Hydrogeologic Cross Sections By John D. Barry
1
Groundwater Atlas of Winona County Hydrogeologic Cross Secons County Atlas Series C-34, Part B Plate 6 of 6 Minnesota Department of Natural Resources Groundwater Atlas Program mndnr.gov/groundwatermapping To accompany atlas Report and Plate 5. G’ 1000 1100 1400 1300 1200 900 800 500 600 700 400 300 200 100 0 1000 1100 1400 1300 1200 900 800 500 600 700 400 300 200 100 0 Elevation (feet) G Opo Os Opo _j Opo Opo Opo _tc lower Opo Opo Opo _m Opg Os _e Ops Opo Opo Opo Opo _w Opo Ops Ops Opg Ops _tc _j _j _j _j _j _j _j _m _w _tc _j _m _w _w _tc Ops _sl _tc lower _e _sl _tc lower _tc lower _tc lower _e _e _sl _sl _sl _sl _sl 9.12 5.52 800 700 1050 800 750 650 850 2500 3000 20,000 4000 CSAH 43 CR-113 USTH 61 MNTH 43 CSAH 33 Pine Creek Hanson Valley Rd Mississippi River Hemmingway Creek Pine Creek Rush Creek Burns Valley Creek MNTH 76 Money Creek Money Creek 3.75 3.63 1.34 F’ 1000 1100 1400 1300 1200 900 800 500 600 700 400 300 200 100 0 1000 1100 1400 1300 1200 900 800 500 600 700 400 300 200 100 0 Elevation (feet) F _sl Opo _w Opg _tc Ops Opo Opo _tc lower _tc lower Opo Ops Opo _j Os _j _sl Oc Opo Od _sl _tc Opo _e _tc lower _sl _e _e Ops _m _m _w _w _tc _tc _j _j _j _j _j _m _j Opg 10.7 13.6 8.96* 16.2 5.98 650 850 900 800 900 700 1050 MNTH 76 CSAH 17 CR-123 Rush Creek Pine Ridge Dr MNTH 43 Pine Creek Money Creek CSAH 1 ISTH 90 Trout Run Creek CSAH 16 Mississippi River CR-111 Ahrensfeld Creek Sinkholes common 1.89 6.22 12.5 1.92 3.53 1.38 E’ 1000 1100 1400 1300 1200 900 800 500 600 700 400 300 200 100 0 1000 1100 1400 1300 1200 900 800 500 600 700 400 300 200 100 0 Elevation (feet) E _e _e _e _tc lower _tc lower _tc lower Ops Ops Opo Ops _w _w _w _j Opo _sl _sl _sl _sl _e _tc lower _sl Od Od Opo Oc Opo _j _j _j _j Ops Opg _tc Os Opg _m _m _m _m _tc _tc _tc _tc _w _j _tc Ops Opo Opo _sl Ops _tc Ops Os Ops Opo _sl _j Mississippi River CSAH 25 Cedar Valley Creek CSAH 9 Rush Creek Rd MNTH 74 Rush Creek CSAH 37 ISTH 90 Little Pickwick Creek USTH 61 CSAH 29 CSAH 15 Pickwick Creek ISTH 90 CSAH 3 CSAH 19 Sinkholes common 16.7 18.6 12.0 23.8 6000 2000 5500 800 700 850 750 1000 650 1100 2.62 11.9 12 1.8 10.4 15.2 1.62 1.09 D’ 1000 1100 1300 1200 900 800 500 600 700 400 300 200 100 0 1000 1100 1300 1200 900 800 500 600 700 400 300 200 100 0 Elevation (feet) D Opo _tc lower _j _j _j _j _j _j _tc _sl _tc lower _tc lower _sl _w _w _w _w Opo _tc lower Ops Os _sl Opo Opo _m _m _m Opo Ops _tc _tc _tc _tc _e _e _e _sl _sl Os Opo CSAH 25 USTH 61 CSAH 23 CSAH 21 Little Pickwick Creek Richmond Creek CSAH 15 E Burns Valley Rd MNTH 74 MNTH 43 CSAH 37 Burns Valley Creek, East Mississippi River CSAH 33 Sinkholes common 8.59 Recent 33.3 30.3 5.51 20.9 46 7.82 13.2 7.96 96.0* 1050 650 1000 800 700 1000 850 750 4.93 11.7 14.0 4.53 4.3 8.4 8.2 3.78 C’ 1000 1100 1300 1200 900 800 500 600 700 400 300 200 100 0 1000 1100 1300 1200 900 800 500 600 700 400 300 200 100 0 Elevation (feet) C _tc _w _w _w _tc lower Opo Ops _sl Ops _m _m Os Ops _tc _tc _j _j _j _j _sl Opo Opo Ops _tc lower Opo _e _e Opo Mississippi River USTH 61 MNTH 74 Cemetery Rd Burns Valley Creek, East CSAH 21 Garvin Brook Whitewater River, South Branch N Broadway St Skyline Dr Rollingstone Creek CSAH 25 Sinkholes common 15.5 20.4 16.1 11.6 13,000 2000 800 900 700 900 800 650 750 900 850 3.64 5.1 11.3 4.64 6.4 1.75 B’ 1000 1100 1300 1200 900 800 500 600 700 400 300 200 100 0 1000 1100 1300 1200 900 800 500 600 700 400 300 200 100 0 Elevation (feet) B Ops _sl _tc lower Opo _j Ops _tc _m _m Ops _sl _j _w _tc _sl _j Opo Opo Opo _e _e CSAH 25 CR-114 Whitewater River CSAH 26 MNTH 248 MNTH 74 USTH 61 Whitewater River, North Branch Mississippi River Rollingstone Creek 28.1 1000 9.7* 43.1 26.9 750 800 650 750 800 700 750 850 4.50 1.20 16.6 3.29 A’ 1000 1100 1300 1200 900 800 500 600 700 400 300 200 100 0 1000 1100 1300 1200 900 800 500 600 700 400 300 200 100 0 Elevation (feet) A _e _tc _tc _sl _sl Ops Ce Opo _tc lower _m Opo Opo _j _j _j _w Ops Fischer Hill Dr CSAH 28 CSAH 25 CSAH 31 Mississippi River USTH 61 MNTH 74 Whitewater River 5.58 8.98 6000 700 850 750 850 2.16 4.73 43° 52' 30" N. 44° N. 91° 22' 30" W. 91° 37' 30" W 44° 