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Anne F Choquette - One of the best experts on this subject based on the ideXlab platform.
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Aqueous Geochemistry of the Sand‐and‐Gravel Aquifer, Northwest Florida
Ground Water, 1991Co-Authors: Brian G Katz, Anne F ChoquetteAbstract:The aqueous geochemistry of the Sand-and-Gravel aquifer in northwest Florida was characterized as part of the Florida Ground-Water Quality Monitoring Network Program, a multiagency cooperative study delineating baseline and/or background water quality for the major aquifer systems throughout the State. The aquifer is the principal source of water in northwest Florida and consists predominantly of quartz Sand with smaller amounts of andesine, chlorite, calcite, kaolinite, and illite. Water from 42 wells in the Sand-and-Gravel aquifer sampled during 1986 and 1987 was characteristically low in dissolved solids (median value of 72 milligrams per liter) and of nondistinct water type, although relative concentrations of magnesium and sulfate tended to be lower than those of other major ions. Nonparametric statistical tests of major-ion concentration variations with depth and relative distance along flow paths indicate that the water chemistry does not change significantly (0.05 significance level) as the water moves vertically and laterally through the aquifer. Mass-balance calculations indicate that dissolved solids from rainfall and saline-water sources each account for 13 percent of the concentration of dissolved solids in ground water. Incongruent dissolution of andesine, chlorite, and muscovite to form kaolinite accounts for 94 percent of the neutralization of the total hydrogen ion input from rainfall and from carbonic acid weathering in the subsurface. The remaining neutralization is accounted for by the dissolution of calcite.
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aqueous geochemistry of the Sand and Gravel aquifer northwest florida
Ground Water, 1991Co-Authors: Brian G Katz, Anne F ChoquetteAbstract:The aqueous geochemistry of the Sand-and-Gravel aquifer in northwest Florida was characterized as part of the Florida Ground-Water Quality Monitoring Network Program, a multiagency cooperative study delineating baseline and/or background water quality for the major aquifer systems throughout the State. The aquifer is the principal source of water in northwest Florida and consists predominantly of quartz Sand with smaller amounts of andesine, chlorite, calcite, kaolinite, and illite. Water from 42 wells in the Sand-and-Gravel aquifer sampled during 1986 and 1987 was characteristically low in dissolved solids (median value of 72 milligrams per liter) and of nondistinct water type, although relative concentrations of magnesium and sulfate tended to be lower than those of other major ions. Nonparametric statistical tests of major-ion concentration variations with depth and relative distance along flow paths indicate that the water chemistry does not change significantly (0.05 significance level) as the water moves vertically and laterally through the aquifer. Mass-balance calculations indicate that dissolved solids from rainfall and saline-water sources each account for 13 percent of the concentration of dissolved solids in ground water. Incongruent dissolution of andesine, chlorite, and muscovite to form kaolinite accounts for 94 percent of the neutralization of the total hydrogen ion input from rainfall and from carbonic acid weathering in the subsurface. The remaining neutralization is accounted for by the dissolution of calcite.
Brian G Katz - One of the best experts on this subject based on the ideXlab platform.
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Aqueous Geochemistry of the Sand‐and‐Gravel Aquifer, Northwest Florida
Ground Water, 1991Co-Authors: Brian G Katz, Anne F ChoquetteAbstract:The aqueous geochemistry of the Sand-and-Gravel aquifer in northwest Florida was characterized as part of the Florida Ground-Water Quality Monitoring Network Program, a multiagency cooperative study delineating baseline and/or background water quality for the major aquifer systems throughout the State. The aquifer is the principal source of water in northwest Florida and consists predominantly of quartz Sand with smaller amounts of andesine, chlorite, calcite, kaolinite, and illite. Water from 42 wells in the Sand-and-Gravel aquifer sampled during 1986 and 1987 was characteristically low in dissolved solids (median value of 72 milligrams per liter) and of nondistinct water type, although relative concentrations of magnesium and sulfate tended to be lower than those of other major ions. Nonparametric statistical tests of major-ion concentration variations with depth and relative distance along flow paths indicate that the water chemistry does not change significantly (0.05 significance level) as the water moves vertically and laterally through the aquifer. Mass-balance calculations indicate that dissolved solids from rainfall and saline-water sources each account for 13 percent of the concentration of dissolved solids in ground water. Incongruent dissolution of andesine, chlorite, and muscovite to form kaolinite accounts for 94 percent of the neutralization of the total hydrogen ion input from rainfall and from carbonic acid weathering in the subsurface. The remaining neutralization is accounted for by the dissolution of calcite.
