BEDROCK TOPOGRAPHY OF WATERLOO...
Transcript of BEDROCK TOPOGRAPHY OF WATERLOO...
Illinois Geologic Quadrangle MapIGQ Waterloo-BT
Base map compiled by Illinois State Geological Survey from digital data provided by the United States Geological Survey. Topography compiled by photograpmmetric methods from aerial photographs taken 1986. Planimetry derived from imagery taken 1998. PLSS current as of 1989.
North American Datum of 1983 (NAD 83)Projection: Transverse Mercator10,000-foot ticks: Illinois State Plane Coordinate system, west zone (Transverse Mercator)1,000-meter ticks: Universal Transverse Mercator grid system, zone 15
Recommended citation:Panno, S.V., F.B. Denny, J.C. Angel, and J.E. Crockett, 2008, Bedrock Topography of
Waterloo Quadrangle, Monroe County, Illinois: Illinois State Geological Survey, Illinois Geologic Quadrangle Map, IGQ Waterloo-BT, 1:24,000.
Based on field work and data compilation by S. Panno, B. Denny, and J. Angel, 2007.
Digital cartography by J. Domier, S. Geegan, and S. Radil, Illinois State Geological Survey.
The Illinois State Geological Survey, the Illinois Department of Natural Resources, and the State of Illinois make no guarantee, expressed 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.
IGQ Waterloo-BT
BEDROCK TOPOGRAPHY OF WATERLOO QUADRANGLEMONROE COUNTY, ILLINOIS
Samuel V. Panno, F. Brett Denny, Julie C. Angel, and Joan E. Crockett2008
MA
GN
ET
IC
NO
RT
H
APPROXIMATE MEANDECLINATION, 2008
TR
UE
N
OR
TH
/ °1 2ROAD CLASSIFICATION
Primary highway,hard surface
Secondary highway,hard surface
Light-duty road, hard orimproved surface
Unimproved road
State Route
ADJOINING QUADRANGLES1 Oakville2 Columbia3 Millstadt4 Valmeyer5 Paderborn6 Selma7 Renault8 Ames
BASE MAP CONTOUR INTERVAL 10 FEET
NATIONAL GEODETIC VERTICAL DATUM OF 1929
For more information contact:Illinois State Geological Survey 615 East Peabody Drive Champaign, Illinois 61820-6964 (217) 244-2414 http://www.isgs.uiuc.edu
1 2 3
4 5
6 7 8
Released by the authority of the State of Illinois: 2008
7000 FEET1000 10000 2000 3000 4000 5000 6000
.5 1 KILOMETER1 0
SCALE 1:24,0001/ 21 0 1 MILE
Illinois Department of Natural ResourcesILLINOIS STATE GEOLOGICAL SURVEY
William W. Shilts, Chief
IntroductionThe bedrock topography of the Waterloo Quadrangle is part of a series of maps by the Illinois State Geological Survey (ISGS) that interpret (at a scale of 1:24,000) the geology within 7.5-minute quadrangles in the Metro East Illinois area of Greater St. Louis. Data collection and interpretation were funded by the ISGS.
The Waterloo Quadrangle is an area presently experiencing rapid population growth and urban and suburban development of primarily rural and agricultural land. Because of increasing environmental concerns with karst and associated groundwater contamination issues, it is important to document the bedrock topography for urban planning, land use planning, and water resource management.
The Waterloo Quadrangle lies within the southwestern Illinois sinkhole plain, which is within the Salem Plateau Section (Leighton et al. 1948). The karst topography that dominates the study area is the result of the soluble nature of the underlying bedrock. Mississippian-age carbonate bedrock, particularly St. Louis and Ste. Genevieve Limestones, contain solution-enlarged secondary fractures, and the area is characterized by cover-collapse sinkholes, caves, and large springs.
Map UseThis map is useful for delineating the locations of buried bedrock valleys and for defining flow patterns and recharge and discharge pathways of these aquifers. The map is essential for accurate assessment of the volume and distribution of economically significant shallow deposits of limestone and other construction stone. It is a useful predictive guide for drilling operations, construction and engineering projects, and geophysical surveys and as a base map from which geological units and bedrock structures can be delineated. This bedrock surface is the lower limiting surface that must be integrated into three-dimensional models of the overlying Quaternary sediments. Finally, this bedrock surface is the lower limiting surface that must be integrated into three-dimensional models of the overlying Quaternary sediments.
