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Bedrock Geology of Herod Quadrangle

BEDROCK GEOLOGY OF HEROD QUADRANGLE

ILLINOIS STATE GEOLOGICAL SURVEY POPE, SALINE, AND HARDIN COUNTIES, STATEMAP Herod-BG E. Donald McKay III, Interim Director F. Brett Denny, W. John Nelson, and Joseph A. Devera 2008

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Normal fault; bar and ball on downthrown side Base map compiled by Illinois State Geological Survey from digital data (Raster Feature SCALE 1:24,000 Geology based on field work by F. Brett Denny, W. John Nelson, and Joseph A. Devera, ( ( Separates) provided by the United States Geological Survey. Topography compiled 1957. 1 1/ 2 0 1 MILE 2007–2008. Thrust fault Planimetery derived from imagery taken 1993. Public Land Survey System and survey 1000 0 1000 2000 3000 4000 5000 6000 7000 FEET control current as of 1996. Partial field check by U.S. Forest Service 1996. Digital cartography by Jane E.J. Domier, Brendon M. Aitken, and Steven M. Radil, Illinois A A� Line of cross section 1 .5 0 1 KILOMETER State Geological Survey. North American Datum of 1927 (NAD 27) Projection: Transverse Mercator This research was supported in part by the U.S. Geological Survey National Cooperative Note: Well and boring records are on file at the ISGS Geological 10,000-foot ticks: Illinois State Plane Coordinate system, east zone (Transverse Mercator) Geologic Mapping Program (STATEMAP) under USGS award number 07HQAG0109. The Records Unit and are available online from the ISGS Web site. 1,000-meter ticks: Universal Transverse Mercator grid system, zone 16 BASE MAP CONTOUR INTERVAL 20 FEET views and conclusions contained in this document are those of the authors and should not NATIONAL GEODETIC VERTICAL DATUM OF 1929 be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Government.

Released by the authority of the State of Illinois: 2008 The Illinois State Geological Survey and the State of Illinois make no guarantee, ex- pressed or implied, regarding the correctness of the interpretations presented in this document and accept no liability for the consequences of decisions made by others on the basis of the information presented here. The geologic interpretations are based on data that may vary with respect to accuracy of geographic location, the type and quantity of data available at each location, and the scientific and technical qualifications of the data sources. Maps or cross sections in this document are not meant to be enlarged.

2° ROAD CLASSIFICATION ADJOINING 123 QUADRANGLES MA TR 1 Harrisburg NOR GNETIC Secondary highway, Light-duty road, dirt UE NOR UE 2 Rudement hard surface 3 Equality Light-duty road, dirt 45 Light-duty road, hard or

4 Eddyville TH improved surface For more information contact: Unimproved road

5 Karbers Ridge T Illinois State Geological Survey 6 Waltersburg H 615 East Peabody Drive 678 7 Shetlerville Champaign, Illinois 61820-6964 8 Rosiclare APPROXIMATE MEAN State Route County Route (217) 244-2414 DECLINATION, 2008 http://www.isgs.uiuc.edu

STATEMAP Herod-BG Sheet 1 of 2 MEMBER THICKNESS A Permian Igneous Intrusives Ultramafic dike, lamprophyre, autolithic brec- M Hardinsburg Sandstone Sandstone, siltstone, and shale. Sandstone is FORMATION or GRAPHIC COLUMN (feet) cia, diatreme, and sills. The igneous intrusions form dikes, sills, and pipes. The light gray to buff, very fine to medium-grained quartz arenite that is thinly bedded BED UNIT

