Ecological life histories of the three aquatic nuisance plants, Myriophyllum spicatum, Potamogeton crispus and Elodea canadensis
S. A. Nichols, B.H. Shaw
1986, Hydrobiologia (131) 3-21
The life histories of Myriophyllum spicatum L., Elodea canadensis Michx., and Potamogeton crispus L., serious aquatic nuisances in many regions of the world, are reviewed to provide insights into the life style of successful aquatic nuisance plants. Specifically, their distribution and spread in North America; their life cycle, productive and...
VISCOPLASTIC FLUID MODEL FOR DEBRIS FLOW ROUTING.
Cheng-lung Chen
1986, Conference Paper
This paper describes how a generalized viscoplastic fluid model, which was developed based on non-Newtonian fluid mechanics, can be successfully applied to routing a debris flow down a channel. The one-dimensional dynamic equations developed for unsteady clear-water flow can be used for debris flow routing if the flow parameters, such...
Organic geochemical analysis of sedimentary organic matter associated with uranium
J.S. Leventhal, T.A. Daws, J.S. Frye
1986, Applied Geochemistry (1) 241-247
Samples of sedimentary organic matter from several geologic environments and ages which are enriched in uranium (56 ppm to 12%) have been characterized. The three analytical techniqyes used to study the samples were Rock-Eval pyrolysis, pyrolysis-gas chromatography-mass spectrometry, and solid-state C-13...
Radiocarbon studies of latest Pleistocene and Holocene lava flows of the Snake River Plain, Idaho: Data, lessons, interpretations
M. A. Kuntz, E.C. Spiker, M. Rubin, D.E. Champion, R.H. Lefebvre
1986, Quaternary Research (25) 163-176
Latest Pleistocene-Holocene basaltic lava fields of the Snake River Plain, Idaho, have been dated by the radiocarbon method. Backhoe excavations beneath lava flows typically yielded carbon-bearing, charred eolian sediment. This material provided most of the samples for this study; the sediment typically contains less than 0.2% carbon. Charcoal fragments were...
To accrete or not accrete, that is the question
Roland E. von Huene
1986, Geologische Rundschau (75) 1-15
Along modern convergent margins tectonic processes span a spectrum from accretion to erosion. The process of accretion is generally recognized because it leaves a geologic record, whereas the process of erosion is generally hypothetical because it produces a geologic hiatus. Major conditions that determine the dominance of accretion or erosion...
System optimization for the automatic simultaneous determination of arsenic, selenium, and antimony, using hydride generation introduction to an inductively coupled plasma
Grace S. Pyen, Stephen Long, Richard F. Browner
1986, Applied Spectroscopy (40) 246-251
A fixed-size simplex has been used to determine the optimum conditions for the simultaneous determination of arsenic, selenium, and antimony by hydride generation and inductively coupled plasma emission spectrometry. The variables selected for the simplex were carrier gas flow rate, rf power, viewing height, and reagent conditions. The detection limit...
Estimation of distributional parameters for censored trace level water quality data: 1. Estimation techniques
Robert J. Gilliom, Dennis R. Helsel
1986, Water Resources Research (22) 135-146
A recurring difficulty encountered in investigations of many metals and organic contaminants in ambient waters is that a substantial portion of water sample concentrations are below limits of detection established by analytical laboratories. Several methods were evaluated for estimating distributional parameters for such censored data sets using only uncensored observations....
Lateral blasts at Mount St. Helens and hazard zonation
D. R. Crandell, R. Hoblitt
1986, Bulletin of Volcanology (48) 27-37
Lateral blasts at andesitic and dacitic volcanoes can produce a variety of direct hazards, including ballistic projectiles which can be thrown to distances of at least 10 km and pyroclastic density flows which can travel at high speed to distances of more than 30 km. Indirect effect that may accompany...
Some Techniques for Reducing Landslide Hazards
William J. Kockelman
1986, Bulletin of the Association of Engineering Geologists (23) 29-52
Many techniques are available for reducing landslide hazards; 27 are described in this paper. Prerequisites for the successful use of these techniques are hazard information understandable to nongeologists and adequate communication of this information to those who will, or are required to, use it. It is concluded that certain factors...
