Historical encyclopedia of Illinois, Volume II, part 1, Part 60

Author: Bateman, Newton, 1822-1897; Selby, Paul, 1825-1913
Publication date: 1912
Publisher: Chicago, Munsell Pub. Co.
Number of Pages: 864


USA > Illinois > Sangamon County > Historical encyclopedia of Illinois, Volume II, part 1 > Part 60


Note: The text from this book was generated using artificial intelligence so there may be some errors. The full pages can be found on Archive.org (link on the Part 1 page).


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Beginning near the source of Sugar Creek in the southern part of the connty and proceeding down stream, a succession of sixty feet of strata may be noticed. They are : first, layers of sandy shale and sandstone twenty feet thick; next, brecciated limestone twelve feet thick; black shale three feet thick; soft clay shale six feet thick ; calcareous sandstone five feet thick; bi- tuminous shale six feet ; and Carlinville lime- stone eight feet thick. Below the Carlinville limestone is a thick bed of sandy shaie, which is underiain by a three-foot bed of claycy lime- stone rich in fossiis ; and a thin bed of bitumin-


ous shale. Immediately under it is a two-foot thick bed of coal called Coal No. 8, which out- crops at Riverton. In early days, before the thick deposits which are now used, were dis- covered, it was dug out along the banks of the river at that place, then called Howletts, and on Spring Creek northwest of Springfield. To-day it is not used.


Below Coal No. 8 is a layer of fine clay (three feet thick) an impure limestone (six feet thick) and forty feet of soft shaly sandstone. Thus a typicai section of the top two hundred or more feet of the rocks of Sangamon County would be as follows :


Strata


Feet


1. Soil


1


2. Loess, often clayey 5 to 15


3. Sand 3


4. Iliinois Tili (clay, "hardpan") ... 11 to 20


5. Yarmonth Zone (Sand, muck). 5


6. Kansan Till 20 to 30


7. Shales and Sandstone. 20


8. Limestone (brecciated)


12


9. Shales, black, slaty.


3


10. Shaies, clayey


11. Sandstone, calcareous and fer-


6


ruginous 5


12. Shalcs, bituminous


6


13. Limestone, "Carlinville"


8


14. Shale, sandy


40


15. Limestone, clayey, rich in fossiis.


3


16. Shale, bituminous


1


17. Coal No. 8


2


18. Clay, fine


3


19. Limestone, impure 6


20. Sandstones, soft, shaly. 40


Layers No. 1 to No. 13, are exposed on Sngar Creek. Nos. 14 and 15, which outcrop in a ravine west of the place where the old Spring- field to Peoria road crosses the Sangamon, are fuli of fossils, more than sixty species having been found and described.


Au excellent idea of six hundred feet of strata underlying Divernon, Sangamon County, can be obtained from drill cores which have recently been received at the State Mnseum. In early times, when miners were desirous of knowing what was beneath the surface, it was neces- sary for them to laboriousiy dig a shaft. Such work required many months of inard labor. To- day, one wishing to have an idea of underlying strata needs but to drili a hole by means of


816


HISTORY OF SANGAMON COUNTY


one of the many excellent drilis which are avaliahle. A diamond drill can rapidly pene- trate to great depth at a cost of but two or three dollars per foot. The drili consists of an iron plpe, in the end of which rough diamonds are fastened both on the outer and inner edge. The plpe is rapidly rotated and the core which comes up on the inside of the pipe can he drawn out and is an excelient record of the strata penetrated. Water is used to keep the hole free from dirt. Naturaliy very soft formations, such as those of a clayey or sandy nature, are washed away and their record is lost. The core of this Divernon coal mine is two inches in diameter. A careful record of the boring was. kept hy Mr. Theodore Wilde. Since much of the material penetrated was soft shale or clay easily solubie, It was washed away and the present core is hut three hundred and seventy feet long. The rocks penetrated are alternating Ilmestone, shale, coal and sandstone. It Is a sur- prising fact that the total amount of limestone was but twenty-two feet of pure limestone and but thirty-six feet more of impure limestone, a total of fifty-eight feet. The total sandstones amounted to one hundred and three feet. The shales make up the mass of the underlying rock, there heing three hundred and seventy-four feet of pure shale, or four hundred ten feet of more or less shaiy material of various kinds -- hiue, hlack, green, mottled; fairly hard or soft; cal- careous, arenaceous, mlcaceous, hituminous. The shales are ali soft in comparison to other rocks and rather easily soluble as they represent the mud of the ocean. When stuck in the mud on one of our country roads, the traveler may sol- ace himself with the thought that there is more potential mud helow him-two-thirds of all the rock for six hundred feet beneath being ready to furnish more mud as required! Our farms need never be exhausted, if we can hut wash off the surface! Twenty-five feet of the six hundred consists of coal, a larger total than that of good limestone! The coal varies from heds two inches in thickness to one seven feet eleven inches in thickness.