SERIES dikes occur with a light-gray sugary texture or as a dark greenish-black (ultrama- to massive. Ripple marks and crossbedding are common. Siltstone and shale SYSTEM fic) with an inequigranular porphyritic texture. The light-gray dikes are classified are medium to dark gray or greenish gray, ripple marked and laminated. The x x dike x diatreme x as lamprophyre. These rocks are dominantly composed of carbonate, but few lower contact is generally unconformable with the underlying unit. Igneous dikes x x PERMIAN LEON- and ARDIAN & breccia sill x breccia x ? A microscopic examinations of this rock has been accomplished. The ultramafic x x x x x rock contain serpentine (altered from olivine), apatite, phlogopite, titanite, chro- N Golconda Formation Limestone, shale, mudstone. The formation is divided mite, magnetite, chlorite, perovskite, garnet, and calcite are commonly found in into three members. The Haney Limestone Member at the top is largely light to +60 association with the light gray lamprophyres. The autolithic breccia is composed dark gray, fine to coarse crinoidal wackestone to cross bedded grainstone, and of country rock or wall rock incorporated into the circular pipe during the intru- in places oolitic. The lower part of the Haney comprises limestone and shale in- sions vertical ascent. It may have a siliceous or carbonate rich matrix. Where the terbedded in roughly equal proportions which grade into the underlying Fraileys Mitchellsville Ls. 2–5 pipes contain rounded autolithic clasts and not angular breccia clasts, the pipes Shale Member. The Fraileys Shale Member is largely olive to greenish-gray to may be described as diatremes. These intrusive magmatic bodies are thought dark gray, calcareous, thinly fissile clay shale, with limestone beds of varied tex- golden ss. to be related to a single geologic event of a gas-rich alkalic magma originating ture as thick as several feet. Red shale or mudstone may occur near the top. The New Burnside & 0–2 Delwood coals from the upper mantle. Fluorite was observed enclosed within an ultramafic rock Member at the base is dark gray to brown, partly dolo- DESMOINESIAN indicating a genetic relationship between these intrusions and the fluorite miner- mitic, argillaceous limestone. The lower contact is sharp with the underlying unit. Tradewater B alization of this region.

ANIAN O Cypress Sandstone Sandstone, shale, and siltstone. The sandstone is

Oldtown coal 0–3 V Murray Bluff Ss. B Tradewater Formation Sandstone, siltstone, shale, conglomerate, and coal. white to light gray fine to medium grained subangular quartz sandstone. The up- The sandstones are composed of white to tan-brown fine to coarse grained per portion contains thin beds of siltstone and interbedded sandstone and shale.

50–110 300–450 quartz arenite and sublithic arenite. Mica is usually present and a small percent- The lower portion is primarily thick beds of sandstone. A red and green shale

age of clay is present in the sublithic arenites. Sandstones are cross bedded may be present near the top of the formation. Locally the contact with the under- PENNSYL

and ripple marked. Ichnofossils are common and include both burrowing and lying unit is unconformable. OKAN

90–150 feeding or grazing patterns. The siltstone are gray and mica may be present on AT the bedding surfaces. The shale is gray to black and thinly bedded. The few con- P Ridenhower Formation Shale, limestone, and sandstone. The shale is dark Reynoldsburg 0–2 coal glomerate layers were probably reworked quartz pebbles from the underlying gray with a green tint and may be fossiliferous. It is thin bedded and silty to finely Caseyville Formation into which the lower portion of this unit incises. Thin and sandy. Several feet of limestone may be present at the top of this formation. This

AN discontinuous coal seams are reported in this unit. The Tradewater is uncon- unit is highly variable but is dominantly a dark gray shale with interbeds of gray-

OW formable with the underlying Caseyville but where the lower quartz arenite is de- green siltstone. Caseyville 200–300 C posited over an upper Caseyville quartz arenite it is difficult to define the contact.

MORR Q Bethel Sandstone Sandstone with minor shale. White to light gray, fine to C Caseyville Sandstone, shale, siltstone and conglomerate. The sandstone coarse grained quartz sandstone. The shale occurs as greenish thin interbeds Kinkaid 0–100 D is usually a white to gray on fresh surfaces and weathers to a brown or orange- between thicker beds of sandstone. Near the base shale and quartz pebbles Limestone brown. It is composed of well rounded to sub angular coarse to medium grained may be present indicating this unit is locally unconformably with the underlying Degonia Sandstone 0–30 E quartz “ quartz arenite” that has a sugary appearance. It may be cross bedded formation. Ford Station Ls. and also occurs in thin beds and massive ledges. Outcrops are usually well ex- Clore Tygett Sandstone 100–120 F posed bluffs showing diverse fluvial and tidal patterns including stacking chan- R Downeys Bluff Limestone Limestone, dolostone, shale, chert. The lime- Cora Limestone nels, unidirectional and bidirectional cross beds. Iron bands “liesegang” may stone is light gray crinoidal grainstone while the dolostone is brownish gray. be very common in some sandstone outcrops. Occasional plant remains such Disarticulate crinoids may be replaced by pink chert, which is diagnostic for this Palestine 50–60 G as stimgeria are present but are rare in the sandstone and are more common unit. The upper portion is generally cherty while the lower may be silty. Shale oc- within the shale. The shale is dark gray laminated to thinly bedded. Plant debris curs in thin interbeds and composes a minor portion of the unit. Menard 100–130 H is common and iron nodules or concretions may be present. Siltstone occurs as Limestone thin beds usually with the shale. Conglomerates occur as shale pebbles within S Yankeetown Formation Shale, limestone, siltstone. The shale is dark gray sandstone and more common quartz pebble within a coarse quartz sand. The to green fossiliferous shale with interbedded dolomitic siltstone and thin beds of Waltersburg 30–40 I quartz pebbles are very well rounded and usually white. They quartz pebbles limestone. The contact with the underlying unit is gradational. 10–20 J may be several inches in diameter. This unit is unconformable with the underly- Tar Springs 70–100 K ing unit. T Renault Limestone Limestone, siltstone, shale. The Renault is dominantly Sandstone a fossiliferous light gray to brown-gray sandy to oolitic limestone. The siltstone is Glen Dean 40–70 L D Limestone, shale, and mudstone. Where this unit is coarse grained, calcareous, and occurs near the base. The shales are calcare- Limestone well developed it consists of three members which in descending order are ous and interbedded with limestone and siltstone. Hardinsburg Goreville Limestone, Cave Hill, and Negli Creek. This unit is eroded by Lower 90–115 M Sandstone Pennsylvanian units and may be entirely missing in portions of the quadrangle. U Aux Vases Sandstone, shale, siltstone. The sandstone is light green-gray The Goreville is a packstone to lime mudstone with a few thin shale breaks. It fine grained and ripple marked. The sandstone beds are thin to medium with the Haney Limestone contains diverse marine including fenestrate, trepostome, and fistuliporid thicker beds usually being cross bedded. Siltstones are also greenish-gray and Golconda Fraileys Shale 100–140 N bryozoans, spiriferids and other brachiopods, rugose corals, and crinoids. The interbedded with the sandstone and dark gray shale. This unit is locally mapped

