Maximum likelihood estimation for the double-count method with independent observers
Bryan F.J. Manly, Lyman L. McDonald, Gerald W. Garner
1996, Journal of Agricultural, Biological, and Environmental Statistics (1) 170-189
Data collected under a double-count protocol during line transect surveys were analyzed using new maximum likelihood methods combined with Akaike's information criterion to provide estimates of the abundance of polar bear (Ursus maritimus Phipps) in a pilot study off the coast of Alaska. Visibility biases were corrected by modeling the...
Spatial partitioning of environmental correlates of avian biodiversity in the conterminous United States
R.J. O’Connor, M.T. Jones, D. White, C. Hunsaker, Tom Loveland, Bruce Jones, E. Preston
1996, Biodiversity Letters (3) 97-110
Classification and regression tree (CART) analysis was used to create hierarchically organized models of the distribution of bird species richness across the conterminous United States. Species richness data were taken from the Breeding Bird Survey and were related to climatic and land use data. We used a systematic spatial grid...
On the coherence of ground motion in the San Fernando valley
S. E. Hough, E. H. Field
1996, Bulletin of the Seismological Society of America (86) 1724-1732
We present an analysis of the coherence of seismic ground motion recorded on alluvial sediments in the San Fernando Valley, California. Using aftershocks of the 17 January 1994 Mw6.7 earthquake recorded at a quasi-dense array of portable stations, we analyze the coherence of three...
Uranium-series disequilibrium, sedimentation, diatom frustules, and paleoclimate change in Lake Baikal
D.N. Edgington, J. A. Robbins, Steven M. Colman, K.A. Orlandini, M.-P. Gustin
1996, Earth and Planetary Science Letters (142) 29-42
The large volume of water, approximately one-fifth of the total surface fresh water on the planet, contained in Lake Baikal in southeastern Siberia is distinguished by having a relatively high concentration of uranium (ca. 2 nM), and, together with the surface...
A Generalized Approach for the Interpretation of Geophysical Well Logs in Ground-Water Studies:Theory and Application
Frederick L. Paillet, R.E. Crowder
1996, Ground Water (34) 883-898
Quantitative analysis of geophysical logs in ground-water studies often involves at least as broad a range of applications and variation in lithology as is typically encountered in petroleum exploration, making such logs difficult to calibrate and complicating inversion problem formulation. At the same time, data inversion and analysis depend on...
Long-term geochemical surveillance of fumaroles at Showa-Shinzan dome, Usu volcano, Japan
R.B. Symonds, Y. Mizutani, Paul H. Briggs
1996, Journal of Volcanology and Geothermal Research (73) 177-211
This study investigates 31 years of fumarole gas and condensate (trace elements) data from Showa-Shinzan, a dacitic dome-cryptodome complex that formed during the 1943-1945 eruption of Usu volcano. Forty-two gas samples were collected from the highest-temperature fumarole, named A-1, from 1954 (800??C) to 1985 (336??C), and from lower-temperature vents. Condensates...
The 40Ar/39Ar and K/Ar dating of lavas from the Hilo 1-km core hole, Hawaii Scientific Drilling Project
W.D. Sharp, B. D. Turrin, P.R. Renne, M. A. Lanphere
1996, Journal of Geophysical Research B: Solid Earth (101) 11607-11616
Mauna Kea lava flows cored in the Hilo hole range in age from <200 ka to about 400 ka based on 40Ar/39Ar incremental heating and K‐Ar analyses of 16 groundmass samples and one coexisting plagioclase. The lavas, all subaerially deposited, include a lower section consisting only of tholeiitic...
Application of ground-penetrating radar to investigation of near-surface fault properties in the San Francisco Bay region
J. Cai, G. A. McMechan, M. A. Fisher
1996, Bulletin of the Seismological Society of America (86) 1459-1470
In many geologic environments, ground-penetrating radar (GPR) provides high-resolution images of near-surface Earth structure. GPR data collection is nondestructive and very economical. The scale of features detected by GPR lies between those imaged by high-resolution seismic reflection surveys and those exposed in trenches...
