series are called the Upper Silurian series. They have been most carefully studied in New York, where they have received their names. The first is the Oneida conglomerate, a rock composed of coarse materials, conglomerate and sandstone, and marks a period of land subsidence, or water elevation, which apparently involved only a portion of the continent, and during which a long line of shore was thickly overspread with coarse materials torn from the coast by shore waves. On this conglomerate lies the Medina sandstone, composed of sandstone and shales, having a little wedge-shaped brachiopod and a sea-weed as its most characteristic fossils. In New York it is 300 to 400 feet thick. It thins and becomes finer toward the west. Its prevailing color is red. It has been found in Northern Ohio in boring for oil. Next is the Clinton group, consisting of shales and limestones, mixed mechanical and organic sediments and containing a peculiar bed of iron ore called fossil ore, which forms a stratum two to ten feet thick, traceable from Wisconsin to New York, thence southward to Alabama. In Ohio it is represented by a limestone in the region about Cincinnati. Where most calcareous contains many fossils, the most interesting of which are two graptolites, the last of the group found in ascending the geological column. We now come to a rock composed of nearly equal masses of limestone and shale, and forms the ledge over which the Niagara River pours, and is hence called the Niagara group. It is not exposed in this county. In the southwestern part of the State the lowest stratum of the Niagara is known as the Dayton stone, one of the best building stones in the State. It underlies Chicago, and from it is derived " Athens marble." In Northern Ohio the rock overlying the Niagara is that which contains gypsum. It is called the Salina from the fact that it is the source of the salt obtained at Syracuse. The New York geologists call it the Onondaga salt group. It is composed of many alternations of colored marls and shales and some impure limestones containing gypsum. It is not exposed in this county. North of Sandusky Bay, in Ottawa county, a bed of gypsum is worked by Mr. E. H. Marsh, of Sandusky. The gypsum lies covered by a few feet of drift. In boring for gas at Sandusky gypsum was found at a depth of about-three 78 - HISTORY OF ERIE COUNTY. hundred feet. There is gypsum on the lake bottom south of Put-in-Bay Island. Next over the Salina is a group of rocks that form a considerable portion of the Helderberg Mountains in New York, and are called the Helderberg group. It is there made up of several distinct strata, mostly earthy limestones. Its lower subdivision is the water-lime. It may be identified by its ever present and characteristic fossil, leperditia alter. The water-lime is exposed on the peninsula in Ottawa county, and forms Put-in-Bay and other islands in that vicinity. At Castalia a large volume of water flows up from orifices in the limestone rock, called Castalia Springs. It maintains an equable temperature and volume throughout all seasons, except that a protracted drought affects its volume. The water is highly charged with lime, and incrusts any object covered by it, and has deposited a sheet of travertine, over a large area in the vicinity. The subterranean channels of the stream are in the water lime, the uppermost member of the Silurian system. This group forms the summit of the Upper Silurian system and completes a circle of sediments which corresponds with that of the Lower Silurian. The history recorded in each case is the same : a submergence of such portions of the continental surface as now carry the sedimentary strata enumerated ; in the progress of each submergence, the spread of shore materials over all the surface covered by the advance of the sea ; this sheet being followed first by mixed mechanical and organic sediments, then by those almost purely calcareous deposits from the open ocean, and finally earthy limestones, indicating a retreating, shallowing sea, and a return to land conditions, during which no depositions would be made on the surface, but which was the necessary starting point for a new circle of deposits. One difference in the sediments of these Silurian oceans is, that the limestones of the Trenton group are nearly pure carbonate of lime, while those of the Niagara series (the Clinton, Niagara, and water-lime) are highly magnesian. The animal life of the two seas was entirely different, except two or three mollusks ; and this probably is the reason for the distinctive chemical characters exhibited by the organic sediments of these seas. In the Silurian racks we find a great number and variety of the lower order of animals and abundant traces of marine plants, but in America no vertebrates and no land plants have been discovered in them, while in Europe remains of both land plants and fishes occur in the rocks of the Upper Silurian. In this country remains of fishes are first met with in the Devonian system of rocks, which are those next above the Silurian. This system is called the age of fishes, as the Silurian is the age of mollusks. The name Devonian comes from Devonshire, England, where these rocks are prevalent. They form an important part of the geology of our country and of the world, occupying a large area of the surface, include one of our most valuable mineral. GEOLOGY OF ERIE COUNTY - 79 staples (petroleum) as a characteristic ingredient, and contain many strange forms of ancient life. The lowest formation of the Devonian system is the Oriskany sandstone (so named from a New York locality), and is a coarse mechanical sediment. A thin belt of sandstone seen near Castalia and on the peninsula in Ottawa county as the equivalent of the Oriskany. Over the Oriskany is a calcareous sandstone from which the lime is dissolved by exposure, leaving it a rough porous rock resembling the Oriskany, ut containing different fossils. It is called the Schoharie grit. It is not found here. The most interesting member of the Devonian system is the Corniferous limestone—so called from the balls of hornstone contained