BEDROCK GEOLOGY OF WELGE QUADRANGLE Illinois Department of Natural Resources Illinois Geologic Quadrangle Map ILLINOIS STATE GEOLOGICAL SURVEY RANDOLPH AND JACKSON COUNTIES, ILLINOIS IGQ Welge-BG William W. Shilts, Chief W. John Nelson 2007 Mk & e" 175 e" 84 sm o3 h &cv 164k" 170 k" k" 262 ^ ^ þ þüþü þ 2o o &c &s 250 h o 3 250 9 970 e" &cv -1 351e" Sª 00 136 k820 200 k" &t 62 k" 1 5 0 5 -5 N 0 J N 1 123 0 N J 757 0 e" J N N 0 J J N ª J N 0 350 J N oN J k" 87 k" Mc J S 377N 45 J k" 162 136 Mk NJ 165 N k 161 e" e" J 226 N J e" k" N S 677 J k Mk 161 145k" k"161 GS S 849 398 163 N 250 N 55 e" J k k J e" e" e" 142 k"164 172 S 395 143 k" Md S 411 i N k"142 J N N 130 k" ª J J NJ NJ NJ N N S J J N N 486 J J NJ N N J J NJ N 300 ª J N MASTER FAULT, J N &t k"46 COTTAGE GROVE FAULT SYSTEM J NJ N 205 Md 143 J 250 135 k" S k" k" N k" 41 k" k372 J 103 NJ 20 164 " 104 k k" N 0 15 J e" 248 0 EXPLANATION 150 e" e" 138 256 160 e" 5 k" 204k" k" 10 0 449 201 k" 0 350 k" 60 225 k" k"123 211 182 k" J N &cv sm Surface-mined area " k" 142 133 e k" 122 ª 150 k" 150 610 k" 150k" N e" J k" 200 &s Shelburn Formation 205 N k" J 136 k" 15 k" 0 146 142 Mk k" 282 h N k" S J 151e" ª k"153 k" &c Carbondale Formation 759 190 Desmoinesian J G 2165 N N Ü Mp J ª h, Herrin Coal Member N Mc 258 Pennsylvanian J k" N J k"123 N J J &t Tradewater Formation N &cv N J N J &cv N Md 205 J Unconformity k" N 25 J e"175 Md J N 0 J N N N J Morrowan J &cv Caseyville Formation Mps 30 Md N 730 k" J J o G N 152 N J k" N Unconformity N J J 110 " Sk e" k e" S 154 202 " k"164 S 724 e" k k" 129 60 85 123 159 e" Mk Kinkaid Limestone J ª k" N N J k" N 225 J k" S e" 184 450 861 162 " ª k 164 201 &t J 151 N k" k" S 743 k" 150 k" Md Dagonia Sandstone ª 872 145 S 707 ª S 1010 J N k" ª k S 743 280 ª ª GSk734k e" 223 1164 328 k" 795 S 522 Mississippian Mc Clore Formation Chesterian ª 150 250 k" k" 220 ª975 k" 204 338 k" Mp Palestine Formation e" 200 150 0 0 10 15 G 1014 250 Mm Menard Limestone Md Mp ª k" S 1152 103 ª 123 683 k" " k" S e"169 e Mp Md ª 182 1335 k" 124 k" k" 154 394 109 e" Symbols S 748 Md Mm ª 3 Mp &cv Strike and dip of bedding; number indicates degree of dip 180 þþ Mm k" GC ^ ^ ü Joints 0 k" 232 þþ 0 30 35 Outcrop of special note, where unit or contact was well 10 Mc 0 exposed at time of mining. 171 k" Mp Drill Holes S 117 from which subsurface data were obtained ª k" 189 162 190 k" Dry oil - test hole k" 116 ª Md e" &cv k Dry hole - show of oil Mp S k" k" i Dry hole - show of gas k" 206 65 105 Mc e" Engineering boring 230 k" 163 k" e" A Md k" 171 Water well k" Mp 152 e" Stratigraphic borehole k" 126 Sk" Boring with samples (S), geophysical log (G), or core (C). 186 260 k" 15 CSG k 35 200 0 Numeric label indicates total depth of boring in feet. k" 201k" 20 k" Dot indicates location accurate within 100 feet. Mp Mc 0 210 0 300 25 &t Line Symbols e"175 &cv dashed where inferred Mm e" 91 105 222 k" k" k" 133 k" 183 Contact Mk k" 205 Normal fault; bar and ball on downthrown side Mc 250 Structure contours, elevation of top of Menard Limestone, Allard Member in feet; contour Mk 700 Md k 313 G M k" interval 50 feet e" GC k" k 205 k" 437 545 GS k1024 Note: Well and boring records are on file at the ISGS Geological &cv Records Unit and are available from the ISGS Web site. 454 0 e" e" 374 35 Mk Md Md 34 Mk A� 287 1108 k" 182 " e" k ª k" Mc 208 k" Mp Md 232 k"222 &t Mc Mk &cv Mc Sª1000 k" Md 204 248 &cv k" e"421 &cv S k" 20 Mk Md Md &cv &cv Mk Base map compiled by Illinois State Geological Survey from digital data provided by the SCALE 1:24,000 Geology based on field work by J. Nelson, 2005–2006. United States Geological Survey. Topography by photogrammetric methods from aerial 1 1/ 2 0 1 MILE photographs taken 1965. Field checked 1968. Digital cartography by J. Domier, J. Palmer and M. Widener, Illinois State Geological 1000 0 1000 2000 3000 4000 5000 6000 7000 FEET Survey. North American Datum of 1927 (NAD 27) 1 .5 0 1 