Mapping MethodsBedrock topography was compiled using data from 335 well logs from the ISGS wells and borings database. Well locations were verified using plat books. Bedrock exposures were used to identify bedrock surface elevations; such exposures were usually associated with the bottom of sinkholes, cave entrances, springs, bluffs along major stream valleys, and stream bottoms. The data were plotted and contoured by hand; the resultant map was scanned into raster format and digitized using ESRI ArcMap software. Bedrock elevations were subtracted from standard 30-m digital elevation model data to be sure that the bedrock surface did not extend above the land surface. Because of the low data density, contour lines were not modified in the vicinity of sinkholes.
Bedrock Topography, Geology, and HydrogeologyThe Waterloo Quadrangle is on the western margin of the Illinois Basin, and the bedrock dips gently to the east. Much of Monroe County and parts of St. Claire County to the north and Randolph County to the south are referred to as the sinkhole plain because of the area’s high density of sinkholes. Approximately 10,000 sinkholes (with densities as high as 230 per square mile), numerous large springs, and the largest caves in the state are found in the Salem Plateau Section (Panno and Weibel 1996, Weibel and Panno 1997, Panno et al. 2004). Glacial drift thickness in this area is relatively thin and typically ranges from 0 to 30 feet (Herzog et al. 1994). Bedrock is covered by a layer of windblown loess that overlies Illinoian glacial deposits and pre-Illinois Episode residuum. This material, especially loess, is easily eroded and forms numerous cover-collapse sinkholes (sinkholes formed in sediment overlying creviced bedrock) and steep-sided gullies. Sinkholes have formed in about 30 feet of loess and glacial sediments over crevices in the bedrock surface that are 6 or more inches wide (Panno et al. 2008). As noted earlier, the quadrangle lies within the sinkhole plain of southwestern Illinois (Panno et al. 1997, Weibel and Panno 1997). The karst topography that characterizes the region is the result of the soluble nature of the underlying bedrock (particularly the St. Louis and Ste. Genevieve Limestones) and the moderate amount of annual precipitation (40 inches per year) of the area. Sinkholes have formed in about 30 feet of loess and glacial sediments over crevices in the bedrock surface that are 6 or more inches wide (Panno et al. 2008). Bedrock exposures in the quadrangle are most often associated with sinkholes, cave entrances, large springs, and along the bluffs overlooking Fountain Creek and streambeds. Most sinkholes, caves, and large springs occur in the Mississippian-age St. Louis and Ste. Genevieve Limestones; these fairly soluble rocks are responsible for widespread karst terrain in southwestern Illinois (Weibel and Panno 1997), Kentucky, and Indiana.
The structural features of the Waterloo Quadrangle are dominated by two subparallel elongate ridges associated with the Waterloo-Dupo Anticline in the northeastern portion of the map and the Valmeyer Anticline in the southeastern portion of the quadrangle (Nelson 1995; unpublished mapping by F.B. Denny). The bedrock topography of the quadrangle is generally reflected in the surface topography and is controlled by bedrock lithology and structures. The bedrock topographic ridge in the northeastern quarter of the quadrangle, identified by contour lines greater than 650 feet above mean sea level, is a result of the Waterloo-Dupo Anticline located slightly to the west. The ridge apparently formed as a result of differential erosion of carbonate rocks on the flanks of the anticline. Highway 3 runs in a northwestern trend along the ridge, and where the ridge gently flattens, the highway curves to the southeast. Those constructing the highway apparently followed the ridge in order to avoid sinkhole areas.
The broad valley of Fountain Creek transects the quadrangle from northwest to southeast. Tributaries drain the highs on the crests of the ridges into Fountain Creek. Bedrock lithology in the Waterloo Quadrangle is made up predominantly of St. Louis and Ste. Genevieve Limestones; these areas are characterized by karst terrain. Bedrock along the crest of the Waterloo Anticline is eroded to the Keokuk and Burlington Limestones, Warsaw Shale, and Salem Limestone. Just to the west of the anticline, Pennsylvanian rocks and the Aux Vases and Renault Limestone constitute the bedrock surface. Aux Vases Sandstone and Renault Limestone are found along the very eastern edge of the quadrangle as well (unpublished mapping by F.B. Denny). Karst features are typically not observed in these latter areas.