07' 30" N. 91° 45' W. 91° 52' 30" W. 92° W. 91° 30' W. Dresbach Dakota Utica Lewiston St. Charles Stockton Goodview Winona Minnesota City Elba Altura Witoka ¦ 90 ¤ 61 ¤ 61 ¤ 14 ¤ 14 ) 74 ) 248 ) 43 ) 43 ) 76 ¦ 90 E’ F’ G’ D’ C’ B’ A’ E F G D C B A Symbols Part B line of cross section Water samples shown on cross section A A’ N 1 0 1 2 3 4 SCALE 1:400 000 1012 4567 KILOMETERS 3 5 MILES Unconsolidated Cummingsville Decorah Shale* Platteville and Glenwood formations* St. Peter Shakopee Oneota Dolomite* Jordan St. Lawrence Formation* Upper Lone Rock Lower Lone Rock Formation* Wonewoc Eau Claire Formation* Mt. Simon Oc Od Opg Os Ops Opo _j _sl _tc _w _e _m _tc lower Bedrock aquifers and aquitards Cross Section Explanation Interpreted tritium age is indicated by pattern color. See Figure 6 in the report for geologic unit correla�on. *aquitard 1 0 1 2 3 4 5 MILES 1 0 1 2 4 5 6 7 8 3 9 KILOMETERS SCALE 1:100 000 VERTICAL EXAGGERATION X 20 Symbols and labels General groundwater flow direction Geologic contact Approximate equipotential contour 800 Tritium age Darker color in small vertical rectangle (well screen symbol) indicates tritium age of water sampled in well. Lighter color indicates interpreted age of water in aquifer. Mixed: water is a mixture of recent and vintage waters (greater than 1 TU to less than 8 TU). Well not sampled for tritium. Vintage: water entered the ground before 1953 (less than or equal to 1 TU). Recent: water entered the ground since about 1953 (8 to 15 tritium units [TU]). Spring (symbol color indicates tritium age of water sample) Chloride: if shown, concentration is ≥5 ppm. (* naturally elevated) 26.9 Nitrate: if shown, concentration is ≥1 ppm. 3.53 Arsenic: if shown, concentration is ≥1 ppb. 1.62 Carbon-14 ( 14 C): if shown, estimated groundwater residence time in years. 6000 Enhanced-permeability zone Direction of fault movement, arrows indicate relative movement For detailed descriptions of the units, see the report “Geology and physical hydrology” section and Figure 6 “Bedrock stratigraphy, hydrostratigraphy, and distribution of karst features.” Northern cross secons: A–Aʹ and B–Bʹ The landscape is deeply dissected by the Whitewater River valley and smaller tributary valleys. The first bedrock units are primarily the Shakopee (Ops) and Oneota (Opo) formations of the Prairie du Chien Group and are prone to karst feature development. The Oneota is not as protective in this area of the county as it is elsewhere, as suggested by Jordan (_j) aquifer samples with mixed tritium and elevated chloride and nitrate. Where deeply buried, the St. Lawrence aquitard (_sl) limits mixing of recent water with older vintage water. Below the St. Lawrence the carbon-14 age of groundwater ranges from 6,000 years on the western side (near the Whitewater River) to 1,000 years in the east (near CSAH 25). Within valleys the St. Lawrence’s protective characteristics are diminished and springs show evidence of groundwater mixing. Local groundwater movement is vertically downward and toward streams and tributaries. Regional groundwater movement is east, where groundwater discharges to the Mississippi River. Central cross secons: C–Cʹ, D–Dʹ, and E–Eʹ The western county landscape is a relatively flat plateau. Deeply dissected valleys progressively increase from the central portions to the east. First bedrock units are primarily the Shakopee and Oneota formations of the Prairie du Chien Group, which are prone to karst feature development. Sinkholes are common in the western and central portions. In the western and central portions of cross sections C–Cʹ and D–Dʹ, the Oneota lacks the characteristics of an aquitard as indicated by mixed tritium and elevated chloride and nitrate in the Jordan aquifer. In the western portions of cross sections E–Eʹ, the Oneota is more deeply buried and has characteristics of an aquitard, indicated by the carbon-14 age of 2,000 years for a Jordan–St. Lawrence well (near ISTH 90). Where deeply buried, the St. Lawrence aquitard limits mixing of recent water with older vintage water. Below the St. Lawrence the carbon-14 age of groundwater ranges from 5,500 (E–Eʹ, near CSAH 