tv&oi, <3 
 
 L<J~ 
 
 U-&U 
 
 State of Illinois 
 Department of Registration and Education 
 STATE GEOLOGICAL SURVEY DIVISION 
 John C. Frye, Chief 
 
 EARTH SCIENCE FIELD TRIP 
 
 m 
 
 METRCMDllS AREA 
 
 MASSAC, POPE AND JOHNSON COUNTIES 
 
 PADUCAH, BROWNFIELD, VIENNA AND LA CENTER QUADRANGLES 
 
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 V 
 
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 Leaders 
 George M. Wilson, I. Edgar Odom, Betty Hanagan and Wayne Pryor 
 
 Urbana, Illinois 
 April 11, 1959 
 
 GUIDE LEAFLET 1959A 
 
 HOST: METROPOLIS HITH SCHOOL 
 
METROPOLIS FIELD TRIP ITINERARY 
 
 0.0 0.0 Assemble caravan on Catharine Street in front of Metropolis High School, 
 heading south. 
 
 0.1 0.1 Stop, Catharine and 9th Streets. 
 
 0.3 O.k Stop, Catharine and East 5th Streets (Route 45). 
 
 0.1 0.5 Stop, continue ahead. _,-- 
 
 0.1 0.6 Slow, turn right on East Second Street. o\/PY L18RARX 
 
 0.1 0.7 Slow, turn left at Girard and East Second Streets. 
 
 0.1 0.8 Caution, railroad, turn right immediately "beyond. 
 
 0.1 0.9 STOP 1 - North hank of the Ohio River. 
 
 Recent history tells us of many pirates who preyed upon early 
 settlers moving up and down the Ohio River. Geological history tells us 
 that the Ohio itself has indulged in a little piracy. Near the end of 
 Pliocene time, the interval of geological time that preceded the Pleis- 
 tocene or "Ice Age," the major rivers that now drain southern Illinois 
 and surrounding regions were present, "but along somewhat different 
 courses than they now follow. The Mississippi followed roughly its 
 present course along the western side of southern Illinois to a short 
 distance north of Thebes in Alexander County, where it turned abruptly 
 into Missouri. The Ohio was only a small stream, heading in western 
 Ohio, until it united with the Wabash north of Shawneetown in Gallatin 
 County. From Shawneetown the Ohio followed its present course to Bay 
 City in Pope County, where it swung to the west and followed a course 
 through the lowland area along the southern base of the Shawnee Hills now 
 occupied by Cache River and Bay Creek. At the time the Ohio flowed along 
 the Cache River-Bay Creek lowland, the Cumberland and Tennessee Rivers 
 united in southern Pope County or western Kentucky, and flowed westward 
 along the present valley of the Ohio. The Mississippi and Ohio then 
 united somewhere to the south of their present junction in Missouri or 
 Arkansas. The courses of the Preglacial Ohio, Mississippi, Tennessee 
 and Cumberland Rivers are shown diagrammatically near the back of the 
 itinerary. 
 
 Although none of the four great glaciers which advanced into Illinois 
 during the Pleistocene or "Ice Age" reached the Metropolis area, they 
 were directly responsible for changing the preglacial drainage to its 
 present form. During the early stages of the Pleistocene epoch the 
 Mississippi abandoned its preglacial course through Missouri, and 
 eroded a deep gorge in the bedrock near Thebes. The Ohio, Cumberland 
 and Tennessee, as far as we can tell, maintained their preglacial courses 
 until the Illinoian (Third) glacial stage. During the Illinoian stage, 
 the Ohio cut through the narrow divide which separated the Ohio from the 
 Tennessee-Cumberland and captured the valley which it occupies today. 
 
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 These major drainage changes "Which occurred during the Pleistocene were 
 probably caused by filling and choking of the preglacial valleys with 
 outwash sands, gravels and clays from the melting ice sheets. The 
 present courses followed by these major rivers are also shown near the 
 back of the itinerary. 
 
 Turn right on Metropolis Street. 
 
 Stop, continue ahead. 
 
 Stop, turn right on East 5th Street, Route kj East. 
 