CHESTERIAN Beech Creek Ls. bryozoan Archimedes can be abundant in the upper beds and pterotocrinus as the Rosiclare Member of the Aux Vases Formation. Some of the sandstone wing plates have been described and studied in the formation (Gutschick, 1965). may be calcareous and this grades into the underlying limestone. Cypress 80–100 O The Cave Hill is composed of shale and mudstone with thin beds of limestone. Sandstone The shale is dark gray, soft, fissile, calcareous, and may be laminated. The shale V Ste. Genevieve Limestone Limestone, dolostone, shale, chert. The lime- may grade to limestone which mainly lime mudstone. The negli Creek is primari- stone is light gray to medium gray, oolitic to micritic and sandy in places. Beds Ridenhower 25–65 P ly a dark gray lime mudstone to wackestone. Fossils include brachiopods, fenes- are thick to thin bedded and the oolitic beds are usually cross bedded. A sandy trate bryozoans, blastoids, bellerophontid gastropods, and Girvanella spheriods. limestone “Spar Mountain Member” is locally present about 60 feet below the Bethel 80–100 Q The lower contact is generally sharp but rarely well exposed. base of the Aux Vases Formation (Baxter et al., 1967). The dolomite is fine Sandstone grained and the shale is gray. It is composed of a diverse marine fauna with Downeys Bluff Ls. 25–35 R E Shale, sandstone, siltstone. The Degonia is largely crinoidal debris being the most common. Chert is a minor and much more com- shale that is dark gray to greenish gray, partly silty and moderately to highly fis- mon in the underlying St. Louis Limestone below. The unit is gradational with the Yankeetown Ss. 15–30 S sile. Greenish gray siltstone to silty mudstone in the middle of the Degonia may underlying limestone. Renault Ls. Shetlerville 15–35 be massive. Sandstone is light brown, very fine grained, clean quartz arenite Levias T with thin wavy bedding and ripple marks. More distinctive is very fine sandstone W St. Louis Limestone Limestone, dolostone, shale, chert. The limestone is Aux Vases Ss. Rosiclare 15–40 U to siltstone that is dark olive to greenish gray, weathering rusty orange. This rock medium to dark gray crystalline to micritic. The unit is cherty with gray to blue- has planar lamination and erodes out as long rectangular and wedge-shaped gray chert nodules along bedding planes. It contains a diverse marine fauna in- Ste. Genevieve blocks bounded by joints. The unit is poorly exposed and is mapped together cluding brachiopods, crinoids, and corals. Shales are thin and separate the thick 150–200 V Limestone with the underlying Clore Formation. The contact with the Clore is sharp to gra- limestone and dolostone beds. dational.

