3D near-to-surface conductivity reconstruction by inversion of VETEM data using the distorted Born iterative method
G.L. Wang, W.C. Chew, T.J. Cui, A.A. Aydiner, D.L. Wright, D.V. Smith
2004, Inverse Problems (20)
Three-dimensional (3D) subsurface imaging by using inversion of data obtained from the very early time electromagnetic system (VETEM) was discussed. The study was carried out by using the distorted Born iterative method to match the internal nonlinear property of the 3D inversion problem. The forward solver was based on the...
An integrated geospatial approach to monitoring the Bering Glacier system, Alaska
E.G. Josberger, J. Payne, S. Savage, R. Shuchman, G. Meadows
2004, Conference Paper, International Geoscience and Remote Sensing Symposium (IGARSS)
The Bering Glacier is the largest and longest glacier in continental North America, with an area of approximately 5,175 km2, and a length of 190 km. It is also the largest surging glacier in America, having surged at least five times during the twentieth century. The last surge of the...
The Coso geothermal area: A laboratory for advanced MEQ studies for geothermal monitoring
B.R. Julian, G.R. Foulger, K. Richards-Dinger
2004, Conference Paper, Geothermal Resources Council Transactions
The permanent 16-station network of three-component digital seismometers at the Coso geothermal area, California, supplemented by 14 temporary instruments deployed in connection with the DOE Enhanced Geothermal Systems (EGS) Project, provides high-quality microearthquake (MEQ) recordings that are well suited to monitoring a producing geothermal area. We are currently using these...
A method for evaluating the importance of system state observations to model predictions, with application to the Death Valley regional groundwater flow system
Claire R. Tiedeman, D. Matthew Ely, Mary C. Hill, Grady M. O’Brien
2004, Water Resources Research (40)
We develop a new observation‐prediction (OPR) statistic for evaluating the importance of system state observations to model predictions. The OPR statistic measures the change in prediction uncertainty produced when an observation is added to or removed from an existing monitoring network, and it can be used to guide refinement and...
Modification of pure oxygen absorption equipment for concurrent stripping of carbon dioxide
B.J. Watten, P.L. Sibrell, G.A. Montgomery, S.M. Tsukuda
2004, Conference Paper, Aquacultural Engineering
The high solubility of carbon dioxide precludes significant desorption within commercial oxygen absorption equipment. This operating characteristic of the equipment limits its application in recirculating water culture systems despite its ability to significantly increase allowable fish loading rates (kg/(L min)). Carbon dioxide (DC) is typically removed by air stripping. This...
Preliminary results of a dam-removal analysis on brewster creek near st. Charles, Illinois, 2002-2004
K.M. Kosky, T. D. Straub, D.P. Roseboom, G.P. Johnson
D'Ambrosio J.L., editor(s)
2004, Conference Paper, Proceedings of the 2004 Self-Sustaining Solutions for Streams, Wetlands, and Watersheds Conference
The benefits of gradually removing a dam (through multiple notches) are to reduce the total project cost and reduce possible environmental effects by allowing the impounded sediment to slowly move downstream, and a stable stream and revegetated floodplain to form upstream. Notching, in this study of a dam on Brewster...
Simulation of an urban ground-water-flow system in the Menomonee Valley, Milwaukee, Wisconsin using analytic element modeling
C. P. Dunning, D. T. Feinstein
2004, Conference Paper, Bridging the Gap: Meeting the World's Water and Environmental Resources Challenges - Proceedings of the World Water and Environmental Resources Congress 2001
A single-layer, steady-state analytic element model was constructed to simulate shallow ground-water flow in the Menomonee Valley, an old industrial center southwest of downtown Milwaukee, Wisconsin. Project objectives were to develop an understanding of the shallow ground-water flow system and identify primary receptors of recharge to the valley. The analytic...
Strontium isotopic signatures of oil-field waters: Applications for reservoir characterization
R.J. Barnaby, G.C. Oetting, G. Gao
2004, American Association of Petroleum Geologists Bulletin (88) 1677-1704
The 87Sr/86Sr compositions of formation waters that were collected from 71 wells producing from a Pennsylvanian carbonate reservoir in New Mexico display a well-defined distribution, with radiogenic waters (up to 0.710129) at the updip western part of the reservoir, grading downdip to less radiogenic waters (as low as 0.708903 to...
