Evidence for surface rupture in 1868 on the Hayward fault in north Oakland and major rupturing in prehistoric earthquakes
J. J. Lienkaemper, P. L. Williams
1999, Geophysical Research Letters (26) 1949-1952
WGCEP90 estimated the Hayward fault to have a high probability (0.45 in 30 yr) of producing a future M7 Bay Area earthquake. This was based on a generic recurrence time and an unverified segmentation model, because there were few direct observations for the southern fault and none...
An aerial sightability model for estimating ferruginous hawk population size
L.W. Ayers, S.H. Anderson
1999, Journal of Wildlife Management (63) 85-97
Most raptor aerial survey projects have focused on numeric description of visibility bias without identifying the contributing factors or developing predictive models to account for imperfect detection rates. Our goal was to develop a sightability model for nesting ferruginous hawks (Buteo regalis) that could account for nests missed during aerial...
A spatially distributed energy balance snowmelt model for application in mountain basins
D. Marks, J. Domingo, D. Susong, T. Link, D. Garen
1999, Hydrological Processes (13) 1935-1959
Snowmelt is the principal source for soil moisture, ground-water re-charge, and stream-flow in mountainous regions of the western US, Canada, and other similar regions of the world. Information on the timing, magnitude, and contributing area of melt under variable or changing climate conditions is required...
Historical trends of metals in the sediments of San Francisco Bay, California
Michelle I. Hornberger, S. N. Luoma, A. VanGeen, C. Fuller, R. Anima
1999, Marine Chemistry (64) 39-55
Concentrations of Ag, Al, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn were determined in six sediment cores from San Francisco Bay (SFB) and one sediment core in Tomales Bay (TB), a reference estuary. SFB cores were collected from between the...
Predicting ground-water movement in large mine spoil areas in the Appalachian Plateau
D.R. Wunsch, J.S. Dinger, C.D.R. Graham
1999, International Journal of Coal Geology (41) 73-106
Spoil created by surface mining can accumulate large quantities of ground-water, which can create geotechnical or regulatory problems, as well as flood active mine pits. A current study at a large (4.1 km2), thick, (up to 90 m) spoil body in eastern Kentucky reveals important factors that control the storage...
A new multistage groundwater transport inverse method: presentation, evaluation, and implications
Evan R. Anderman, Mary C. Hill
1999, Water Resources Research (35) 1053-1063
More computationally efficient methods of using concentration data are needed to estimate groundwater flow and transport parameters. This work introduces and evaluates a three‐stage nonlinear‐regression‐based iterative procedure in which trial advective‐front locations link decoupled flow and transport models. Method accuracy and efficiency are evaluated by comparing results to those obtained...
Ground water
Water Resources Division, U.S. Geological Survey
1999, Report
Some water underlies the Earth's surface almost everywhere, beneath hills, mountains, plains, and deserts. It is not always accessible, or fresh enough for use without treatment, and it's sometimes difficult to locate or to measure and describe. This water may occur close to the land surface, as in a marsh,...
The influence of anthropogenic landscape changes on weather in south Florida
R.A. Pielke Sr., R. L. Walko, L. T. Steyaert, P.L. Vidale, G.E. Liston, W.A. Lyons, T.N. Chase
1999, Monthly Weather Review (127) 1663-1672
Using identical observed meteorology for lateral boundary conditions, the Regional Atmospheric Modeling System was integrated for July-August 1973 for south Florida. Three experiments were performed-one using the observed 1973 landscape, another the 1993 landscape, and the third the 1900 landscape, when the region was close to its natural state. Over...
Prediction of episodic acidification in North-eastern USA: An empirical/mechanistic approach
T.D. Davies, M. Tranter, P.J. Wigington Jr., K.N. Eshleman, N.E. Peters, J. Van Sickle, David R. DeWalle, Peter S. Murdoch
1999, Hydrological Processes (13) 1181-1195
Observations from the US Environmental Protection Agency's Episodic Response Project (ERP) in the North-eastern United States are used to develop an empirical/mechanistic scheme for prediction of the minimum values of acid neutralizing capacity (ANC) during episodes. An acidification episode is defined as a hydrological event during which ANC decreases. The...
