of
Muscatine County Iowa
1911
| History of Muscatine County Iowa 1911 | |
Source: History of Muscatine County Iowa, Volume I, 1911, pages 66-73
GEOLOGICAL HISTORY. Little or no disturbance has occurred in this county since the oldest rocks to be seen within its borders were laid down. For this reason the study of the order and history of the successive groups is comparatively simple.
The streams with the exception of the Mississippi, Pine creek, Mad creek, Lowe's run and the Cedar at Moscow, have not cut through the drift which thickly covers almost the entire county. Along the Mississippi east of Pine creek, between high and low water, a rock is exposed, consisting apparently of clay, fine sand and limestone. It is of little or no economic value, somewhat fossiliferous, casts of Spirifer Capax being the chief fossil. This argillaceous limestone, or a little more of the nature of sandstone with few or no fossils, is seen at the mouth of Pine creek, just above high water in the Mississippi. Passing up Pine creek one mile to the mill, a limestone appears in the bank of the creek, containing several species of fossils, among them good specimens of Spirifer Capax not casts, a species of orthoceras, favosites, etc. About one mile still farther up is a bold bluff of sandstone, the base of which must be some thirty feet or more above the highest limestone at the mill. A talus covers everything near the creek, so that the junction between the sandstone above and limestone below, cannot be seen. This bluff rises vertically perhaps seventy-five feet and bears on top a number of fine old pines from which the creek takes its name.
Following the west branch of Pine creek some three or four miles further, it cuts into the limestone twenty-five feet or more and the sandstone is seen as a thin bed on top. Here the corals and brachipods must have had a sort of metropolis. In half a day over twenty-five species of fossils were found in these limestones. *** Near Moscow a fine species of what is probably a Phillipsastrea, a fragment of a fish tooth, and many other fossils were found. The Phillipsastrea grew in a layer hardly two inches thick, spreading over the uneven surface, sometimes a foot or more in extent. It is exceedingly compact, presenting the color and appearance of ivory when polished. There are dark, radiating centers, about one-fourth of an inch in diameter, and from three-fourths of an inch to an inch apart. The spaces between these centers are nearly white and dimly show waving rays joining the rays in the dark centers. No boundary line can be traced between the calicles or corallets. It appears to be a new species. Passing about ten miles northwest to Moscow, or some two miles beyond, where the Chicago, Rock Island & Pacifc Railroad has opened a quarry, many of the same fossils abound. I have taken at this place Acervularia davidsoni, Favosites----named Spirifer pennatus, Platyceras----a fragment of a large tooth of a fish, etc. This fragment is one and three-fourths inches long and seven-eights of an inch in diameter, being nearly cylindrical.
At the mouth of Pine creek, the limestone beneath the sandstone is hardly above high water in the Mississippi. At the mill it is about ten feet above the creek and near Melpine the sandstone has disappeared or nearly so, while at Moscow probably lower beds of the limestone appear. The limestone at Moscow is not less than seventy-five feet higher than at the mouth of Pine creek, making no note of what is very probable, that the upper rocks near Moscow are of a lower horizon than those at the mouth of Pine creek. This is the best, in fact, the only, section of rock exposure across the country, nearly at right angles to the Mississippi. From this it appears that the surface of the limestone on which the sandstone, seen at short intervals along the entire Mississippi bluff in this county, rests, must dip toward the river. The sandstone, therefore, thins out and disappears three or four miles back from the river. The limestone at Moscow and on Pine creek is of the Hamilton group of the Devonian age. At the mouth of Geneva creek, three miles above Muscatine, between high and low water, a limestone is exposed, rich in Stromatopora, and containing Euompholus, Terebratula, Orthoceras expansum (?), Choetites, etc. This rock is an impure limestone, indicating a changeable state of the water--sometimes muddy, when much of the life was destroyed, and then it became clear, when the corals and other forms of marine life flourished. Here the sandstone is seen some eighty rods back in the bluff. It must rest on this impure, argillaceous limestone.