19), to 13,000 (C–Cʹ, near Skyline Drive) years. Within valley settings, the St. Lawrence’s protective characteristics are diminished and springs show evidence of groundwater mixing. Local groundwater movement is vertically downward and toward streams and tributaries. Regional groundwater movement is east, where groundwater discharge occurs to the Mississippi River. Southern cross secons: F–Fʹ and G–Gʹ The western portions of cross sections F–Fʹ and G–Gʹ are relatively flat plateaus where the Oneota varies in its hydrologic properties. On cross section F–F’, a Jordan aquifer sample east of CR-111 shows mixed tritium with elevated chloride and nitrate, suggesting the Oneota lacks protective characteristics in the area. However, on cross section G–G’ the unit behaves as an aquitard as indicated by vintage tritium and a carbon-14 age of 2,500 years near Money Creek. The central and eastern portions of these cross sections are deeply dissected by tributaries to the Root River. First bedrock units are primarily the Shakopee and Oneota formations of the Prairie du Chien Group, which are prone to karst feature development. Where deeply buried, the St. Lawrence aquitard limits mixing of recent water with older vintage water. However, in the east its protective characteristics are diminished. Samples from the Lone Rock (_tc) and Wonewoc (_w) aquifers show mixed tritium and elevated chloride nitrate. Springs also show evidence of groundwater mixing. Local groundwater movement is vertically downward and toward streams and tributaries. Regional groundwater movement is east, where groundwater discharges to the Mississippi River. Groundwater from the Mt. Simon aquifer in extreme southeastern Winona County had a carbon-14 age of 20,000 years (G–Gʹ, near USTH 61). LOCATION DIAGRAM This map was compiled and generated in a geographic informaon system. Digital data products are available from the DNR Groundwater Atlas Program. This map was prepared from publicly available informaon. Every reasonable effort has been made to ensure the accuracy of the data on which this map interpretaon is based. However, the DNR does not warrant the accuracy, completeness, or any implied uses of these data. Users may wish to verify crical informaon; sources include both the references in the report and informaon on file in the offices of the Minnesota Geological Survey and the DNR. Every effort has been made to ensure the interpretaon shown conforms to sound geologic and cartographic principles. This map should not be used to establish legal tle, boundaries, or locaons of improvements. Base modified from Minnesota Geological Survey, Geologic Atlas of Winona County, 2014. Universal Transverse Mercator projecon, zone 15N, North American Datum of 1983. North American Vercal Datum of 1988. 500 Lafayee Road St. Paul, MN 55155-4025 888-646-6367 or 651-296-6157 mndnr.gov The Minnesota DNR prohibits discriminaon in its programs and services based on race, color, creed, religion, naonal origin, sex, marital or familial status, disability, public assistance status, age, sexual orientaon, and local human rights commission acvity. Individuals with a disability who need a reasonable accommodaon to access or parcipate in DNR programs and services please contact the DNR ADA Title II Coordinator at [email protected], 651-259-6157 (voice) or call using your preferred Telecommunicaons Relay Provider. Discriminaon inquiries should be sent to Minnesota DNR, 500 Lafayee Road, St. Paul, MN 55155-4049. This informaon is available in alternave format on request. © 2021, State of Minnesota, Department of Natural Resources and the Regents of the University of Minnesota Prepared and published with the support of the Minnesota Environment and Natural Resources Trust Fund and the Clean Water, Land and Legacy Amendment Hydrogeologic Cross Secons By John D. Barry 2021
Transcript of Hydrogeologic Cross Sections By John D. Barry
Groundwater Atlas of Winona CountyHydrogeologic Cross Sections
County Atlas Series C-34, Part BPlate 6 of 6
Minnesota Department of Natural ResourcesGroundwater Atlas Programmndnr.gov/groundwatermapping
To accompany atlas Report and Plate 5.