Determination of total, commonality, and uniqueness of interpreted structural elements from remotely sensed data in Alaska
G.H. Rosenfield
1986, Mathematical Geology (18) 161-179
Statistical analysis is conducted to determine the unique value of real- and synthetic-aperture side-looking airborne radar (SLAR) to detect interpreted structural elements. SLAR images were compared to standard and digitally enhanced Landsat multispectral scanner (MSS) images and to aerial photographs. After interpretation of the imagery, data were cumulated by total...
Summary of pre-1980 tephra-fall deposits erupted from Mount St. Helens, Washington State, USA
D. R. Mullineaux
1986, Bulletin of Volcanology (48) 17-26
Mount St. Helens has been a prolific source of tephra-fall deposits for about 40 000 years. These tephra deposits (1) record numerous explosive eruptions, (2) form important regional time-stratigraphic marker beds, and (3) record repeated changes in composition within and between eruptive periods. Recognized tephra strata record more than 100...
Predicting two-dimensional steady-state soil freezing fronts using the CVBEM
T. V. Hromadka II
1986, Journal of Heat Transfer (108) 235-237
The complex variable boundary element method (CVBEM) is used instead of a real variable boundary element method due to the available modeling error evaluation techniques developed. The modeling accuracy is evaluated by the model-user in the determination of an approximative boundary upon which the CVBEM provides an exact solution. Although...
Estimation of distributional parameters for censored trace level water quality data: 2. Verification and applications
Dennis R. Helsel, Robert J. Gilliom
1986, Water Resources Research (22) 147-155
Estimates of distributional parameters (mean, standard deviation, median, interquartile range) are often desired for data sets containing censored observations. Eight methods for estimating these parameters have been evaluated by R. J. Gilliom and D. R. Helsel (this issue) using Monte Carlo simulations. To verify those findings, the same methods are...
Movement and fate of detergents in groundwater: A field study
E.M. Thurman, L.B. Barber Jr., D. LeBlanc
1986, Journal of Contaminant Hydrology (1) 143-161
The major cations, anions, and detergents in a plume of contaminated groundwater at Otis Air Base on Cape Cod (Mass., U.S.A.) have moved approximately 3.5 km down gradient from the disposal beds. We hypothesize that the detergents form two distinct plumes, which consist of alkyl benzene sulfonates (ABS) detergents and...
Identifying hydraulically conductive fractures with a slow-velocity borehole flowmeter
Alfred E. Hess
1986, Canadian Geotechnical Journal (23) 69-78
The U.S. Geological Survey used a recently developed heat-pulse flowmeter to measure very slow borehole axial water velocities in granitic rock at a site near Lac du Bonnet, Manitoba, Canada. The flowmeter was used with other geophysical measurements to locate and identify hydraulically conducting fractures contributing to the very slow...
Lead-isotopic data from sulfide minerals from the Cascade Range, Oregon and Washington
S. E. Church, A.P. LeHuray, A.R. Grant, M.H. Delevaux, J. E. Gray
1986, Geochimica et Cosmochimica Acta (50) 317-328
Lead-isotopic studies of mineral deposits associated with Tertiary plutons found in the Cascade Range of Oregon and Washington demonstrate a rather uniform isotopic composition in various sulfide minerals (206Pb204Pb= 18.84 to 19.05">206Pb204Pb= 18.84 to 19.05; 207Pb204Pb= 15.57 to 15.62">207Pb204Pb=...
Economic Losses and Fatalities Due to Landslides
Robert L. Schuster, Robert W. Fleming
1986, Bulletin of the Association of Engineering Geologists (23) 11-28
Annual losses in the United States, Japan, Italy, and India have been estimated at 1 billion or more each. During the period 1971-74, nearly 600 people per year were killed by landslides worldwide; about 90 percent of these deaths occurred in the Circum-Pacific region. From 1967-82, 150 people per year...
