Geohydrology and hydrochemistry of aquifers in Cretaceous rocks, Minnesota
No abstract available.
Geology topics
Source-linked reports with geographic coverage including Minnesota.
No abstract available.
Sedimentary rocks of Paleozoic age in the Hollandale embayment in southeastern Minnesota are as much as 2,000 feet thick and, with the underlying Hinckley sandstone of Proterozoic age, comprise the following five layered aquifers (beginning with the oldest): the Mount Simon-Hinckley, Ironton-Galesville, Prairie du Chien-Jordan, St. Peter and Upper Carbonate. Many of the Paleozoic formations show transitional facies changes from a deep marine depositional environment in the middle of the embayment to a near shore environment along the periphery. Borehole natural-gamma logs were collected to investigate the effects of regional lithologic changes on the hydrology of the Ironton-Galesville, Prairie du Chien-Jordan and St. Peter aquifers. Interpretation of natural-gamma logs shows that a fine-grained sandstone at the base of the Galesville sandstone (basal part of the Ironton-Galesville aquifer) thickens toward the central part of the embayment, which may account for the decrease in hydraulic conductivity of the Ironton-Galesville aquifer in that direction. The Jordan sandstone, which underlies the Prairie du Chien Group, consists of three members in southeastern Minnesota: the basal Norwalk member, a silty, fine-grained sandstone; the middle Van Oser member, a coarse- to medium-grained quartzose sandstone; and the upper Sunset Point member, a clayey dolomitic sandstone. The Norwalk and Van Oser members were identified by interpretation of natural-gamma logs. Hydraulic conductivity of the Prairie du Chien-Jordan aquifer generally is highest in the Twin City basin (50 feet per day) where the Van Oser is the predominant member; it is lowest to the east and southeast (25 feet per day) where the Norwalk member thickens. Interpretation of natural-gamma logs indicates that the shaley and silty sandstones that comprise the basal St. Peter confining bed, which separates the St. Peter and Prairie du Chien aquifers, are as much as 80 feet thick in the Twin City basin, but are absent in the southern part of the embayment. Differences in potentiometric head across the basal St. Peter are about 30 feet in the Twin City basin where the confining bed is present but only 5 to 10 feet to the south where the confining bed is absent and where the St. Peter aquifer directly overlies the Prairie du Chien-Jordan aquifer.
No abstract available.
No abstract available.
Streamflow and suspended-sediment-transport data were collected in Garvin Brook watershed in Winona County, southeastern Minnesota, during 1982. The data collection was part of a study to determine the effectiveness of agricultural best-management practices designed to improve rural water quality. The study is part of a Rural Clean Water Program demonstration project undertaken by the U.S. Department of Agriculture. Continuous streamflow data were collected at three gaging stations during March through September 1982. Suspended-sediment samples were collected at two of the gaging stations. Samples were collected manually at weekly intervals. During periods of rapidly changing stage, samples were collected at 30-minute to 12-hour intervals by stage-activated automatic samplers. The samples were analyzed for suspendedsediment concentration and particle-size distribution. Particlesize distributions were also determined for one set of bedmaterial samples collected at each sediment-sampling site. The streamflow and suspended-sediment-concentration data were used to compute records of mean-daily flow, mean-daily suspended-sediment concentration, and daily suspended-sediment discharge. The daily records are documented and results of analyses for particle-size distribution and of vertical sampling in the stream cross sections are given.
A study of runoff to selected lakes was done in the Twin Cities metropolitan area from July 1981 to December 1982. The purpose of the study was to determine differences in nutrient-loading characteristics for lakes with and without wetlands and settling ponds. The study also quantified nutrient loading to lakes on a storm, seasonal, and annual basis, complementing an inlake water-quality study of these lakes done by the Metropolitan Council. Discharge and water-quality data were collected periodically during 1981 and continuously during 1982 at 22 sites located in seven lake watersheds Bryant Lake, Lake Elmo, Fish Lake, Lake George, Lake Riley, Spring Lake, and Square Lake. Basin characteristics and land use were determined for each watershed. Recording instruments provided continuous discharge records at 14 sites and continuous rainfall records at six sites. Automatic water-quality samplers were used at lake inlets. The automatic samplers collected samples at 1- to 2-hour intervals during storms. Lake-outlet samples were collected manually on a weekly basis during flow. Samples were analyzed for suspended solids and nutrients. Atmospheric-input data were collected at eight sites from September 23 to November 1, 1982. Discharge and water-quality data were used to calculate storm, seasonal, and annual loads of total suspended solids, volatile suspended solids, total phosphorus, dissolved phosphorus, nitrite-plus-nitrate nitrogen, ammonia nitrogen, and ammonia-plus-organic nitrogen. All data collected during the study are documented in tables and graphs that contain (1) watershed characteristics and land use; (2) storm concentrations; (3) storm, seasonal, and annual loads; (4) storm hydrographs; (5) atmospheric-input concentrations and loads; (6) storm, seasonal, and annual precipitation totals; and (7) results of quality-assurance tests.