 Slow, caution, railroad crossing. 
 
 Bear left, on Route k5. 
 
 Entrance to Fort Massac State Park on right. 
 
 This is the site of an early French Fort said to have been built 
 near 1759 • According to Bonnel, Smith in his History of Southern 
 Illinois relates the following about Fort Massac. "It seems to have 
 been there or was located there during the French and Indian War, which 
 lasted from 175^ to 1763. One date for the fort's origin is 1759. The 
 French surrendered the Fort to the British in 1763. George Rogers Clark 
 arrived at Fort Massac on his famous trip to Kaskaskia. In l80^, Aaron 
 Burr stopped for four days at the fort visiting General Wilkinson who 
 was there with a party of forty United States troops." 
 
 The spot occupied by the original wood stockade has been excavated 
 by State archeologists. Posts outline the compound and buildings. 
 
 Caution, Railroad Crossing. 
 
 Crossing Massac Creek. 
 
 Slow, turn left on Highway IU5 (north). 
 
 Note the flat floodplain of the streams. The valleys in this region are 
 alluviated, that is, they have been filled by clays and sands deposited 
 in back-water lakes during the Pleistocene. 
 
 Note the flat valley and the brown gravel in the stream. 
 
 Slow, turn right into gravel pit. 
 
 STOP 2 . Gravel Pit in the Lafayette Formation. 
 
 From the Upper Cambrian to near the end of the Mississippian Period , 
 Illinois was submerged beneath great interior seas in which large quan- 
 tities of limestones, sandstones and shales accumulated. Late in Mis- 
 sissippian time the land began to rise and sink intermittently, a condi- 
 tion which lasted until the end of Pennsylvanian time. Great quantities 
 of sand and muds were brought into the Illinois basin during this time, 
 often turning the region into great swampy flat coastal plain. It was 
 
Digitized by the Internet Archive 
 
 in 2012 with funding from 
 
 University of Illinois Urbana-Champaign 
 
 http://archive.org/details/earthsciencefiel1959illi 
 
-3- 
 
 under these conditions, which frequently existed during the Pennsyl- 
 vanian period, that our great coal deposits were formed, even though 
 much of the Pennsylvanian se. iments were deposited under marine 
 conditions . 
 
 In Illinois we have no rocks of Permian, Triassic, or Jurassic age, 
 and we have no information to even relate to us the geologic events that 
 transpired during this long geologic interval. 
 
 The rock or red sand at the base of this gravel pit is thought to be 
 of Cretaceous age and the overlying brown iron stained, cross bedded, 
 rounded chert gravel has been correlated with the Pliocene system of 
 rocks. There may be question as to the age of this gravel, for it has 
 not been actually correlated with true Lafayette material, so we will 
 call the gravel in this pit "Lafayette type" and tentatively call it 
 Pliocene . 
 
 You will find chertified Mississippian fossils in this gravel, which 
 gives an indication of the source of some of the gravel. The pebbles are 
 highly polished and are coated with a thin veneer of limonite. This 
 gravel is found in valley deposits and also on the tops of hills as we 
 find it here, indicating that there must have been a great quantity of 
 this material. The distribution of Cretaceous and Tertiary sediments 
 in the middle Mississippi valley is shown near the back of the itinerary. 
 
 The pit is blanketed with loess of Pleistocene age which was picked 
 up from the present Ohio and the ancestral Ohio in the Cache River 
 valley. One has only to be present on a windy day in early spring to 
 visualize just how this loess was deposited, for dust storms are not 
 uncommon here even now. 
 
 Beneath this "Lafayette type" gravel we find the loose red sand 
 which has been called Cretaceous. Geologically we are at the north end 
 of the Mississippi Embayment, which reached Illinois during Cretaceous 
 times. The north end of the Gulf of Mexico reached as far north as this 
 region . 
 
 With the coming of Pleistocene and the advances of the glaciers 
 water in unbelievable quantities followed the preglacial valleys and 
 greatly changed the areas adjacent to the streams. It removed great 
 quantities of the "Lafayette type" gravel, and the underlying Cretaceous 
 sediments so that to the north only hill top deposits and remnants are to 
 be found. New valleys were cut, old ones abandoned, valleys filled with 
 later glacial sediments, and of course the loess which is a fine dust, 
 blanketed the surface of all the sediments to a depth of several feet. 
 