Site response for urban Los Angeles using aftershocks of the Northridge earthquake
S. Hartzell, A. Leeds, A. Frankel, J. Michael
1996, Bulletin of the Seismological Society of America (86) S168-S192
Ground-motion records from aftershocks of the 1994 Northridge earthquake are used to estimate site response in the urban Los Angeles area. Over 1300 shear-wave records from 61 sources and 90 sites are used in a linear inversion for source and site-response spectra. The...
Regression equations for disinfection by-products for the Mississippi, Ohio and Missouri rivers
R. E. Rathbun
1996, Science of the Total Environment (191) 235-244
Trihalomethane and nonpurgeable total organic-halide formation potentials were determined for the chlorination of water samples from the Mississippi, Ohio and Missouri Rivers. Samples were collected during the summer and fall of 1991 and the spring of 1992 at twelve locations on the Mississippi from New Orleans to Minneapolis, and on...
Velocity structure of a bottom simulating reflector offshore Peru: Results from full waveform inversion
I.A. Pecher, T.A. Minshull, S.C. Singh, Roland E. von Huene
1996, Earth and Planetary Science Letters (139) 459-469
Much of our knowledge of the worldwide distribution of submarine gas hydrates comes from seismic observations of Bottom Simulating Reflectors (BSRs). Full waveform inversion has proven to be a reliable technique for studying the fine structure of BSRs using the compressional wave velocity. We applied a non-linear full waveform inversion...
Estimating the effective spatial resolution of an AVHRR time series
D. J. Meyer
1996, International Journal of Remote Sensing (17) 2971-2980
A method is proposed to estimate the spatial degradation of geometrically rectified AVHRR data resulting from misregistration and off-nadir viewing, and to infer the cumulative effect of these degradations over time. Misregistrations are measured using high resolution imagery as a geometric reference, and pixel sizes are computed directly from satellite...
Factors leading to different viability predictions for a grizzly bear data set
L. S. Mills, S.G. Hayes, M.J. Wisdom, J. Citta, D.J. Mattson, K. Murphy
1996, Conservation Biology (10) 863-873
Population viability analysis programs are being used increasingly in research and management applications, but there has not been a systematic study of the congruence of different program predictions based on a single data set. We performed such an analysis using four population viability analysis computer programs: GAPPS, INMAT, RAMAS/AGE, and...
Improving regional-model estimates of urban-runoff quality using local data
A.B. Hoos
1996, Journal of the American Water Resources Association (32) 855-863
Urban water-quality managers need load estimates of storm-runoff pollutants to design effective remedial programs. Estimates are commonly made using published models calibrated to large regions of the country. This paper presents statistical methods, termed model-adjustment procedures (MAPs), which use a combination of local data and...
Outburst floods from glacier-dammed lakes: The effect of mode of lake drainage on flood magnitude
Joseph S. Walder, John E. Costa
1996, Earth Surface Processes and Landforms (21) 701-723
Published accounts of outburst floods from glacier‐dammed lakes show that a significant number of such floods are associated not with drainage through a tunnel incised into the basal ice—the process generally assumed—but rather with ice‐marginal drainage, mechanical failure of part of the ice dam, or both. Non‐tunnel floods are strongly correlated with...
Testing and validating environmental models
J.W. Kirchner, R. P. Hooper, C. Kendall, C. Neal, G. Leavesley
1996, Science of the Total Environment (183) 33-47
Generally accepted standards for testing and validating ecosystem models would benefit both modellers and model users. Universally applicable test procedures are difficult to prescribe, given the diversity of modelling approaches and the many uses for models. However, the generally accepted scientific principles of documentation and disclosure provide a useful framework...
Shallow velocity structure and Poisson's ratio at the Tarzana, California, strong-motion accelerometer site
R. D. Catchings, W.H.K. Lee
1996, Bulletin of the Seismological Society of America (86) 1704-1713
The 17 January 1994, Northridge, California, earthquake produced strong ground shaking at the Cedar Hills Nursery (referred to here as the Tarzana site) within the city of Tarzana, California, approximately 6 km from the epicenter of the mainshock. Although the Tarzana site is...