The principal surficial aquifers in southwest Minnesota consist of outwash and alluvium material deposited in river valleys. The largest and most productive of these aquifers occupy the valleys of the Cottonwood, Des Moines, Redwood, and Rock Rivers and of tributaries to the Big Sioux River. Minor aquifers, adequate only for farm or domestic use, occur in the valleys of tributaries to the major streams. The surficial aquifers range in width from half a mile to 2 miles, in thickness from 0 to 110 feet, and in saturated thickness from 0 to 80 feet. Grain size varies both laterally and vertically. A veneer of fine-grained sediment, as much as 15 feet thick, has been deposited over the outwash by postglacial streams. Availability of water in the surficial aquifers varies greatly within short distances. Probable maximum well yield is as much as 1,000 gallons per minute; however, yields generally range from 10 to 100 gallons per minute. The concentration of dissolved solids in water from the surficial aquifers ranges from about 300 to 960 milligrams per liter. Analyses of 25 samples show that locally the water contains concentrations of iron, sulfate, and nitrate (as nitrogen) that are above the limits recommended by the Minnesota Department of Health for drinking water. Based on these standards, the water is of acceptable chemical quality for most uses, although it is hard. (USGS)
The Mount Simon-Hinckley aquifer in southeast Minnesota consists of a thick sequence of sandstone that generally yields large quantities of good-quality water to wells. The aquifer is most important as a source of water supply in the Twin Cities area, where it supplies approximately 10 percent of the ground water used. It is the uppermost bedrock aquifer and, locally, the principal source of domestic supply where it is present north of the Twin Cities. Yield to wells are generally about 500 gallons per minute but may be as high as 2,000 gallons per minute. The aquifer is a good potential source of water because of (1) large quantities of water in storage, (2) adequate yields to wells, and (3) good water quality. The quality of water in the aquifer is generally acceptable for municipal, industrial, and domestic uses. The dissolved-solids concentration in water from the aquifer ranges from a minimum of 48 milligrams per liter to a maximum of 2,810 milligrams per liter. The lowest values are in the eastern and northern parts of the aquifer, where bedrock is at or close to land surface. The highest concentrations are in the southwestern part of the aquifer, where leakage from over lying Cretaceous rocks is highly mineralized water. Magnesium and sulfate concentrations are also high in the southwest. The dissolved-solids concentration generally increases with depth in the aquifer. The predominant water type in the aquifer is calcium magnesium bicarbonate, although sodium chloride waters are present at depth and in the discharge areas along large rivers. This report is one of a series of the hydrogeology and water quality of the 14 principal aquifers in Minnesota prepared by the U.S. Geological Survey. The U.S. Environmental Protection Agency requested these studies because of the need for information to develop its Underground Injection Control Program.
Quality of water in the Prairie du Chien-Jordan aquifer is generally good, except for some localized contamination, Coal-tar derivatives that contaminate the aquifer in St. Louis Park, a western suburb in the Twin Cities Metropolitan Area, pose the most serious threat to water quality. High hardness and iron concentration limit suitability for municipal and industrial use in parts of extreme southeast Minnesota. Confining beds of bedrock and drift, however, protect most of the aquifer from surface pollutants. The Prairie du Chien-Jordan aquifer is part of a sequence of sedimentary bedrock units in southeast Minnesota. The Jordan Sandstone is a white to yellow, fine- to coarse-grained sandstone. The Prairie du Chien Group comprises two dolomitic formations that are vuggy and fractured and interbedded with thin layers of shale. The aquifer formations were deposited in Paleozoic seas that occupied the Hollandale embayment. The aquifer dips toward the interior of the embayment where it is as deep as 750 feet below land surface and as thick as 500 feet. Permeability is secondary in the Prairie du Chien Group because of solution cavities and fractures, and intergranular in the Jordan Sandstone. Water in the aquifer is confined except in the eastern part. Water generally flows to the north and east into the Minnesota and Mississippi Rivers. A ground-water divide separates part of the flow southward into Iowa. This aquifer supplies more water than any other bedrock one in the State. Calcium magnesium bicarbonate type water is most common in the aquifer. Calcium and sulfate and, to a lesser degree sodium and magnesium, increase in concentration toward the southwestern part of the study area. Bicarbonate concentration, on the other hand, decreases toward the southwestern corner of the study area. Leakage from overlying Cretaceous deposits is the source of much of the sulfate and other minerals in the southwest. This report is one of a series on the hydrogeology and water quality of the 14 principal aquifers in Minnesota prepared by the U. S. Geological Survey. The U. S. Environmental Protection Agency requested these studies because of the need for information to develop its Underground Injection Control Program.