The region west of the Waterloo-Dupo Anticline is transected by Fountain Creek. Bedrock topography within the structural low along Fountain Creek descends to lower than 400 feet above mean sea level. The creek and its tributaries occupy the central portion of the quadrangle and are bounded by the ridge of the Waterloo-Dupo Anticline to the north and the Valmeyer Anticline to the southwest. The Columbia Syncline structure parallels the Waterloo-Dupo Anticline structure on its western limb, and this topographic low may be related to the development of the Fountain Creek drainage system. Early workers (Lamar 1922, Weller and Weller 1939) suggested that the steep dip of the western limb of the Waterloo-Dupo Anticline is actually a fault, as did J.A. Devera (unpublished mapping) and F.B. Denny (unpublished mapping). Flat-lying Pennsylvanian rocks form the uppermost bedrock within the Columbia Syncline. Pennsylvanian rocks rest in angular unconformity on the steeply dipping, older Mississippian age rocks of the syncline, and Pennsylvanian age rocks are absent on the crest of the Waterloo-Dupo Anticline (Nelson 1995). The Valmeyer Anticline to the southwest is generally defined by a bedrock ridge where the bedrock topography is greater than 650 feet above mean sea level.
ReferencesHerzog, B.L., B.J. Stiff, C.A. Chenoweth, K.L. Warner, J.B. Sieverling, and C. Avery, 1994,
Buried bedrock surface of Illinois: Illinois State Geological Survey, Illinois Map 5, 1:500,000.
Lamar, J.E., 1922, Notes on the Waterloo Anticline: Transactions of the Illinois State Academy of Science, v. 15, p. 398–404.
Leighton, M.M., G.E. Ekblaw, and C.L. Horberg, 1948, Physiographic divisions of Illinois: Journal of Geology, v. 56, p. 16–33.
Nelson, J.W., 1995, Structural features in Illinois: Illinois State Geological Survey, Bulletin 100, 144 p.
Panno, S.V., J.C. Angel, D.O. Nelson, C.P. Weibel, and J.A. Devera, 2008, Sinkhole density of Waterloo Quadrangle, Monroe County, Illinois. Illinois State Geological Survey: Illinois Geologic Quadrangle Map, IGQ Waterloo-SD, 1:24,000, report, 6 p.
Panno, S.V., S.E. Greenberg, C.P. Weibel, and P.K. Gillespie, 2004, Guide to the Illinois Caverns State Natural Area: Illinois State Geological Survey, GeoScience Education Series 19, 106 p.
Panno, S.V., and C.P. Weibel, 1996, Karst regions of Illinois: Illinois State Geological Survey, Open File Series 1997-2, 42 p.
Panno, S.V., C.P. Weibel, and W. Li, 1997, Karst regions of Illinois: Illinois State Geological Survey, Open File Series 1997-2, 42 p.
Weibel, C.P., and S.V. Panno, 1997, Karst terrains and carbonate bedrock of Illinois: Illinois State Geological Survey, Illinois Map 8, 1:500,000.
Weller, S., and J.M. Weller, 1939, Preliminary geological maps of the pre-Pennsylvanian formation in part of southwestern Illinois: Illinois State Geological Survey, Report of Investigations 59, 15 p.
Bedrock Elevation(feet above mean sea level)
700
750
650
600
550
500
450
400
350
H
H
HH
"e615
Note: Well and boring records are on file at the ISGS Geological Records Unit and are available from the ISGS Web Site.