KILOMETER Projection: Transverse Mercator This geologic map was funded in part by the USGS National Cooperative Geologic Map- 10,000-foot ticks: Illinois State Plane Coordinate system, west zone (Transverse Mercator) ping Program. The views and conclusions contained in this document are those of the 1,000-meter ticks: Universal Transverse Mercator grid system, zone 16 authors and should not be interpreted as necessarily representing the official policies, BASE MAP CONTOUR INTERVAL 20 FEET either expressed or implied, of the U.S. Government. NATIONAL GEODETIC VERTICAL DATUM OF 1929 Recommended citation: The Illinois State Geological Survey, the Illinois Department of Natural Resources, and the Nelson, W.J., 2007, Bedrock Geology of Welge Quadrangle, Randolph and Jackson Coun- State of Illinois make no guarantee, expressed or implied, regarding the correctness of the ties, Illinois: Illinois State Geological Survey, Illinois Geologic Quadrangle Map, IGQ Released by the authority of the State of Illinois: 2007 interpretations presented in this document and accept no liability for the consequences Welge-BG, 2 sheets, 1:24,000, 3-page report. 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. 1° ROAD CLASSIFICATION ADJOINING 123 QUADRANGLES MA TR 1 Walsh GNETIC NOR Primary highway, Light-duty road, hard or UE NOR 2 Steeleville hard surface improved surface 3 Percy 45 Secondary highway, 4 Chester TH hard surface Unimproved road 5 Willisville T For more information contact: H 6 Belgique Illinois State Geological Survey 678 7 Rockwood 615 East Peabody Drive 8 Raddle APPROXIMATE MEAN State Route Champaign, Illinois 61820-6964 DECLINATION, 2007 (217) 244-2414 http://www.isgs.uiuc.edu IGQ Welge-BG Sheet 1 of 2 Outcropping and Subcropping Strata THICKNESS A Carbondale Formation Shale, siltstone, sandstone, limestone, deposition occurs between basal Tradewater (early Desmoinesian) and gang bands are present but less conspicuous than in the Caseyville. FORMATION MEMBER GRAPHIC COLUMN (FEET) coal, and claystone. Shale is medium to dark gray, clayey to silty, mica- Caseyville (presumably Morrowan) strata of the map area. Apparently Degonia sandstone is well-sorted, very fine to fine quartz arenite that UNIT SERIES SYSTEM ceous, carbonaceous, and sideritic. Siltstone is light to medium gray, the entire Atokan series is missing in the study area. contains scattered shale rip-up clasts but no quartz granules. The rock Herrin Coal 6 quartzose, micaceous, and carbonaceous. Sandstone is light to medi- is permeable and partly calcareous, laminated to massive. Planar, um gray, very fine- to medium-grained lithic arenite, with plentiful mica C Caseyville Formation Sandstone, siltstone, shale, and conglom- ripple, flaser, and micro-cross-laminations are commonly rhythmic, 15–20 Springfield Coal and carbonaceous debris. Shale, siltstone, and sandstone commonly erate. Sandstone is white to light gray (fresh), weathering yellow to suggestive of tidal activity. Trough cross-bedding occurs in sets a few 4–5 are interlaminated and interbedded. Clastic intervals commonly coars- orange and dark brown and forming prominent cliffs and ledges. Out- inches to about 2 feet thick and shows northeast to northwest paleo- en upward. Black, fissile, phosphatic shale units overlie the Colchester crops can be heavily encrusted by iron oxide and display Liesegang currents; some outcrops have bidirectional cross-bedding. Along Mill 40–65 and Houchin Creek Coals. Limestone is light to dark gray, argillaceous bands. The sandstone is quartz arenite that ranges from very fine- to Creek in the southeastern part of the map area, tabular planar cross- lime mudstone to skeletal wackestone and packstone. Coal is bitumi- very coarse-grained and commonly contains well-rounded quartz bedding in sets as thick as 6 feet shows paleocurrents directed south, nous and bright-banded, with laminae of claystone, fusain, and pyrite.