Oxygen isotopes in nitrate: New reference materials for 18O:17O:16O measurements and observations on nitrate-water equilibration
J.K. Böhlke, S.J. Mroczkowski, T.B. Coplen
2003, Rapid Communications in Mass Spectrometry (17) 1835-1846
Despite a rapidly growing literature on analytical methods and field applications of O isotope-ratio measurements of NO3− in environmental studies, there is evidence that the reported data may not be comparable because reference materials with widely varying δ18O values have not been readily available. To address this problem, we prepared...
Stratigraphy and palaeoclimatic significance of Late Quaternary loess-palaeosol sequences of the Last Interglacial-Glacial cycle in central Alaska
D.R. Muhs, T. A. Ager, E. Arthur Bettis III, J. McGeehin, J.M. Been, J. E. Beget, M.J. Pavich, Thomas W. Stafford Jr., D.A.S.P. Stevens
2003, Quaternary Science Reviews (22) 1947-1986
Loess is one of the most widespread subaerial deposits in Alaska and adjacent Yukon Territory and may have a history that goes back 3 Ma. Based on mineralogy and major and trace element chemistry, central Alaskan loess has a composition that is distinctive from other loess bodies of the world,...
Evaluation of specific ultraviolet absorbance as an indicator of the chemical composition and reactivity of dissolved organic carbon
J.L. Weishaar, George R. Aiken, Brian A. Bergamaschi, Miranda S. Fram, Roger Fujii, K. Mopper
2003, Environmental Science & Technology (37) 4702-4708
Specific UV absorbance (SUVA) is defined as the UV absorbance of a water sample at a given wavelength normalized for dissolved organic carbon (DOC) concentration. Our data indicate that SUVA, determined at 254 nm, is strongly correlated with percent aromaticity as determined by 13C NMR for 13 organic matter isolates...
Atmospheric microbiology in the northern Caribbean during African dust events
Dale W. Griffin, C.A. Kellogg, V.H. Garrison, J.T. Lisle, T.C. Borden, E.A. Shinn
2003, Aerobiologia (19) 143-157
Between July 2000 and August 2001 forty-three air samples were collected in the northern Caribbean: Twenty-six in the US Virgin Islands, and 17 samples aboard ship during two 1-week cruises. Samples were collected during African dust events and non-dust conditions and screened for the presence of culturable bacteria and fungi....
Variation in trophic shift for stable isotope ratios of carbon, nitrogen, and sulfur
J.H. McCutchan Jr., W.M. Lewis Jr., C. Kendall, C.C. McGrath
2003, Oikos (102) 378-390
Use of stable isotope ratios to trace pathways of organic matter among consumers requires knowledge of the isotopic shift between diet and consumer. Variation in trophic shift among consumers can be substantial. For data from the published literature and supplementary original data (excluding fluid-feeding consumers), the mean isotopic shift for...
Detailed fault structure of the 2000 Western Tottori, Japan, earthquake sequence
E. Fukuyama, W.L. Ellsworth, F. Waldhauser, A. Kubo
2003, Bulletin of the Seismological Society of America (93) 1468-1478
We investigate the faulting process of the aftershock region of the 2000 western Tottori earthquake (Mw 6.6) by combining aftershock hypocenters and moment tensor solutions. Aftershock locations were precisely determined by the double difference method using P- and S-phase arrival data of the Japan Meteorological Agency unified catalog. By combining...
Use of radar remote sensing (RADARSAT) to map winter wetland habitat for shorebirds in an agricultural landscape
O.W. Taft, S. M. Haig, Chris Kiilsgaard
2003, Environmental Management (32) 268-281
Many of today's agricultural landscapes once held vast amounts of wetland habitat for waterbirds and other wildlife. Successful restoration of these landscapes relies on access to accurate maps of the wetlands that remain. We used C-band (5.6-cm-wavelength), HH-polarized radar remote sensing (RADARSAT) at a 38?? incidence angle (8-m resolution) to...
A triangular model of dimensionless runoff producing rainfall hyetographs in Texas
W.H. Asquith, J.R. Bumgarner, L.S. Fahlquist
2003, Journal of the American Water Resources Association (39) 911-921
A synthetic triangular hyetograph for a large data base of Texas rainfall and runoff is needed. A hyetograph represents the temporal distribution of rainfall intensity at a point or over a watershed during a storm. Synthetic hyetographs are estimates of the expected time distribution for a design storm and principally...
