The mechanics of unrest at Long Valley caldera, California: 1. Modeling the geometry of the source using GPS, leveling and two-color EDM data
Maurizio Battaglia, P. Segall, J. Murray, Peter Cervelli, J. Langbein
2003, Journal of Volcanology and Geothermal Research (127) 195-217
We surveyed 44 existing leveling monuments in Long Valley caldera in July 1999, using dual frequency global positioning system (GPS) receivers. We have been able to tie GPS and leveling to a common reference frame in the Long Valley area and computed the vertical deformation by differencing GPS-based and leveled...
Tidal truncation and barotropic convergence in a channel network tidally driven from opposing entrances
J.C. Warner, D. Schoellhamer, G. Schladow
2003, Estuarine, Coastal and Shelf Science (56) 629-639
Residual circulation patterns in a channel network that is tidally driven from entrances on opposite sides are controlled by the temporal phasing and spatial asymmetry of the two forcing tides. The Napa/Sonoma Marsh Complex in San Francisco Bay, CA, is such a system. A sill on the west entrance to...
Pore space analysis of NAPL distribution in sand-clay media
D. Matmon, N.J. Hayden
2003, Advances in Water Resources (26) 773-785
This paper introduces a conceptual model of clays and non-aqueous phase liquids (NAPLs) at the pore scale that has been developed from a mathematical unit cell model, and direct micromodel observation and measurement of clay-containing porous media. The mathematical model uses a unit cell concept with uniform spherical grains for...
A proposed coast-wide reference monitoring system for evaluating Wetland restoration trajectories in Louisiana
G.D. Steyer, C.E. Sasser, J.M. Visser, E.M. Swenson, J.A. Nyman, R.C. Raynie
2003, Environmental Monitoring and Assessment (81) 107-117
Wetland restoration efforts conducted in Louisiana under the Coastal Wetlands Planning, Protection and Restoration Act require monitoring the effectiveness of individual projects as well as monitoring the cumulative effects of all projects in restoring, creating, enhancing, and protecting the coastal landscape. The effectiveness of the traditional paired-reference monitoring approach in...
Aggradation of gravels in tidally influenced fluvial systems: Upper Albian (Lower Cretaceous) on the cratonic margin of the North American Western Interior foreland basin
Richard L. Brenner, Greg A. Ludvigson, B.L. Witzke, P.L. Phillips, T. S. White, David F. Ufnar, Luis A. Gonzalez, R. M. Joeckel, A. Goettemoeller, B.R. Shirk
2003, Cretaceous Research (24) 439-448
Alluvial conglomerates were widely distributed around the margin of the Early Cretaceous North American Cretaceous Western Interior Seaway (KWIS). Conglomerates, sandstones, and lesser amounts of mudstones of the upper Albian Nishnabotna Member of the Dakota Formation were deposited as fill-in valleys that were incised up to 80 m into upper...
Local extinction and turnover rates at the edge and interior of species' ranges
P.F. Doherty Jr., T. Boulinier, D. Nichols James. Nichols
2003, Conference Paper, Annales Zoologici Fennici
One hypothesis for the maintenance of the edge of a species' range suggests that more central (and abundant) populations are relatively stable and edge populations are less stable with increased local extinction and turnover rates. To date, estimates of such metrics are equivocal due to design and analysis flaws. Apparent...
Molecular epidemiology of infectious hematopoietic necrosis virus reveals complex virus traffic and evolution within southern Idaho aquaculture
R.M. Troyer, Gael Kurath
2003, Diseases of Aquatic Organisms (55) 175-185
Infectious hematopoietic necrosis virus (IHNV) is a rhabdovirus which infects salmon and trout and may cause disease with up to 90% mortality. In the Hagerman Valley of Idaho, IHNV is endemic or epidemic among numerous fish farms and resource mitigation hatcheries. A previous study characterizing the genetic diversity among 84...
Modeling soil thermal and carbon dynamics of a fire chronosequence in interior Alaska
Q. Zhuang, A. D. McGuire, K. P. O’Neill, J.W. Harden, V.E. Romanovsky, J. Yarie
2003, Journal of Geophysical Research D: Atmospheres (108) FFR 3-1-FFR 3-26
In this study, the dynamics of soil thermal, hydrologic, and ecosystem processes were coupled to project how the carbon budgets of boreal forests will respond to changes in atmospheric CO2, climate, and fire disturbance. The ability of the model to simulate gross primary production and ecosystem respiration was verified for...