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aqueous geochemistry of the Sand and Gravel aquifer northwest florida
Ground Water, 1991Co-Authors: Brian G Katz, Anne F ChoquetteAbstract:The aqueous geochemistry of the Sand-and-Gravel aquifer in northwest Florida was characterized as part of the Florida Ground-Water Quality Monitoring Network Program, a multiagency cooperative study delineating baseline and/or background water quality for the major aquifer systems throughout the State. The aquifer is the principal source of water in northwest Florida and consists predominantly of quartz Sand with smaller amounts of andesine, chlorite, calcite, kaolinite, and illite. Water from 42 wells in the Sand-and-Gravel aquifer sampled during 1986 and 1987 was characteristically low in dissolved solids (median value of 72 milligrams per liter) and of nondistinct water type, although relative concentrations of magnesium and sulfate tended to be lower than those of other major ions. Nonparametric statistical tests of major-ion concentration variations with depth and relative distance along flow paths indicate that the water chemistry does not change significantly (0.05 significance level) as the water moves vertically and laterally through the aquifer. Mass-balance calculations indicate that dissolved solids from rainfall and saline-water sources each account for 13 percent of the concentration of dissolved solids in ground water. Incongruent dissolution of andesine, chlorite, and muscovite to form kaolinite accounts for 94 percent of the neutralization of the total hydrogen ion input from rainfall and from carbonic acid weathering in the subsurface. The remaining neutralization is accounted for by the dissolution of calcite.
Brian K. Fowler - One of the best experts on this subject based on the ideXlab platform.
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Estimated Sand and Gravel Resources of the South Merrimack, Hillsborough County, New Hampshire, 7.5-Minute Quadrangle
Natural Resources Research, 2006Co-Authors: David M. Sutphin, Lawrence J. Drew, Brian K. FowlerAbstract:A computer methodology is presented that allows natural aggregate producers, local governmental, and nongovernmental planners to define specific locations that may have Sand and Gravel deposits meeting user-specified minimum size, thickness, and geographic and geologic criteria, in areas where the surficial geology has been mapped. As an example, the surficial geologic map of the South Merrimack quadrangle was digitized and several digital geographic information system databases were downloaded from the internet and used to estimate the Sand and Gravel resources in the quadrangle. More than 41 percent of the South Merrimack quadrangle has been mapped as having Sand and (or) Gravel deposited by glacial meltwaters. These glaciofluvial areas are estimated to contain a total of 10 million m^3 of material mapped as Gravel, 60 million m^3 of material mapped as mixed Sand and Gravel, and another 50 million m^3 of material mapped as Sand with minor silt. The mean thickness of these areas is about 1.95 meters. Twenty tracts were selected, each having individual areas of more than about 14 acres (5.67 hectares) of stratified glacial-meltwater Sand and Gravel deposits, at least 10-feet (3.0 m) of material above the watertable, and not sterilized by the proximity of buildings, roads, streams and other bodies of water, or railroads. The 20 tracts are estimated to contain between about 4 and 10 million short tons (st) of Gravel and 20 and 30 million st of Sand. The five most Gravel-rich tracts contain about 71 to 82 percent of the Gravel resources in all 20 tracts and about 54–56 percent of the Sand. Using this methodology, and the above criteria, a group of four tracts, divided by narrow areas sterilized by a small stream and secondary roads, may have the highest potential in the quadrangle for Sand and Gravel resources.
Jan Wierchowiec - One of the best experts on this subject based on the ideXlab platform.
