Surficial Geology Map for the Freeport East 7.5 Minute Quadrangle

Surficial Geology Map for the
Freeport East 7.5 Minute Quadrangle,
Stephenson County, Illinois
Surficial Geology Map for the Freeport East
7.5 Minute Quadrangle, Stephenson
County, Illinois
2013
87
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89
0
930
Qg
92
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0
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91
93 0
96
92
0
Og
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0
870
Qc
83 0
Qg
Qpr
840
8 90
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Qpr
820
0
0
820
90 0
Qg
89
82
0
900
870
900
88
0
8 5 0 86 0
Qpr
890
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0
810
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890 Qg
80
0
0
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860
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0
Qg
Qg
780
840
830
85
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780
760
760
0
760
Qpr
750
780
0
780
840
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0
Qpr
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860
0
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840
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830
830
800
0
0
0
850
Qh
770
84
81
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85
80
85
0
Railroads
Roads
k
0
81
8 30
83
0
800
820
820
83
8 20
Qh
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790
840
Qh
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Water
820
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Dolomitic limestone with chert
nodules. Partially weathered at
surface with evidence of karstic
features.
Og
820
830
Qh
780
0
Qh
0
Qh
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790
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ek
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83
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C
790
8 40
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820
790
0
Ogp
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8 20
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8 10
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10
Galena Platteville Dolomite
840
830
80 0
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Dolomitic silty, clayey, shale.
Lenses of dolomitic limestone are
interbedded throughout.
Qg
82
0
Qpr
790
Qg
8 10
Qh
83 0
0
81
84 0
790
750
780
750
760
e ek
760
760
780
760
0
82
810
800
790
Qh
20
0
Yell
81
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82
81
0
Og
0
Og
Cr a
820
0
50
80
Qh
75
7 80
Qh
0
0
0
79
800
Qh
US
76
81
780 77
0
7
Qh
78
0
Qh
c atonica R
790
0
US Bus 20 800
Qh
Maquoketa Shale
0
0
78
7 70
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Qh
77
81
Qc
840
Og
790
810
Pe
770
0
ive
86
REFERENCES
76
770
7 80
r
0
ive
810
830
850
0
Diamicton (till). Reddish-brown sandy clay
loam with distinct clay films on ped faces. 510% gravel.
77
aR
77 0
76
on
ic
Qc
860
80
Glasford Formation
Winnebago
Formation
Ordovician System
740
760
Qpr 800
840
840
770
Silt (loess) with some thin lenses of sandy
loam. Commonly associated with ground
moraines. Occurs as an eolian deposit in
uplands, colluvium along slopes, and reworked
alluvium within stream and river valleys.
790 7 Qg
70
Qg
Qc
7 60
780
84 0
0
0
ec
760 P
at
80
81 0
760
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Qh
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79
760
760
810
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ree
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iv e
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P e c a t on
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84
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800
7
60
0
760
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780
0
80
830
820
80 0
82
760
Og
840
Peoria Roxanna
Roxana Silt
Silts
Qpr
Qpr
86
830
Organic silt and clay. Intertongues with
Cahokia Formation.
Stratified sands and gravels of moderate to
considerable thickness. A glaciofluvial deposit
that is channelized along stream and river
valleys during glacial retreat.
Qh
890
860
IL 75
0
89
780
Grayslake Peat
Qg
8 70
0
84
Qg
900
88
Og
Qc
Henry Formation
0
Og
Modern creek valley and river channel
deposit that is primarily composed of stratified
silt, clay, and sand.
