The deethylatrazine/atrazine ratio as an indicator of the onset of the spring flush of herbicides into surface water of the midwestern United States
E.M. Thurman, J. D. Fallon
Hennion M.C.Albaiges J., editor(s)
1996, Conference Paper, International Journal of Environmental Analytical Chemistry
[No abstract available]...
Interaction of productivity and consumption
D.L. DeAngelis, L. Persson, A.D. Rosemond
G.A. Polis, K.O. Winemiller, editor(s)
1996, Book chapter, Food Webs: Integration of patterns and dynamics.
Abstract not supplied at this time...
Indirect effects: Concepts and approaches from ecological theory
D.L. DeAngeis
D.J. Baird, L. Maltby, P.W. Greig-Smith, P. E. T. Douben, editor(s)
1996, Book chapter, Ecotoxicology: Ecological demensions.
Abstract not supplied at this time...
The importance of floodplain forests in the conservation and management of neotropical migratory birds in the Midwest
M. G. Knutson, J.P. Hoover, Erwin E. Klaas
Frank R. Thompson, editor(s)
1996, Book chapter, Management of Midwestern Landscapes for the Conservation of Neotropical Migratory Birds
Bottomland forests of the Central Forest Region of the Upper Midwest are found primarily on the floodplains of large rivers and include at least six types of forest communities. Birds breeding in bottomland forests are affected by extensive variation in latitude, climate, hydrology, forest succession, and change caused by...
Wide angle X-ray scattering (WAXS) study of "two-line" ferrihydrite structure: Effect of arsenate sorption and counterion variation and comparison with EXAFS results
G.A. Waychunas, C. C. Fuller, B.A. Rea, J.A. Davis
1996, Geochimica et Cosmochimica Acta (60) 1765-1781
Wide angle X-ray scattering (WAXS) measurements have been made on a suite of “two-line” ferrihydrite (FHY2) samples containing varying amounts of coprecipitated arsenate. Samples prepared at pH 8 with counter ions chloride, nitrate, and a mixture of both also were examined. The raw WAXS scattering functions show that “two-line” ferrihydrite...
Recent volcanism in the Siqueiros transform fault: Picritic basalts and implications for MORB magma genesis
M.R. Perfit, D.J. Fornari, W.I. Ridley, P.D. Kirk, John F. Casey, K.A. Kastens, J.R. Reynolds, M. Edwards, D. Desonie, R. Shuster, S. Paradis
1996, Earth and Planetary Science Letters (141) 91-108
Small constructional volcanic landforms and very fresh-looking lava flows are present along one of the inferred active strike-slip faults that connect two small spreading centers (A and B) in the western portion of the Siqueiros transform domain. The most primitive lavas (picritic and olivine-phyric basalts), exclusively recovered from the young-looking...
Mobility of 2,2',5,5'-tetrachlorobiphenyl in model systems containing bottom sediments and water from the lower Fox River, Wisconsin
J. F. Elder, R.V. James, J. J. Steuer
1996, Journal of Great Lakes Research (22) 697-706
Sediment-water partitioning and diffusive transport of 2,2’,5,5’-tetrachlorobiphenyl, PCB congener IUPAC #52 (TCB52) were examined in laboratory experiments with sediments from two sites in the lower Fox River, Wisconsin. Native water was pumped at controlled flow rates through cells containing sediments amended...
Global distribution of beryllium isotopes in deep ocean water as derived from Fe-Mn crusts
F. Von Blanckenburg, R. K. O’Nions, N.S. Belshaw, A. Gibb, J.R. Hein
1996, Earth and Planetary Science Letters (141) 213-226
The direct measurement of the ratio of cosmogenic 10Be (T12= 1.5 Ma">T12= 1.5 Ma) to stable terrigenously sourced 9Be in deep seawater or marine deposits can be used to trace water mass movements and to quantify the incorporation of trace metals into the deep sea. In...