in it. It is a massive, calcareous rock, containing a very small percentage of earthy matter, and abounding in fossils, especially corals, which in some places may be regarded as ancient coral reefs. In this State it forms two belts of outcrops on opposite sides of the Cincinnati upheaval. It is an open sea deposit, the calcareous center of a group of sediments, the product of a great submergence in the Devonian age ; the counterpart in its general features to those which are found in the parallel deposits of the Upper and Lower Silurian series. The fossils of the Corniferous are very numerous and of unusual interest, the most striking being the remains of huge ganoid fishes, similar in general character to those of the Old Red Sandstone of Scotland. This is the most interting and important rock in this county. It is the rock on which the City of ndusky stands, and that which forms Marblehead and Kelly's Island. At Sandusky the upper layers of the Corniferous formation are composed pf a blue limestone of from twenty to twenty-five feet thick, and is known to the geology of the State as the Sandusky stone. It is largely used for building land flagging. The High School building is of this stone and numerous other buildings and dwellings in the city. It makes an excellent flag-stone but long wear renders it dangerously smooth. The lime industry at Sandusky is large. The lime is made from the lower courses of the Corniferous exposed at Marblehead, and is burned there and at Sandusky. This stone is white and has a ,larger percentage of lime than even the Kelly Island stone, which is the same. The white limestone lies too deep at Sandusky for economical purposes. Overlying the Corniferous is a series of shales and limestones called the Hamilton group. In Ohio is usually a soft blue limestone. In this county it can be seen at Prout's Station on the Baltimore and Ohio Railroad. It underlies a narrow belt of territory extending southwesterly from the lake shore at a point half way between Sandusky and Huron to the Lake Shore Railway, between Monroeville and Bellevue. The Hamilton is overlaid by a great mass of black shales called the Huron shales. It forms the banks of the Huron River at Monroeville and below. It 80 - HISTORY OF ERIE COUNTY. can be seen a few miles east of Sandusky in Huron township, on the Lake Shore Railway at what is called the "Slate Cut." In some places it is interstratified with clayey matter. It is highly bituminous, containing about ten per cent. of combustible matter. From this bitumen, by slow, spontaneous distillation, petroleum is evolved, and flows out in springs at a number of localities. The process of distillation also gives rise to gas springs, which are found over the outcrop of this formation. This shale in some places contains concretions of impure limestone, seen along the Huron River where this shale forms the banks,. being washed out by the action of the water. These concretions are sometimes almost absolutely spherical. Some of them contain the bones or teeth of huge fishes. The Huron shale forms a belt of outcrop running across the State from the lake to the River near Portsmouth. Above the Huron shale lies a series of green and blue shale called the Erie, the lower of which are somewhat interstratified with the upper Huron. The Erie shales form the lake shore from the Pennsylvania line to Erie county. It does not appear further west. We now reach the highest group of rocks found in the State, called the Carboniferous system, because it hold's nearly all the beds of coal that have been worked in this country and in Europe. We have in this county only the ower strata of this system, called the Waverly group, the lowest of which is the Cleveland shale. This can be seen in the banks of the Vermillion River. It is black and bituminous. It is unusually well exposed in the vicinity of Cleveland, whence its name. In its Ethological character it is hardly to be distinguished from the Huron shale. The fossils, however, are bones, scales, and spines of fish of small size, and of Carboniferous types, while the Huron contains the remains of fishes of enormous size, and of most peculiar structure, and such as belong to the forma of the Old Red Sandstone. Next above the Cleveland shale is a bed of shale sometimes blue or banded in color, but more generally red. This is called the Bedford shale, and is conspicuously shown in the valley of the Vermillion River, and is exposed at many places in this section immediately underlying the Berea sandstone. It serves as an important guide to those seeking that stone. The Berea sandstone is, geologically, the highest stone in the county, the outcrop of which enters the county on the east line about half a mile from the lake shore, thence it sweeps round to the south and west, passing through Berlinville and a little east of Norwalk. Within the area lying south and east of this line, the Berea underlies most of the surface, but is very generally covered and concealed by the drift materials, and it is only where its more compact and massive portions have resisted the action of erosive agents, that these have been left in relief— that it projects above the surface. The hills in which the Amherst and Brownhelm quarries are located, and the elevation, Berlin Heights, are all masses of this character. They were once bluffs on the lake shore, and GEOLOGY OF ERIE COUNTY - 81 everywhere show marks of the action of water and ice. This stone is largely quarried in the county, and some grindstones are made. Above the Berea is a limestone, a conglomerate and the coal measures, the Glance of the Carboniferous system, but they nowhere appear in this county —we therefore have no coal in this county. We have no representatives in this State of the age of reptiles, the periods of which are Triassic, Jurassic and Cretaceous. They are found in some parts the continent. Above these are formations and deposits of what is called the age of Mammals, consisting of two periods, the Tertiary and Quaternary. No representatives of the former are found in the State, but of the latter we have