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Robert A. Pettijohn

Publications and source records attributed to Robert A. Pettijohn.

15 recordsLinked to original sources
USGS1993

Properties and chemical constituents in ground water from the middle Claiborne Aquifer, Gulf Coast regional aquifer systems, south-central United States

The U.S. Geological Survey used four programs in 1990 to provide external data quality assurance for the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Results of the intersite- comparison program indicate that 80 and 74 percent of the site operators met the NADP/NTN goals for pH determination and 98 and 95 percent of the site operators met the NADP/NTN goals for specific- conductance determination during the two studies in 1990. The effects of routine sample handling, processing, and shipping determined in the blind-audit program indicated significant positive bias for calcium, magnesium, sodium, potassium, chloride, nitrate, and sulfate. Significant negative bias was determined for hydrogen ion and specific conductance. A Kruskal-Wallis test indicated that there were no significant (a=0.01) differences in analytical results from the three laboratories participating in the interlaboratory-comparison program. Results from the collocated-sampler study indicate the median relative error for potassium and ammonium concentration and deposition exceeded 15 percent at most sites while the median relative error for sulfate and nitrate at all sites was less than 6 percent for concentration and was less than 15 percent for deposition.

Water-Resources Investigations Report↗
USGS1993

Properties and chemical constituents in ground water from the middle Wilcox aquifer, Gulf Coast regional aquifer systems, south-central United States

The Gulf Coast Regional Aquifer-System Analysis is a study of regional aquifers composed of sediments of mostly Cenozoic age that underlie about 230,000 sq mi of the Gulf Coastal Plain. These regional aquifers are part of three aquifer systems: (1) the Mississippi Embayment Aquifer System, (2) the Texas Coastal Uplands Aquifer System, and (3) the Coastal Lowlands Aquifer System. The water chemistry of the Middle Wilcox Aquifer, which is part of the Mississippi Embayment Aquifer System and the Texas Coastal Uplands Aquifer System is presented by a series of maps. These maps show the area1 distribution of (1) the concentration of dissolved solids and temperature, (2) the primary water types and pH, (3) the concentration of major ions and silica, and (4) the milliequivalent ratios of selected ions. Dissolved constituents, pH, temperature, and ratios are based on the median values of all samples in each 100-sq-mi area. The concentration of dissolved solids in water from the Middle Wilcox Aquifer ranges from 26 mg/L in the northern part of the Mississippi Embayment Aquifer System to 125,500 mg/L in a down-dip area in southeastern Texas. The primary water types, which are based on the most frequently observed type in each 100-sq-mi area, are calcium bicarbonate in the outcrop in Missouri, Kentucky, Mississippi, and southern Texas; sodium bicarbonate in the remaining outcrop areas and all areas from outcrop to mid-dip; and sodium chloride in all down-dip areas. The concentrations of major ions in water from the Middle Wilcox Aquifer generally increase from the outcrop area to the down-dip limit of the data. The milliequivalent ratio of magnesium plus calcium to bicarbonate ranges from less than 0.01 to 158 and generally decreases from outcrop to mid-dip and increases from mid-dip to the down-dip limit of the data. From the Sabine Uplift eastward to southwestern Alabama the ratio of bicarbonate to chloride generally decreases from outcrop to down-dip in the area west of the Mississippi River and shows localized trends east of the Mississippi River.

Alabama, Arkansas, Kentucky, Louisiana, Mississipp↗
USGS1993

Properties and chemical constituents in ground water from the lower Wilcox Aquifer, Mississippi Embayment Aquifer System, south-central United States