Aeromagnetic legacy of early Paleozoic subduction along the Pacific margin of Gondwana
Carol A. Finn, D. Moore, D. Damaske, T. Mackey
1999, Geology (27) 1087-1090
Comparison of the aeromagnetic signatures and geology of southeastern Australia and northern Victoria Land, Antarctica, with similar data from ancient subduction zones in California and Japan, provides a framework for reinterpretation of the plate tectonic setting of the Pacific margin of early Paleozoic Gondwana. In our model, the plutons in...
Deaggregation of probabilistic ground motions in the central and eastern United States
S. Harmsen, D. Perkins, A. Frankel
1999, Bulletin of the Seismological Society of America (89) 1-13
Probabilistic seismic hazard analysis (PSHA) is a technique for estimating the annual rate of exceedance of a specified ground motion at a site due to known and suspected earthquake sources. The relative contributions of the various sources to the total seismic hazard are determined as a function of their occurrence rates...
Simulations of snow distribution and hydrology in a mountain basin
Melannie D. Hartman, Jill Baron, Richard B. Lammers, Donald W. Cline, Larry E. Band, Glen E. Liston, Christina L. Tague
1999, Water Resources Research (35) 1587-1603
We applied a version of the Regional Hydro-Ecologic Simulation System (RHESSys) that implements snow redistribution, elevation partitioning, and wind-driven sublimation to Loch Vale Watershed (LVWS), an alpine-subalpine Rocky Mountain catchment where snow accumulation and ablation dominate the hydrologic cycle. We compared simulated discharge to measured discharge and the simulated snow...
Estimates of runoff using water-balance and atmospheric general circulation models
D.M. Wolock, G.J. McCabe
1999, Conference Paper, Journal of the American Water Resources Association
The effects of potential climate change on mean annual runoff in the conterminous United States (U.S.) are examined using a simple water-balance model and output from two atmospheric general circulation models (GCMs). The two GCMs are from the Canadian Centre for Climate Prediction and Analysis (CCC) and the Hadley Centre...
Plate deformation at depth under northern California: Slab gap or stretched slab?
Uri S. ten Brink, N. Shimizu, P.C. Molzer
1999, Tectonics (18) 1084-1098
Plate kinematic interpretations for northern California predict a gap in the underlying subducted slab caused by the northward migration of the Pacific-North America-Juan de Fuca triple junction. However, large-scale decompression melting and asthenospheric upwelling to the base of the overlying plate within the postulated gap are not supported by geophysical...
Geophagy by yellowstone grizzly bears
D.J. Mattson, G.I. Green, R. Swalley
1999, Ursus (11) 109-116
We documented 12 sites in the Yellowstone ecosystem where grizzly bears (Ursus arctos horribilis) had purposefully consumed soil (an activity known as geophagy). We also documented soil in numerous grizzly bear feces. Geophagy primarily occurred at sites barren of vegetation where surficial geology had been modified by geothermal activity. There...
Structure and function of fish communities in the southern Lake Michigan basin with emphasis on restoration of native fish communities
Thomas P. Simon, Paul M. Stewart
1999, Natural Areas Journal (19) 142-154
The southern Lake Michigan basin in northwest Indiana possesses a variety of aquatic habitats including riverine, palustrine, and lacustrine systems. The watershed draining this area is a remnant of glacial Lake Chicago and supports fish communities that are typically low in species richness. Composition of the presettlement Lake Michigan fish...
A closure test for time-specific capture-recapture data
T.R. Stanley, K.P. Burnham
1999, Environmental and Ecological Statistics (6) 197-209
The assumption of demographic closure in the analysis of capture-recapture data under closed-population models is of fundamental importance. Yet, little progress has been made in the development of omnibus tests of the closure assumption. We present a closure test for time-specific data that, in principle, tests the null hypothesis of...
Evaluating sediment chemistry and toxicity data using logistic regression modeling
L.J. Field, D.D. MacDonald, S.B. Norton, C.G. Severn, C.G. Ingersoll
1999, Environmental Toxicology and Chemistry (18) 1311-1322
This paper describes the use of logistic-regression modeling for evaluating matching sediment chemistry and toxicity data. Contaminant- specific logistic models were used to estimate the percentage of samples expected to be toxic at a given concentration. These models enable users to select the probability of effects of concern corresponding to...