X Salem Limestone Limestone, dolomite, chert, siltstone, and shale. The MISSISSIPPIAN F Clore Formation Limestone, shale, sandstone, siltstone, and chert. Salem Limestone is light brown to very dark gray mudstone to grainstone com- are mainly lime mudstone which are several feet thick, medium- posed of rounded and broken fragments. Bedding styles range from tabu- dark gray to olive gray and weather to a light gray or orange-brown. Spiriferids, lar to undulatory. The beds range from several inches to a few feet thick. The unit productid, and compositid brachiopods are common. The Ford Station Member is composed primarily of small rounded fragments of disarticulated echinoderms St. Louis is dark gray, calcareous, and fossiliferous, ranging from a platy clay shale to and fenestrate bryozoans that are abraded into a fossil hash. Other macro fos- 300–400 W Limestone silty shale having laminae and thin interbeds of light gray siltstone. The Tygett sils are corals, brachiopods, and Pentremites. Peloidal to oolitic limestone is also Sandstone Member is light gray to light brown, very fine to medium-grained present, and portions may be dolomitic. Chert is light gray, may be bioclastic, quartz arenite. The sandstone becomes thin-bedded with wavy ripple-marked and may weather with a porous rind. Siltstone is brown to light gray and thinly bedding surfaces. Laminated sandstone in turn grades downward to siltstone bedded, typically less than 1 inch thick. The shale is blue-gray to green-gray. The and shale. The Cora Limestone Member contains thin beds and lenses of contact with the underlying unit is unconformable but difficult to identify. highly fossiliferous limestone and greenish gray, silty, and weakly fissile shale or mudstone. Limestone bed at the top is dark gray, very argillaceous brachiopod- Y Ullin Limestone Limestone, shale, chert. The limestone is light gray with bryozoan lime mudstone to wackestone that weathers yellowish gray. The lower dark gray fossil grains and appears to be speckled. The appearance is due to contact is sharp. disarticulate bryozoan debris and the white “chalky” calcite cement or matrix. This texture is diagnostic for this unit, but the unit is poorly exposed in the quad- Salem G Palestine Formation Sandstone, siltstone, shale, mudstone, minor coal. rangle. The Ullin is conformable with the underlying unit. 425–525 X Limestone Sandstone is light gray to white, very fine to fine quartz arenite. In most places the upper part is cross bedded and the lower portion having thin, flaggy and rip- Z Fort Payne Formation Limestone, siltstone, chert. The limestone is fine ple-marked bedding. Siltstone is dark olive gray, thinly laminated. Carbonaceous grained, dark gray, very cherty and siliceous. It also contains light gray siltstone

black shale and coal was observed at the top of the Palestine overlying a rooted interbedded with shale. The unit has been altered and silicified and few if any ALMEYERAN

V siltstone grading into laminated shaly sandstone. macro fossils are observable. Outcrops near Hicks Dome are composed of very cherty iron rich siliceous fractured limestone. An outcrop of this unit along Hicks Harrodsburg H Menard Limestone Limestone and shale. The upper limestone is called the Branch include a non-calcareous siliceous residuum with interbeds of clay. Allard Limestone Member. It is usually a gray lime mudstone and fine to coarse Ullin 125–200 Y skeletal wackestone and packstone with thin shale interbeds and scattered chert AA Springville Shale Shale and clay. The shale is green-gray clay shale. The Limestone nodules. The Scottsburg Limestone Member, is a light to dark gray limestone, only exposure of this unit observed in the quadrangle was along Hicks Branch. Ramp Creek sublithographic lime mudstone separated by thin shale layers. The lowest mem- ber is the Walche Limestone Member, which is composed of argillaceous micritic BB Chouteau Limestone Limestone. The unit is a medium green-gray micritic limestone. Fossils within the Menard include the brachiopods, bryozoans, and limestone. The only exposure of this unit observed in the quadrangle was along disarticulate crinoidal debris. Hicks Branch. Fort Payne 300–500 Z I Waltersburg Formation Sandstone, shale, siltstone. The unit is mainly CC Hannibal Shale Shale and siltstone. The unit is a thin gray-green siltstone dark gray, thin clay shale that becomes silty upward and grades into siltstone. and shale. The only exposure of this unit observed in the quadrangle was along Sandstone is olive gray to brownish gray, very fine grained, shaly, and thinly bed- Hicks Branch. ded. Thin coal and greenish shale may be present near the top of this unit. Springville Shale 10–30 AA DD New Albany Shale Shale and siltstone. This unit is divided into three KINDER- Chouteau Ls. 0–10 BB J Vienna Limestone Limestone, shale, and chert. Limestone is largely dark members which in ascending order are the Sweetland Creek Shale Member, HOOKIAN Hannibal Shale 0–20 CC gray to brownish gray, siliceous lime mudstone and wackestone. A few thin in- Grassy Creek Shale, and the Saverton Shale. The shales are black to green- terbeds of sandy dark-gray shale are present. Dark brown chert nodules are ish and blueish-gray fissile shale that may be either silty or calcareous. Some of Saverton Shale numerous and commonly weather with a porous rind. The white to brown weath- the more calcareous layers may grade into argillaceous limestones, but these ered, porous blocks of fossiliferous chert are diagnostic. are thin and rare. The unit is dominantly a black fissile shale with pyrite and few

y Shale Grassy Creek observable macro fossils. Good exposures of this units are present along a tribu-