Qgp
Qg
0
0
81
880
830
Qpr
Qpr
Floodplain
Alluvium
Cahokia Alluvium
930
Qpr
88
89
Qg
810
Qpr
Qg
Floodplain
Alluvium
Qpr
800
0
10
88
10
9
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0
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86
91
0
9 2 9 30
88Qg
0
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0
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0
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92
92
930
9 10
0
940
950
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0
0
Og
930
Og
83
94
Og
950
96 0
Quaternary System
Qg
9 40
Qg
Qpr
Qc
0
890
Qpr
92
940
Qg
Qg
920
95
0
0
90
920
950
950
Qg
930
940
Qg
Qpr
Berg, R. C., Kempton, J. P., Follmer, L. R., and McKenna, D. P., 1985, Illinoian and Wisconsinan stratigraphy and environments in northern Illinois: the Altonian revised, Champaign, IL,
Illinois State Geological Survey Guidebook 19, Midwest Friends of the Pleistocene, 32nd Field Conference, 177 p.
Cote, W., Reinertsen, D., Killey, M., 1970, Guide Leaflet: Geological Science Field Trip - Freeport area; Stephenson County (Freeport, Lena, and Pecatonica Quadrangles), Champaign,
IL, Illinois State Geological Survey Guide Leaflet 1970 C.
Doyle, F. L., 1965. Geology of the Freeport Quadrangle, Illinois, Illinois State Geological Survey Circular 365.
Frohling, D.K, Malone, D.H., and Shields, W.E. 2007, Geologic Map of the Ransom Quadrangle, LaSalle County, Illinois, Scale 1:24,000. Illinois State Geological Survey EDMAP Series
#19.Frye, J. C., Glass, H. D., Kempton, J. P., and Willman, H. B., 1969, Glacial tills of northwestern Illinois, Survey, I. S. G., Champaign, IL, Circular 437, 47 p.
Illinois Environmental Protection Agency, 2009, Source Water Assessment Program Fact Sheet: Freeport, Illinois Environmental Protection Agency.
Illinois State Geological Survey, 2009, Physiographic Divisions of Illinois, Volume 2011.
Kolata, D. R., Buschback, T. C., and Treworgy, J. D., 1978, The Sandwich Fault of Northern, IL, Champaign, IL, Illinois State Geological Survey Circular 505, 26 p.
Kolata, D. R., and Graese, A. M., 1983, Lithostratigraphy and Depostional Environments of the Maquoketa Group (Ordovician) in Northern Illinois: , Champaign, IL, Illinois State
Geological Survey Circular 528, 49 p.
Leighton, M.M. and J.A. Brophy, 1961, Illinoisian Glaciation in Illinois, The Journal of Geology, vol.69, no. 1, 31p.
McGarry, C. S., 2000, Bedrock geology map, Jo Daviess County, Illinois: Illinois State Geological Survey, scale 1:62,500.
Stiff, B., 2000, Surficial Deposits of Illinois: Illinois State Geological Survey.
Visocky, A., Sherrill, M., and Cartwright, K., 1985, Geology, Hydrology, and Water Quality of the Cambrian and Ordovician Systems in Northern Illinois, Cooperative Groundwater Report
10.
Walls, T.A. and Malone D.H., 2005, Geologic Map of the Marseilles, IL 7.5 Minute Quadrangle, Scale 1:24,000. Illinois State Geological Survey EDMAP Series #3.
Weibel, C. P., and Panno, S. V., 1997, Karst terrains and carbonate bedrock of Illinois: Illinois State Geological Survey, 1:500,000 Scale.
Williams, S., and Booth, C., 2002, Modeling and Delineation of the Five-Year Recharge Area for the Freeport CWS Facility 1770200, Stephenson County, Illinois: A Report to the Illinois
Environmental Protection Agency under Contract Agreement #WLS-8303.County, Illinois.
Willman, H. B., and Frye, J. C., 1969, High-level glacial outwash in the Driftless Area of northwestern Illinois, Survey, I. S. G., Champaign, IL, Circular 440, 21 p.
-, 1970, Pleistocene Stratigraphy of Illinois, Champaign, IL, 204 p.
Willman, H. B., Glass, H. D., and Frye, J. C., 1989, Glaciation and origin of the geest in the driftless area of northwestern Illinois, Survey, I. S. G., Champaign, Ill, Circular 535, 44 p.