A new model for humic materials and their interactions with hydrophobic organic chemicals in soil-water or sediment-water systems
R.L. Wershaw
1986, Journal of Contaminant Hydrology (1) 29-45
A generalized model of humic materials in soils and sediments, which is consistent with their observed properties, is presented. This model provides a means of understanding the interaction of hydrophobic pollutants with humic materials. In this model, it is proposed that the humic materials in soils and sediments consist of...
Selective chemical dissolution of sulfides: An evaluation of six methods applicable to assaying sulfide-bound nickel
P.R. Klock, G.K. Czamanske, M. Foose, J. Pesek
1986, Chemical Geology (54) 157-162
Six analytical techniques for the selective chemical dissolution of sulfides are compared with the purpose of defining the best method for accurately determining the concentration of sulfide-bound nickel. Synthesized sulfide phases of known elemental content, mixed with well-analyzed silicates, were used to determine the relative and absolute efficiency, based on...
Phase relations in the CuVS system
D. Wu, L.L.Y. Chang, C.R. Knowles
1986, Journal of the Less-Common Metals (115) 243-251
Phase relations in the system Cu-V-S were studied by using a sealedcapsule technique, reflected-light microscopy, X-ray powder diffraction and electron microprobe analysis. In the temperature range between 300 and 900 ??C, six vanadium sulfides exist in the V-S system. These are VS, V7S8, V3S4, V5S8, V3S5 and VS4. In the...
The solubility of BaCO3(cr) (witherite) in CO2-H2O solutions between 0 and 90°C, evaluation of the association constants of BaHCO3+(aq) and BaCO30(aq) between 5 and 80°C, and a preliminary evaluation of the thermodynamic properties of Ba2+(aq)
Eurybiades Busenberg, Niel Plummer
1986, Geochimica et Cosmochimica Acta (50) 2225-2233
One hundred and fifty new measurements of the solubility of witherite were used to evaluate the equilibrium constant of the reaction BaCO3(cr) = Ba2+(aq) + CO32−(aq) between 0 and 90°C and 1 atm total pressure. The temperature dependence of the equilibrium constant is given by logK = 607.642 + 0.121098T − 20011.25/T − 236.4948 logT where T is in degrees...
Taeniopterid lamina on Phasmatocycas megasporophylls (Cycadales) from the Lower Permian of Kansas, U.S.A.
W.H. Gillespie, H.W. Pfefferkorn
1986, Review of Palaeobotany and Palynology (49) 99-116
New specimens of Phasmatocycas and Taeniopteris from the original Lower Permian locality in Kansas demonstrate organic attachment of the two and corroborate Mamay's hypothesis that Phasmatocycas and Taeniopteris were parts of the same plant. These forms also suggest that cycads evolved from taxa with entire leaves; i.e. Taeniopteris, rather than...
Tectonic and magmatic development of the Great Basin of western United States during the late Cenozoic time.
E.H. McKee, D. C. Noble
1986, Modern Geology (10) 39-49
In the later Cainozoic, approx 18 m.y. ago, the first basin and range faulting developed in the central part of the Great Basin, this extensional tectonic system resulting from drag on the North American plate as the Pacific plate moved obliquely to the NW along the San Andreas fault. The...
Use of detrended correspondence analysis to evaluate factors controlling spatial distribution of benthic insects
H.V. Leland, James L. Carter, Steven V. Fend
1986, Hydrobiologia (131) 113-123
Detrended correspondence analysis (DCA) was evaluated for its effectiveness in displaying factors controlling the spatial distribution of benthic insects in an oligotrophic stream where an experimental gradient (copper) that selectively affects population abundances was imposed. DCA proved to be highly sensitive to differences among samples and consistently provided ecologically meaningful...
Thalenite from Arizona.
J. Fitzpatrick, A. Pabst
1986, American Mineralogist (71) 188-193
Thalenite occurs as a minor constituent of a single small pegmatite within an extensive area of granite a few miles S of Kingman, Arizona. Partly crystalline and partly metamict, this thalenite has composition Y3(Si3O10)(OH), with extensive substitution of Y by REE, especially Dy, Er and Yb. Upon heating, even at...