abundant. They consist of Glacial Drift, Erie Clay, Forest Bed, Iceberg Drift, Terraces d Beaches. The latter period presents a complete change in the physical condition of our continent, and apparently of the whole northern hemisphere; a change not exceeded by that which takes place upon our surface in the alternation from mid-summer to mid-winter. We have evidence that during what is called the Drift period, the climate had changed from that of an all-pervailing warmth to an arctic cold. While in the Tertiary the climate of the Southern States was carried to Greenland. In the Drift period the present climate of Greenland was bought as far south as the Ohio River. Greenland is now nearly buried under snow and ice, and in a large part of the coast, access to the interior is barred by the great glaciers which flow from the interior to the sea. Precisely such must have been the condition of much of North America during the glacial period, for we find evidence that glaciers covered the greater parr of the surface down to the latitude of about forty degrees. The materials known as the Drift deposits are beds of sand, gravel and boulders, and have received the name of Drift, because they have been transported or drifted from their places of origin. The most important facts which the study of the drift has brought, are that in most localities where the nature of the underlying rocks is such as to retain inscriptions made upon them, the upper surface of these rocks is planed, furrowed or excavated in a peculiar and striking manner, evidently by the action of one great denuding agent. Examples of this planing are abundant about Sandusky and on the islands. A good specimen can be seen at Monk's shipyard, and almost anywhere where the upper surface of the coniferous lime-stone is exposed at Sandusky. Beneath the drift deposits the rock surfaces are in many localities excavated to form a system of basins and channels, often cut several hundred feet below the lakes and rivers that now occupy them. The Vermillion and Huron Rivers exhibit this phenomenon and prove that the surface of the lake was once at least one hundred feet lower than now. 82 - HISTORY OF ERIE COUNTY. Upon the glacial surface are found unconsolidated materials, the lowest of which is blue clays, stratified in thin layers containing no fossils, but coniferous wood and leaves ; after the clay, sand, gravel and boulders in large quantities were transported from the region north of the lakes and spread over a large area south of them ; these were floated to their places by ice bergs. Following the water period ensued an era of continental elevation, which progressed until the present level was reached and the drift deposits raised several hundred feet above the ocean level. This took place slowly and was marked by periods of repose. In these intervals of rest our terraces and lake ridges were formed. These ridges mark old shore lines—such is now being formed at Cedar Point. The "ridge roads" are well known and mark the lines of the principal ridges. No boulders are found on the ridges, so that they are of more recent date than the action that deposited the boulders. In some of the ridges in this county is found a yellow sand, light and loamy, and largely used as a moulding sand. The drift deposits have been removed from a great part of Erie county. In the southern part of the county the boulder 'clay is found covering the rock surface. This is blue, or where exposed and its iron oxidized, reddish yellow unstratified clay, thickly set with angular fragments of shale taken from the lake basin. With these are small boulders usually ground and striated, derived from the old rocks north of the lakes. In this part of the county are also found beds of sand and the lake ridges which rest on the boulder clay. These ridges are the effect of shore waves and are old beaches formed when the lake stood much higher than it does now and in the same manner that Cedar Point sand ridge is now forming, and which will ultimately dike out the lake. The part of the county north of the last lake shore, which is the ridge at Castalia, and thence east imperfectly parallel with the present shore, from which the drift has been removed, is covered by a fine sediment mixed with vegetable remains, making a remarkably rich soil, having the characteristics of the prairie soils of the West. The formation of the lake ridges was the last in the sequence of events which make the history of our surface geology, and brings us down to the present time, which seems a period of rest ;. but every day sees something taken from the barrier of Niagara and at no distant day, geologically speaking, Lake Erie will have shared the fate of all lakes and have been drained to its bottom. The solid earth under our feet has a history as well as the people who have lived on its surface. We learn that once a great part of this country was buried under ice like Greenland. Earlier still it had jungles of palms and other tropical plants ; yet further back it lay beneath a wide ocean ; and beyond that time can be traced many still more remote periods, when it was forest-covered land or wide marshy plains, or again buried under the great AGRICULTURE OF ERIE COUNTY - 83 sea. Step by step we may follow this strange history backwards and with as much certainty we trace the doings of Julius Caesar or William the Conqueror. Every quarry and ravine where the naked rock comes to view offers an attraction if we seek to find there the remains of some of those lost forms of plants which covered the land or of those long extinct tribes of animals which once tenanted the sea. These fossils will become not mere things to wonder at. We learn what they most resemble in the present living world and will not rest content until we have seen all that we can discover of the light which they throw upon the former condition of the district in which we find them. Geology thus becomes not a task to be conned from books, but a delightful companion in every walk and ramble, when we find " Tongues in trees, books in running brooks, Sermons in stones and good in everything."