Willman, H. B., and Kolata, D. R., 1978, The Platteville and Galena Groups in Northern Illinois, Champaing, IL, Illinois State Geological Survey Circular 502, 75 p.
Og
Qg
0
840
940
Qg
Not much is known of the large-scale geology of Stephenson County. Though numerous wells
have been drilled within the Freeport East Quadrangle, the geologic data provided from these wells
have not been collected, organized, and analyzed. The principal focus of this project will be to
create a surficial geologic map of the Quaternary and overlying units within the region. The
surficial geology map is needed to understand the local geology and will assist in future geologic
and hydrogeologic investigations within the Freeport area. Due to the composition of the partially
buried bedrock valley and the current downcutting of the Pecatonica into the surrounding geology
there is a need to assess both shallow and deep aquifer sensitivity within the region. There is also
potential for aggregate resource development as there are currently eighteen small quarries within
the region.
The Freeport East 7.5’ Quadrangle, 1:24,000 scale, is located in the northwestern corner of Illinois
within Stephenson County. Stephenson County is bounded to the north by the Wisconsin border, to
the east by Winnebago County, and to the west by Jo Daviess County. The quadrangle is located in
the area between 89°37’30W and 89°30’W longitude and 42°22’30N and 42°15’N latitude. The
Freeport East Quadrangle includes the eastern portion of Freeport, Illinois, which serves as the
largest municipality in the county with a population of 24,161 individuals. The drainages in the
quadrangle include the Pecatonica River, Crane Grove Creek, Silver Creek, Winneshiek Creek, and
Yellow Creek. The area can be accessed by US 20, Illinois Route 75, and Illinois Route 26 and
dozens of country roads and city streets.
Much of the glacial deposits in the Freeport East Quadrangle were deposited during the late
Pleistocene (Doyle, 1965). Nearly all the valleys within the area were filled with glacial drift as the
glacier advanced from the east on a S75°W trend. Stream diversion channels, thinness of drift
throughout the area, the absence of end-moraines, and the presence of kames and eskers are all
evidence that once the glacier stagnated over the Freeport East quadrangle and melted from the top
down. (Doyle, 1965). The glacial deposits that cover the area are generally referred to as the
Glasford Formation. The drift is predominantly composed of glacial till, outwash sands and
gravels, and silts.
In the Freeport area there is approximately 2400ft of Paleozoic material that rest on a Precambrian
basement (Cote et al., 1970). The bedrock geology of the area is dominated by Ordovician strata of
the Ancell, Galena, Platteville, and Maquoketa Groups (Kolata et al., 1978; Kolata and Graese,
1983; McGarry, 2000). The Ancell Group consists of the St. Peter and Glenwood Formations. The
Galena and Platteville Groups are collectively more than 100 m (320 ft) in thickness and consist of
layers of dolostone. The dolostone ranges from coarsely fossiliferous to micritic, and is locally
cherty and/or heavily bioturbated. Thin layers of bentonite also are present.
The major surface drainage feature within the Freeport region is the Pecatonica River. The
Pecatonica River flows eastward along the northern border of Freeport, cutting through the
northeastern portion of town. The river is approximately 30 m wide with a gradient of
approximately 0.13 m per km (Williams and Booth, 2002). The watershed associated with the
Pecatonica River covers a total of 2,000 km2 in Winnebago, Stephenson, Jo Daviess, and Carroll
counties (Illinois Environmental Protection Agency, 2009). The watershed consists of a total 655
km of stream (Illinois Environmental Protection Agency, 2009).
Data used to create this map were compiled from Illinois State Geological Survey water borehole
records, field observations, seismic refraction analysis, and the United States Department of
Agriculture soil survey maps. Electronic files were gathered from multiple state and federal agency
websites to determine elevation contours, roads, railroads, and water channels.
89
Qg
9 40
Qpr
900
Cheyenne Morgan, Eric Peterson, Robert Nelson,
Kathryn Schroeder, Dave Malone
Department of Geology-Geography, Illinois State University
2013
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830
MjrHwys
Elevation Contour