About one mile above Muscatine, in Burdett's slough, and a little above, just above low water, a very sandy rock of the limestone order is exposed. It contains casts of Spirifer Capax and some corals. About two miles from the mouth of Mad creek this rock has been quarried. This is the last seen of limestone in this county. They appear to dip to the southwest a little more rapidly than the river and disappear. The surface of limestone along the river was depressed at Wyoming Hills, as would appear from some bituminous shale nearly at low water, the remainder of the steep bluff rising about two hundred feet in two great steps of sandstone. This shale may be of the same horizon as the coal beds--some three or four miles above the hills and about the same distance below. This sinking must have occurred after the coal and before the sandstone was deposited, since the latter does not appear to have been disturbed.
The coal just below Pine creek and Geneva creek is from twenty-five to thirty feet above high water, but the bituminous shale at Wyoming about midway between these two points is scarcely above low water, and as no indication of coal is seen above the shale at this point, the coal bed here must bend down some twenty-five or thirty feet. Throughout a part at least of the rock exposure along the Mississippi, the limestone is succeeded by a soft, non-fossiliferous, bluish shale, best seen at the foot of the bluff, in East Muscatine. At this place it is ten or more feet in thickness. It is probable the bed of coal just above rests on this shale. The coal which succeeds the shale is of fair quality and some twenty inches to two feet in thickness. This bed is now worked just below the mouth of Pine creek and just below the mouth of Geneva creek. A number of years ago large quantities were mined under the City of Muscatine but these drifts are now abandoned. West and southwest of Muscatine no coal has been found, nor at any point in this county more than a mile or two back from the Mississippi. This leads to the conclusion that the coal of this county is a part of the great coalfields of Illinois and that the bed thins out and disappears a mile or two from the river. It is certain that whatever coal is found in this county must lie above the limestone, of the age of that quarried on Pine creek near Melpine. In the northwestern part of the city of Muscatine, about a mile and a half from the river, near Pappoose creek, perhaps twenty-five feet above its bed and on a gentle hillside, in leveling for a brickyard, a bed of coal was discovered. This bed has for a considerable distance no roofing other than the drift. The floor of the bed is very uneven, rising in different directions quite rapidly. The coal is believed to be of better quality than from the apparently lower beds along the river. Whether this is really a higher bed of coal or whether some disturbance of the nature of a fault has occurred here, is not yet certain. This bed may extend back a mile or more, but from a study of the rocks exposed on Mad creek and Lowe's run, it must be a small field. Over the coal, with the exception of that last named, is some thirty-five to forty feet of sandstone. In some parts this is heavily bedded, nearly pure sand, hardens on exposure and is a good stone above ground. In other parts it is argillaceous, laminated, and contains numerous globular or cylindrical concretions, not generally more than two inches in diameter, or ten inches long, of sulphide of iron. In the city of Muscatine, many years ago, some most remarkable cases of concretions were brought to view. They were spheres from five to six feet in diameter, impregnated with iron sulphide and laminated or stratified the same as the containing rock.
The cylindrical concretions generally commenced around what is thought to be a cone from some cone bearing tree of that age. In this sandstone, which is exposed on Pine creek, about two miles above its mouth, at Wyoming Hills, near the mouth of Geneva creek, in the city of Muscatine, two miles west of the city along the bluff, four miles north of Muscatine, on Mad creek, and three miles west on Lowe's run, are two or three species of Lepidodendrons, at least three species of fossil ferns, two Pecopteris and one Neuropteris, one or two species of Clamites, probably two species of Sigillaria, an Asterophyllites, and several other species of fossil plants. There can be no doubt that the coal and overlying sandstone belong to the coal-measure period but are not connected with the coalfields along the Des Moines west and southwest. No rocks are known to exist in this county above or newer than the sandstone just decribed.