 Just when in the Pleistocene all this activity took place, we are 
 unable to say. Perhaps the beginning of the Pleistocene was one million 
 years ago, but according to Carbon 1*+ dating, the last glacier left the 
 United States in the Great Lakes Basin about 10,000 years ago. 
 
 The section here is as follows : 
 
 ft. in. 
 
 Loess 8-10 
 
 Gravel, rounded chert pebble to 2" in diameter, 
 with much limonitic clay, cemented in part by 
 limonite. This gravel is grossly cross bedded 20 
 
 Chert conglomerate heavily cemented with 
 limonite 6 
 
 Cretaceous, red sand 3 
 
J*. 
 
 Return to cars and return to the highway. 
 
 Stop. Caution on entering the highway, turn right. 
 
 0.8 13.3 Note the Paleozoic rocks far ahead on the north side of the Cache 
 Valley. 
 
 0.7 lU.O Outcrop of Chester (Hardinsburg) sandstone dipping 10 degrees to the 
 north. A fault of minor magnitude crosses the road at this spot. 
 For the next 8 miles we will cross several faults or "breaks in the bed- 
 rock. 
 
 0.2 1^.2 Outcrop of Chester sandstone (Tar Springs) dipping 20 degrees north- 
 west. 
 
 Q.k lh,6 Entering a tributary to the Cache Valley - note the flat alluviated 
 valley floor. 
 
 1.5 16.1 Erosional remnant in Cache Valley - east side of the road. An east-west 
 fault crosses the road here as well as facing on the south side of this 
 low hill. 
 
 0.8 I6.9 Bay Creek Ditch. 
 
 0.3 17.2 Small terrace that has developed since Cache Valley was abandoned by the 
 Ohio River. 
 
 1.0 18.2 STOP 3 . Discussion of the Cache Valley. 
 
 The Cache Valley is one of the most impressive physiographic 
 features in the State. The origin of this broad valley was discussed 
 at Stop 1. At this point the valley is about 3 miles wide. The north 
 valley walls are eroded in Paleozoic rocks and are much steeper than 
 these on the south which are cut in weaker unconsolidated Cretaceous 
 beds. 
 
 The valley is entrenched some 250 to 1+00 feet below the uplands 
 underlain by Paleozoic rocks. The eastern part is now occupied by 
 Bay Creek, and the western part by the Cache River. Both streams are 
 misfit, that is, they seem to be too small to have eroded the wide 
 valley in which they flow. You will note that the north valley wall 
 is very irregular, and that in many places steep cliffs border it, such 
 as the one we can see from this point to the northwest. Some of the 
 cliffs are clearly the result of down-cutting and lateral erosion by the 
 ancient Ohio, but others, the cliff seen to the northwest, are controlled 
 by faulting. A fault passes along the front of the linear cliff seen 
 to the northwest. 
 
 The deposits filling the Cache Valley have a maximum thickness of 
 about 180 feet, and are composed of glacial sands, clays and gravels. 
 Much of this fill is believed to be of Wisconsin age (fourth and last 
 glacial stage), but certainly older deposits are also present. Since 
 good shallow water wells are easily obtained in the valley, few deep 
 wells have been drilled, thus few opportunities for us to study these 
 deposits. 
 
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 0.3 l8.5 Bay Creek. You have noted several depressions in this valley surface, 
 resembling old stream courses. Your observation is correct. 
 
 Railroad crossing. Danger. 
 
 Climbing the Paleozoic escarpment. A fault is at the base of the hill 
 and the rocks encountered here are of lower Pennsylvanian (Caseyville 
 group) c sandstones with disseminated quartz pebbles. 
 
 Slow. Note the strongly dipping beds on the right. Dipping from 10-25 
 degrees northwest. You are crossing a fault zone here. 
 
 Turn right. Note the steep dipping sandstone and shales - 15-25 degrees 
 to the northwest. 
 