Spatial variability of turbulent fluxes in the roughness sublayer of an even-aged pine forest
G. Katul, C.-I. Hsieh, D. Bowling, K. Clark, N. Shurpali, A. Turnipseed, J. Albertson, K. Tu, D. Hollinger, B. M. Evans, B. Offerle, D. Anderson, D. Ellsworth, C. Vogel, R. Oren
1999, Boundary-Layer Meteorology (93) 1-28
The spatial variability of turbulent flow statistics in the roughness sublayer (RSL) of a uniform even-aged 14 m (= h) tall loblolly pine forest was investigated experimentally. Using seven existing walkup towers at this stand, high frequency velocity, temperature, water vapour and carbon dioxide concentrations were measured at 15.5...
Air blasts generated by rockfall impacts: Analysis of the 1996 Happy Isles event in Yosemite National Park
M.M. Morrissey, W. Z. Savage, G. F. Wieczorek
1999, Journal of Geophysical Research B: Solid Earth (104) 23189-23198
The July 10, 1996, Happy Isles rockfall in Yosemite National Park, California, released 23,000 to 38,000 m3 of granite in four separate events. The impacts of the first two events which involved a 550-m free fall, generated seismic waves and atmospheric pressure waves (air blasts). We focus on the dynamic behavior...
Standing crop and sediment production of reef-dwelling foraminifera on O'ahu, Hawai'i
J.N. Harney, P. Hallock, C.H. Fletcher III, B. M. Richmond
1999, Pacific Science (53) 61-73
Most of O'ahu's nearshore and beach sands are highly calcareous and of biogenic origin. The pale-colored constituent grains are the eroded remains of carbonate shells and skeletons produced by marine organisms living atop the island's fringing reefs and in the shallow waters near shore. Previous studies have shown that the...
Integrated numerical modeling for basin-wide water management: The case of the Rattlesnake Creek basin in south-central Kansas
M.A. Sophocleous, J.K. Koelliker, R.S. Govindaraju, T. Birdie, S.R. Ramireddygari, S.P. Perkins
1999, Journal of Hydrology (214) 179-196
The objective of this article is to develop and implement a comprehensive computer model that is capable of simulating the surface-water, ground-water, and stream-aquifer interactions on a continuous basis for the Rattlesnake Creek basin in south-central Kansas. The model is to be used as a tool for evaluating long-term water-management...
Petrology and geochemistry of late-stage intrusions of the A-type, mid-Proterozoic Pikes Peak batholith (Central Colorado, USA): Implications for petrogenetic models
D. R. Smith, J. Noblett, R. A. Wobus, D. Unruh, J. Douglass, R. Beane, C. Davis, S. Goldman, G. Kay, B. Gustavson, B. Saltoun, J. Stewart
1999, Precambrian Research (98) 271-305
The ~1.08 Ga anorogenic, A-type Pikes Peak batholith (Front Range, central Colorado) is dominated by coarse-grained, biotite ?? amphibole syenogranites and minor monzogranites, collectively referred to as Pikes Peak granite (PPG). The batholith is also host to numerous small, late-stage plutons that have been subdivided into two groups (e.g. Wobus,...
Oil, gas field growth projections: Wishful thinking or reality?
E. D. Attanasi, R. F. Mast, D. H. Root
1999, Oil & Gas Journal (97)
The observed `field growth' for the period from 1992 through 1996 with the US Geological Survey's (USGS) predicted field growth for the same period are compared. Known field recovery of field size is defined as the sum of past cumulative field production and the field's proved reserves. Proved reserves are...
The strain in the array is mainly in the plane (waves below ~1 Hz)
J. Gomberg, G. Pavlis, P. Bodin
1999, Bulletin of the Seismological Society of America (89) 1428-1438
We compare geodetic and single-station methods of measuring dynamic deformations and characterize their causes in the frequency bands 0.5-1.0 Hz and 4.0-8.0 Hz. The geodetic approach utilizes data from small-aperture seismic arrays, applying techniques from geodesy. It requires relatively few assumptions and a priori information....
