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Lunar Transient Phenomena: What do the Clementine Images Reveal?
Bonnie J. Buratti, Timothy H. McConnochie, Sascha B. Calkins, John K. Hillier, Kenneth E. Herkenhoff
2000, Icarus (146) 98-117
Lunar Transient Phenomena (LTP) have been reported for at least 450 years. The events range from bright flashes, to reddish or bluish glows, to obscurations. Gaseous spectra and photometric measurements of the events have been obtained. Several theories have been offered as explanations for LTP, including residual volcanic activity or...
Summary of the major water-quality findings from the Eastern Iowa Basins study unit of the National Water-Quality Assessment Program
Stephen J. Kalkhoff
2000, Iowa Groundwater Quarterly (11)
An integrated assessment of the water quality in streams and aquifers in the Wapsipinicon, Iowa, Cedar, and Skunk River basins was conducted in 1996 through 1998 as part of the Eastern Iowa Basins (EIWA) study unit of the U.S. Geological Survey's National Water-Quality Assessment Program (NAWQA). The EIWA study unit...
Transport, behavior, and fate of volatile organic compounds in streams
R. E. Rathbun
2000, Critical Reviews in Environmental Science and Technology (30) 129-295
Volatile organic compounds (VOCs) are compounds with chemical and physical properties that allow the compounds to move freely between the water and air phases of the environment. VOCs are widespread in the environment because of this mobility. Many VOCs have properties that make them suspected or known hazards to the...
Formation of submarine flat-topped volcanic cones in Hawai'i
D. Clague, James G. Moore, J.R. Reynolds
2000, Bulletin of Volcanology (62) 214-233
High-resolution bathymetric mapping has shown that submarine flat-topped volcanic cones, morphologically similar to ones on the deep sea floor and near mid-ocean ridges, are common on or near submarine rift zones of Kilauea, Kohala (or Mauna Kea), Mahukona, and Haleakala volcanoes. Four flat-topped cones on Kohala were explored and sampled...
Volcanism and ice interactions on Earth and Mars
Mary G. Chapman, Carlton C. Allen, Magnus T. Gudmundsson, Virginia C. Gulick, Sveinn P. Jakobsson, Baerbel K. Lucchitta, Ian P. Skilling, Richard B. Waitt
2000, Book chapter, Environmental effects on volcanic eruptions: From deep oceans to deep space
Volcano/ice interactions produce meltwater. Meltwater can enter the groundwater cycle and under the influence of hydrothermal systems, it can be later discharged to form channels and valleys or cycled upward to melt permafrost. Water or ice-saturated ground can erupt into phreatic craters when covered by lava. Violent mixing of meltwater...
Volcanic lake systematics II. Chemical constraints
J.C. Varekamp, G.B. Pasternack, G.L. Rowe Jr.
2000, Book, Journal of Volcanology and Geothermal Research
A database of 373 lake water analyses from the published literature was compiled and used to explore the geochemical systematics of volcanic lakes. Binary correlations and principal component analysis indicate strong internal coherence among most chemical parameters. Compositional variations are influenced by the flux of magmatic volatiles and/or deep hydrothermal...
The state and future of Mars polar science and exploration
S.M. Clifford, D. Crisp, D.A. Fisher, Kenneth E. Herkenhoff, S.E. Smrekar, P.C. Thomas, D. D. Wynn-Williams, R.W. Zurek, J.R. Barnes, B.G. Bills, E.W. Blake, W. M. Calvin, J.M. Cameron, M. H. Carr, P. R. Christensen, B.C. Clark, G.D. Clow, J.A. Cutts, D. Dahl-Jensen, W.B. Durham, F. P. Fanale, J.D. Farmer, F. Forget, K. Gotto-Azuma, R. Grard, R.M. Haberle, W. Harrison, R. Harvey, A.D. Howard, A.P. Ingersoll, P.B. James, J.S. Kargel, H. H. Kieffer, J. Larsen, K. Lepper, M. C. Malin, D. J. McCleese, B. Murray, J.F. Nye, D. A. Paige, S.R. Platt, J.J. Plaut, N. Reeh, J.W. Rice, D.E. Smith, C. R. Stoker, K. L. Tanaka, E. Mosley-Thompson, T. Thorsteinsson, S.E. Wood, A. Zent, M.T. Zuber, H.J. Zwally
2000, Icarus (144) 210-242
As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of ∼106 km2 and total as much as 3–4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to be comparatively young—preserving a...