It has already been stated that with little exception the surface of this county is covered with a deposit called drift. This must rest on the sandstone as far as it extends, and then on the limestone next below. It is mainly to this drift that we owe the wealth and continued prosperity of our people. It determines the character of the soil and consequently the kind and quantity of products. Drifts consist of clay, sand, quartz and granitic pebbles and bowlders. We have seen that no rocks in beds are in sight in this county except soft sandstones and but little harder limestones and these are more or less filled with fossils. What then shall we say of those hard rocks, in some cases weighing tons, more or less globular, with no fossils in and on this loose material which make our soil? A very slight inspection leads to the conclusion that they are strangers here, which have strayed from our homes. Many of these bowlders are flattened and have scratches or grooves running across these flattened surfaces. Good specimens of such may be found a mile or two from Muscatine, up either branch of Mad creek. In probably every state in the latitude of Iowa and north where the drift has been moved from a firm stratified rock beneath, scratches and grooves are seen in the rock similar to those on the bowlders. So far as is known, nothing of this kind has been seen in this county but in other parts of Iowa they occur. Our sandstones would not retain such marks. If the drift were removed from the limestones I have no doubt such marks would be found. From the fact that beneath the drift hard rocks in situ are often grooved and bowlders in the drift are likewise grooved, it is plain that the bowlder must have been pushed or dragged, under considerable weight, over the rock below. How far these bowlders have been moved is not always easy to determine, yet we know it must have been from the region where ledges of such rock as that of which the bowlder is composed exist at the surface. No such ledges exist in Iowa; in fact, none nearer than northern Wisconsin and Minnesota. That these bowlders came from the north is certain, from the fact that a degree or two south of us, no bowlders occur, except under special circumstances, but they extend north almost without limit. If we ask how this transportation has taken place, we can find no other agency capable of doing such work except ice. It must have been ice that pushed these bowlders over the country from Lake Superior to Muscatine. The ice must have covered the whole of Iowa and Illinois, Indiana and Ohio as far south as thirty-eight or thirty-nine degrees of north latitude, and at the same time, all the region north. There is reason to believe it was not floating ice but rather of the nature of one great glacier, extending from the arctic regions over the whole of North America to the limit mentioned above. This mass of moving ice, earth and rocks was, most likely, several hundred feet thick. We can easily understand how not only the bowlders and the rocks over which they passed were grooved but all the softer rocks were crushed to sand, clay or fine mud. By this means no doubt many of the upper layers have been entirely ground up and removed. The time in the history of the world when this took place has been called the Glacial epoch. The unconsolidated material of our fertile hills and rolling prairies is the product of the glacier. In many instances, in digging wells in nearly all parts of the county, at from eight to fifty feet below the surface, limbs and even trunks of trees often in a good state of preservation have been found. Two instances in the city of Muscatine, one at Benjamin Hershey's creamery, one near the Summit, one in Wilton, two near Durant and three or four in the vicinity of Sweetland Center, have come to my notice. I have seen a few instances of what appeared to be an old surface, black, rich looking soil, from twenty to thirty feet below the present surface. One or two cases have occurred where the water in wells has been a very disagreeable odor, as if it came from some old swamp or other decaying material in the drift. I have in my possession a limb about an inch in diameter, cut through by a beaver. This limb, with several others, was taken from a well about fifteen feet deep, in the northern part of Sweetland township. It seems most probable that after glaciers had spread over this region and driven away or destroyed all life, a milder climate ensued, during which time forests grew, a rich vegetable mold accumulated and beavers flourished. The trees, so far as I have been able to ascertain, were pines, willow and magnolia. The climate must have been much as it is now. This was followed by a second period of cold quite similar to the first in action and effect, burying the forests, in some instances, fifty feet deep. The deep channels that had been formed through the long ages from the Coal Measure period to the glacial epoch, during which time this region was above the sea, were filled with the crushed rocks along their shores and transported material from the north. When the last glacier began to recede, our present hills were outlined and the courses of our rivers and creeks determined. At the southern end of the glacier great floods of water were seeking the lowest line to the sea. The loose and very soft earth under and in the glacier may have been nearly level but the waters would quickly find the lowest places and thus ravines would begin, down which occasionally great masses of ice would float. In this way the slowly retreating and sometimes advancing glacier aided in forming our main channels. The sculpturing of the landscape into its multitude of hills was left to the rains and snows.
Plant life has already been mentioned but it should be stated that almost nothing has been done toward a full study of this subject. It will require much time and patience to bring the whole into its proper place. If gentlemen who are so fortunate as to bring to light some good specimen or fact, would have the kindness to inform some person interested in such subjects so that it could receive a careful examination and be made a matter of record before it is too late, real service would be rendered to science.