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91° 52' 30" W.92° W.
91° 30' W.
Dresbach
Dakota
UticaLewiston
St. Charles
Stockton
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Winona
MinnesotaCity
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E’
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Symbols
Part B line of cross section
Water samples shown on cross section
A A’
N
1 0 1 2 3 4
SCALE 1:400 000
1 0 1 2 4 5 6 7 KILOMETERS3
5 MILES
Unconsolidated
Cummingsville
Decorah Shale*
Platteville and Glenwood formations*
St. Peter
Shakopee
Oneota Dolomite*
Jordan
St. Lawrence Formation*
Upper Lone Rock
Lower Lone Rock Formation*
Wonewoc
Eau Claire Formation*
Mt. Simon
Oc
Od
Opg
Os
Ops
Opo
_j
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_tc
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_tc lower
Symbols and labels
General groundwater flow direction
Geologic contact
Approximate equipotential contour800
Tritium age
Darker color in small vertical rectangle (well screen symbol) indicates tritium age of water sampled in well. Lighter color indicates interpreted age of water in aquifer.
Mixed: water is a mixture of recent and vintage waters (greater than 1 TU to less than 8 TU).
Well not sampled for tritium.
Vintage: water entered the ground before 1953 (less than or equal to 1 TU).
Recent: water entered the ground since about 1953 (8 to 15 tritium units [TU]).
Spring (symbol color indicates tritium age of water sample)
Chloride: if shown, concentration is ≥5 ppm.(* naturally elevated)
26.9
Nitrate: if shown, concentration is ≥1 ppm.3.53
Arsenic: if shown, concentration is ≥1 ppb.1.62
Carbon-14 (14C): if shown, estimated groundwater residence time in years.
6000
Bedrock aquifers and aquitards
Cross Section Explanation
Interpreted tritium age is indicated by pattern color.See Figure 6 in the report for geologic unit correla�on.
*aquitard
Enhanced-permeability zone
Direction of fault movement, arrows indicate relative movement
1 0 1 2 3 4 5 MILES
1 0 1 2 4 5 6 7 83 9 KILOMETERS
SCALE 1:100 000VERTICAL EXAGGERATION X 20
Unconsolidated
Cummingsville
Decorah Shale*
Platteville and Glenwood formations*
St. Peter
Shakopee
Oneota Dolomite*
Jordan
St. Lawrence Formation*
Upper Lone Rock
Lower Lone Rock Formation*
Wonewoc
Eau Claire Formation*
Mt. Simon
Oc
Od
Opg
Os
Ops
Opo
_j
_sl
_tc
_w
_e
_m
_tc lower
Symbols and labels
General groundwater flow direction
Geologic contact
Approximate equipotential contour800
Tritium age
Darker color in small vertical rectangle (well screen symbol) indicates tritium age of water sampled in well. Lighter color indicates interpreted age of water in aquifer.
Mixed: water is a mixture of recent and vintage waters (greater than 1 TU to less than 8 TU).
Well not sampled for tritium.
Vintage: water entered the ground before 1953 (less than or equal to 1 TU).
Recent: water entered the ground since about 1953 (8 to 15 tritium units [TU]).
Spring (symbol color indicates tritium age of water sample)
Chloride: if shown, concentration is ≥5 ppm.(* naturally elevated)
26.9
Nitrate: if shown, concentration is ≥1 ppm.3.53
Arsenic: if shown, concentration is ≥1 ppb.1.62
Carbon-14 (14C): if shown, estimated groundwater residence time in years.
6000
Bedrock aquifers and aquitards
Cross Section Explanation
Interpreted tritium age is indicated by pattern color.See Figure 6 in the report for geologic unit correla�on.