Ecosystem responses to nitrogen deposition in the Colorado Front Range
Jill Baron, H.M. Rueth, A.M. Wolfe, K. R. Nydick, E.J. Allstott, J.T. Minear, B. Moraska
2000, Ecosystems (3) 352-368
We asked whether 3–5 kg N y−1 atmospheric N deposition was sufficient to have influenced natural, otherwise undisturbed, terrestrial and aquatic ecosystems of the Colorado Front Range by comparing ecosystem processes and properties east and west of the Continental Divide. The eastern side receives elevated N deposition from urban, agricultural,...
Influence of acid volatile sulfides and metal concentrations on metal partitioning in contaminated sediments
J.-S. Lee, B.-G. Lee, S. N. Luoma, H.J. Choi, C.-H. Koh, C. L. Brown
2000, Environmental Science & Technology (34) 4511-4516
The influence of acid volatile sulfide (AVS) on the partitioning of Cd, Ni, and Zn in porewater (PW) and sediment as reactive metals (SEM, simultaneously extracted metals) was investigated in laboratory microcosms. Two spiking procedures were compared, and the effects of vertical geochemical gradients and infaunal activity...
Influence of acid volatile sulfide and metal concentrations on metal bioavailability to marine invertebrates in contaminated sediments
B.-G. Lee, J.-S. Lee, S. N. Luoma, H.J. Choi, C.-H. Koh
2000, Environmental Science & Technology (34) 4517-4523
An 18-day microcosm study was conducted to evaluate the influence of acid volatile sulfides (AVS) and metal additions on bioaccumulation from sediments of Cd, Ni, and Zn in two clams (Macoma balthica and Potamocorbula amurensis) and three marine polychaetes (Neanthes arenaceodentata, Heteromastus filiformis, and Spiophanes missionensis). Manipulation of AVS by oxidation...
Intra- and inter-unit variation in fly ash petrography and mercury adsorption: Examples from a western Kentucky power station
J.C. Hower, R. B. Finkelman, R.F. Rathbone, J. Goodman
2000, Energy and Fuels (14) 212-216
Fly ash was collected from eight mechanical and 10 baghouse hoppers at each of the twin 150-MW wall-fired units in a western Kentucky power station. The fuel burned at that time was a blend of many low-sulfur, high-volatile bituminous Central Appalachian coals. The baghouse ash showed less variation between units...
Surface properties of Mars' polar layered deposits and polar landing sites
Ashwin R. Vasavada, Jean-Pierre Williams, David A. Paige, Kenneth E. Herkenhoff, Nathan T. Bridges, Ronald Greeley, Bruce C. Murray, Deborah S. Bass, Karen S. McBride
2000, Journal of Geophysical Research E: Planets (105) 6961-6969
On December 3, 1999, the Mars Polar Lander and Mars Microprobes will land on the planet's south polar layered deposits near (76°S, 195°W) and conduct the first in situ studies of the planet's polar regions. The scientific goals of these missions address several poorly understood and globally significant issues, such...
The effect of residential development on ground-water quality near Detroit, Michigan
M.A. Thomas
2000, Journal of the American Water Resources Association (36) 1023-1038
Two water-quality studies were done on the outskirts of the Detroit metropolitan area to determine how recent residential development has affected ground-water quality. Pairs of monitor and domestic wells were sampled in areas where residential land use overlies glacial outwash deposits. Young, shallow waters had significantly higher median concentrations of...
Compositing water samples for analysis of volatile organic compounds
T. J. Lopes, J. D. Fallon, T.L. Maluk
2000, Journal of Environmental Engineering (126) 769-773
Accurate mean concentrations of volatile organic compounds (VOCs) can easily and economically be obtained from a single VOC analysis by using proven methods of collecting representative, discrete water samples and compositing them with a gas-tight syringe. The technique can be used in conjunction with chemical analysis by a conventional laboratory,...
Bleached chondrules: Evidence for widespread aqueous processes on the parent asteroids of ordinary chondrites
J. N. Grossman, C. M. O’D. Alexander, Jingyuan Wang, A.J. Brearley
2000, Meteoritics and Planetary Science (35) 467-486
We present the first detailed study of a population of texturally distinct chondrules previously described by Kurat (1969), Christophe Michel-Lévy (1976), and Skinner et al. (1989) that are sharply depleted in alkalis and Al in their outer portions. These “bleached” chondrules, which are exclusively radial pyroxene and cryptocrystalline in texture, have porous...