Living on the edge: Distribution of Dungeness crab Cancer magister in a recently deglaciated fjord
S. James Taggart, P.N. Hooge, Jennifer Mondragon, Elizabeth Ross Hooge, A.G. Andrews
2003, Marine Ecology Progress Series (246) 241-252
Glacier Bay, Alaska, has supported a productive Dungeness crab fishery, although the area where the fishery occurred was small relative to the remainder of the Bay. We hypothesized that 1 or more abiotic limiting factors prevented crabs from surviving in the upper Bay. We tested this hypothesis by systematically sampling...
Characterization of microbially Fe(III)-reduced nontronite: Environmental cell-transmission electron microscopy study
Jin-wook Kim, Yoko Furukawa, Tyrone L. Daulton, Dawn L. Lavoie, Steven W. Newell
2003, Clays and Clay Minerals (51) 382-389
Microstructural changes induced by the microbial reduction of Fe(III) in nontronite by Shewanella oneidensis were studied using environmental cell (EC)-transmission electron microscopy (TEM), conventional TEM, and X-ray powder diffraction (XRD). Direct observations of clays by EC-TEM in their hydrated state allowed for the first time an accurate and unambiguous TEM...
A predictive risk model for electroshock-induced mortality of the endangered Cape Fear shiner
F.M. Holliman, J.B. Reynolds, T.J. Kwak
2003, North American Journal of Fisheries Management (23) 905-912
We evaluated the effects of a single electroshock on injury and mortality of hatchery-reared Cape Fear shiners Notropis mekistocholas (N = 517), an endangered cyprinid. Groups of 18-22 Cape Fear shiners were exposed to DC, 120-Hz pulsed DC (PDC), or 60-Hz PDC at voltage gradients of 1.1, 1.9, or 2.7...
Gravity and magnetic expression of the San Leandro gabbro with implications for the geometry and evolution of the Hayward Fault zone, northern California
D. A. Ponce, T.G. Hildenbrand, R.C. Jachens
2003, Bulletin of the Seismological Society of America (93) 14-26
The Hayward Fault, one of the most hazardous faults in northern California, trends north-northwest and extends for about 90 km along the eastern San Francisco Bay region. At numerous locations along its length, distinct and elongate gravity and magnetic anomalies correlate with mapped mafic and ultramafic rocks. The most prominent...
Temporal species richness-biomass relationships along successional gradients
Q. Guo
2003, Journal of Vegetation Science (14) 121-128
Diversity-biomass relationships are frequently reported to be hump-shaped over space at a given time. However, it is not yet clear how diversity and biomass change simultaneously and how they are related to each other overtime (e.g. in succession) at one locality. This study develops a temporal model based on the...
Taking the pulse of mountains: Ecosystem responses to climatic variability
Daniel B. Fagre, David L. Peterson, Amy E. Hessl
2003, Climatic Change (59) 263-282
An integrated program of ecosystem modeling and field studies in the mountains of the Pacific Northwest (U.S.A.) has quantified many of the ecological processes affected by climatic variability. Paleoecological and contemporary ecological data in forest ecosystems provided model parameterization and validation at broad spatial and temporal scales for tree growth,...
Empirical ground-motion relations for subduction-zone earthquakes and their application to Cascadia and other regions
G. M. Atkinson, D.M. Boore
2003, Bulletin of the Seismological Society of America (93) 1703-1729
Ground-motion relations for earthquakes that occur in subduction zones are an important input to seismic-hazard analyses in many parts of the world. In the Cascadia region (Washington, Oregon, northern California, and British Columbia), for example, there is a significant hazard from megathrust earthquakes along the subduction interface and from large...
Arctic transitions in the Land - Atmosphere System (ATLAS): Background, objectives, results, and future directions
A. D. McGuire, M. Sturm, F. S. Chapin III
2003, Journal of Geophysical Research D: Atmospheres (108)
This paper briefly reviews the background, objectives, and results of the Arctic Transitions in the Land-Atmosphere System (ATLAS) Project to date and provides thoughts on future directions. The key goal of the ATLAS Project is to improve understanding of controls over spatial and temporal variability of terrestrial processes in the...
Age of the Mono Lake excursion and associated tephra
L. Benson, J. Liddicoat, J. Smoot, A. Sarna-Wojcicki, R. Negrini, S. Lund
2003, Quaternary Science Reviews (22) 135-140
The Mono Lake excursion (MLE) is an important time marker that has been found in lake and marine sediments across much of the Northern Hemisphere. Dating of this event at its type locality, the Mono Basin of California, has yielded controversial results with the most recent effort concluding that the...