 Slow - turn right, entering Route lk6. 
 
 Slow. Note the disturbed, folded and faulted sandstone in the cut on 
 Route 1U6. 
 
 0.1 21.0 Turn right, entering Dixon Springs. 
 
 0.3 21.3 Turn left, note the strongly jointed rocks in the stream. 
 
 0.2 21.5 STOP k . Lunch stop. Dixon Springs State Park. 
 
 After lunch we will take a leisurely stroll south down the stream 
 to see a characteristic feature of the lower Pennsylvanian sandstones, 
 and to take in a little more of the scenic beauty of the park. 
 
 The rocks seen on this walking journey are of lower Pennsylvanian 
 age and are referred to as Caseyville. Specifically they are called the 
 Caseyville conglomerates. The rocks consist of coarse cross-bedded 
 quartzose sand in which there are plant fossil impressions and many peb- 
 bles of white quartz. This sandstone is resistant to erosion and thereby 
 makes the beautiful cliffs that are found in the park. The park is 
 actually located in a down-faulted block bounded on both sides by faults, 
 and also cross-cut by faults. The faults bounding the west side of the 
 block are only a few hundred feet west of the stream. The down-faulted 
 block is called a graben by geologists. 
 
 The nature of the Caseyville sandstones and conglomerates and the 
 undercutting action of the small stream has produced many large boulders. 
 As we walk down the stream note that the number of white quartz pebbles 
 in the sandstone increases rapidly. Lower beds of the Caseyville are 
 characteristically very conglomeratic but the quartz pebbles slowly de- 
 crease upward until in the eund stones of the next youngest Tradewater Group 
 they are non-existent. 
 
 0-2 21.7 Turn around and turn right. 
 
 0.3 22.0 Stop. Caution in entering Route 1^6. 
 
 0.1 22.1 Slow - turn hard right. 
 
 0.1 22.2 STOP 5 - Discussion of the Dixon Springs Fault problem. 
 
-6- 
 
 The rock of southern Illinois has undergone folding, faulting, both 
 tensional and compressive, igneous intrusion by dike forming materials 
 and by penetration breccias, and later mineralization, sometime after 
 the end of the Pennsylvanian and before the advent of the Cenozoic. 
 There have been several times of faulting as has been found in the spar 
 mines. Movement along these fault zones has not really stopped. In 
 l8ll the great earthquake of New Madrid, Missouri, resulted in the form- 
 ation of Reels Foot Lake, Tennessee. This quake was felt in an area of 
 more than one million square miles. Only last fall the Geological 
 Society of America meetings in St. Louis were properly accented by an 
 earthquake in the area while the association president addressed the 
 group on a subject entitled "The Stable Earth." 
 
 The Dixon Springs State Park is situated in a graben in the Penn- 
 sylvanian rocks. (See illustration of types of faults and structures 
 produced by faulting near the back of the itinerary. This graben is 
 about 3 miles wide and nearly 20 miles long. A faulted block which has 
 risen in relief is called a horst. 
 
 Lying to the north for nearly one mile there is a complex of faults 
 of various displacements, ranging from a few feet to several hundred. 
 The Dixon Springs fault has more than 1200 feet of displacement. 
 
 The folding and faulting that has taken place in this area is but a 
 part of a larger folded and faulted region, which includes the Rough 
 Creek-Shawneetown zone; the Kentucky River Fault zcne; the fault zone of 
 southeastern Missouri; the Ste. Genevieve Fault zone, and with the fault- 
 ing of the northern end of the Mississippi Embayment connects vith the 
 faulting of northeastern Arkansas, and possibly connecting with the 
 faulted and folded region of the Ouachita Mountains and the Arkansas 
 Basin. 
 
 We have already indicated that with the folding and faulting that 
 in some areas igneous or molten rock in the form of mica-peridotite rocks 
 came to the surface. In some instances the igneous intrusions came as 
 diatremes or penetration breccia. 
 
 It is thought that the mineralization of southeastern Illinois 
 accompanied this time of igneous intrusion and that mineral charged 
 waters deposited the fluorspar, lead and zinc. Occasionally we find 
 joints filled with some of this suite of minerals even in this area. Of 
 course we find such mineralization in southeastern Missouri and north- 
 eastern Arkansas. 
 