Photographic techniques for characterizing streambed particle sizes
Matthew S. Whitman, Edward H. Moran, Robert T. Ourso
2003, Transactions of the American Fisheries Society (132) 605-610
We developed photographic techniques to characterize coarse (>2-mm) and fine (≤2-mm) streambed particle sizes in 12 streams in Anchorage, Alaska. Results were compared with current sampling techniques to assess which provided greater sampling efficiency and accuracy. The streams sampled were wadeable and contained gravel—cobble streambeds. Gradients ranged from about 5%...
Multichannel analysis of surface wave method with the autojuggie
G. Tian, D.W. Steeples, J. Xia, R. D. Miller, K.T. Spikes, M.D. Ralston
2003, Soil Dynamics and Earthquake Engineering (23) 243-247
The shear (S)-wave velocity of near-surface materials and its effect on seismic-wave propagation are of fundamental interest in many engineering, environmental, and groundwater studies. The multichannel analysis of surface wave (MASW) method provides a robust, efficient, and accurate tool to observe near-surface S-wave velocity. A recently developed device used to...
Development of hardwood seed zones for Tennessee using a geographic information system
L.S. Post, S.E. Schlarbaum, F. Van Manen, R.A. Cecich, A.M. Saxton, J.F. Schneider
2003, Southern Journal of Applied Forestry (27) 172-175
For species that have no or limited information on genetic variation and adaptability to nonnative sites, there is a need for seed collection guidelines based on biological, climatological, and/or geographical criteria. Twenty-eight hardwood species are currently grown for reforestation purposes at the East Tennessee State Nursery. The majority of these...
Direct numerical simulation of bedload transport using a local, dynamic boundary condition
M.W. Schmeeckle, J. M. Nelson
2003, Sedimentology (50) 279-301
Temporally and spatially averaged models of bedload transport are inadequate to describe the highly variable nature of particle motion at low transport stages. The primary sources of this variability are the resisting forces to downstream motion resulting from the geometrical relation (pocket friction angle) of a bed grain to the...
Shallow-velocity models at the Kilauea Volcano, Hawaii, determined from array analyses of tremor wavefields
G. Saccorotti, B. Chouet, P. Dawson
2003, Geophysical Journal International (152) 633-648
The properties of the surface wavefield at Kilauea Volcano are analysed using data from small-aperture arrays of short-period seismometers deployed in and around the Kilauea caldera. Tremor recordings were obtained during two Japan-US cooperative experiments conducted in 1996 and 1997. The seismometers were deployed in three semi-circular arrays with apertures...
Entropy and generalized least square methods in assessment of the regional value of streamgages
M. Markus, Knapp H. Vernon, Gary D. Tasker
2003, Journal of Hydrology (283) 107-121
The Illinois State Water Survey performed a study to assess the streamgaging network in the State of Illinois. One of the important aspects of the study was to assess the regional value of each station through an assessment of the information transfer among gaging records for low, average, and high...
Lower survival probabilities for adult Florida manatees in years with intense coastal storms
C.A. Langtimm, C.A. Beck
2003, Ecological Applications (13) 257-268
The endangered Florida manatee (Trichechus manatus latirostris) inhabits the subtropical waters of the southeastern United States, where hurricanes are a regular occurrence. Using mark-resighting statistical models, we analyzed 19 years of photo-identification data and detected significant annual variation in adult survival for a subpopulation in northwest Florida where human impact...
Quantitative analysis of seismic fault zone waves in the rupture zone of the 1992 Landers, California, earthquake: Evidence for a shallow trapping structure
Z. Peng, Y. Ben-Zion, A.J. Michael, L. Zhu
2003, Geophysical Journal International (155) 1021-1041
We analyse quantitatively a waveform data set of 238 earthquakes recorded by a dense seismic array across and along the rupture zone of the 1992 Landers earthquake. A grid-search method with station delay corrections is used to locate events that do not have catalogue locations. The quality of fault zone...
An index of biological integrity (IBI) for Pacific Northwest rivers
C.A. Mebane, T.R. Maret, R. M. Hughes
2003, Transactions of the American Fisheries Society (132) 239-261
The index of biotic integrity (IBI) is a commonly used measure of relative aquatic ecosystem condition; however, its application to coldwater rivers over large geographic areas has been limited. A seven-step process was used to construct and test an IBI applicable to fish assemblages in coldwater rivers throughout the U.S....
