Herbicides in streams. Midwestern United States
Donald A. Goolsby, E. Michael Thurman, Dana W. Kolpin
1991, Conference Paper
Results from a 2-year study of 149 streams geographically distributed across the corn-producing region of 10 midwestern States show that detectable concentrations of herbicides persist year round in most streams. Some herbicides exceeded proposed maximum contaminant levels for drinking water for periods of several weeks to several months following application....
Some current themes in physical hydrology of the land-atmosphere interface
P. C. D. Milly
1991, Conference Paper, IAHS Publication (International Association of Hydrological Sciences)
Certain themes arise repeatedly in current literature dealing with the physical hydrology of the interface between the atmosphere and the continents. Papers contributed to the 1991 International Association of Hydrological Sciences Symposium on Hydrological Interactions between Atmosphere, Soil and Vegetation echo these themes, which are discussed in this paper. The...
Fossil and active fumaroles in the 1912 eruptive deposits, Valley of ten thousand smokes, Alaska
T. E. C. Keith
1991, Journal of Volcanology and Geothermal Research (45) 227-254
Fumaroles in the ash-flow sheet emplaced during the 1912 eruption of Novarupta were intensely active throughout the Valley of Ten Thousand Smokes (VTTS) when first studied in 1917. Fumarole temperatures recorded in 1919 were as hot as 645??C. Influx of surface waters into the hot ash-flow sheet provided the fluid...
Evolution of deep structure along the trans-Alaska crustal transect, Chugach Mountains and Copper River Basin, southern Alaska
G. S. Fuis, George Plafker
1991, Journal of Geophysical Research (96) 4229-4253
One of the most important results of the Trans-Alaska Crustal Transect investigations is the discovery that more than one third of the North American plate in southern Alaska (Chugach Mountains and Copper River basin) consists of tectonically underplated oceanic lithosphere. In southern Alaska, exposed accreted...
Coupled surface-water and ground-water model
Eric D. Swain, Eliezer J. Wexler
1991, Conference Paper
In areas with dynamic and hydraulically well connected ground-water and surface-water systems, it is desirable that stream-aquifer interaction be simulated with models of equal sophistication and accuracy. Accordingly, a new, coupled ground-water and surface-water model was developed by combining the U.S. Geological Survey models MODFLOW and BRANCH. MODFLOW is the...
Paleoshorelines, reefs, and a rising sea: South Florida, USA
B. H. Lidz, E.A. Shinn
1991, Journal of Coastal Research (7) 203-229
The porous limestone bedrock, thin sediment cover, and tectonic stability of the Florida Platform during the past 15 ka BP provide an exceptionally suitable setting for reconstruction of paleoshorelines and onshore projection of future shorelines in a rising-sea scenario. Paleoshorelines for 8, 6, 4 and 2 ka BP show that...
Development and application of a hillslope hydrologic model
C. A. Blain, P. C. D. Milly
1991, Advances in Water Resources (14) 168-174
A vertically integrated two-dimensional lateral flow model of soil moisture has been developed. Derivation of the governing equation is based on a physical interpretation of hillslope processes. The lateral subsurface-flow model permits variability of precipitation and evapotranspiration, and allows arbitrary specification of soil-moisture retention properties. Variable slope, soil thickness, and...
Boron analysis by electron microprobe using MoB4C layered synthetic crystals
J. J. McGee, J. F. Slack, C.R. Herrington
1991, American Mineralogist (76) 681-684
Preliminary electron microprobe studies of B distribution in minerals have been carried out using MoB4C-layered synthetic crystals to improve analytical sensitivity for B. Any microprobe measurements of the B contents of minerals using this crystal must include analyses for Cl to assess and correct for the interference of Cl X-rays...
Conditions leading to a recent small hydrothermal explosion at Yellowstone National Park
R.O. Fournier, J. M. Thompson, C. G. Cunningham, R. A. Hutchinson
1991, Geological Society of America Bulletin (103) 1114-1120
Porkchop Geyser, in Yellowstone National Park, was the site of a small hydrothermal explosion on September 5, 1989. In the early 1960s, this was a quiescent spring with an intermittent seeping discharge. Infrequent geyser eruptions 3-5 m high started in 1971, and in 1985 the geyser began erupting as a...