 0.6 22.8 Stop, turn left, note strong dip of sandstone in the ditch on the left. 
 A fault zone is located in the valley on the right. 
 
 0.3 23.1 Note the strong compressional jointing in the sandstone on the left. 
 
 0.3 23.*+ Note the sandstone on the left dipping rather steeply to the northwest. 
 
 0.2 23.6 Slow, turn left. 
 
 0.2 23.8 Stop, turn left on Highway 1^6 (west). 
 
 0.3 2^.1 Slow. Note the dip of the rocks to the southeast in the road cut on 
 
 the right and left. There are several interesting structures here. Two 
 
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 faults, a high angle and a low areile, a small anticline, one limb of 
 which is faulted off, and several other features caused by shattering, 
 squeezing, and folding are present. 
 
 Bridge over Illinois Central Railroad. Note the northward dipping 
 Chester sandstone on the northwest side of the cut. (Tar Springs) 
 
 Note the outcrops of the Tar Springs sandstone in road cut on right and 
 left. 
 
 Note the swelling at the base of the trees in the swampy area on the 
 right and left. There are a number of Cypress trees in this low bottom. 
 
 Slow, entering Grantsburg. 
 
 Crossing Bay Creek. 
 
 Note the Tar Springs sandstone in road cut on right and left. 
 
 Slow. Turn left on Ganntown road. The road is surfaced with Lafayette 
 type gravel which probably came from the pit at Stop 2. 
 
 Note the outcrop of the Waltersburg sandstone on the left. 
 
 Climbing a long gentle slope. The slope roughly corresponds to the dip 
 of the Tar Springs sandstone which can be seen exposed intermittently 
 in the ditch along the road. 
 
 Bear right. Entering Ganntown. 
 
 Note the outcrop of the Hardinsburg sandstone on the left. 
 
 Slow. Turn right on limestone surfaced road. 
 
 The high hill on the far right is capped by the Hardinsburg sandstone. 
 The steep face of this hill is called an escarpment. 
 
 Slow. Turn right (north). 
 
 Crossing Clifty Creek. 
 
 Note the sandstone on the right. 
 
 Climbing the escarpment of the Hardinsburg sandstone. 
 
 Slow. Turn right. 
 
 Slow. Turn left. 
 
 Slow. Turn righto 
 
 Turn left and descend hill. 
 
-8- 
 
 0.1 ^0.2 STOP 6 . Outcrop of Hardinsburg Sandstone along Cave Creek. 
 
 From Stop 5 to this point we have been traveling across rough 
 dissected topography underlain by sandstones, limestones and shales 
 which belong to the Chester Series of upper Mississippian age. Here 
 we see one of the sandstones of this series, namely the Hardinsburg, 
 dipping northward at an angle slightly greater than the stream gradient. 
 The sandstone is thin and evenly bedded. It might be used as flag- 
 stone for making side walks, flooring patios, and even in building 
 houses . 
 
 This outcrop well illustrates the horizontal bedding of water de- 
 posited rock strata. Although it is presently tilted to the north, 
 this sandstone was originally laid down in a horizontal position. 
 Movements in the earth's crust, probably sometime after the Pennsylvan- 
 ian Period and before Upper Cretaceous time, uplifted the whole of 
 southern Illinois tilting the rock strata to the north. As we con- 
 tinue the trip you will note that all the strata dip northward except 
 locally where altered by faulting. 
 
 You will also note that in this region there are a great series 
 of steep sided or asymmetrical hills. These hills are inevitably capped 
 by sandstone. The north slopes of these hills are gentle, conforming 
 closely to the inclination of the bedrock; but the south slopes are steep. 
 This is because here erosion has broken through the resistant sandstone 
 caprock and cut down rapidly through the weaker limestones and shales 
 below. Such ridges are called cuestas, and their steep sides are called 
 escarpments. The map provided shows several of these cuestas trending 
 in a northwest-southeast direction. The most significant cuesta is, 
 however, the one that runs along the northern edge of the Vienna quad- 
 rangle, and is formed by the thick sandstones (Caseyville) that lie at 
 the base of the Pennsylvanian . Cuestas and escarpments are character- 
 istic of regions underlain by weak and hard strata that have been 
 slightly tilted. 
 