GEOLOGICAL FORMATIONS .- All of the strata given In the above typical section are found in the Upper Productive division of the Pennsyl- ranian formation- a formation which closes the period commonly called the Carboniferous period -since at that time ail the great coal deposits were formed. The formation is called Pennsyl-


vanian since it Is so weil developed in Pennsyi- vania. The Lower Productive is the division of the Pennsyivanian most coveted hy mankind because it Is the coal division, par excellence. In Pennsylvania the subdivislons of the Pennsyl- vanian, beginning with the bottom, are as foi- lows ; 1, Pottsville sandstone or Milistone grit ; 2, Alleghany series; 3, Conemaugh ; 4, Mononga- hela. The Carlinville limestone of Illinois, No. 13 In the above section, possibly corresponds with the Conemaugh, being In the Upper Produc- tive. The chief coal heds of Sangamon County, Nos. 5 and 6, occur in strata which inay he cor- related with the Upper Freeport and Kittaning, which are parts of the Alieghany series in the Lower Productive formation. In Sangamon County the Upper Productive attains a thickness of about two hundred feet and the Lower Pro- ductive a thickness of about three hundred feet. Below the latter formation is a one hundred fifty foot thick hed of Mansfield (Pottsville) sandstone, finer grained and lacking the coarse gravel which characterizes this formation in Pennsylvania. It was deposited millions of years ago on the upturned and eroded strata of the rocks which constitute the Mississippian sys- tem, so-called since so well developed along the Mississippi River. It consists in descending order of the foliowing members: The St. Louis (St. Genevieve) limestone, one hundred twenty feet in thickness; the Keokuk (Warsaw) and Burlington Ilmestone, the two together forming the Osage group, three hundred feet thick ; and the Kinderhook shales, limestones and sand- stones, one hundred sixty feet thick.


ProceedIng downward layers of shale and iime- stone, 200 feet thlek, are encountered. Their fossiis and physical character indicate that they are a part of the Devonian system. A diamond driil core sunk to a depth of 1,500 feet at Spring- field, shows, according to Savage1 that the De- vonlan hlack shale begins at a depth of 1339 feet. Below the Devonian the Silurian is rep- resented by possihly one hundred feet of Niagara limestone. Judging from strata in other parts of the State, which dlp under the above enu- merated formations, various divisions of the Ordivician and Cambrian formations would he penetrated in a further descent; and it would be noted that one hundred feet of Cincinnati


1Copy of log discussed by T. E. Savage, now in possession of J. A. Udden, Augustana College, Rock Island, Ill.


817


HISTORY OF SANGAMON COUNTY


sandstone and shale, three hundred feet of Tren- ton Galena dolomite and one hundred feet of St. Peters sandstone, underlle the formations pre- viously encountered in deep drilling. Though positive data are wanting, it is more than likely that the Magncsian limestone is, in this region, underlain by Potsdam sandstone, since borings in the northern part of the State have shown these formations to be 1,000 feet in thickness, and to be sloping under the above enumerated strata.


posited was cold, sometimes salty, other times fresh. Sometimes it flowed in a river of water or of ice. At other times it constituted a jake of an ocean. The kind of rock and the fossii remains contained therein lead to such a con- clusion. Sandstonc. shale and limestone are the only kind of rocks native to the county. The sandstones were formed along shores of great lakes or oceans, as they are being formed to-day when waves aud winds carry away soluble or light material from the debris of the


A generalized geological section of Sangamon County exhibits the following strata :


Systems


Series


Rocks


Thickness


Recent or Human


Surface solis


1 ft.


Loess


8 ft.