The last interglaciation in Alaska: Stratigraphy and paleoecology of potential sites
T. D. Hamilton, J. Brigham-Grette
1991, Quaternary International (10-12) 49-71
At least 20 localities in Alaska contain deposits that may provide information on the last interglaciation (Oxygen-Isotope Substage 5e). These widely dispersed localities include river bluffs, coastal bluffs and terraces, elevated marine shorelines, lake basins, and artificial excavations. Most of the inferred interglacial deposits contain macrofossils or pollen that are...
Underwater observations of active lava flows from Kilauea volcano, Hawaii
G.W. Tribble
1991, Geology (19) 633-636
Underwater observation of active submarine lava flows from Kilauea volcano, Hawaii, in March-June 1989 revealed both pillow lava and highly channelized lava streams flowing down a steep and unconsolidated lava delta. The channelized streams were 0.7-1.5 m across and moved at rates of...
Volcanic episodes near Yucca Mountain as determined by paleomagnetic studies at Lathrop Wells, Crater Flat, and Sleeping Butte, Nevada
Duane E. Champion
Anon, editor(s)
1991, Conference Paper, High Level Radioactive Waste Management
It has been suggested that mafic volcanism in the vicinity of Yucca Mountain, Nev., is both recent (20 ka) and a product of complex 'polycyclic' eruptions. This pattern of volcanism, as interpreted by some workers at the Lathrop Wells volcanic complex, comprises a sequence of numerous small-volume eruptions that become...
Fate of acetone in an outdoor model stream with a nitrate supplement, southern Mississippi, U.S.A.
R. E. Rathbun, D. W. Stephens, D. Y. Tai
1991, Journal of Hydrology (123) 225-242
The fate of acetone in an outdoor model stream to which nitrate was added as a nutrient supplement was determined. The stream, in southern Mississippi, U.S.A. was 234 m long. Water was supplied to the stream by an artesian well at about 1.21 s−1, resulting in a mean water velocity...
Tidal stirring and phytoplankton bloom dynamics in an estuary
J. E. Cloern
1991, Journal of Marine Research (49) 203-221
In South San Francisco Bay, estuarine phytoplankton biomass fluctuates at the time scale of days to weeks; much of this variability is associated with fluctuations in tidal energy. During the spring seasons of every year from 1980-1990, episodic blooms occurred in which phytoplankton biomass rose from a baseline of 2-4mg...
Origin of late dolomite cement by CO2-saturated deep basin brines: evidence from the Ozark region, central United States
D. L. Leach, G.S. Plumlee, A. H. Hofstra, G. P. Landis, E. L. Rowan, J.G. Viets
1991, Geology (19) 348-351
Studies of fluid inclusions in regionally extensive late dolomite cement (LDC) throughout the Ozark region show that CO2 effervescence was widespread during dolomite precipitation. On the basis of quantitative analyses of inclusion fluids, reaction-path modeling shows that LDC with trace amounts of sulfides can...
Leaching of 226Ra from components of uranium mill tailings
E. R. Landa
1991, Hydrometallurgy (26) 361-368
A sequential extraction procedure was used to characterize the geochemical forms of 226Ra retained by mixtures of quartz sand and a variety of fine-grained rock and mineral species. These mixtures had previously been exposed to the sulfuric acid milling liquor of a simulated acid-leach uranium milling circuit. For most test cases,...
Caution on the use of Viton® or FETFE® O-rings in carbon dioxide sample containers for δ180 analysis
Kinga M. Revesz, Tyler B. Coplen
1991, Chemical Geology: Isotope Geoscience Section (86) 259-261
After 10 days, 3-μmol CO2 samples in containers having glass stopcocks with Viton® or FETFE O-rings were enriched in 18O by 1.5% as a result of absorption by the elastomer; this amount of enrichment is ∼20 times greater than the precision of δ18O measurements of most laboratories. No change in 13C content was observed....
Publication aspects of ethics in photogrammetry
Morris M. Thompson
1991, Photogrammetric Engineering and Remote Sensing (57) 161-162
According to the Code of Ethics of the American Society for Photogrammetry and Remote Sensing (ASPRS), the principles on which ethics are founded consist of honesty, justice, and courtesy, forming a moral philosophy associated with mutual interest among men. We will cover in particular the ethical problems of publication of...