Effects of brevetoxins on murine myeloma SP2/O cells: Aberrant cellular division
T.K. Han, M. Derby, D.F. Martin, S.D. Wright, M.L. Dao
2003, International Journal of Toxicology (22) 73-80
Massive deaths of manatees (Trichechus manatus latirostris) during the red tide seasons have been attributed to brevetoxins produced by the dinoflagellate Karenia brevis (formerly Ptychodiscus breve and Gymnodinium breve). Although these toxins have been found in macrophages and lymphocytes in the lung, liver, and secondary lymphoid tissues of these animals,...
Variance in prey abundance influences time budgets of breeding seabirds: Evidence from pigeon guillemots Cepphus columba
Michael A. Litzow, John F. Piatt
2003, Journal of Avian Biology (34) 54-64
We use data on pigeon guillemots Cepphus columba to test the hypothesis that discretionary time in breeding seabirds is correlated with variance in prey abundance. We measured the amount of time that guillemots spent at the colony before delivering fish to chicks ("resting time") in relation to fish abundance as...
Environmental fate and effects of the lampricide TFM: A review
T.D. Hubert
2003, Conference Paper, Journal of Great Lakes Research
Use of 3-trifluoromethyl-4-nitrophenol (TFM) is limited geographically to the Great Lakes basin where it is the principal agent used in control of the sea lamprey (Petromyzon marinus). It is clear from available data that TFM has effects on the environment, but the effects reported are transient. Individual organisms and aquatic...
Lithogeochemistry of Carlin-type gold mineralization in the Gold Bar district, Battle Mountain-Eureka trend, Nevada
O. Yigit, A. H. Hofstra
2003, Ore Geology Reviews (22) 201-224
The Gold Bar district contains five Carlin-type gold deposits and four resources for a combined gold endowment of 1.6 M oz [50 t]. The gold deposits are hosted in Devonian carbonate rocks below parautochthonous and allochthonous Paleozoic siliciclastic rocks emplaced during the Early Mississippian Antler orogeny. The district is in...
Geology of the MER 2003 "Elysium" candidate landing site in southeastern Utopia Planitia, Mars
Kenneth L. Tanaka, Michael H. Carr, James A. Skinner, Martha S. Gilmore, Trent M. Hare
2003, Journal of Geophysical Research E: Planets (108)
The NASA Mars Exploration Rover (MER) Project has been considering a landing-site ellipse designated EP78B2 in southeastern Utopia Planitia, southwest of Elysium Mons. The site appears to be relatively safe for a MER landing site because of its predicted low wind velocities in mesoscale atmospheric circulation models and its low...
Importance of geology to fisheries management: Examples from the northeastern Gulf of Mexico
Kathryn M. Scanlon, Christopher C. Koenig, Felicia C. Coleman, Margaret W. Miller
2003, American Fisheries Society Symposium (2003) 95-99
Seafloor mapping of shelf-edge habitats in the northeastern Gulf of Mexico demonstrates how sidescan-sonar imagery, seismic-reflection profiling, video data, geologic mapping, sediment sampling, and understanding the regional geologic history can enhance, support, and guide traditional fisheries research and management. New data from the Madison Swanson and Steamboat Lumps Marine Reserves...
Crystallisation ages in coeval silicic magma bodies: 238U-230Th disequilibrium evidence from the Rotoiti and earthquake flat eruption deposits, Taupo volcanic zone, New Zealand
B. L. A. Charlier, D.W. Peate, C. J. N. Wilson, J. B. Lowenstern, M. Storey, S.J.A. Brown
2003, Earth and Planetary Science Letters (206) 441-457
The timescales over which moderate to large bodies of silicic magma are generated and stored are addressed here by studies of two geographically adjacent, successive eruption deposits in the Taupo Volcanic Zone, New Zealand. The earlier, caldera-forming Rotoiti eruption (>100 km3 magma) at Okataina volcano was followed, within months at...
High-resolution topomapping of candidate MER landing sites with Mars Orbiter Camera narrow-angle images
Randolph L. Kirk, Elpitha Howington-Kraus, Bonnie L. Redding, Donna M. Galuszka, Trent M. Hare, Brent A. Archinal, Laurence A. Soderblom, Janet M. Barrett
2003, Journal of Geophysical Research E: Planets (108)
We analyzed narrow‐angle Mars Orbiter Camera (MOC‐NA) images to produce high‐resolution digital elevation models (DEMs) in order to provide topographic and slope information needed to assess the safety of candidate landing sites for the Mars Exploration Rovers (MER) and to assess the accuracy of our results by a variety of...