Pielstocene or Giaclal


Illinoian till


15 ft.


Kansan tlll 16 ft.


Upper Productive


Shales, Ilmestones 200 ft.


Pennsylvanlan


Lower Productive


Kittaning Coai No. 2 ..


300 ft.


Mansfield (Potsville)


Massive sandstone 150 ft.


Chester


Cypress


Limestone 120 ft.


Salem


Limestone 100 ft.


Keokuk (Warsaw)


Shale 200 ft.


Burilngton


Limestone .100 ft.


Kinderhook


Limestone, shale 160 ft.


Devonlan


Shale & Limestone 200 ft.


Silurian


Niagara


Limestone


100 ft.


Trenton-Galena


Dolomite


Ordovlelan


St. Peter


Sandstone


Lower Magnesian


Limestone


Camhrlan


Potsdam


Sandstone


Older roeks than the Potsdam are not found In the State of Illinols. Noticeable Is the ab- sence of the newer rocks which are found in many parts of the world. After the Pennsyl- vanian perlod long eras passed during which the rocks of succeeding periods were formed. Named In order beginning with the oldest they are: the Permlan, Triassic, Jurassic, Coman- chean, Cretaceous, Eocene, Miocene and Plio- cene. The constructive and destructive agencies which recorded the passing of the mnlllenninnis Involved in those perlods, were as active and extended as the agencles whose work has been recorded iu the rock strata underlying the prai- rics of Sangamon County.


ORIGIN OF THE ROCKS .- None of the rocks In Sangamon County were formed by fire as were many rocks in mountain regions. Elther wind or water were the agents active in thelr con- structlon. The water in which they were de-


coast, leaving the heavier and insoluble sub- stances, usually particles of quartz, sorted ac- cording to slze. Farther from the shore line were formed clay deposits and shales which are composed of finer materiais than Is sandstoue, materials which, because of thelr fine sub- division, would be held longer In suspension and transported farther into the region of deep water. Shales indicate that the shore line was sinking when they were deposited upon sand. Farther stili from the shore, water would be reached which was nearly free from mechani- cally suspended sedlments, but which contalned abundance of dissolved salts, chief of which was calcium carbonate. Myriads of protozoa (rhlzo- pods), coclenterata (sponges, corais), echinoder- mata (crinoids, asteroids, echinoids), mollusca (bryozoans, brachlopods, iamelllbranchs, gastero- pods and cephalopods), and vertebrata. extract- Ing the calcium carbonate and other salts from


-


St. Louis-St. Genevieve (Spergen)


Mississippian


coal, unimportant


-


Freeport Coal No. 7


limestone, shaie, sandstone.


818


HISTORY OF SANGAMON COUNTY


the waters, transformed them into shell snb- stances or bones. Upon the death of the aui- mals these shells and bones feli like gentle rain upon the floor of the ocean, forming extensive deposits of calcareous material, which are the chief constituents of limestone. The floor of the ocean rising again, the order was reversed, shale being deposited, then sandstones and gravel. Finally the ocean receding entirely, all the region projected above the water level. Thus the succession of rocks indicates the ehb and flow of the water, the vicissitudes of the periods during which the various strata were being put down.


SOME CHARACTERISTIC FOSSILS .- In addition to the testimony of the rocks themselves is that of the remains of the anlmals which, at one time, lived in the ocean that covered this region, died, were buried in the mnd, changed to stone and thus contributed to the formation of those rocks. The accompanying photographs show fos- sils now in the State Museum, which were fonnd at Roll's Ford on the Sangamon River, about six miles northwest of Springfield, and others found on Sugar Creek a few miles sonth of the city. More than seventy-five different species of fossils have been found in the conuty, but tlie few illustrations here presented are sufficient to give an idea of the life of those remote periods and to show how events, which occurred millions of years ago, are recorded in the rock pages of geological history, a history which deals with snch unlimited periods of time as to dwarf into insignificance the few years within which man has left his records on the earth.


The picture (Fig. 3) is that of a seven- inch mass of coral (Syringopora multattenuata), a coral which lived in communities. The in- dividuals were cylindrical corallites connected by hollow processes or by horizontal expansions. The walls were thick and wrinkled and the in- ner part of the calcareous tuhe was divided by dellcate ridges formed by faint septa. This coral was most luxuriant in carboniferons times.