Limestone characterization to model damage from acidic precipitation: Effect of pore structure on mass transfer
S.D. Leith, M.M. Reddy, W.F. Irez, M.J. Heymans
1996, Environmental Science & Technology (30) 2202-2210
The pore structure of Salem limestone is investigated, and conclusions regarding the effect of the pore geometry on modeling moisture and contaminant transport are discussed based on thin section petrography, scanning electron microscopy, mercury intrusion porosimetry, and nitrogen adsorption analyses. These investigations are compared to and shown to compliment permeability...
Magnitude and timing of episodic sea-level rise during the last deglaciation
S. D. Locker, A. C. Hine, L.P. Tedesco, E.A. Shinn
1996, Geology (24) 827-830
A succession of elevated ridge deposits on the south Florida margin was mapped using high-resolution seismic and side-scan sonar imaging in water depths ranging from 50 to 124 m. The ridges are interpreted to be subtidal shoal complexes and paleoshorelines (eolian dune or beach) formed during the last sea-level transgression....
Characterizing coal beds in western Kentucky with the Al-La-Sc coherent triad
L.L. Chyi, J.H. Medlin
1996, International Journal of Coal Geology (30) 349-359
Cyclic sedimentation and lateral facies changes make coal bed correlations inconclusive and difficult. This uncertainty can be further complicated if a coal basin has been structurally deformed. Coal macerals can be studied to indicate the nature and degree of coalification. Their use in coal bed correlation, however, is limited. Most...
Chemistry and potential mutagenicity of humic substances in waters from different watersheds in Britain and Ireland
B.E. Watt, Ronald L. Malcolm, M.H.B. Hayes, N.W.E. Clark, J.K. Chipman
1996, Water Research (30) 1502-1516
Humic substances are amorphous organic macromolecules responsible for the hue of natural waters. They are also known to be precursors of mutagens formed on chlorination prior to distribution of drinking water. In this study humic substances from the waters of primary streams, from major rivers, and from reservoirs were isolated...
Use of SAR data to study active volcanoes in Alaska
K.G. Dean, K. Engle, Z. Lu, J. Eichelberger, T. Neal, M. Doukas
1996, European Space Agency, (Special Publication) ESA SP 153-154
Synthetic Aperture Radar (SAR) data of Westdahl, Veniaminof, and Novarupta volcanoes in the Aleutian Arc of Alaska were analyzed to investigate recent surface volcanic processes. These studies support ongoing monitoring and research by the Alaska Volcano Observatory (AVO) in the North Pacific Ocean Region. Landforms and possible crustal deformation before,...
A resource evaluation of the Bakken Formation (Upper Devonian and Lower Mississippian) continuous oil accumulation, Williston Basin, North Dakota and Montana
J. W. Schmoker
1996, Mountain Geologist (33) 1-10
The Upper Devonian and Lower Mississippian Bakken Formation in the United States portion of the Williston Basin is both the source and the reservoir for a continuous oil accumulation - in effect a single very large field - underlying approximately 17,800 mi2 (46,100 km2) of North Dakota and Montana. Within...
Pesticides in streams draining agricultural and urban areas in Colorado
R. A. Kimbrough, D. W. Litke
1996, Environmental Science & Technology (30) 908-916
A study was conducted from April 1993 through April 1994 to describe and compare the occurrence and distribution of pesticides in streams in a small agricultural and a small urban area in Colorado. Twenty-five water samples collected at least monthly at the mouths of two tributary streams of the South...
Temperature-dependent sorption of naphthalene, phenanthrene, and pyrene to low organic carbon aquifer sediments
Joseph J. Piatt, Debera A. Backhus, Paul D. Capel, Steven J. Eisenreich
1996, Environmental Science & Technology (30) 751-760
Sorption experiments were conducted with naphthalene, phenanthrene, and pyrene on low organic carbon sediments at 4 and 26 °C using batch and column techniques. Experimental controls ensured the absence of biologic and photolytic activity and colloid-free solution supernatants. Equilibrium distribution coefficients (Kd) increased 1.1−1.6 times with a decrease in temperature...
Seismic velocities for hydrate-bearing sediments using weighted equation
Myung W. Lee, D. R. Hutchinson, T. S. Collett, William P. Dillon
1996, Journal of Geophysical Research B: Solid Earth (101) 20347-20358
A weighted equation based on the three-phase time-average and Wood equations is applied to derive a relationship between the compressional wave (P wave) velocity and the amount of hydrates filling the pore space. The proposed theory predicts accurate P wave velocities of marine sediments in the porosity range of 40-80%...