Shale 300 DD K Tar Springs Sandstone Sandstone, siltstone, shale, thin coal. Sandstone tary of Hicks Branch. ONIAN

UPPER is white to light gray and greenish gray, very fine to medium-grained quartz w Alban

DEV that is slightly micaceous. It varies from thinly bedded to massive and displays EE St Laurent Cherty and siliceous limestone and dolostone. The unit was

Ne Sweetland Creek Shale ripple marks, crossbedding, small load casts, indistinct burrows, and shale rip- originally limestone but has been mostly silicified to a cherty or siliceous re- up clasts. Shale and siltstone are medium to dark gray, micaceous, and thinly siduum at the surface. Subsurface data indicate the unit is a cherty argillaceous laminated. Thin coal commonly occurs near the top; it rests on dark gray, rooted limestone. St. Laurent 70–100 EE mudstone. Dark gray claystone also occurs in the lower Tar Springs. The lower

ONIAN contact is sharp in some localities but may grade into the underlying unit. FF Grand Tower Cherty limestone and dolostone. The unit is dominated by

light gray lithographic and siliceous limestone. DEV ONIAN Grand Tower 140–200 L Glen Dean Limestone Limestone and shale. The unit is generally com- MIDDLE FF Limestone

DEV posed of an upper limestone a middle shale and a lower limestone. The upper GG Cherty limestone and dolostone. The chert is light limestone is medium to dark gray crinoidal packstone and grainstone and may gray to white and the limestone has been altered to a siliceous porous rock with be oolitic. Fossils include crinoidal debris, fenestrate bryozoans, brachiopods, clasts of brachiopods. blastoids, and corals. The middle shale is thin medium to dark gray and greenish gray, fossiliferous, and calcareous. The middle shale beds grade into the lower Clear Creek

WER +200 ONIAN GG limestone. The lower contact appears to be gradational.

Chert

LO DEV

Northwest Southeast A A� Wamble Elevation Mountain (feet) King #1 Rose Shawneetown Texaco Oil Herod Fault Creek Zone Fault Zone &cv Co. (Dry) Horton Hill Mine 1000 Mk Anticline Pinhook 1000 Rose Creek Hicks Dome Mk Creek Mdc Mp Mwvt Mav Mp Mp Mk Mm Mcy Mrb Mdyr &cv &cv Mp Mgd Mm &t Mu Mgd Mwvt Mdc Mh Msg Mh Mdc Mm Mg Mk ? Mg Mwvt Mgd Mrb Msl 0 &cv Mcy 0 Mrb Mh Mdyr Msm Mk Mdyr Mg Mav Mcy Msg Mu Mdc Mav Msg Mrb Mdyr Mfps Mp Msg Mav Msl Mm Msl Mgd Mwvt Msl Msm MDcn -1000 Mh Msm -1000 Mg Mu Mcy Mu Msm Mrb Mu Mfps Mdyr Mav Msg Mfps Du Mfps Msl MDcn ? -2000 MDcn -2000 Msm MDcn

Mu Du Du Total depth Du Mfps 3,172 feet ? MDcn -3000 -3000

Waltersburg, Downeys Bluff, Fort Payne Devonian undifferentiated Horizontal scale: 1 inch = 2,000 feet Tradewater Kinkaid Palestine Hardinsburg Cypress Ste. Genevieve Salem &t Mk Mp Mwvt Vienna, and Tar Mh Mcy Mdyr Yankeetown, and Msg Msm Mfps and Springville Du St. Laurent, Grand Tower, Vertical scale: 1 inch = 1,000 feet Formation Limestone Formation Sandstone Sandstone Limestone Limestone Springs Formations Renault Formations Formations and Clear Creek Formations Vertical exaggeration: 2�

Ridenhower Chouteau and Caseyville Degonia and Menard Glen Dean Golconda Aux Vases St. Louis Ullin &cv Mdc Mm Mgd Mg Mrb and Bethel Mav Msl Mu MDcn New Albanay Formation Clore Formations Limestone Limestone Formation Sandstone Limestone Limestone Formations Formations

STATEMAP Herod-BG Sheet 2 of 2

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