Quality of water in the St. Peter aquifer is generally acceptable for most uses. Sulfate concentrations increase toward the southwestern part of the aquifer because of highly mineralized leakage from overlying Cretaceous deposits. Concentrations of sodium, magnesium, and sulfate generally increase to the west, and those of calcium, bicarbonate, and chloride generally increase toward the margins of the aquifer. Calcium magnesium bicarbonate water is the most common type in the aquifer. The aquifer is well protected from surface sources of Contaminants by the overlying Decorah-Platteville-Glenwood confining bed, which overlies about 80 percent of the St. Peter aquifer. Thin drift, which overlies the east side of the aquifer, provides much less protection than the confining bed. Water in the aquifer generally flows toward the Mississippi River and its tributaries. Some water flows southward into Iowa from a ground-water divide in Dodge and Steele Counties, Well yields from the aquifer, which are generally between 100 and 250 gallons per minute, are generally adequate for most uses. This report is one of a series on the hydrogeology and water quality of the 14 principal aquifers in Minnesota prepared by the U.S. Geological Survey. The U. S. Environmental Protection Agency requested these studies because of the need for information to develop its Underground Injection Control Program.
The Upper Carbonate aquifer is part of a sequence of sedimentary bedrock units deposited in Paleozoic seas that occupied a depression known as the Hollandale embayment. The aquifer is comprised of four formations, which, in ascending order, are the Galena Dolomite, Dubuque Formation, Maquoketa Shale, and Cedar Valley Limestone. Total thickness of the aquifer is as much as 650 feet. Yields from wells in the aquifer range from about 100 to 500 gallons per minute. Water flows mostly through fractures and solution channels toward the periphery of the aquifer and, locally, toward river and bedrock valleys. The quality of water in the Upper Carbonate aquifer is suitable for most uses. However, the water is susceptible to contamination in karst areas because sinkholes and disappearing streams provide direct passageways for entry of contaminants into the aquifer. Calcium magnesium bicarbonate type waters are most common. Concentrations of dissolved solids and some major ions, specifically magnesium, sodium, bicarbonate, and sulfate, are generally highest in the southwestern part of the study area.
At least two caribou ( Rangifer tarandus ) were observed in Cook Co. of northeastern Minnesota from October 1980 through April 1981. This is the first record of caribou in the area since 1924. The nearest records of this species were 224 km NE of the present sightings, and the closest known established population of caribou is 240 km away.
Gray wolves ( Canis lupus ) were studied from April-1972 through April 1974 in the Superior National Forest in northeastern Minnesota by radio-tracking and simulated howling. Based on replies during 217 of 456 howling sessions, the following recommendations were derived for using simulated howling as a census technique: (1) the best times of day are dusk and night; (2) July, August, and September are the best months; (3) precipitation and winds greater than 12 km/hour should be avoided; (4) a sequence of 5 single howls should be used, alternating 'flat' and 'breaking' howls; (5) trials should be repeated 3 times at about 2-minute intervals with the first trial at lower volume; and (6) the trial series should be repeated on 3 nights as close to each other as possible. Two censuses are described: a saturation census and a sampling census.
The Pelican River sand-plain area includes approximately 200 square miles of outwash deposits in parts of Decker, Otter Tail, and Clay Counties in west-central Minnesota. Saturated thickness of the outwash is as much as 140 feet and yields of properly constructed wells locally may exceed 1,200 gallons per minute. Recharge to the outwash from snowmelt and rain ranged from 3.2 to 6.1 inches during 1979-80. Discharge from the aquifer, as base flow of the Pelican River, averaged 2.0 inches during 1979-80. Evapotranspiration is 22.4 inches per year. The chemical quality of ground water is suitable for irrigation, as measured by sodium-adsorption ratios, but locally high concentrations of calcium, magnesium, and bicarbonate may cause clogging of well screens. Mathematical models of parts of the ground-water-flow system indicate that lake levels and streamflow may decline because of pumping wells. The exact water-level decline depends on the total number of wells, pumping rates, location of pumping wells with respect to one another and to surface-water bodies, duration of pumping, and the quantity of ground-water recharge. Sensitivity analyses of the models indicates that additional data on hydraulic conductivity, evapotranspiration, and recharge may increase the reliability of model results. Buried aquifers are known to be present in the area. Aquifer-test results showed that pumping from a buried aquifer had no effect on water levels in the unconfined aquifer.
An investigation of flood flows from small drainage basins in Minnesota is being made to aid in the design of bridges, culverts and other highway drainage structures. Results of the investigation provide peak-flow data on streams generally with drainage areas less than 200 square miles, placing particular emphasis on those with drainage areas lees than 10 square miles. Basin parameters being investigated for their effect on floods are drainage area, length of main stream, slope of main channel, basin altitude, forest cover, and storage area. All of the 187 gaging stations included in the report are equipped with crest-stage gages. In addition, 4 stations are equipped to record stage and precipitation continuously. The relative magnitude of flood flows for different hydrologic regions is shown in graphs that relate maximum discharge to drainage area. Station records contain location, drainage area, records available, type of gage, on-site structure elevations, bankfull stage, and annual maximum stage and discharge data. These data, with annual peak data from continuous-record stations, form the basis for statewide flood-frequency studies.