Water-well boring, bedrock elevation in feet above mean sea level
Normal fault: bar and ball on downthrown side, inferred
Syncline
Anticline
Data Type
650
690
660
450
500
730
550
630
630
650
650
650
700
600
550
650
660
680
670
600
720
680
600
630
600
550
500
590
670
680
650
620
750
660
640
640
550
580
690
620
600
640
720
550
650
700
690
650
680
650
690
650
700
700
600
500
670
650
600
600
550
650
660
580
500
590
600
680
550
670
720
600
600
620
650
630
430
650
500
680
670
650
650
750
620
600
700
530
630
590
600
660
550
670
450
640
630
560
600
700
670
600
620
650
580
740
600
700
700
450
680
450
500
640
500
650
730
650
600
690
660
650
710
750
650
740
730
650
600
740
570
520
670
630
640
700
620
660
640
7
98
5
987
346 2
8
1
87
6
7
5
30
11
17
31
10
10
13
16
26
28
22
2527
2527
32
28
23
29
24
29
21
11
21
33
14
29
20
26
15
15
12
14
32
30
22
19
18 17
20
1718
20
29
20
12
19
18
16
24
36
17
23
34
18
19
35
30
30
13
31
19
620
T. 3 S.
T. 2 S.
T. 3 S.
T. 2 S.
R. 9 W.R. 10 W.
R. 10 W. R. 9 W.
156
156
3
156
3
90°15'38°22'30"
90°15' 480000 FEET
580000FEET
12' 30" 10'
12' 30" 10'
38°15'
17'30"
20'
17'30"
20'
38°15'
38°22'30"90°07'30"
90°07'30"
4250000m.N.
4238000m.N.
4249
4248
4247
4246
4245
4242
4241
4240
4237
4250
4251
4249
4248
4247
4246
4245
4243
4242
4240
4239
741 280 743 744 745 747 750749 751000m.E.
742 743 745 746 747 748 749741000m.E. 750 510000 FEET
620000FEET
Founta inCreek
CO
LUM
BIA
SY
NC
LINE
WATE
RLO
O-C
OLU
MB
IA FA
ULT
VALMEYER
AN
TICLIN
E
WAT
ER
LOO
-DU
PO
AN
TIC
LINE
G
G
G
G
G
H
H
H
H
H
G
G
H
H
GH
G
G
G
G
G
G
G
G
G
H
H
H
H
H
H
H
H
H
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
JNJN
JNJN
JNJN
JNJN
JN
JNJN
JNJN
JNJN
JNJN
JNJN
JNJN
JN
500
500
500
500
500
500
550
550
550
550
550
600
600
600600
450
450
400
650
650
700
600
600
650
400
600
600
600
650
600
600
600
650
500500
600
500 600
600
600
650
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e"e
"e
"e
"e "e
"e
"e
"e
"e
"e
"e"e
"e
"e "e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"ee
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e "e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e "e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e"e
"e"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e
"e
"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e"e
"e"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e
"e548
502470
555
510
550
540
555
587
554
512
515
475
455
525510
410
460
396445
470429
658
666
596
628
430
509
583
593582
629
595
621
508
594
552
613
596
562
670
614
603
555
563
505
540
533
467
565552
614 631
636
673
697
628
613
620
619
616
610
655
587
645
661
665
635
600
615
575
635
558
558
527
545
536
505
543
550
621
502
598
542
513
591
602
616
617
489
592
613
467 486
589
569
475
558
511
617633
492
590
718
640
610
530
432
574
595
716
610
581
617
620
524
380
415
622
583
595
666
515
545
587
548
581
593
607
605
600
528
548
707
612 630
627
639
616
600
622
712
583
572
588
604
445
490
533
483
456424
583
657
590
570
610
396
526
536525
611
640
632627
584
520
483
562
672671
589
650
650
545
683
629
522
585
645
588
485
500
566
509 430
604
474
580
598
533
568
621
621
625
723
621
626
601
569
602
560
510
630
647
497595
655
479
652
571
634
605
630
613
548
545
582
589
433
639
574
537
578
475
564635
570
525
545
543
500
591
473
612
599
686
647
480
612
542
635
570500
659
580
653
517
580
670
550
483
658
590
590
525
592
617
585
475
697
630
460
545
623
574
468
663
463
535
605
610
614
659
550
600
583
620
614
611
613
605
647
673
600
590
535
596
581
522
485
654
623
634
575
694
545
590
464
575
430
525
489
493
641
572
618
549
572
630
615
531
477
658
595
618
568
610
624
632
641
588593
576
590
562
583
635
607
545
460
583
536
607
656
607
613 616
560
643
486
594
596
615
570
477