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D. G. Woodward

Publications and source records attributed to D. G. Woodward.

11 recordsLinked to original sources
USGS1998

Hydrogeologic framework of the Willamette Lowland aquifer system, Oregon and Washington

This report summarizes the hydraulic characteristics of the materials that make up the Willamette Lowland aquifer system, ground-water movement in the aquifer system, estimates of ground-water recharge, ground-water quality characteristics, construction and use of cross-sectional numerical ground-water flow models, hydrologic controls on ground-water movement, water budgets and flow paths, and a description and application of a conceptual model.

Professional Paper↗
USGS1997

Seismic investigation of the buried horst between the Jornada del Muerto and Mesilla ground-water basins near Las Cruces, Dona Ana County, New Mexico

Six seismic reflection profiles were collected in the vicinity of the Jornada Horst between Goat Mountain and Tortugas Mountain (northeast and east of Las Cruces, New Mexico) to delineate more precisely the geometry of the horst and to determine whether large, buried channels have been incised into the top of the horst. The Jornada fault zone separates the southern Jornada del Muerto ground-water basin from the Mesilla ground-water basin in the Mesilla drainage basin. The upper part of the Jornada Horst is composed of Tertiary volcanic and volcaniclastic rocks; these rocks overlie Permian sedimentary rocks. The horst, in turn, is overlain by unconsolidated sediments of the upper Santa Fe Group. Some test holes indicate that little or no ground water flows from the Jornada del Muerto ground-water basin to the Mesilla ground-water basin over some portions of the horst. However, some ground water flows through the upper Santa Fe Group deposits above some portions of the horst. Ground-water flow immediately east of the horst near U.S. Highway 70 is deflected northward in the southern Jornada del Muerto ground-water basin presumably because of the change from higher hydraulic-conductivity values of aquifer materials in the southern basin to lower hydraulic-conductivity values of materials in the horst. Incised, buried channels, if present on the horst, could be filled with alluvial material with higher hydraulic- conductivity values than those of the material in the horst. Incised, buried channels would allow ground water to readily move from the Jornada del Muerto ground-water basin to the Mesilla ground-water basin. The gross geometry of the horst--eastern extent, constraints on the western extent, and general altitude of the top--was discerned by interpretations of the seismic profiles. The presence or absence of large channels incised into the top of the horst could not be confirmed by these interpretations. However, the seismic interpretations suggest that the water table is above the top of the horst for most of its extent between U.S. Highway 70 and Tortugas Mountain and that the top of the horst is above the water table and acts as a subsurface flow barrier north of U.S. Highway 70.

Water-Resources Investigations Report↗
USGS1995

Occurrence and quality of ground water in southwestern King County, Washington

The 250-square mile study area in southwestern King County, Washington is underlain by sediments as much as 2,200 feet thick, deposited during at least four continental glacial/interglacial periods. Published surficial geologic maps and drillers' lithologic logs from about 700 field-located wells were used to prepare 28 geologic sections; these sections were used to delineate 9 hydrogeologic units--5 aquifers, 3 confining beds, and a basal, undifferentiated unit. Two aquifers in these sediments occur at the land surface. Maps depicting the configuration of the tops of three buried aquifers show the extent and the geometry of those aquifers. Maps showing the thickness of two of the three buried aquifers also were prepared. Potentiometric-surface maps for the major aquifers are based on water levels measured in about 400 wells during April 1987. Hydraulic characteristics of the major aquifers are mapped using more than 1,100 specific-capacity calculations and about 240 hydraulic-conductivity determinations from selected wells. Estimates of the average annual recharge to the ground-water system from precipitation for the entire study area were based on relations determined from modeling selected basins. Discharges from the ground-water system were based on estimates of springflow and diffuse seepage from the bluffs surrounding the uplands, and on the quantity of water withdrawn from high-capacity wells. A total of 242 water samples was collected from 217 wells during two mass samplings and analyzed for the presence of common constituents. Samples also were collected and analyzed for heavy metals, boron, detergents, and volatile organic compounds. These analyses indicated there was no widespread degradation of ground-water quality in southwestern King County.

