Application of ground-penetrating radar imagery for three-dimensional visualisation of near-surface structures in ice-rich permafrost, Barrow, Alaska
Jeffrey S. Munroe, James A. Doolittle, Mikhail Kanevskiy, Kenneth M. Hinkel, Frederick E. Nelson, Benjamin M. Jones, Yuri Shur, John M. Kimble
2007, Permafrost and Periglacial Processes (18) 309-321
Three-dimensional ground-penetrating radar (3D GPR) was used to investigate the subsurface structure of ice-wedge polygons and other features of the frozen active layer and near-surface permafrost near Barrow, Alaska. Surveys were conducted at three sites located on landscapes of different geomorphic age. At each site, sediment cores were collected and...
Reconstructing late Cenozoic stream gradients from high-level chert gravels in central Eastern Kansas
J.W. Harbaugh, D. F. Merriam, H.H. Howard
2007, Current Research in Earth Sciences (253)
Interpreting the evolution of Kansas' landscape east of the Flint Hills provides major challenges. In the Neogene (late Tertiary) and perhaps part of the Pleistocene, streams transported a variety of sedimentary materials, including chert gravels derived from the Flint Hills. Gentle intermittent uplift stimulated the system system to cut down,...
Basin structure beneath the Santa Rosa Plain, Northern California: Implications for damage caused by the 1969 Santa Rosa and 1906 San Francisco earthquakes
D.K. McPhee, V.E. Langenheim, S. Hartzell, R. J. McLaughlin, Brad T. Aagaard, R.C. Jachens, C. McCabe
2007, Bulletin of the Seismological Society of America (97) 1449-1457
Regional gravity data in the northern San Francisco Bay region reflect a complex basin configuration beneath the Santa Rosa plain that likely contributed to the significant damage to the city of Santa Rosa caused by the 1969 M 5.6, 5.7 Santa Rosa earthquakes and the...
Paleomagnetic and mineral magnetic constraints on Zn-Pb ore genesis in the Pend Oreille Mine, Metaline district, Washington, USA
S.J. Pannalal, David T. A. Symons, D. L. Leach
2007, Canadian Journal of Earth Sciences (44) 1661-1673
Zinc-lead mineralization in the Metaline mining district of northeastern Washington, USA, is hosted by the Cambrian Metaline Formation and is classified into Yellowhead-type (YO) and Josephine-type (JO) ore based on texture and mineralogy. Paleomagnetic results are reported for four Cambrian Metaline Formation sites, one Ordovician Ledbetter slate site, 12 YO...
Prime candidate earth targets for the post-launch radiometric calibration of space-based optical imaging instruments
P.M. Teillet, J. A. Barsi, G. Chander, K. J. Thome
2007, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
This paper provides a comprehensive list of prime candidate terrestrial targets for consideration as benchmark sites for the post-launch radiometric calibration of space-based instruments. The key characteristics of suitable sites are outlined primarily with respect to selection criteria, spatial uniformity, and temporal stability. The establishment and utilization of such benchmark...
Predicting wetland plant community responses to proposed water-level-regulation plans for Lake Ontario: GIS-based modeling
D.A. Wilcox, Y. Xie
2007, Journal of Great Lakes Research (33) 751-773
Integrated, GIS-based, wetland predictive models were constructed to assist in predicting the responses of wetland plant communities to proposed new water-level regulation plans for Lake Ontario. The modeling exercise consisted of four major components: 1) building individual site wetland geometric models; 2) constructing generalized wetland geometric models representing specific types...
Estimating trend precision and power to detect trends across grouped count data
B. R. Gray, M.M. Burlew
2007, Ecology (88) 2364-2372
Ecologists commonly use grouped or clustered count data to estimate temporal trends in counts, abundance indices, or abundance. For example, the U.S. Breeding Bird Survey data represent multiple counts of birds from within each of multiple, spatially defined routes. Despite a reliance on grouped counts, analytical methods for prospectively estimating...
Highstand fans in the California borderland: The overlooked deep-water depositional systems
Jacob A. Covault, William R. Normark, Brian W. Romans, Stephan A. Graham
2007, Geology (35) 783-786
Contrary to widely used sequence-stratigraphic models, lowstand fans are only part of the turbidite depositional record; our analysis reveals that a comparable volume of coarse-grained sediment has been deposited in California borderland deep-water basins regardless of sea level. Sedimentation rates and periods of...