Evidence for increased latent heat transport during the Cretaceous (Albian) greenhouse warming
David F. Ufnar, Luis A. Gonzalez, Greg A. Ludvigson, Richard L. Brenner, B.J. Witzke
2004, Geology (32) 1049-1052
Quantitative estimates of increased heat transfer by atmospheric H 2O vapor during the Albian greenhouse warming suggest that the intensified hydrologic cycle played a greater role in warming high latitudes than at present and thus represents a viable alternative to oceanic heat transport. Sphaerosiderite ??18O values in paleosols of the...
Hydraulic tests in highly permeable aquifers
James J. Butler Jr., Xiaoyong Zhan
2004, Water Resources Research (40)
A semianalytical solution is presented for a mathematical model describing the flow of groundwater in response to a slug or pumping test in a highly permeable, confined aquifer. This solution, which is appropriate for wells of any degree of penetration and incorporates inertial mechanisms at both the test and observation...
Methods and guidelines for effective model calibration
M. C. Hill
2004, Conference Paper, Joint Conference on Water Resource Engineering and Water Resources Planning and Management 2000: Building Partnerships
This paper briefly describes nonlinear regression methods, a set of 14 guidelines for model calibration, how they are implemented in and supported by two public domain computer programs, and a demonstration and a test of the methods and guidelines. Copyright ASCE 2004....
A web-enabled system for integrated assessment of watershed development
R. Dymond, V. Lohani, B. Regmi, R. Dietz
2004, Conference Paper, Bridging the Gap: Meeting the World's Water and Environmental Resources Challenges - Proceedings of the World Water and Environmental Resources Congress 2001
Researchers at Virginia Tech have put together the primary structure of a web enabled integrated modeling system that has potential to be a planning tool to help decision makers and stakeholders in making appropriate watershed management decisions. This paper describes the integrated system, including data sources, collection, analysis methods, system...
Spatial and temporal variation of Cenozoic surface elevation in the Great Basin and Sierra Nevada
T.W. Horton, D.J. Sjostrom, M.J. Abruzzese, M.A. Poage, J.R. Waldbauer, M. Hren, J. Wooden, C. P. Chamberlain
2004, American Journal of Science (304) 862-888
The surface uplift of mountain belts caused by tectonism plays an important role in determining the long-term climate evolution of the Earth. However, the general lack of information on the paleotopography of mountain belts limits our ability to identify the links and feedbacks between topography, tectonics, and climate change on...
Standard penetration test-based probabilistic and deterministic assessment of seismic soil liquefaction potential
K.O. Cetin, R.B. Seed, A. Der Kiureghian, K. Tokimatsu, L.F. Harder Jr., R. E. Kayen, R.E.S. Moss
2004, Journal of Geotechnical and Geoenvironmental Engineering (130) 1314-1340
This paper presents'new correlations for assessment of the likelihood of initiation (or triggering) of soil liquefaction. These new correlations eliminate several sources of bias intrinsic to previous, similar correlations, and provide greatly reduced overall uncertainty and variance. Key elements in the development of these new correlations are (1) accumulation of...
Beliefs and attitudes toward lethal management of deer in Cuyahoga Valley National Park
D.C. Fulton, K. Skerl, E.M. Shank, D.W. Lime
2004, Conference Paper, Wildlife Society Bulletin
We used the theory of reasoned action to help understand attitudes and beliefs about lethal management of deer (Odocoileus virginianus) in Cuyahoga Valley National Park (CVNP), Ohio. We used a mail-back survey to collect data from Ohio residents in the surrounding 9-county area. Two strata were defined: residents <10 km...
Use of acoustic technology to define hydraulic characteristics of an estuary near the Mississippi Gulf Coast
K. Van Wilson Jr.
2004, Conference Paper, Joint Conference on Water Resource Engineering and Water Resources Planning and Management 2000: Building Partnerships
An Acoustic Doppler Current Profiler (ADCP) was used on the Jourdan River at Interstate Highway 10 near Kiln, Mississippi, in 1996 to measure three-dimensional velocity vectors and water depths and in 1998, in combination with a global positioning system, to define channel bathymetry in the vicinity of the bridge. During...