Water-Resources Investigations Report↗
USGS1986

Hydrogeologic framework and properties of regional aquifers in the Hollandale Embayment, southeastern Minnesota

In 1977, the U.S. Geological Survey began a series of investigations of regional aquifer systems in the United States. These studies will provide quantitative information for use in developing and managing regional ground-water supplies. One of these studies, the Northern Midwest Regional Aquifer-System Analysis (RASA) project, concerns the Cambrian and Ordovician age aquifers that occur in southeastern Minnesota and in parts of five other states: Illinois, Indiana, Iowa, Missouri, and Wisconsin (Steinhilber and Young, 1979). This report describes the hydrogeologic framework and properties of the regional aquifers in the Hollandale embayment in southeastern Minnesota (fig. 1). Two other reports describing different aspects of the regional aquifers in southeastern Minnesota were also prepared. Delin and Woodward (1984) mapped the potentiometric surface of each regional aquifer, and described the regional flow regimes; and Woodward (1985) presented a summary of 100 years of water use in southeastern Minnesota based upon trends in municipal-well installations and aquifer utilization.

Minnesota↗
USGS1986

Hydrogeologic and water-quality characteristics of the Cretaceous aquifer, southwestern Minnesota

The Cretaceous aquifer in southwest Minnesota consists of discontinuous, basal sandstone beds in the Dakota Formation and the overlying Codell Sandstone Member of the Carlile Shale of the Colorado Group. These sandstone beds are not laterally or vertically persistent throughout the area and generally are separated shale beds in the Dakota Formation and in the overlying Colorado Group of Cretaceous age. Water in the Cretaceous aquifer is confined by overlying shale and by overlying till as much as 700 feet thick. Locally where the drift is permeable and thin and where the shale is missing, water in the aquifer is unconfined. Groundwater moves away from the Sioux Quartzite Ridge north toward the Minnesota River, south toward Iowa, and eastward toward the Mississippi River. Recharge to the aquifer primarily is by infiltration of precipitation that percolates through the overlying drift and underflow in the aquifer from South Dakota. Water in the Cretaceous aquifer consists of five chemical types based on predominant ions; including calcium-magnesium bicarbonate, calcium-magnesium sulfate, sodium chloride, sodium bicarbonate, and sodium sulfate type waters. Dissolved-solids, chloride, and sulfate concentrations in the aquifer locally exceed standards recommended by the U.S. Environmental Protection Agency for public supplies, particularly in areas southwest of the Minnesota River.

Minnesota↗
USGS1985

Trends in municipal-well installations and aquifer utilization in southeastern Minnesota, 1880-1980

Water distributed by municipal systems has been the largest off-stream use of water in southeastern Minnesota for the past 100 years. Water pumped by these systems in 1980 totaled 102.3 billion gallons, with 60.1 billion gallons supplied by ground water. Ground water supplies 294 of the 309 municipal systems in the area. The development of ground-water supplies for municipal use in southeastern Minnesota began around the 1880's as an alternative to supplies from lakes and rivers. After about 4,500 Minnesotans died from typhoid from 1891 to 1900, deep wells became widely used in order to avoid contaminated surface water. An inventory of 1,244 wells drilled for municipal systems from 1880 to 1980 has been completed. Of the five bedrock aquifers in the study area, the Prairie du Chien-Jordan is the most extensively used for water supply; 537 municipal wells tap it. About half of these wells were drilled in the Twin Cities Metropolitan Area since 1945 to accommodate suburban growth. The undifferentiated drift aquifer ranks second in use with 294 municipal wells tapping it. Most of these wells are completed in aquifers buried in thick drift deposits in the western part of the study area. Aquifer preference was analyzed to determine whether municipal wells were completed in the shallowest bedrock aquifer present in an area, in a deeper bedrock aquifer, or in a drift aquifer above the bedrock. Until 1950, there was a strong preference to complete municipal wells in the Upper Carbonate aquifer. Because of poor water quality in parts of the aquifer, most municipal wells drilled in the area since 1950 are cased through the Upper Carbonate and completed in deeper aquifers. The St. Peter aquifer is little used for municipal wells because wells completed in it often pump sand. About 96 percent of the municipal wells drilled in the St. Peter aquifer subcrop area since 1950 were cased through the St. Peter and completed in deeper aquifers. About 64 percent of the municipal wells drilled in the Mount Simon-Hinckley aquifer subcrop area are completed in drift aquifers. The Prairie du Chien-Jordan and Ironton-Galesville aquifers are preferred for municipal wells in their respective areas of occurrence. Water appropriation in Minnesota is regulated through a permit system based on five water-use priorities. Domestic water supply, excluding industrial and commercial uses of a municipal water supply, is the highest priority (Minnesota Statutes, Chapter 105.41). Under the regulations, uses of a lower priority are not permitted to adversely affect uses of a higher priority. Identification of the aquifer(s) used for municipal supplies is also necessary to safeguard these supplies from adverse effects of competing water users and contamination, and to evaluate the consequences of each.