 Cave Creek at this point is flowing to the northwest. A short 
 distance downstream it suddenly turns and flows off in a southwest 
 direction. The sudden turn can be attributed to faulting. The stream 
 flows northwest down the back slope of the Hardinsburg cuesta to the 
 fault zone which trends in a northerly direction. Streams often follow 
 fault zones in this region because these zones offer less resistance 
 to their down cutting action. We will see if the fault zone can be seen 
 in the stream where it makes the abrupt turn to the southwest. 
 
 0.2 ^OA Bridge over Cave Creek. 
 
 Q.k hO.Q Note deeply weathered limestone on the right (Golconda formation). 
 
 1.1 Ul.9 Note outcrop of Tar Springs sandstone on the right. 
 
 0.5 k2.k Slow. Turn right. 
 
 1.0 k3.k Stop. Turn left on Highway IkG (west). 
 
 0.6 kk.O Caution, railroad crossing. Entering Vienna. 
 
 Q.k hk.k Stop. Intersection of Highways k^ and 1^6. Turn left (south). 
 
-9- 
 0.7 ^5«1 Climbing dip slope of Tar Springs formation, 
 
 0.8 J+5-9 Abandoned quarry in the Glen Dean limestone on the right. The limestone 
 is overlain by the Tar Springs sandstone and shale. A textbook example 
 of lateral gradation from shale to sandstone is shown in the Tar Springs 
 in this quarry. 
 
 0.8 kS.'J Crossing Dutchman Creek. 
 
 0.9 ^-7.6 Crossing Dutchman Creek again. Note how the stream meanders in its 
 vally. A fault zone parallels Dutchman Creek Valley. 
 
 0.6 U8.2 Note outcrop of Golconda limestone on the left. The Hardinsburg sand- 
 stone which overlies it can be seen on top of the hill. 
 
 0.9 1+9.1 Note outcrop of Cypress sandstone on the left. Note that as we traveled 
 south from Vienna the outcropping strata are older and older. 
 
 0.8 ^9.9 Note the beautiful view of the Cache Valley. Here the valley is about 
 three and one half miles wide. 
 
 0.6 U9.5 Note the bluff of the ancient Ohio River on the right. 
 
 l.k 50.9 Note the low ridges in the flat valley. 
 
 1.7 52.6 Observe the tall Cypress trees in the swampy area on the far left. 
 
 0.1 52.7 Junction of Highway k 1 ? and the Karnak road. 
 
 O.k 53*1 Slow. Turn right into the Mermet Quarry of the Columbia Quarry Company. 
 Park cars in area near the office. 
 
 STOP 7. Mermet Quarry. PLEASE DO NOT GO NEAR THE PIT PILLED WITH 
 WATER. STAY ON THE EAST SIDE. WE CAN SEE THE ENTIRE QUARRY AND THE 
 FOSSILS ARE MOST ABUNDANT THERE. 
 
 The limestone being quarried here is of Mississippian Age and 
 is referred to as the Ste. Genevieve formation. The quarry is now taking 
 approximately 50 feet of rock. The upper surface of the stone is quite 
 irregular and shows the effects of prolonged weathering. Large cavi- 
 ties have developed in the upper surface and are now filled with the 
 red and yellow Cretaceous clays which have overlapped southern Illinois. 
 
 As you see, the upper surface of the limestone here varies as much 
 as ^0 feet. It appears that the first material which accumulated on 
 this surface was the dark red to black iron bearing formation which 
 has been called the Little Bear soil, this is in turn overlain by a 
 reddish yellow clay, then by a reddish sand, then by a brown chert peb- 
 ble formation, then by an angular chert pebble zone, then this is 
 mantled by some 6 to 10 feet of loess. 
 
 The upper surface of the limestone may have as much as 5-6 feet of 
 residual chert between the limestone and the Cretaceous formations. 
 This chert is laminated and appears to be a result of solution of the 
 limestone and leaving the chert and clay residue. 
 