Another coral is shown in the left hand row of Fig. 4. These corals were single individuals, cone-shaped and about as long as the joint of the little finger of a man's hand. They sug- gest a "horn of plenty." The skeleton of this corai (Lophophyllum proliferum) is ribbed on the outside so as to show the meeting of the hundred or more partitions or septa whichi pro- ject out into the body cavity. As in the case


of all corals, the calcareous portions were cov -. ered by jelly-like masses. Corals are all ex- clnsively marine and indicate that the water cov- ering the country at that time was a part of the ocean.


Brachiopods thrived lu abundance in those waters. From many species the one shown in columu two of Fig. 4 (Spirifer multigranosa) il- lustrates the shape of the shells. Brachiopods were so named since their arms are used as feet. An interesting part of their anatomy are the spirally coiled ribbons which support fleshy cart- ilaginous arms fringed with movable cirri or tentacles, which set up currents in order to hring tood to the mouth.


The third row of Fig. 4 shows mollusks in the group of Lamellibranchiata, animals with lami- hated gills. The shells of this mollusk (Leda, formerly called Yoldia ) had compact, thin walls closed with teeth in two series meeting below the umbones, and resemble in a marked manner, the modern clam in many respects.


Gastropods, animals which walked on their stomachs just as do suails, are represented in Fig. 5. In the left hand column is Pleurotom- aria sphærulata, a gastropod having a spiral of medium height, conic section and snbspherical ontlinc. Several hundred species of these gas- tropods are knowu. Another genus, Bellerophon perearinatus, is shown in the next column of the same figure. It is an interesting anlmal with its shell bilaterally symmetrical and coiled in one plane. The broad aperture, oval in shape, and with fiaring outer lip, produces a striking shape. It was named Bellerophon after a Greek mythological hero. More than three hundred species have been found in the palæozoic era and the maximum of development was reached in the carboniferous period.


The Pyramidellidæ, another family of gastro- pods, all of which were marine animals, are rep- resented by several representatives of the genus Subnlites (Polyphemopsis). The species pera- euta (so-called because in form they are very sharp) and inornatus (not ornamented) are rep- resented iu the next columns of the figure. They are turreted sbelis with oval aperture and sharp outer lip.


In the State Museum there are more than thirty different species of fossils similar to those shown in these two photographs, and they give clear ideas of the relation of the rocks of Sanga-


Philemon Stort


LIBRARY OF ISE UNIVERSITY OF ILLINOIS


819


HISTORY OF SANGAMON COUNTY


mon County to those of similar age in other parts of the world.


CHAPTER XXX.


.


MINERAL RESOURCES.


BUILDING STONE AND OTHER RESOURCES-SAND AND CLAY-TILE AND BRICK MANUFACTURES-COAL DEPOSITS-SANGAMON THIE SECOND COUNTY IN THE STATE IN COAL PRODUCTION-SOIL VARIE- TIES-WATER RESOURCES-NATURAL STREAMS AND WELLS-SURFACE ELEVATION-HIGHEST AND LOWEST POINTS IN TIIE COUNTY-WEALTH OF COAL AND SOIL PRODUCTS.


(By A. R. Crook, Ph. D., Curator Illinois State Museum of Natural History.)


Sand deposits do not exist in any considerable quantity in Sangamon County. These are found along the Sangamon River, derived chiefly from the materials washed out from between the Kansan and Illinoian till. The best sandstone in the county for building material, No. 20, in the typical section given above, outcrops at Car- penter's Mill, where layers from six inches to two feet in thickness and of fair crushing strength can be obtained. The sandstone used in the construction of St. Paul's Episcopal church in Springfield in 1848, was found at Koke's mill, three miles west of the city. The stone is not very firm and weathers to a brown color hy the oxidation of the Iron which it con- talns.