The Gulf Coast Regional Aquifer-System Analysis is a study of regional aquifers composed of sediments of mostly Cenozoic age that underlie about 230,000 sq mi of the Gulf Coastal Plain. These regional aquifers are part of three aquifer systems: (1) the Mississippi Embayment Aquifer System, (2) the Texas Coastal Uplands Aquifer System, and (3) the Coastal Lowlands Aquifer System. The water chemistry of the Lower Wilcox Aquifer, which is part of the Mississippi Embayment Aquifer System is presented by a series of maps. These maps show the areal distribution of (1) the concentration of dissolved solids and temperature, (2) the primary water types and pH, (3) the concentration of major ions and silica, and (4) the milliequivalent ratios of selected ions. Dissolved constituents, pH, temperature, and ratios are based on the median values of all samples in each 100-sq-mi area. The concentration of dissolved solids in water from the Lower Wilcox Aquifer ranges from 18 mg/L near the outcrop in western Tennessee to 122,000 mg/L in a down-dip area in southern Mississippi. The primary water type is calcium bicarbonate in the outcrop area and sodium bicarbonate in all other areas of the aquifer within the limits of available data. The concentrations of major ions generally increase from the outcrop area to the down-dip limit of the data in the southern part of the aquifer area east of the Mississippi River. The milliequivalent ratio maps of selected ions in water from the Lower Wilcox Aquifer indicate some trends. The milliequivalent ratio of magnesium plus calcium to bicarbonate ranges from less than 0.1 to 40.4 and generally decreases from outcrop to down-dip limit of the data in the southern part of the aquifer area east of the Mississippi River. The milliequivalent ratio of bicarbonate to chloride ranges from 0.01 in southern Mississippi to 52.3 in northwestern Mississippi. This ratio increases from the outcrop toward the Mississippi River and from north to south in the northern part of the aquifer area east of the Mississippi River whereas the ratio increases from outcrop to mid-dip and decreases from mid-dip to down-dip limit of the data in the southern part east of the Mississippi River.

Water-Resources Investigations Report↗
USGS1988

Distribution of dissolved-solids concentrations and temperature in ground water of the Gulf Coast aquifer systems, south-central United States

The distribution of dissolved-solids concentrations and temperature in waters of 10 of the aquifers comprising the gulf coast aquifer systems of the Gulf Mexico Coastal Plain are mapped at a scale of 1:3,500,000. Dissolved solids concentration in the aquifers of the Tertiary System ranges from less than 500 mg/L at the outcrop and subcrop areas to as much as 150,000 mg/L at the downdip extent of these aquifers. A distinct band of sharply increasing concentration of dissolved-solids occurs at about middip of each aquifer of the Tertiary System. Dissolved-solids concentration in younger aquifers ranges from less than 500 mg/L in outcrop and subcrop areas to about 70,000 mg/L at the downdip extent of these aquifers. Temperature of waters in permeable Tertiary deposits ranges from about 18 C at the outcrop and subcrop areas to 90 C at the downdip extent of these aquifers. Temperature of waters in younger deposits ranges from about 14 C at the outcrop and subcrop areas to 30 C at their downdip extent.

Gulf Coast aquifer systems↗
USGS1984

Generalized potentiometric-surface map of the High Plains aquifer in Wyoming, 1981

A potentiometric-surface map shows the general configuration of the water surface for the High Plains Aquifer, which is composed of Oligocene age and younger rocks in southeastern Wyoming. The potentiometric contours are shown at 100-foot intervals on a map at a scale of 1:250,000. The High Plains Aquifer in Wyoming underlies an area of 8,190 square miles and geologically consists of the White River Formation of Oligocene age, the Arikaree Formation of early Miocene age, the Ogallala Formation of late Miocene age, and alluvial deposits of Quaternary age. The altitude of the potentiometric surface declines from about 7 ,100 feet in southwestern Laramie County to about 4,100 feet in eastern Goshen County. Typically, the slope is between 20 and 30 feet per mile; the general direction of flow is eastward. (USGS)

Water-Resources Investigations Report↗
USGS1983

Hydraulic conductivity, specific yield, and pumpage — High Plains aquifer system, Nebraska

Hydrologic data used to evalute the ground-water potential of the High Plains aquifer system in Nebraska are presented on maps showing the hydraulic conductivity and specific yield of the aquifer system and the volume and distribution of water pumped for irrigation from the aquifer system during 1980. The High Plains aquifer system underlies 177,000 square miles in parts of eight states, including 64,770 square miles in Nebraska. It consists of the Ogallala Formation and Tertiary and Quaternary deposits that are saturated and hydraulically connected to the Ogallala. The hydraulic conductivity of the aquifer system varies from greater than 200 feet per day in parts of the North Platte, Platte, Elkhorn, and Republican River valleys to less than 25 feet per day in the northwestern part of the state. Specific yield of the aquifer system ranges from 10 to 20 percent in most of the state and averages 16 percent. The estimated volume of water recoverable from the aquifer system in Nebraska is 2,237 million acre-feet. Inches of water withdrawn from the aquifer system during 1980 varied from less than 1.5 in the sandhills of north-central Nebraska to more than 12 in the Platte River and Blue River basins. This withdrawal represents about 6,703,000 acre-feet of ground water.

Nebraska↗