-10- 
 
 The entire sequence though considerably reduced in thickness 
 bears certain similarities with the excellent sequence which is to be 
 seen on the road west of Joppa in the Post Creek Cutoff. The consoli- 
 dated bedrock here is in the Ste. Genevieve while the bedrock in the 
 cutoff is St. Louis. 
 
 The upper surface of the limestone offers you an excellent 
 opportunity to collect silicified fossils. 
 
 The section here is as follows : 
 
 ft. in. 
 
 Loess 6-10 
 
 Chert pebble zone, angular fragments in a silty 
 
 clay matrix k 
 
 Chert pebble zone - rounded brown iron stained 2 
 Sand - reddish and clayey 6 
 
 Clay - mottled red and yellow J+-10 
 
 Earthy iron residual zone. This zone nay correlate 3-8 
 
 with a similar zone in the Post Creek Cutoff. 
 Chert, residual, probably the product of solution on 
 
 the upper portion of the Ste. Genevieve formation h-6 
 Ste. Genevieve Formation - limestone, fine grained 
 
 in part, deeply weathered in upper portion, with 
 
 siliceous fossils standing in relief 2-6 
 
 Limestone, fine grained in part, other parts endo- 
 
 thyrid and oolitic, thin and thick bedded 75 at least 
 
 Thank you for coming. See you at Hardin, May 2, 
 
GEOLOGIC COLUMN - METROPOLIS AREA 
 Prepared "by the Illinois State Geological Survey, Urbana 
 
 t " "7 
 
 Cenozoic ' M 
 
 10 
 
 H 
 
 2 
 
 <+H 
 
 o 
 
 CD 
 < 
 
 PERIODS 
 Quaternary 
 
 EPOCHS 
 Pleistocene 
 
 REMARKS 
 
 Recent post-glacial stage""' 
 Wisconsin loess 
 Illinoian loess 
 Slackvrater lake deposits, 
 
 loess, and slope wash. 
 
 (Stops 1,2, h) 
 
 Tertiary 
 
 Pliocene 
 
 Gravels (Lafayette type) 
 
 Miocene 
 Oligocene 
 Eocene 
 Paleocene 
 
 Clay and sand 
 
 o 
 
 •H 
 
 o 
 
 to 
 o 
 
 CQ 
 1 
 
 CQ 
 <fH CU 
 
 O H 
 
 t: 
 cu -p 
 to ft 
 
 « 
 
 Cretaceous 
 
 
 Sand, clay and gravel 
 
 Jurassic 
 
 
 Not present in Illinois. 
 
 Triassic 
 
 
 Not present in Illinois 
 
 o 
 
 •H 
 
 o 
 
 CO 
 
 O 
 
 cu 
 H 
 ct3 
 P* 
 
 Age of Amphibians 
 and Early Plants 
 
 Permian 
 
 
 Not present in Illinois 
 
 Pennsyl- 
 vanian 
 
 McLeansboro 
 Carbondale 
 
 Shale, coal, under clay, 
 sandstone, limestone 
 
 Tradewater 
 Caseyville 
 
 Sandstone, shale and 
 limestone 
 
 Sandstone, shale and 
 limestone 
 
 Missis- 
 sippian 
 
 Chester 
 (Upper Mis- 
 sissippian) 
 
 Alternating sandstone, 
 limestone, and shale 
 formations 
 
 Meramec 
 Osage 
 
 Limestone 
 Limestone and shale 
 
 «H CQ 
 
 o CU 
 
 .£ 
 
 CU CQ 
 
 <; c* 
 
 CQ 
 CU 
 •P 
 
 «M 03 
 
 O fH 
 
 CU CU 
 bO-P 
 < ^ 
 
 CU 
 
 1 
 
 H 
 
 Devonian 
 
 
 Not exposed in field 
 trip area 
 
 Silurian 
 
 
 Not exposed in field 
 trip area 
 
 Ordovician 
 
 
 Not exposed in field 
 trip area 
 
 Cambrian 
 
 
 Not exposed in field 
 trip area 
 
 Proterozoic 
 
 Archeozoic 
 
 Referred to as "Pre 
 Cambrian 
 
 No data available 
 
/ 
 
 
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 V- 
 
 \\ l£ 
 
 .O-n 
 
 -~ ^v \ 
 
Ill f,\7pip 
 
 1 i 1 X Hanging 
 
 1 f ootwall | ' |V 
 
 1 i 1 ! | | r ■ 
 
 h It i i t ' ' 
 
 1 ' V? 
 