A better building stone is furnished by lime- stone (Fig. 6), the stone obtained from the ma- jority of the eight quarries indicated on the accompanying map. As will be noted it is ex- posed in various creek beds and is widely spread over the county. This is the material which was employed in the construction of the old State House erected at Springfield between 1837 and 1853, at a cost of $260,000, but whichi is now the county building. The chief quarry for the stone, No. S in tile typical rock section given above, was at Crow's MIII, eight miles south of the public square in Springfield. The


place which, at that time, was a rocky quarry, has been smoothed out by the hand of time, so that now a visitor at that place sees scarcely a trace of the former excavatlons, a green carpet of grass and clover having been spread as a mantie over the old quarry. (Fig. 7.) The present State House is coustructed of Niagara limestoue obtained from the quarries of Joliet and Lemont. Since the Crow's Mill limestone soon turns to an unattractive brown shade, it is not much prized in building. However, it is abuudant enough in quantity to furnish a val- uable stone of medium grade, which cau be used to advantage in the construction of foundations, in bridge building and in the manufacture of quicklime.


CLAY PITS .- Much more valuable as a building material thau the products of any of the quar- ries is the output of the clay pits. In quantity clay is practically unlimited. The manufacture of brick, tile and earthen ware, though in its iu- fancy, yields annually considerable sums. For example, in this county iu 1906, dralu-pipe to the value of $10,194, and hrick to the value of $208,732 were produced. There are thirteen companies engaged in this industry. The ma- terial which they employ is obtained from either the yellow loess-like ciay, six to eight feet In thickness; the weathered clay, six feet thick, underlying; or the blue, compact clay, forty- five feet thick, which Is below that. All of these materials produce brick of average strength and about 2.66 iu specific gravity. A typical analysis of the composition of the clays used in the manufacture of brick at a Spring- field clay pit is as follows :


SiO2 = 60.31 Al2 O3 = 17.74 0 =6.71


Fe2 O2= 5.04 K2 0 = 2.88 MgO = 1.96


FeO = 1.96 Na2 0 = 1.07 TÍO2= . 84


H20 = . 81 CaO = . 41 S = . 14


COAL DEPOSITS .- The clay, sand, limestone and sandstone are far surpassed in value by The coal mined in the county. Forty-one miues, Thirty-seven of them producing, are located on the accompanyIng map. Their output in 1906 gave Sangamon County the leading place as coal producer in the State of Illinois, and since that tinie its premiership has been contested by WIII- iamson County alone. Iu 1908, 6,553 men work- ing in these mines produced about five million tons of coai which cost the consumer some- thing more than teu million dollars. No otiler


820


HISTORY OF SANGAMON COUNTY


single source of wealth has contributed so much to the prosperity of the people in this county. In his work on the geology of the State, in the 'Sixtles, Mr. Worthen1 numhered the different coal heds of the State from 1 to 17, one heing considered the lowest and oldest geologically, and the others supposed to follow in numerical order. The chief heds of the county lie ahout one hundred and sixty feet helow coal No. 8, which, as pointed out in the typical section ahove, is ahout one hundred feet beiow the sur- face deposits; in other words, the chief coal deposits are from two hundred to three hun- dred fifty fcet helow the surface, while south of Sangamon, for example at Mt. Olive, in Ma- conpin County, they are four hundred twenty- five feet, and in the county east (Macon), at Decatur, they are six hundred feet deep, due to the prevailing dip of the strata to the south and east.


The two heds, Nos. 5 and 6, are readily dis- tinguished hy their physical characteristics. No. 5 is known as Horseback coal, hecause of clay fissures or horsehacks due to vertical partings, filled with clay when the fissures are wide or with shaly calcareons deposits when narrow. The hed is six feet thick, has a good roof and furnishes a large output. Bed No. 6 is called Blueband coal, since ahout two feet from the hottom of the hed there Is a horizontal hand of slaty material from one inch to an inch and a half in thickness. The separation in this coal is along horizontal rather than vertical lines. The bed is from six to eight feet thick. Com- position and ash content of Nos. 5 and 6 are quite similar, though No. 6 contains a slightly larger amount of moisture, and it is said that No. 6 affords the largest amount of heat for a given sum of money.


Two higher coals, too thin for use at present, lie fifty and one hundred and sixty feet, respect- ively, ahove No. 5. Several beds have been found below No. 5. At Riverton a dlamond drill showed two seams, each about two and a half feet thick, lying respectively one hundred and twenty-five feet and two hundred and fifty feet helow No. 5, and a four foot hed at three hun- dred twenty feet below No. 5.