Sexual selection in the squirrel treefrog Hyla squirella: the role of multimodal cue assessment in female choice
Ryan C. Taylor, Bryant W. Buchanan, Jessie L. Doherty
2007, Animal Behaviour (74) 1753-1763
Anuran amphibians have provided an excellent system for the study of animal communication and sexual selection. Studies of female mate choice in anurans, however, have focused almost exclusively on the role of auditory signals. In this study, we examined the effect of both auditory and visual cues on female choice...
Faunal re-evaluation of Mid-Pliocene conditions in the western equatorial Pacific
H. Dowsett
2007, Micropaleontology (53) 447-456
Mid-Pliocene low-latitude Pacific faunal (planktic foraminifer) sea surface temperature (SST) estimates are normally based upon the Modern Analog Technique (MAT). In the Eastern equatorial Pacific (EEP), where upwelling of cool water predominates, MAT can be used to discern both cooling and warming in Neogene records. SST today is ???30??C in...
Distinguishing wild vs. stocked lake trout (Salvelinus namaycush) in Lake Ontario: Evidence from carbon and oxygen stable isotope values of otoliths
T. Schaner, W.P. Patterson, B.F. Lantry, R. O'Gorman
2007, Journal of Great Lakes Research (33) 912-916
We investigated the potential for using carbon and oxygen isotope values of otolith carbonate as a method to distinguish naturally produced (wild) lake trout (Salvelinus namaycush) from hatchery-reared lake trout in Lake Ontario. We determined δ 13C(CaCO3) and δ 18O(CaCO3) values of otoliths from juvenile fish taken from two hatcheries, and of otoliths from...
Evaluation of a small beach nourishment project to enhance habitat suitability for horseshoe crabs
N.L. Jackson, D. R. Smith, R. Tiyarattanachai, K.F. Nordstrom
2007, Geomorphology (89) 172-185
This field study evaluates the effect of nourishing an estuarine beach with gravel to enhance spawning rates by horseshoe crabs. A total of 564??m3 of coarse sand and gravel were emplaced in two 90??m-long treatment segments at Bowers Beach, Delaware, USA from 9 to 11 April 2002. Field data were...
Home ranges and habitat use of sloth bears Melursus ursinus inornatus in Wasgomuwa National Park, Sri Lanka
S. Ratnayeke, F.T. Van Manen, U.K.G.K. Padmalal
2007, Wildlife Biology (13) 272-284
We studied home ranges and habitat selection of 10 adult sloth bears Melursus ursinus inornatus at Wasgomuwa National Park, Sri Lanka during 2002-2003. Very little is known about the ecology and behaviour of M. u. inornatus, which is a subspecies found in Sri Lanka. Our study was undertaken to assess...
Homogeneity of the geochemical reference material BRP-1 (paraná basin basalt) and assessment of minimum mass
Aloisio J. B. Cotta, Jacinta Enzweiler, Stephen A. Wilson, Carlos A. Perez, Antonio J. R. Nardy, Joao H. Larizzatti
2007, Geostandards and Geoanalytical Research (31) 379-393
Reference materials (RM) are required for quantitative analyses and their successful use is associated with the degree of homogeneity, and the traceability and confidence limits of the values established by characterisation. During the production of a RM, the chemical characterisation can only commence after it has been demonstrated that the...
Monitoring and modeling ice-rock avalanches from ice-capped volcanoes: A case study of frequent large avalanches on Iliamna Volcano, Alaska
C. Huggel, J. Caplan-Auerbach, C. F. Waythomas, R.L. Wessels
2007, Journal of Volcanology and Geothermal Research (168) 114-136
Iliamna is an andesitic stratovolcano of the Aleutian arc with regular gas and steam emissions and mantled by several large glaciers. Iliamna Volcano exhibits an unusual combination of frequent and large ice-rock avalanches in the order of 1 ?? 106??m3 to 3 ?? 107??m3 with recent return periods of 2-4??years....
Lethal and sublethal effects of ammonia to juvenile Lampsilis mussels (Unionidae) in sediment and water-only exposures
T.J. Newton, M.R. Bartsch
2007, Environmental Toxicology and Chemistry (26) 2057-2065
We compared the sensitivity of two juvenile unionid mussels (Lampsilis cardium and Lampsilis higginsii) to ammonia in 96-h water-only and sediment tests by use of mortality and growth measurements. Twenty mussels were placed in chambers buried 2.5 cm into reference sediments to approximate pore-water exposure (sediment tests) or elevated above...