Captive breeding and reintroduction of the endangered masked bobwhite
J. W. Carpenter, R. R. Gabel, J.G. Goodwin
1991, Zoo Biology (10) 439-449
Efforts to restore the endangered masked bobwhite (Colinus virginianus ridgwayi) to its former range have required 1) habitat acquisition, restoration, and preservation; 2) captive propagation; and 3) reintroduction of captive-bred stock. In its role to recover the masked bobwhite, the Patuxent Wildlife Research Center (U.S. Fish and Wildlife Service) has...
Fault stability inferred from granite sliding experiments at hydrothermal conditions
M.L. Blanpied, D.A. Lockner, J.D. Byerlee
1991, Geophysical Research Letters (18) 609-612
Seismicity on crustal faults is concentrated in the depth interval 1–3 to 12–15km. Tse and Rice (1986) suggested that the lower bound on seismicity is due to a switch with increasing temperature from velocity weakening (destabilizing) to velocity strengthening (stabilizing) friction. They inferred this transition from friction data for dry...
Subalkaline andesite from Valu Fa Ridge, a back-arc spreading center in southern Lau Basin: petrogenesis, comparative chemistry, and tectonic implications
T.L. Vallier, G.A. Jenner, F.A. Frey, J.B. Gill, A. S. Davis, A.M. Volpe, J.W. Hawkins, J.D. Morris, Peter A. Cawood, J. L. Morton, D.W. Scholl, M. Rautenschlein, W.M. White, Ross W. Williams, A.J. Stevenson, L. D. White
1991, Chemical Geology (91) 227-256
Tholeiitic andesite was dredged from two sites on Valu Fa Ridge (VFR), a back-arc spreading center in Lau Basin. Valu Fa Ridge, at least 200 km long, is located 40-50 km west of the active Tofua Volcanic Arc (TVA) axis and lies about 150 km above the subducted oceanic plate....
Large-scale variation in lithospheric structure along and across the Kenya rift
C. Prodehl, J. Mechie, W. Kaminski, K. Fuchs, C. Grosse, H. Hoffmann, R. Stangl, R. Stellrecht, M.A. Khan, Peter K.H. Maguire, W. Kirk, Gordon R. Keller, A. Githui, M. Baker, Walter D. Mooney, E. Criley, J. Luetgert, B. Jacob, H. Thybo, M. Demartin, S. Scarascia, A. Hirn, J. R. Bowman, I. Nyambok, S. Gaciri, J. Patel, E. Dindi, D.H. Griffiths, R.F. King, A. E. Mussett, L.W. Braile, G. Thompson, K. Olsen, S. Harder, R. Vees, D. Gajewski, A. Schulte, J. Obel, F. Mwango, J. Mukinya, D. Riaroh
1991, Nature (354) 223-227
The Kenya rift is one of the classic examples of a continental rift zone: models for its evolution range from extension of the lithosphere by pure shear1, through extension by simple shear2, to diapiric upwelling of an asthenolith3. Following a pilot study in 19854, the present work involved the shooting...
Marinas, mines, and mudpots. Building a feature-based production system at the U.S. geological survey
Gary B. Chappell, Kathryn C. Neff
1991, Conference Paper, GIS/LIS 1991 ACSM-ASPRS Fall Convention
By the mid-1990's, the U.S. Geological Survey expects to produce spatial data according to its new data model, Digital Line Graph-Enhanced (DLG-E). This new data model currently defines more than 200 unique feature types that describe the geographic phenomena portrayed on the series of 1:24,000-scale topographic maps. Characteristics of features...
Wading measurements of vertical velocity profiles
R.D. Jarrett
1991, Geomorphology (4) 243-247
Increasingly, there is a recognized need to enhance research of hydraulic, geomorphic and sediment-transport processes in rivers. This research often includes studies of the velocity distribution in rivers. This paper describes the use of the topsetting wading rod and a table and...
Differentiation of colloidal and dissolved silica: Analytical separation using spectrophotometry and inductively coupled plasma atomic emission spectrometry
A. Lewis-Russ, J. Ranville, A.T. Kashuba
1991, Analytica Chimica Acta (249) 509-511
A method is described that differentiates between solutions containing silica-dominated colloids and solutions that are essentially free of colloids. Suspensions of tuff particles were treated to remove colloids by centrifugation, filtration or both. Agreement of silica concentrations determined by inductively coupled plasma atomic emission spectrometry and by a spectrophotometric method...
