Geology topics

G.N. Ryals

Publications and source records attributed to G.N. Ryals.

7 recordsLinked to original sources

USGS1988

Evaluation of available data on the geohydrology, soil chemistry, and ground-water chemistry of Gas Works Park and surrounding region, Seattle, Washington

Gas Works Park, in Seattle, Washington, is located at the site of an abandon gasification plant on Lake Union. Wastes deposited during 50 years of plant operations (1906-1956) have extended the shore line 100 ft and left the park soil contaminated with a number of hazardous material. Soil contaminants include polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls, pesticides, volatile organic compounds, cyanide, and metals. PAHs and metals have been detected in Lake Union sediments. Maximum total PAH concentrations exceeded 100 million micrograms/kilogram in some places in the soils of the park at 6-inch depths and in some lake sediments. Other contaminants present are much lower in concentrations. The park is on glacial drift overlain by gasification waste materials and clean fill. Waste materials include sand and gravels, mixed with lampblack, oil, bricks, and other industrial wastes. Groundwater flows through the soils and waste toward Lake Union. Vertical groundwater movement is uncertain, but is assumed to be upward near Lake Union. Concentrations of most soil contaminants are probably low in the groundwater and in Lake Union due to the low solubilities and high sorptive characteristics of these contaminants. However, no water quality data are available to confirm this premise. (USGS)

Water-Resources Investigations Report↗

USGS1984

Regional geohydrology of the northern Louisiana salt-dome basin, part II, geohydrologic maps of the Tertiary aquifers and related confining layers

Regional geohydrologic maps show the altitude of the base and the thickness of the aquifers of Tertiary age and related confining layers in the northern Louisiana salt-dome basin. The limit of freshwater in aquifers is also shown. The basin has an area of about 3,000 square miles, and four geologic units of Tertiary age contain regional aquifers. From oldest (deepest) to youngest, the aquifers are in the Wilcox Group, Carrizo Sand, Sparta Sand, and Cockfield Formation. As the Wilcox is hydraulically interconnected with the overlying Carrizo, they are treated as one hydrologic unit, the Wilcox-Carrizo aquifer. The aquifers are separated by confining layers that retard water movement. In the northwestern part of the area, the Wilcox-Carrizo aquifer is separated from the underlying sand facies of the Nacatoch Sand (Cretaceous age) by a confining layer composed of the Midway Group (Tertiary age) and the underlying Arkadelphia Marl and an upper clay and marl facies of the Nacatoch Sand (both of Cretaceous age). In the remainder of the area, the Wilcox-Carrizo aquifer is separated from an underlying Cretaceous aquifer comprised of the Tokio Formation and Brownstown Marl by the Midway Group and several underlying Cretaceous units which in order of increasing age are the Arkadelphia Maril, Nacatoch Sand, Saratoga Chalk, Marlbrook Marl , and Annona Chalk. The Wilcox-Carrizo aquifer is separated from the Sparta aquifer by the overyling Cane River Formation. The Sparta aquifer is separated from the Cockfield aquifer by the overlying Cook Mountain Formation.

Louisiana↗

USGS1983

Regional geohydrology of the northern Louisiana salt-dome basin, part IV, hydraulic characteristics of the Wilcox-Carrizo aquifer

The Wilcox Group of Paleocene-Eocence age and the Carrizo Sand of Eocene age compose the Wilcox-Carrizo aquifer. Results of 25 aquifer tests and permeability determinations from 43 sidewall cores show that the hydraulic characteristics of the aquifer are variable. Studies of the Carrizo showed that hydraulic conductivity increased as sand-bed thickness increased. Hydraulic conductivity averaged 29 feet per day for sand beds 25 to 100 feet in thickness and 40 feet per day for sand beds 100 to 200 feet in thickness. Based on the aquifer tests and sidewall core analyses, hydraulic conductivity does not increase with increased thickness for the Wilcox part of the aquifer. Permeabilities determined from sidewall cores ranged from less than 1 to more than 3,000 millidarcies (less than 0.002 to more than 7.3 feet per day). Values of hydraulic conductivity determined from aquifer tests ranged from less than 1 to 35 feet per day. (USGS)