Large-scale hydrothermal fluid discharges in the Norris-Mammoth corridor, Yellowstone National Park, USA
Y.K. Kharaka, M.L. Sorey, J.J. Thordsen
2000, Book, Journal of Geochemical Exploration
Norris–Mammoth corridor is a complex subsidence structure that extends ∼40 km northward from the 0.6 Ma Yellowstone caldera, and contains many hydrothermal features with high fluid discharges totaling ∼1000 l/s. About 150–250 l/s of hydrothermal water, which attains boiling temperature at surface and 360°C at depth, discharge from the Norris...
A review of the contrasting behavior of two magmatic volatiles: Chlorine and carbon dioxide
J. B. Lowenstern
2000, Conference Paper, Journal of Geochemical Exploration
Chlorine (Cl) and carbon dioxide (CO2) are common magmatic volatiles with contrasting behaviors. CO2 solubility increases with pressure whereas Cl solubility shows relatively little pressure or temperature effect. CO2 speciation changes with silicate melt composition, dissolving as carbonate in basaltic magmas and molecular CO2 in more silicic compositions. In H2O-bearing...
Fumaroles in ice caves on the summit of Mount Rainier: preliminary stable isotope, gas, and geochemical studies
D. R. Zimbelman, R. O. Rye, G. P. Landis
2000, Book, Journal of Volcanology and Geothermal Research
The edifice of Mount Rainier, an active stratovolcano, has episodically collapsed leading to major debris flows. The largest debris flows are related to argillically altered rock which leave areas of the edifice prone to failure. The argillic alteration results from the neutralization of acidic magmatic gases that condense in a...
Whole-lake burdens and spatial distribution of cadmium in sediments of Wisconsin seepage lakes, USA
D.E. Powell, R.G. Rada, J.G. Wiener, G.J. Atchison
2000, Environmental Toxicology and Chemistry (19) 1523-1531
Cadmium was quantified in the surface sediments of six seepage lakes ranging from 8 to 70 ha in surface area, 6 to 20 m in maximum depth, 5.2 to 7.0 in mean epilimnetic pH, and 1.7 to 6.8 mg·L−1 in dissolved organic carbon. Within each lake, dry-weight concentrations of cadmium (range,...
Volatile organic compounds in storm water from a parking lot
T. J. Lopes, J. D. Fallon, D.W. Rutherford, M.H. Hiatt
2000, Journal of Environmental Engineering (126) 1137-1143
A mass balance approach was used to determine the most important nonpoint source of volatile organic compounds (VOCs) in storm water from an asphalt parking lot without obvious point sources (e.g., gasoline stations). The parking lot surface and atmosphere are important nonpoint sources of VOCs, with each being important for...
Enhancements of nonpoint source monitoring of volatile organic compounds in ground water
W.W. Lapham, M.J. Moran, J.S. Zogorski
2000, Journal of the American Water Resources Association (36) 1321-1334
The U.S. Geological Survey (USGS) has compiled a national retrospective data set of analyses of volatile organic compounds (VOCs) in ground water of the United States. The data are from Federal, State, and local nonpoint-source monitoring programs, collected between 1985–95. This data set is being used to augment data...
Carbon dioxide from coal combustion: Variation with rank of US coal
J.C. Quick, D.C. Glick
2000, Fuel (79) 803-812
Carbon dioxide from combustion of US coal systematically varies with ASTM rank indices, allowing the amount of CO2 produced per net unit of energy to be predicted for individual coals. No single predictive equation is applicable to all coals. Accordingly, we provide one equation for coals above high volatile bituminous...
Field testing of passive diffusion bag samplers for volatile organic compound concentrations in ground water, Naval Industrial Reserve Ordnance Plant, Fridley, Minnesota, November 1999 and May 2000
Don A. Vroblesky, Matthew D. Petkewich
2000, Water-Resources Investigations Report 2000-4246
Volatile organic compound concentrations from passive diffusion bag samplers were compared with concentrations from conventional purge (three or more casing volumes) sampling and low-flow purge sampling in side-by-side tests in 17 wells at the Naval Industrial Reserve Ordnance Plant, in Fridley, Minnesota. An initial comparison of 1,2-dichloroethene and trichloroethene concentrations...