Regional Aquifer System Analysis-Michigan Basin
About half of Michigan's population depends on ground water as a source of domestic and public supply. The potential for ground-water development in large
areas of the Lower Peninsula, however, is not well defined. Saline water underlies freshwater aquifers everywhere in the State. Migration of saline water resulting
from pumping or drilling boreholes too near the transition from freshwater to saline water has caused abandonment of wells. The two primary bedrock aquifers,
the Marshall and the Saginaw, are used extensively in the southern part of the State. In the Lansing area, water levels have been drawn down as much as 160 feet
below predevelopment levels. A better understanding of the hydrogeology and the occurrence of fresh and saline water is needed for effective management of the
region's ground-water resources.
(1) Describe the geologic, hydrologic, and water-quality characteristics of a regional aquifer system in the central part of Michigan's Lower Peninsula, (2) delineate
the vertical and areal extent of freshwater and identify areas subject to saline-water encroachment, (3) simulate movement of ground water in the aquifer system
using computer models, and (4) relate ground-water chemistry to rock mineralogy and ground-water movement through use of geochemical models and
laboratory analyses of rock and water chemistry.
(1) Developed a work plan, reviewed literature, and compiled existing data, (2) defined the geologic framework of the aquifer system, (3) delineated the transition
from fresh to saline ground water using water-quality analyses and borehole and surface geophysics, (4) developed a density dependent ground-water-flow model
to simulate regional ground-water movement, (5) collected ground-water samples for laboratory analysis to define regional ground-water chemistry, and (6)
collected rock samples for laboratory analysis to define rock chemistry and mineralogy to define rock-water chemical interactions.
RESULTS LAST YEAR:
The vertical and areal extent of freshwater in the aquifer system was estimated. Freshwater is most abundant in the glaciofluvial aquifer in the northern part of the
Lower Peninsula. Another area of abundant freshwater is present in the Saginaw aquifer in a 20-mile wide corridor that trends north-south from just west of
Saginaw Bay to the Lansing metropolitan area. East and west of this corridor the aquifer thins and water is often too saline for most uses. To the west, where the
Saginaw aquifer underlies Jurassic "red beds," saline water is related to the "red beds." To the east, in the Saginaw Lowlands, saline water is present throughout
the aquifer system in most places.
In general, those areas where bedrock aquifers are poorly connected to the overlying glacial deposits contain saline ground water. Recharge rates to the
glaciofluvial aquifer were estimated from long-term streamflow data. These rates are being used as input to a model to simulate ground-water flow with the
MODFLOW computer program. Major-ion chemistry and isotope data for water from the aquifer system were interpreted to help explain variations in water
quality and its relation to geology and ground-water flow.
PLANS THIS YEAR:
During the final year of the study, nine Water-Resources Investigations reports will be published to document major findings of the study. Four summary reports
will be prepared for publication. Results of the study will also be presented at professional society and agency meetings.
HEADQUARTERS OFFICE: Lansing, Michigan
FIELD LOCATION: Lower Peninsula, Michigan
PROJECT CHIEF: Norman G. Grannemann
PERIOD OF PROJECT: October 1985 to September 1994
Baltusis, M.A., Quigley, M.S., and Mandle, R.J., 1992, Municipal ground- water development and withdrawals in the central Lower Peninsula of Michigan,
1870-1987: U.S. Geological Survey Open-File Report 91-215, 89 p.
Dannemiller, G.T., and Baltusis, M.A., Jr., 1990, Physical and chemical data for ground water in the Michigan Basin, 1986-89: U.S. Geological Survey
Open-File Report 90-368, 164 p.
Fitterman, D.F., 1986, Transient electromagnetic soundings in the Michigan Basin for ground-water evaluation: National Water Well Association Conference on
Surface and Borehole Geophysical Methods and Ground Water Instrumentation, Denver, Colorado, October 15-17, 1986, Proceedings, p. 334-353.
Holman, A.J., Abraczinskas, L.M., and Westjohn, D.B., 1988, Pleistocene Proboscideans and Michigan salt deposits: National Geographic Research, v. 4, no.
1, p. 4-5.
Mandle, R.J., 1986, Plan of study for the regional aquifer system analysis of the Michigan Basin: U.S. Geological Survey Open-File Report 86-494, 23 p.
Mandle, R.J., and Westjohn, D.B., 1987, Preliminary interpretation of vertical electrical-resistivity soundings in the Saginaw Valley, Michigan: U.S. Geological
Survey Open-File Report, 87-474, 45 p.
____1989, Geohydrologic framework and ground-water flow in the Michigan Basin, in Swain, L.A., and Johnson, A.I., eds., Regional Aquifer Systems of the
United States, Aquifers of the Midwestern Area: American Water Resources Association Monograph Series, no. 13, p. 83-110.
Meissner, B.D., Long, D.T., and Lee, R.W., 1994, Selected geochemical characteristics of water from the Saginaw aquifer in the Michigan Basin: U.S.
Geological Survey Water-Resources Investigations Report 93-4220, 19 p.
Swain, L.A., 1986, Michigan Basin regional aquifer-system study, in Sun, R. J., ed., Regional Aquifer-System Analysis Program of the U.S. Geological
Survey--summary of projects, 1978-84: U.S. Geological Survey Circular 1002, p. 242-244.
Wahrer, M.A., Long, D.T., and Lee, R.W., 1994, Selected geochemical characteristics of ground water from the glaciofluvial aquifer in the central Lower
Peninsula of Michigan: U.S. Geological Survey, Water-Resources Investigations Report 94-4017, 21 p.
Westjohn, D.B., 1989, Application of geophysics in the delineation of the freshwater/saline-water interface in the Michigan Basin, in Swain, L.A., and Johnson,
A.I., eds., Regional Aquifer Systems of the United States, Aquifers of the Midwestern Area: American Water Resources Association Monograph Series, no. 13,
____1993, Regional Aquifer-System Analysis double-packer aquifer tests, in Latkovich, V.J., ed., Proceedings of a pressure transducer-packer workshop, June
25-28, 1991: U.S. Geological Survey Open-File Report 93-71, p. 19-20.
Westjohn, D.B., and Carter, P.J., Jr., 1989, Direct-current vertical-electrical resistivity soundings in the Michigan Basin: U.S. Geological Survey Open-File
Report 89-244, 57 p.
Westjohn, D.B., Olsen, H.W., and Willden, A.T., 1990, Matrix-controlled hydraulic properties of Mississippian and Pennsylvanian sandstones from the Michigan
Basin: U.S. Geological Survey Open-File Report 90-104, 42 p.
Westjohn, D.B., Weaver, T.L., and Zacharias, K.F., Hydrogeology of Pleistocene glacial deposits and Jurassic "red beds" in the central Lower Peninsula of
Michigan: U.S. Geological Survey Water-Resources Investigations Report 93-4152, 17 p.
Zacharias, K.F., Sibley, D.F., Westjohn, D.B., and Weaver, T.L., 1993, Oxygen-isotope, X-ray-diffraction, and scanning-electron-microscope examinations of
authigenic-layer-silicate minerals from Mississippian and Pennsylvanian sandstones in the Michigan Basin: U.S. Geological Survey Open-File Report 93-103, 15