Block and shear-zone architecture of the Minnesota River Valley subprovince: Implications for late Archean accretionary tectonics
D. L. Southwick, V.W. Chandler
1996, Canadian Journal of Earth Sciences (33) 831-847
The Minnesota River Valley subprovince of the Superior Province is an Archean gneiss terrane composed internally of four crustal blocks bounded by three zones of east-northeast-trending linear geophysical anomalies. Two of the block-bounding zones are verified regional-scale shears. The geological nature of the third boundary has not been established. Potential-field...
Inferring shallow groundwater flow in saprolite and fractured rock using environmental tracers
P.G. Cook, D. K. Solomon, W. E. Sanford, E. Busenberg, Niel Plummer, R.J. Poreda
1996, Water Resources Research (32) 1501-1509
The Ridge and Valley Province of eastern Tennessee is characterized by (1) substantial topographic relief, (2) folded and highly fractured rocks of various lithologies that have low primary permeability and porosity, and (3) a shallow residuum of medium permeability and high total porosity. Conceptual models of shallow groundwater flow and...
Residence time of water discharging from the Hanging Gardens of Zion Park
B. A. Kimball, P.K. Christensen
1996, Water Resources Bulletin (32) 531-540
The Hanging Gardens are a unique feature of Zion National Park. Knowledge of the source and residence time of water discharging from the Hanging Gardens is necessary to help preserve these features. Ground-water chemical and isotopic data distinguish the discharge from seeps and springs into two groups, one of low...
Gas in the Uinta Basin, Utah - Resources in continuous accumulations
J. W. Schmoker, T. D. Fouch, Ronald R. Charpentier
1996, Mountain Geologist (33) 95-104
Continuous-type gas plays can be envisioned as large areas within which the reservoir rock is everywhere charged with gas. As part of its 1995 National Assessment of oil and gas resources, the U.S. Geological Survey identified four continuous-type gas plays in the Uinta Basin. These occur in sandstone reservoirs of...
The atomic arrangement of iimoriite-(Y), Y2(SiO4)(CO3)
J.M. Hughes, E.E. Foord, J. Jai-Nhuknan, J.M. Bell
1996, Canadian Mineralogist (34) 817-820
Iimoriite-(Y) from Bokan Mountain, Prince of Wales Island, Alaska has been studied using single-crystal X-ray-diffraction techniques. The mineral, ideally Y2(SiO4)(CO3), crystallizes in space group P1, with a 6.5495(13), b 6.6291(14), c 6.4395(11)A??, ?? 116.364(15), ?? 92.556(15) and ?? 95.506(17)??. The atomic arrangement has been solved and refined to an R...
Groundwater origin and dating studies in Szigetkoz
E. Deseo, J. Deak, K. Revesz, J.K. Bohlke, M. Stute
1996, Acta Geologica Hungarica (39 Suppl.) 31-34
No abstract available....
Pesticides and pesticide degradation products in stormwater runoff: Sacramento River Basin, California
Joseph L. Domagalski
1996, Water Resources Bulletin (32) 953-964
Pesticides in stormwater runoff, within the Sacramento River Basin, California, were assessed during a storm that occurred in January 1994. Two organophosphate insecticides (diazinon and methidathion), two carbamate pesticides (molinate and carbofuran), and one triazine herbicide (simazine) were detected. Organophosphate pesticide concentrations increased with the rising stage of the hydrographs;...
Evaluating the reliability of the stream tracer approach to characterize stream-subsurface water exchange
Judson W. Harvey, Brian J. Wagner, Kenneth E. Bencala
1996, Water Resources Research (32) 2441-2451
Stream water was locally recharged into shallow groundwater flow paths that returned to the stream (hyporheic exchange) in St. Kevin Gulch, a Rocky Mountain stream in Colorado contaminated by acid mine drainage. Two approaches were used to characterize hyporheic exchange: sub-reach-scale measurement of hydraulic heads and hydraulic conductivity to compute...