In the drill at Divernon the first coal en- countered was a nine inch seam at a depth of one hundred and fifty-one feet helow the sur.


face. This is prohably coal No. 8 willch out- crops at Riverton. At a depth of two hundred sixty-one feet, a two inch seam was met, and at three hundred twenty feet the hest coal bed of the county, No. 6, was discovered. It is seven feet eleven inches in thickness. Not satis- fied with this bonanza the drillers proceeded fartber with the following result: At three hundred sixty-nine feet they found a bed ahont three feet thick; at three hundred eighty feet, one one foot thick ; at four hundred thirty feet, one two feet thick ; at four hundred sixty, one one foot one inch thick; at four hundred ninety feet, one a foot and two Inches thick ; at five hundred fourteen feet, one a foot and eight inches ; at five hundred fifty-nlne feet, one four feet five inches thick. This was the iast hed found and at six hundred and four feet the horing. was discontinued, since a conglomer- ate was reached which was thought to be a part of the Mansfieid formation. Though a line of demarcation between the Upper and the Lower Productive is difficult to locate in this horlng, it may possibly he found at ahout two hundred seventy-five feet below the surface.


Coal is the most valuable product of the county and but few counties in any State in the United States, even in those regions reputed for thelr mineral wealth, derive more valuable or nseful inlneral snhstances than this which is ohtained right here in Sangamon. Without these coal seams in this or other regions, there could be no manufacturing on a large scale, no railroads, no citles.


The following represents a typical analysis1 of Sangamon County coal. Moisture, 10.5% ; Asi, 7.7% ; Volatile material, 38.9% : Fixed carhon, 42.9%. The pure coal amounts to 74.25% and the sulphur 3.5%.


Physically the coal is sometimes shaly, hut usually compact and hreaks with conchoidal fracture; its hardness is 2.5; its specific gravity 1.4. In color it is black. The color of its powder is brown. In luster it is earthy, vitreons. It dissolves in potassium hydrate without coloring the solution hrown, as does iig- nite or other iess completely mineralized hydro- carbon compounds. .When bleached in nitric acid and potasslum chlorate and washed in aico- hol, its vegetahle texture can be plainly seen and this Is one means of knowing that coai has been


1Illinois State Geological Survey, Bul. No. 3, 1906. p. 73.


1Worthen, A. H., Geological Survey of Illinois, chlefly Vol. V, pp. 306-319.


Louisa. PeBrasfield Stout


-


LIBRARY UNIVERSITY OF ILLDS


821


HISTORY OF SANGAMON COUNTY


made from vegetation. Another means of estab- lishing this fact is, that coal can be actually made in the laboratory by heating wood in a test tube. First a white cloud of steam is driven off. Then oxygen and hydrogen are separated leaving lignite. Next, when the tube is closed to keep the oxygen of the alr from unlting with the carbon, carburetted hydrogen is formed after continued heating. This gas explodes the weakest part of the tube and is burnt off. As tbe heating is continued tar is formed, then bituminous coal and finally anthracite. A third reason for the belief is, that coal Is now being slowly formed where wood, buried and pro- tected from oxidation, Is losing its less stable constituents, as, for example, in peat swamps and in abandoned mines. The timbers in an abandoned mine in the Hartz mountains, which had stood under water for five hundred years, upon the draining of the mine recently, were found to have been changed to lignite. Again, In many mines tree stumps are still in position. And finally, more than five hundred species of plants have been found in coal. It is thus evident that the materials which furnish the coal are vegetable, but the manner of their ac- cumulation is not so clear. When exposed to the air wood rapidly oxidizes, but when pro- tected under water, conditions are favorable for gradual loss of volatile material with reten- tion of fixed carhon. Peat swamps furnish favorable surroundings for coal formation. Ma- terials carried to them hy floods are protected from oxidation. Vegetation grows on the bottom, on the top and, throughout the mass of algæ, inosses and other low vegetable forms. The swamp being burled under clay and saud and depressed by change of level of supporting strata, is compressed by the great accumulation of material. Alternate rising and sinking of the land may occasion a repetiton of these processes, until several layers of coaly materlal are formed. Subsequent deep burial, great pres- sure and final elevation produces a coal field with various layers. The cross-sections of the coal fields lu Sangamon County show that such must have been the history of the formation of our coal.




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