Louisiana↗

USGS1982

Regional geohydrology of the northern Louisiana salt-dome basin; Part I, conceptual model and data needs

As part of the National Waste Terminal Storage Program, the U.S. Geological Survey is conducting a regional study of the geohydrology of the northern Louisiana salt-dome basin and developing a regional multi-layered ground-water flow model to determine regional flow paths. In the salt-dome basin the Tokio Formation and Brownstown Marl (Austin aquifer in this report), and Nacatoch Sand of Late Cretaceous age and the Wilcox Group, Carrizo Sand, Sparta Sand, and Cockfield Formation of Tertiary age contain regional aquifers within the maximum potential repository depth of 3,000 feet. The Cretaceous units contain saltwater throughout the basin. The Tertiary units contain freshwater to varying distances downdip from outcrop areas in the basin. Natural flow directions and rates of movement of groundwater have been changed in the salt-dome basin by the withdrawl of freshwater and by the injection of wastes (principally oil-field brines) into saline aquifers. Except for the Sparta aquifer, ground-water flow directions are not well known because of a lack of potentiometric data. A regional test-drilling program, to collect the data needed to document concepts of the flow system and to quantify inputs to the planned ground-water flow model, has been proposed. The Sparta aquifer is being modeled because data are available for the unit. As regional test drilling provides data on other units, will be added to the model developed for the Sparta aquifer. (USGS)

Open-File Report↗

USGS1981

Potentiometric surface of the Wilcox-Carrizo aquifer; Bienville, Red River, and northern Natchitoches, and southern Webster Parishes, Louisiana

The potentiometric surface of the Wilcox-Carrizo aquifer in central northwestern Louisiana is shown by contours using data collected from 1960 to 1980. The aquifer is not affected by regional water-level declines as no large pumping centers have been developed. Seasonal water-level fluctuations in wells are generally less than 10 feet annually.

Louisiana↗

USGS1980

Potentiometric surface maps of the Sparta Sand, northern Louisiana and southern Arkansas, 1900, 1965, 1975, and 1980

The potentiometric surface of the Sparta Sand in northern Louisiana is shown by contours on four maps. Maps for 1900, 1965 , and spring 1975 are generalized, small-scale maps from previously published reports. The spring 1980 map (1:500,000) is based on measurements in 144 wells and includes the southern tier of counties in southern Arkansas. The map shows regional effects of pumping from the Sparta Sand and effects of local pumping centers at Magnolia and El Dorado, Ark., and at Minden, Ruston, Jonesboro-Hodge, Winnfield, Bastrop, and in the Monroe area of Louisiana.

Arkansas, Louisiana↗

USGS1980

Selected hydrologic data from the vicinity of Rayburns and Vacherie salt domes, northern Louisiana salt-dome basin

The U.S. Department of Energy is considering salt domes in northern Louisiana as possible sites for storage of nuclear waste from commercial sources. As part of this National Waste Terminal Storage (NWTS) Program, the U.S. Geological Survey is conducting a regional study of the geohydrology of the northern Louisiana salt-dome basin. Field studies involving the collection of data began in 1977. Data-collection networks were established for both ground- and surface-water sources in the vicinity of two salt domes, Rayburns and Vacherie. Ground-water data collection involved measuring water levels and sampling existing production wells and test wells drilled by the Louisiana State University Institute for Environmental Studies. Samples were analyzed for one or more of the following categories of chemical constituents: inorganic, trace metal, and radiochemical. A network of surface-water stations was set up for measuring discharge and collecting periodic samples. Initial sampling was for analysis for inorganic chemical constituents and radioactive elements. Subsequent sampling has been to determine inorganic chemical constituents.

Louisiana↗