*aquitard
Enhanced-permeability zone
Direction of fault movement, arrows indicate relative movement
For detailed descriptions of the units, see the report “Geology and physical hydrology” section and Figure 6 “Bedrock stratigraphy, hydrostratigraphy, and distribution of karst features.”
Northern cross sections: A–Aʹ and B–Bʹ The landscape is deeply dissected by the Whitewater River valley and smaller tributary valleys. The first bedrock units are primarily the Shakopee (Ops)and Oneota (Opo) formations of the Prairie du Chien Group and are prone to karst feature development. The Oneota is not as protective in this area of the county as it is elsewhere, as suggested by Jordan (_j) aquifer samples with mixed tritium and elevated chloride and nitrate. Where deeply buried, the St. Lawrence aquitard (_sl) limits mixing of recent water with older vintage water. Below the St. Lawrence the carbon-14 age of groundwater ranges from 6,000 years on the western side (near the Whitewater River) to 1,000 years in the east (near CSAH 25). Within valleys the St. Lawrence’s protective characteristics are diminished and springs show evidence of groundwater mixing. Local groundwater movement is vertically downward and toward streams and tributaries. Regional groundwater movement is east, where groundwater discharges to the Mississippi River.
Central cross sections: C–Cʹ, D–Dʹ, and E–EʹThe western county landscape is a relatively flat plateau. Deeply dissected valleys progressively increase from the central portions to the east. First bedrock units are primarily the Shakopee and Oneota formations of the Prairie du Chien Group, which are prone to karst feature development. Sinkholes are common in the western and central portions. In the western and central portions of cross sections C–Cʹ and D–Dʹ, the Oneota lacks the characteristics of an aquitard as indicated by mixed tritium and elevated chloride and nitrate in the Jordan aquifer. In the western portions of cross sections E–Eʹ, the Oneota is more deeply buried and has characteristics of an aquitard, indicated by the carbon-14 age of 2,000 years for a Jordan–St. Lawrence well (near ISTH 90). Where deeply buried, the St. Lawrence aquitard limits mixing of recent water with older vintage water. Below the St. Lawrence the carbon-14 age of groundwater ranges from 5,500 (E–Eʹ, near CSAH 19), to 13,000 (C–Cʹ, near Skyline Drive) years. Within valley settings, the St. Lawrence’s protective characteristics are diminished and springs show evidence of groundwater mixing. Local groundwater movement is vertically downward and toward streams and tributaries. Regional groundwater movement is east, where groundwater discharge occurs to the Mississippi River.
Southern cross sections: F–Fʹ and G–GʹThe western portions of cross sections F–Fʹ and G–Gʹ are relatively flat plateaus where the Oneota varies in its hydrologic properties. On cross section F–F’, a Jordan aquifer sample east of CR-111 shows mixed tritium with elevated chloride and nitrate, suggesting the Oneota lacks protective characteristics in the area. However, on cross section G–G’ the unit behaves as an aquitard as indicated by vintage tritium and a carbon-14 age of 2,500 years near Money Creek. The central and eastern portions of these cross sections are deeply dissected by tributaries to the Root River. First bedrock units are primarily the Shakopee and Oneota formations of the Prairie du Chien Group, which are prone to karst feature development. Where deeply buried, the St. Lawrence aquitard limits mixing of recent water with older vintage water. However, in the east its protective characteristics are diminished. Samples from the Lone Rock (_tc) and Wonewoc (_w) aquifers show mixed tritium and elevated chloride nitrate. Springs also show evidence of groundwater mixing. Local groundwater movement is vertically downward and toward streams and tributaries. Regional groundwater movement is east, where groundwater discharges to the Mississippi River. Groundwater from the Mt. Simon aquifer in extreme southeastern Winona County had a carbon-14 age of 20,000 years (G–Gʹ, near USTH 61).
LOCATION DIAGRAM
This map was compiled and generated in a geographic information system. Digital data products are available from the DNR Groundwater Atlas Program.
This map was prepared from publicly available information. Every reasonable effort has been made to ensure the accuracy of the data on which this map interpretation is based. However, the DNR does not warrant the accuracy, completeness, or any implied uses of these data. Users may wish to verify critical information; sources include both the references in the report and information on file in the offices of the Minnesota Geological Survey and the DNR. Every effort has been made to ensure the interpretation shown conforms to sound geologic and cartographic principles. This map should not be used to establish legal title, boundaries, or locations of improvements.
Base modified from Minnesota Geological Survey, Geologic Atlas of Winona County, 2014.
Universal Transverse Mercator projection, zone 15N, North American Datum of 1983. North American Vertical Datum of 1988.
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Hydrogeologic Cross Sections
By John D. Barry2021