 1 ' ^\ 
 
 1 ' i ' t ' iX 
 
 1 1 1 1 
 
 Q Cj O O O O 
 
 o o ° o O o o 
 £> o o o o o o 
 
 1 1 
 
 
 ^r — — — "~ 
 
 ^"T^T — T~ — 1~"~ 
 
 
 YiYi 
 
 1 1 1 I 1 1 
 
 1 
 
 Hi fl 
 
 — - 
 
 ki i 
 
 -X 
 
 
 r i i 
 
 T 
 
 
 I 
 
 ■ 1 ! 
 
 1 ' I 1 1,1,1 
 
 
 1 1 1 1 
 
 
 1 1 I i 1 . i 
 
 i t 
 
 i I 1 1 1 J 
 
 ' , i , 
 
 1 i ' 
 
 11 ! 
 
 ■ i ' i « 
 
 i l 
 
 1 I..., ,1 ,.... 
 
 i i 
 
 Grab en 
 
 Ter urology applied to a 
 fault 
 
 Normal or gravity fault 
 
 A : ; -_-s - -Vs 
 
 / \ S. / 
 
 
 
 o c_3 o o o O a V" 
 
 o a a o o o e>\ 
 
 cr c» © o o o ^ 
 
 — _ 
 
 \* • ' . • » • • < 
 
 
 . \i C5> cs (O 
 
 k\\ a ° ° 
 
 
 
 
 -^j 
 
 _3— _\__1 
 
 ^ 
 
 Fault line scarp 
 
 oooa«oooao<=> «=> o o <? 
 
 OOoOOcsOOO o o o <o o 
 
 Thrust fault 
 
COMMON TYPES of ILLINOIS FOSSILS 
 
 Plate 
 
 Cup coral 
 
 GRAPTOLITE 
 
 S9s&#%, 
 
 CRINOID 
 
 PENTREMITE 
 
 Lithostrotion 
 CORALS 
 
 Fenestella 
 
 Honeycomb coral 
 
 Archimedes 
 
 Branching 
 
 BRYOZOA 
 
 Lingula Orbiculoidea 
 
 ml 
 
 »W/f ill* J-4-l.-il ■(,',>■» 
 
 Spiriferoid 
 
 
 Productoid 
 
 Pentameroid 
 
 BRACHIOPODS 
 
Plate 2 
 
 COMMON TYPES of ILLINOIS FOSSILS 
 
 " /*■__ '< 
 
 "Scallop" 
 PELECYPODS 
 
 Coiled cone 
 (Nautilus) 
 
 Straight cone 
 
 CEPHALOPODS 
 
 High- spired 
 
 Bumastus 
 
 Low - spired 
 
 Calymene 
 (coiled ) 
 
 OSTRACODS 
 (greatly enlarged) 
 
 Calymene 
 (flat) 
 
 TRILOBITES 
 
 tag* 
 
TILL PLAINS SECTION, 
 
 GREAT LAKE 
 k J SECTION 
 
 CENTRAL 
 LOWLAND 
 PROVINCE 
 
 CENTRAL 
 
 LOWLAND 
 
 PROVINCE 
 
 INTERIOR 
 LOW 
 
 PLATEAUS 
 PROVINCE 
 
 ILLINOIS STATE GEOLOGICAL SURVEY 
 
 COASTAL PLAIN 
 PROVINCE 
 
 PHYSIOGRAPHIC DIVISIONS OF ILLINOIS 
 
 (Reprinted from Report of Investigations No. 129, Physiographic Divisions of Illinois, 
 by M. M. Leighton, George E. Ekblaw, and Leland Horberg)