Bayesian Estimations of Peak Ground Acceleration and 5% Damped Spectral Acceleration from Modified Mercalli Intensity Data
J.E. Ebel, D.J. Wald
2003, Earthquake Spectra (19) 511-529
We describe a new probabilistic method that uses observations of modified Mercalli intensity (MMI) from past earthquakes to make quantitative estimates of ground shaking parameters (i.e., peak ground acceleration, peak ground velocity, 5% damped spectral acceleration values, etc.). The method uses a Bayesian approach to make quantitative estimates of the...
Impacts of the Columbia River hydroelectric system on main-stem habitats of fall chinook salmon
D.D. Dauble, T.P. Hanrahan, D.R. Geist, M.J. Parsley
2003, North American Journal of Fisheries Management (23) 641-659
Salmonid habitats in main-stem reaches of the Columbia and Snake rivers have changed dramatically during the past 60 years because of hydroelectric development and operation. Only about 13% and 58% of riverine habitats in the Columbia and Snake rivers, respectively, remain. Most riverine habitat is found in the upper Snake...
Liquefaction potential index: Field assessment
S. Toprak, T.L. Holzer
2003, Journal of Geotechnical and Geoenvironmental Engineering (129) 315-322
Cone penetration test (CPT) soundings at historic liquefaction sites in California were used to evaluate the predictive capability of the liquefaction potential index (LPI), which was defined by Iwasaki et al. in 1978. LPI combines depth, thickness, and factor of safety of liquefiable material inferred from a CPT sounding into...
Identification of linear and threshold responses in streams along a gradient of urbanization in Anchorage, Alaska
Robert T. Ourso, S.A. Frenzel
2003, Hydrobiologia (501) 117-131
We examined biotic and physiochemical responses in urbanized Anchorage, Alaska, to the percent of impervious area within stream basins, as determined by high-resolution IKONOS satellite imagery and aerial photography. Eighteen of the 86 variables examined, including riparian and instream habitat, macroinvertebrate communities, and water/sediment chemistry, were significantly correlated with percent...
Hilbert-Huang transform analysis of dynamic and earthquake motion recordings
R.R. Zhang, S. Ma, E. Safak, S. Hartzell
2003, Journal of Engineering Mechanics (129) 861-875
This study examines the rationale of Hilbert-Huang transform (HHT) for analyzing dynamic and earthquake motion recordings in studies of seismology and engineering. In particular, this paper first provides the fundamentals of the HHT method, which consist of the empirical mode decomposition (EMD) and the Hilbert spectral analysis. It then uses...
Lake Clark sockeye salmon population assessment
Carol Ann Woody, Kristina M. Ramstad, Daniel B. Young, G. Kevin Sage, Fred W. Allendorf
2003, Report
Radio telemetry was used to identify and map sockeye salmon spawning habitats in glacially influenced Lake Clark, Kvichak River watershed, Alaska. Two hundred eighty-two adult sockeye salmon were radio tagged and tracked to spawning grounds. Thirty-five spawning areas were identified, including 18 previously unidentified. Comparison of radio telemetry data with...
The Impact of Turtle Excluder Devices and Fisheries Closures on Loggerhead and Kemp's Ridley Strandings in the Western Gulf of Mexico
R.L. Lewison, L.B. Crowder, D.J. Shaver
2003, Conservation Biology (17) 1089-1097
The Sea Turtle Stranding and Salvage Network has been monitoring turtle strandings for more than 20 years in the United States. High numbers of strandings in the early to mid-1980s prompted regulations to require turtle excluder devices (TEDs) on shrimping vessels (trawlers). Following year-round TED implementation in 1991, however, stranding...
Mercury methylation in mine wastes collected from abandoned mercury mines in the USA
J. E. Gray, M.E. Hines, H. Biester, B.K. Lasorsa
Boutron C.Ferrari C., editor(s)
2003, Conference Paper, Journal De Physique. IV : JP
Speciation and transformation of Hg was studied in mine wastes collected from abandoned Hg mines at McDermitt, Nevada, and Terlingua, Texas, to evaluate formation of methyl-Hg, which is highly toxic. In these mine wastes, we measured total Hg and methyl-Hg contents, identified various Hg compounds using a pyrolysis technique, and...