Minnesota↗
USGS1985

Seismic-refraction study of suspected drift-filled bedrock valleys in Ramsey County, Minnesota

Seismic-refraction surveys were made across suspected buried, drift-filled bedrock valleys believed to underlie two sites of known ground-water contamination the Twin Cities Army Ammunition Plant (TCAAP) near New Brighton and the former Koppers Coke Plant in St. Paul, Ramsey County, Minnesota. Refraction data were collected along two lines at each site; each line traversed the axis of a suspected valley. Drift-filled bedrock valleys were thought to incise the Prairie du Chien-Jordan aquifer to an altitude between 500 and 560 feet above sea level at the TCAAP site. The interpretation of one seismic profile indicates that a valley probably does not exist under the area surveyed; the modeled depth profile shows the bedrock surface ranging between altitudes of about 700 to 780 feet. Interpretation of a second seismic profile just south of the TCAAP indicates that a shallow valley may exist under the northern half of the line; the modeled depth profile shows that the bedrock surface declines from an altitude of about 780 feet to about 690 feet over a horizontal distance of 400 feet. A drift-filled bedrock valley was thought to incise the St. Peter aquifer to an altitude between 770 and 800 feet above sea level at the Koppers site. The interpretation of a seismic profile just east of the Koppers site is not conclusive, but suggests that a bedrock valley may be present near the middle of the line. The interpretation of a second seismic profile across the westward extension of the same suspected valley also is not conclusive, but suggests that a bedrock valley may be present at the north end of the line. The optimal field layout for each line at the site (longer shot offsets) could not be obtained because of limited space available in the densely developed residential neighborhoods.

Minnesota↗
USGS1984

The study of buried drift aquifers in Minnesota by seismic geophysical methods

Buried-drift aquifers are stratified sand and (or) gravel aquifers in glacial deposits that cannot be seen or inferred at the land surface. During the Pleistocene Epoch, four continental glaciations advanced and retreated across Minnesota, blanketing the bedrock surface with drift as much as 700 feet thick (fig. 1). Most of the drift consists of till, an unsorted, un-stratified mixture of clay silt, sand, and gravel that usually is not considered to be an aquifer. Permeable, stratified sand and gravel, deposited as outwash, alluvium, and (or) ice-contact deposits usually during an earlier glacial episode and subsequently covered (buried) with till, form the buried-drift aquifers.

Minnesota↗
USGS1984

Hydrogeologic setting and the potentiometric surfaces of regional aquifers in the Hollandale Embayment, southeastern Minnesota, 1970-80

Sedimentary Paleozoic rocks in the Hollandale embayment in southeastern Minnesota are as thick as 2,000 ft. This sedimentary sequence, together with the Proterozoic Hinckley Sandstone and the Quaternary drift, is divided into six regional aquifers: undifferentiated drift, Upper Carbonate, St. Peter, Prairie du Chien-Jordan, Ironton-Galesville, and Mount Simon-Hinckley. Potentiometric-surface maps for each aquifer indicate that movement of ground water is predominantly toward the major rivers. The St. Croix, Minnesota, and Mississippi Rivers constitute regional discharge boundaries for ground-water flow. A major ground-water divide in the St. Peter, Prairie du Chien-Jordan, Ironton-Galesville, and Mount Simon-Hinckley aquifers in the south-central part of the Hollandale embayment separates ground-water flow northward toward the Twin Cities area and southward toward Iowa. The St. Peter and Prairie du Chien-Jordan aquifers in the southeastern part of the embayment contain ground-water mounds as high as 90 ft above the regional potentiometric surface. The mounds occur as a result of increased recharge where the Decorah-Platteville-Glenwood confining bed has been removed by erosion and the aquifers subcrop beneath drift that is about 20 ft thick. This head distribution produces a locally complex pattern of flow in which ground water moves southwesterly toward Iowa instead of directly toward the Mississippi River.

Minnesota↗
USGS1984

Areal lithologic changes in bedrock aquifers in southeastern Minnesota as determined from natural-gamma borehole logs methods

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.

Minnesota↗