Rupture process of the M 7.9 Denali fault, Alaska, earthquake: Subevents, directivity, and scaling of high-frequency ground motions
A. Frankel
2004, Bulletin of the Seismological Society of America (94) S234-S255
Displacement waveforms and high-frequency acceleration envelopes from stations at distances of 3-300 km were inverted to determine the source process of the M 7.9 Denali fault earthquake. Fitting the initial portion of the displacement waveforms indicates that the earthquake started with an oblique thrust subevent (subevent # 1) with an...
Tailrace Egress of yearling and subyearling Chinook salmon and juvenile steelhead following juvenile bypass system passage at John Day Dam, 2002
C. D. Smith, Theresa L. Liedtke, B.J. Hausmann, Jacquelyn L. Schei, J.R. Lyng, L.P. Gee, John W. Beeman
2004, Report
No abstract available....
Effects of an insecticide on amphibians in large-scale experimental ponds
M.D. Boone, R. D. Semlitsch, J.F. Fairchild, B.B. Rothermel
2004, Ecological Applications (14) 685-691
We examined the effects of the insecticide carbaryl on larval amphibian communities in large-scale experimental ponds. Tadpoles of two anurans, Woodhouse's toad (Bufo woodhousii) and southern leopard Frog (Rana sphenocephala), were reared in ponds (800 m3 volume) to determine the effects of tadpole density and carbaryl exposure on mass at...
Two-threshold model for scaling laws of noninteracting snow avalanches
J. Faillettaz, F. Louchet, J.-R. Grasso
2004, Physical Review Letters (93)
A two-threshold model was proposed for scaling laws of noninteracting snow avalanches. It was found that the sizes of the largest avalanches just preceding the lattice system were power-law distributed. The proposed model reproduced the range of power-law exponents observe for land, rock or snow avalanches, by tuning the maximum...
Agricultural ponds support amphibian populations
M. G. Knutson, W. B. Richardson, D.M. Reineke, B. R. Gray, J.R. Parmelee, S.E. Weick
2004, Ecological Applications (14) 669-684
In some agricultural regions, natural wetlands are scarce, and constructed agricultural ponds may represent important alternative breeding habitats for amphibians. Properly managed, these agricultural ponds may effectively increase the total amount of breeding habitat and help to sustain populations. We studied small, constructed agricultural ponds in southeastern Minnesota to assess...
Density and habitat associations of Barred Owls at the edge of their range in Oklahoma
Brian R. Winton, David M. Leslie Jr.
2004, Southeastern Naturalist (3) 475-482
We assessed breeding-pair density and habitat associations of Barred Owls (Strix varia) at the edge of their range in north-central Oklahoma in 1995-1996. We played taped calls of Barred Owls to solicit and record responses (visual and auditory) and thereby determine density in our 1155-ha study area. Numbers of owls...
An exact solution for effects of topography on free Rayleigh waves
W. Z. Savage
2004, Bulletin of the Seismological Society of America (94) 1706-1727
An exact solution for the effects of topography on Rayleigh wave amplification is presented. The solution is obtained by incorporating conformal mapping into complex-variable stress functions developed for free Rayleigh wave propagation in an elastic half-space with a flat upper surface. Results are presented for free Rayleigh wave propagation across...
Evaluation of nekton use and habitat characteristics of restored Louisiana marsh
C.S.B. Thom, M.K.G.L. Peyre, J.A. Nyman
2004, Ecological Engineering (23) 63-75
Marsh terracing and coconut fiber mats are two wetland restoration techniques implemented at Sabine National Wildlife Refuge, Louisiana, USA. Using nekton as an indicator of habitat quality, nekton community assemblages were compared between terraced, coconut-matted, unmanaged marsh (restoration goal), and open water (pre-restoration) habitats. Using a throw trap and a...
Prevalence of the parasitic copepod Haemobaphes intermedius on juvenile buffalo sculpins from Washington State
C.M. Halpenny, R. M. Kocan, P.K. Hershberger
2004, Journal of Aquatic Animal Health (16) 161-163
The parasitic copepod, Haemobaphes intermedius, was detected in 62% of juvenile buffalo sculpins Enophrys bison, a previously unreported host, from the San Juan Islands archipelago in Washington State. Most infestations were characterized by the presence of a single female copepod infestations with multiple H. intermedius occurred either unilaterally or bilaterally...