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Tailings from Sand and Gravel processing plants as the potential source of gold
Gospodarka Surowcami Mineralnymi-mineral Resources Management, 2008Co-Authors: Jan WierchowiecAbstract:Tailings produced during the manufacture of aggregates in the Rakowice Sand and Gravel plant (Middle Bobr River valley, SW Poland) were characterized in the paper. A 3.0 inches laboratory Knelson concentrator was used to evaluate the recovery of free gold from tailings collected from the Sand and Gravel processing plant. Gravity recoverable gold (GRG) was determined using the difference between the gold content in the Knelson feed and the tails. Analysis of several samples collected from different types of tailings revealed the average content of 0.27 ppm of gold and recoveries of gold between 85–98% in the concentrates. The Sand and Gravel deposits are thus potential sources of gold and other economic heavy minerals, mainly of ilmenite and titanomagnetite, as well as small amounts of zircon, monazite and rutile. The annual deposition of about 6 kg of Au and 1000 Mg of other heavy minerals in the tailing pond during the last 5 years of the Rakowice Mine operation has been assessed. 147
B Sutton - One of the best experts on this subject based on the ideXlab platform.
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Sand and Gravel aggregate resource management and conservation in northern ireland
Journal of Environmental Management, 1999Co-Authors: Jasper Knight, A M Mccabe, Stephen Mccarron, B SuttonAbstract:Glaciofluvial landforms in Northern Ireland are important resource bodies for Sand and Gravel aggregate, and also form integrated geomorphic assemblages which have scenic and aesthetic importance in the landscape. Determining the overall `value' of Sand and Gravel features in economic and landscape terms involves making assumptions about their geotechnical properties, future extraction rates, and quantifying otherwise poorly-defined aesthetic attributes. This paper deals mainly with landscape economic, scientific and aesthetic `values' and rates of resource depletion on different spatial scales. Based on remote sensing, field mapping and automation of the data set using a geographical information system (GIS), glaciofluvial Sand and Gravel is calculated to cover 534 km(2) +/- 10% in Northern Ireland (similar to 3.4% of land area). By assuming specific deposit thicknesses for each landform type, mappable Sand and Gravel reserves are calculated to range between 2400 and 14 675 million tonnes. Based on low growth, high growth and `business as usual' scenarios of future annual increases in extraction rate from 1996 AD onwards, these reserves are calculated to have a lifespan of 48-314 yr (median value 132 yr). Case studies of the Glarryford esker complex and the Lough Fea deltas complex illustrate the local landscape importance of Sand and Gravel features. These case studies show that defining, quantifying and evaluating landscape resources at a local-scale is a necessary part of aggregate resource management and conservation where the overall resource-base is diminishing. (C) 1999 Academic Press.
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Sand and Gravel aggregate resource management and conservation in Northern Ireland
Journal of Environmental Management, 1999Co-Authors: Jasper Knight, A M Mccabe, Stephen Mccarron, B SuttonAbstract:Abstract Glaciofluvial landforms in Northern Ireland are important resource bodies for Sand and Gravel aggregate, and also form integrated geomorphic assemblages which have scenic and aesthetic importance in the landscape. Determining the overall «value» of Sand and Gravel features in economic and landscape terms involves making assumptions about their geotechnical properties, future extraction rates, and quantifying otherwise poorly-defined aesthetic attributes. This paper deals mainly with landscape economic, scientific and aesthetic «values» and rates of resource depletion on different spatial scales. Based on remote sensing, field mapping and automation of the data set using a geographical information system (GIS), glaciofluvial Sand and Gravel is calculated to cover 534 km 2 ±10% in Northern Ireland (approximately 3·4% of land area). By assuming specific deposit thicknesses for each landform type, mappable Sand and Gravel reserves are calculated to range between 2400 and 14 675 million tonnes. Based on low growth, high growth and «business as usual» scenarios of future annual increases in extraction rate from 1996 AD onwards, these reserves are calculated to have a lifespan of 48–314 yr (median value 132 yr). Case studies of the Glarryford esker complex and the Lough Fea deltas complex illustrate the local landscape importance of Sand and Gravel features. These case studies show that defining, quantifying and evaluating landscape resources at a local-scale is a necessary part of aggregate resource management and conservation where the overall resource-base is diminishing.