Geological Survey Division GLOSSARY.......................................................................2 Report of Investigation 13 ABSTRACT .......................................................................3 GENERAL INFORMATION...............................................3 GEOLOGY FOR ENVIRONMENTAL PLANNING IN Geology..........................................................................3 MONROE COUNTY, MICHIGAN Topography ....................................................................3 by Andrew J. Mozola Water Supply..................................................................4 Sewerage .......................................................................4 Prepared in cooperation with the Department of Geology BEDROCK GEOLOGY .....................................................4 Wayne State University Relation to Michigan Basin.............................................4 Detroit, Michigan 1970 Stratigraphy....................................................................4 Geologic Map .................................................................5 PREFACE Topography of Bedrock Surface ....................................6 This report summarizes the surface and subsurface Limitations of the Bedrock Topography Map.......................6 geology of Monroe County. The series of maps Economic Resources .....................................................7 accompanying the report are based upon an extensive collection of well records and test boring data. Although Summary.............................................................................8 the sources of these records are too numerous to GLACIAL GEOLOGY........................................................8 acknowledge individually, each contribution is gratefully appreciated. Principal contributors to this project include Nature of Deposits .........................................................8 Mr. Olen Marshall (water well contractor), Mr. James E. Drift Thickness Map .......................................................9 Akers of the Monroe County Health Department, the state Geological Survey Division, and the Michigan Department Summary...........................................................................10 of State Highways. GROUND-WATER RESOURCES...................................10 The author is indebted to Mrs. Patricia L. Mozola for Porosity and Permeability ............................................10 transcribing the many well and test boring records, and for field assistance in pinpointing their exact locations on Water Table..................................................................11 base maps. In all mapping projects, much tedious labor is Occurrence in Drift .......................................................11 involved plotting, checking, and revising to achieve a satisfactory final product. These tasks were diligently Water-Table (or Unconfined) Aquifers...............................11 performed by Messrs. Dan W. Walchak and Jon E. Artesian (or Confined) Aquifers .........................................12 Salsburg, undergraduate students in the Department of Geology. Finally, the author is extremely grateful to Mr. Occurrence in Bedrock.................................................15 Robert W. Kelley of the Michigan Geological Survey for Circulation .........................................................................15 editing both maps and manuscript for publication. Piezometric Levels ............................................................16 To a significant degree, this project was supported by funds provided by the United States Department of the Piezometric Map ...............................................................17 Interior as authorized under the Water Research Act of Potential Sources of Contamination.............................18 1964, Public Law 88-379. Septic Tanks .....................................................................19 Andrew J. Mozola Professor of geology Infiltration From Surface....................................................20 Department of Geology Fertilizers and Pesticides ..................................................21 Wayne State University Quarries and Sinkholes.....................................................21 May 1970 Mineral and Disposal Wells...............................................21 Detroit, Michigan 48202 Drainage Wells..................................................................21 Artesian Spring Failures....................................................21 CONTENTS SUMMARY ......................................................................21 PREFACE..........................................................................1 REFERENCES CITED ....................................................22 CONTENTS .......................................................................1 REFERENCES FOR PLANNERS...................................22 ILLUSTRATIONS ..............................................................2 APPENDIX.......................................................................23 Report of Investigation 13 – Page 1 of 26 Antrim Shale (Late Devonian)......................................23 single hydrologic system. ........ Error! Bookmark not defined. Traverse Group (Middle Devonian)..............................23 Figure 15. Despite the overlying till, wells in bedrock are not necessarily secure from contamination by septic tanks. Dundee Formation (Middle Devonian) .........................24 ................................................ Error! Bookmark not defined. Detroit River Group (Middle Devonian)........................24 Figure 16. Sand bodies often serve as conduits for transmitting both potable and contaminated water to bedrock aquifers. Bois Blanc Formation (Middle Devonian).....................25 ................................................ Error! Bookmark not defined. Bass Islands Group (Late Silurian) ..............................26 Figure 17. The lithology of glacial drift may change with depth. Salina Group (Late Silurian).........................................26 ................................................ Error! Bookmark not defined. Tables ILLUSTRATIONS Table 1. Coliform counts in streams (Mpn/100 ml) ..................18 Table 2. Results of 240 partial ground-water analyses in Monroe Figures Co. ....................................................................................19 Figure 1. Topographic uplands and lowlands influenced the deployment of ice lobes along the glacier front. ...........Error! Bookmark not defined. GLOSSARY Figure 2. Glacial features of southern Michigan, northwest Ohio, Alluvium -- Clastic sediments resulting from stream and northeast Indiana (after Geological Society of America, deposition. 1959). ......................................Error! Bookmark not defined. Aquifer -- Water bearing formation. Figure 3. In general, the water-table surface is a subdued reflection of the overlying land surface (after U.S. Basement complex -- Rock series of complex composition Geological Survey, Primer on Water)....Error! Bookmark not and structure beneath a sedimentary sequence. Usually defined. Precambrian, but occasionally younger. Figure 4. The water levels of lakes and wells respond to Calcareous -- Containing calcium carbonate (CaCO3). fluctuations of the water-table surface...Error! Bookmark not defined. Carbonate -- A salt or ester of carbonic acid; compound Figure 5. In a theoretic model of an isotropic aquifer, ground containing the radical CO3. water moves in the direction of diminishing head. Dashed Clastic -- Textural term applied to rocks composed of lines connect points of equal head. .......Error! Bookmark not fragmental materials usually derived by weathering from defined. pre-existing rocks. Figure 6. The cone of depression resulting when a water-table well is pumped may affect nearby wells, lakes, and streams. Contact -- Place, or surface, where two different kinds of ................................................Error! Bookmark not defined. rocks are adjacent to each other. Figure 7. This hypothetic water-table contour map shows how Dip -- Angle at which a stratum or any planar feature local ground-water movement may vary considerably from departs from the horizontal. Dip is perpendicular to the the regional movement............Error! Bookmark not defined. strike. Figure 8. Perched (false) water tables are not uncommon in Drift -- Term applied to all materials of glacial origin, glacial deposits........................Error! Bookmark not defined. whether deposited directly from the ice or in melt water. Figure 9. Changes in glacial drift lithology often result in Evaporite -- Salts deposited as the result of complete confined conditions of ground-water movement...........Error! evaporation of the solvent. Natural salts are usually Bookmark not defined. impure due to the inclusion of other non-soluble Figure 10. Diagrammatic cross section showing five different sediments. confined aquifers and their corresponding piezometric levels. ......................................Error! Bookmark not defined. Exposure -- That portion of a rock unit exposed to view. Figure 11. Distribution of sandy and gravelly surface features in Glaciofluvial -- Pertaining to waters flowing from glaciers southeast Michigan. ................Error! Bookmark not defined. or to deposits resulting therefrom. Figure 12. In carbonate rock terrane, ground-water movement Glaciolacustrine -- Pertaining to glacial lake conditions or can be unconfined