In general, it is said there are no fossils in the drift except such as may have been torn loose from the fossiliferous rocks over which the glaciers moved. This, I think in the main is true, and yet if limbs of trees cut by some species of beaver, perhaps Castoroides ohioensis, are found deep in the drift on what appears to have been a rich, loamy surface, the remains of the animal that did the cutting must be of the same age and in the same formation. I should expect to find in this county the remains of some large rodent, the species perhaps extinct, could the old forest bed to any considerable extent be examined, and this, it seems to me, is in the drift. One mile south of Wilton in the south bank of Mud creek, about eighty rods east of the crossing of the Chicago, Rock Island and Pacific Railroad, a large part of the skeleton of a huge pachyderm was exhumed in the summer of 1874. These remains were about eighteen feet below the surface in a sort of sand and clay, perhaps a modified drift or lacustrine deposit. The country for some miles around is quite level. No teeth were found and consequently the species and perhaps even the genus is not certain, but it is thought to be a Mastodon americanus. Some years ago at the brickyard on Mulberry street in Muscatine, the tusk of an elephant or a mastodon was found. It was so much decayed that it could not be preserved. Later there was found in a ravine in the western part of Muscatine a well preserved tooth of a mastodon. The tooth is now in the possession of P. B. Speer of Muscatine. It is six and three-fourths inches long and three and seven-eighths inches wide. There are five rows of double points on the upper surface, the longest being an inch and a half high. It has two roots. Near Wapello on the Iowa river, about twenty miles southwest of Muscatine, fragments of bones of some large animal were found, also the tooth of an elephant. H. Lofland of Muscatine had the kindness to bring me an impression of the tooth on paper from which I collect the following facts: Length, nine and five-tenths inches; greatest breadth, three and five-tenths inches; fifteen transverse wave like elevations on its grinding surface. It is certain that this county was the home of elephants and mastodons either during the warm period in the Glacial epoch along with the beaver, or immediately at its close. The scarcity of the remains of these animals, it seems, strengthens the view that they became extinct here about the close of the Glacial epoch. The burying of wood and the mastodon at Wilton are likely to have occurred about the same time and from the same cause.
After the hills of drift had become clothed with trees, vines and grasses about the same as now, and innumerable little land mollusks found food, deep shade and hiding places beneath old logs and thick leaves, and the American reindeer, Rangifer caribou, was perhaps monarch of our forests, a formation known in the Mississippi valley as the loess was deposited where Muscatine stands. It hardly covers more than three or four square miles coinciding closely with the limits of the city. I am not aware that it exists anywhere else in the county except on the top of Wyoming Hills. The loess at Muscatine rests on drift, a part of which is somewhat stratified and a part may be a sort of river deposit. Bowlders nearly two feet in diameter, coarse gravel, sand and clay may be seen under the loess. This coarse material rises about sixty feet above high water, where its junction with the loess occurs. The base has been pierced in several places in the city to the depth of forty-five to fifty feet, with little change of material except in two instances to find wood at the bottom. The loess rises nearly to the top of the highest hills. Its greatest thickness must be close to one hundred feet. It resembles ashes in texture and color except a slight shade of yellow. It shows little or no stratification, contains no gravel or bowlders. It stands in vertical, exposed walls almost like good rock. The property is believed to be due to lime and very fine sand which on exposure to the air unite and harden. Scattered through the loess in considerable numbers, apparently without regard to order or arrangement, are stony concretions of very irregular forms, tending strongly, however, to be globular, from a half inch or less in diameter to two or more inches. These concretions, almost without exception, are very much cracked on the inside, the cracks extending from a wide opening near the center to a sharp edge close to the surface. They appear as if when first formed they were solid, then the outer surface hardened and became unyielding, and afterward the mass about the center contracted considerably and became too small to fill the space it formerly occupied. Because of these fractures, rarely visible at the surface, what appears to be as hard and firm as ordinary limestone, is reduced to many fragments by a gentle blow. An ordinary sample of the unconsolidated loess when treated with muriatic acid lost twelve per cent of its weight. The material that would not dissolve appeared, under a lens of a power of over five hundred diameters, to be irregular grains of quartz sand. The concretions treated in the same manner lost sixty per cent in weight and no definite grains could be seen with the same power of lens. There is enough iron in the loess to give to brick made from it a bright red color. Vast numbers of land shells are most perfectly preserved in all parts of the loess unless it be near the bottom. These mollusks must have flourished on the hills adjacent to the Loess lake. ***
Not one of the fifty-four species of mollusks now inhabiting the rivers nor of the twenty-one species in the ponds of this county is found in the loess, and only five of the twenty-six species belonging to the land. Between Iowa avenue and Chestnut, north of Fifth street, in grading lot 2, block 99, a bone was taken from the loess about eighteen inches long, somewhat flattened and about two inches wide, covered from an eighth to a quarter of an inch in thickness with the same material as the concretions. This was near the bottom of the loess. Between Linn and Pine, north of Sixth, on lot 4, block 124, about thirteen feet below the surface, in the loess, nearly the entire skeleton of a ruminant was discovered. It was so completely decayed that little could be preserved except fragments of the jaws with the teeth, the whole covered the same as the bone mentioned above. Dr. Joseph Leidy, of Philadelphia, at first thought this was an undescribed species of extinct deer and proposed to call it Cervus muscatinensis but afterward he concluded that it was the American reindeer, Rangifer caribou.