The composition of fluid inclusions in ore and gangue minerals from the Silesian-Cracow Mississippi Valley-type Zn-Pb deposits Poland: Genetic and environmental implications
J.G. Viets, A. H. Hofstra, P. Emsbo, A. Kozlowski
1996, Prace - Panstwowego Instytutu Geologicznego (154) 85-103
The composition of fluids extracted from ore and gangue sulfide minerals that span most of the paragenesis of the Silesian-Cracow district was determined using a newly developed ion chromatographic (IC) technique. Ionic species determined were Na+, NH+4, Ca2+, Mg2+, K+, Rb+, Sr2+, Ba2+, Cl-, Br-, F-, I-, PO3-4, CO2-3, HS-,...
Kinetic determinations of trace element bioaccumulation in the mussel Mytilus edulis
W.-X. Wang, N.S. Fisher, S. N. Luoma
1996, Marine Ecology Progress Series (140) 91-113
Laboratory experiments employing radiotracer methodology were conducted to determine the assimilation efficiencies from ingested natural seston, the influx rates from the dissolved phase and the efflux rates of 6 trace elements (Ag, Am, Cd, Co, Se and Zn) in the mussel Mytilus edulis. A kinetic model was then employed to...
Conodont color and surface textural alteration in the Muschelkalk (Triassic) of the Silesian-Cracow Zn-Pb district, Poland
J.E. Repetski, M. Narkiewicz
1996, Prace - Panstwowego Instytutu Geologicznego (154) 112-120
Limestone and dolostone samples were collected from sites within and adjacent to ore zones in the Trzebionka mine, Silesia-Cracow zinc-lead mining district, southern Poland, to assess the level of thermal alteration of the enclosed conodonts, via the color alteration index (CAI) technique, and to study any surface alteration effects on...
Re-evaluation of colorimetric Cl- data from natural waters with DOC
S. A. Norton, M.J. Handlet, J. S. Kahl, N.E. Peters
1996, Water, Air, & Soil Pollution (91) 283-298
Colorimetric Cl- data from natural solutions that contain dissolved organic carbon (DOC) may be biased high. We evaluated aquatic Cl- concentrations in ecosystem compartments at the Bear Brook Watershed, Maine, and from lakes in Maine, using ion chromatography and colorimetry. DOC imparts a positive interference on colorimetric Cl- results proportional...
Kriging: Understanding allays intimidation
Ricardo A. Olea
1996, Fluoride (29) 175-176
In 1938 Daniel Gerhardus "Danie" Krige obtained an undergraduate degree in mining engineering and started a brilliant career centered on analyzing the gold and uranium mines in the Witwatersrand conglomerates of South Africa. He became interested in the disharmony between the poor reliability of reserve estimation reports and the magnitude...
Synthesis of data from studies by the National Irrigation Water-Quality Program
R. L. Seiler
1996, Water Resources Bulletin (32) 1233-1245
From 1986 to 1993, the National Irrigation Water-Quality Program (NIWQP) of the U.S, Department of the Interior studied whether contamination was induced by irrigation drainage in 26 areas of the Western United States. In 1992, a study to evaluate and synthesize data collected during these 26 investigations began. Selenium, boron,...
Mg- and K-bearing borates and associated evaporites at Eagle Borax spring, Death Valley, California: A spectroscopic exploration
J.K. Crowley
1996, Economic Geology (91) 622-635
Efflorescent crusts at the Eagle Borax spring in Death Valley, California, contain an array of rare Mg and K borate minerals, several of which are only known from one or two other localities. The Mg- and/or K-bearing borates include aristarainite, hydroboracite, kaliborite, mcallisterite, pinnoite, rivadavite, and santite. Ulexite and probertite...
Spatial uncertainty analysis: Propagation of interpolation errors in spatially distributed models
D.L. Phillips, D.G. Marks
1996, Ecological Modelling (91) 213-229
In simulation modelling, it is desirable to quantify model uncertainties and provide not only point estimates for output variables but confidence intervals as well. Spatially distributed physical and ecological process models are becoming widely used, with runs being made over a grid of points that represent the landscape. This requires...