Since no stratification is observed in the loess, it could not have been disturbed by currents. It therefore must have accumulated in a lake which was subject to little or no change during loess time. The bed of this lake at the close was almost at the top of the highest hills. The top of the bluff along the river was more than one hundred and fifty feet higher along the bluffs than it is now. Supposing the water in the river to have been on a level with the water in the lake, the vast valley between the bluffs, from four to eight miles wide, must have been filled with material similar to that seen along the bluffs under the loess. The loess deposit must have extended some distance into this valley, for it could not have terminated as we see it in the river bluffs. The great river may have been more of a swamp than a river, three or four miles wide. Since the loess was deposited, the river has carried away the material from bluff to bluff, about one hundred and fifty feet deep. The hard Hamilton limestone, the top of which is seen about high water near Pine creek, and low water a mile east of the city, dips below the river to the south and west. The soft blue shale, with its coal and overlying sandstone resting on this, offered but little resistance to the river when it was twenty or thirty feet higher than now, and consequently the bluffs are generally remote from the river, where the latter is now confined by the limestone. The space between the present limit of the river and bluffs of sandstone is nearly level and no doubt underlaid by the limestone over which the river once washed.
Muscatine Island owes its existence to the character of the rock in the Iowa bluff. Whether the basis in which the drift under the loess rests was excavated in the rocks before the Glacial epoch, during that time or since, certain it is, the rocks were removed at least to the limestone which is below low water, the excavation filled fifty to sixty feet deep with loose material, on top of which is the loess, and since then the river has returned from near the tops of the highest hills to its present place. It is doubtful if this could have occurred without a change of level. It seems the land must have subsided till the highest points were but little above the river.
Some stream, probably the Cedar, reaching into northwestern Iowa, carried the same kind of water into this Loess Lake that renders the Missouri and its upper tributaries so famous. Here the mud gradually settled as it does now in the reservoir in St. Louis from the water of the Missouri. Patches of loess are known to exist at Clinton, Iowa City and Des Moines, and from twenty to fifty miles of the western border of Iowa was in the great Loess Lake of Nebraska, Kansas and Missouri.
After the loess was deposited, the final topographical features of the county began to appear. The river valleys and the picturesque bluffs are newer than the loess. At no very distant day, the river, or a large branch of it, followed mainly the line of Muscatine slough. The Sand Mound, the northern part of which is in the southeastern corner of the county, is no doubt a part of the debris of the sandstones crushed by the glaciers, washed away by the river, or both. The loose material in the river bottoms of the county is alluvium. It is constantly being changed along the rivers from side to side. Rivers have sort of pendulum motion and the banks yield where they strike.
The geology of the county may be summarized as follows, in regard to ages and groups:
Devorian Age, Hamilton Group, seen along the Mississippi from the eastern border nearly to the city of Muscatine, on Pine creek one mile above the mouth, and on the west branch of the same creek, about six miles from the mouth, also on Cedar, near Moscow.
Carboniferous Age, Coal Measure Group, seen along the Mississippi from the eastern border to a point about two miles west of the city of Muscatine, on Mad creek about four miles from its mouth, on Pappoose creek about two miles from its mouth, and on Lowe's run, three or four miles west of Muscatine.
Quaternary Age, Drift, covering all the county except the loess, mentioned above, and the alluvium along the river bottoms.
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