Stability and uncertainty of finite-fault slip inversions: Application to the 2004 Parkfield, California, earthquake
S. Hartzell, P. Liu, C. Mendoza, C. Ji, K.M. Larson
2007, Bulletin of the Seismological Society of America (97) 1911-1934
The 2004 Parkfield, California, earthquake is used to investigate stability and uncertainty aspects of the finite-fault slip inversion problem with different a priori model assumptions. We utilize records from 54 strong ground motion stations and 13 continuous, 1-Hz sampled, geodetic instruments. Two inversion procedures are compared: a linear least-squares subfault-based...
Consequences of land-cover misclassification in models of impervious surface
Gerard McMahon
2007, Photogrammetric Engineering and Remote Sensing (73) 1343-1353
Model estimates of impervious area as a function of landcover area may be biased and imprecise because of errors in the land-cover classification. This investigation of the effects of land-cover misclassification on impervious surface models that use National Land Cover Data (NLCD) evaluates the consequences of adjusting land-cover within a...
Evaluation of sulfate reduction at experimentally induced mixing interfaces using small-scale push-pull tests in an aquifer-wetland system
T.A. Kneeshaw, Jennifer T. McGuire, Erik W. Smith, Isabelle M. Cozzarelli
2007, Applied Geochemistry (22) 2618-2629
This paper presents small-scale push–pull tests designed to evaluate the kinetic controls on SO42-">SO42- reduction in situ at mixing interfaces between a wetland and aquifer impacted by landfill leachate at the Norman Landfill research site, Norman, OK. Quantifying the...
Investigation of the groundwater system at Masaya Caldera, Nicaragua, using transient electromagnetics and numerical simulation
R.E. MacNeil, W. E. Sanford, C.B. Connor, S.K. Sandberg, M. Diez
2007, Journal of Volcanology and Geothermal Research (166) 217-232
The distribution of groundwater beneath Masaya Volcano, in Nicaragua, and its surrounding caldera was characterized using the transient electromagnetic method (TEM). Multiple soundings were conducted at 30 sites. Models of the TEM data consistently indicate a resistive layer that is underlain by one or more conductive layers. These two layers...
Postearthquake relaxation and aftershock accumulation linearly related after the 2003 M 6.5 Chengkung, Taiwan, and the 2004 M 6.0 Parkfield, California, earthquakes
J.C. Savage, S.-B. Yu
2007, Bulletin of the Seismological Society of America (97) 1632-1645
We treat both the number of earthquakes and the deformation following a mainshock as the superposition of a steady background accumulation and the postearthquake process. The preseismic displacement and seismicity rates ru and rE are used as estimates of the background rates. Let t be the time after the...
Investigation of magnesium isotope fractionation during basalt differentiation: Implications for a chondritic composition of the terrestrial mantle
F.-Z. Teng, M. Wadhwa, Rosalind T. Helz
2007, Earth and Planetary Science Letters (261) 84-92
To investigate whether magnesium isotopes are fractionated during basalt differentiation, we have performed high-precision Mg isotopic analyses by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) on a set of well-characterized samples from Kilauea Iki lava lake, Hawaii, USA. Samples from the Kilauea Iki...
Summer microhabitat use of fluvial bull trout in Eastern Oregon streams
R. Al-Chokhachy, P. Budy
2007, North American Journal of Fisheries Management (27) 1068-1081
The management and recovery of populations of bull trout Salvelinus confluentus requires a comprehensive understanding of habitat use across different systems, life stages, and life history forms. To address these needs, we collected microhabitat use and availability data in three fluvial populations of bull trout in eastern Oregon. We evaluated...
Physically based estimation of soil water retention from textural data: General framework, new models, and streamlined existing models
John R. Nimmo, William N. Herkelrath, Luna Laguna
2007, Vadose Zone Journal (6) 766-773
Numerous models are in widespread use for the estimation of soil water retention from more easily measured textural data. Improved models are needed for better prediction and wider applicability. We developed a basic framework from which new and existing models can be derived to facilitate improvements. Starting from the assumption...
In situ time-series measurements of subseafloor sediment properties
R. A. Wheatcroft, A.W. Stevens, R.V. Johnson
2007, IEEE Journal of Oceanic Engineering (32) 862-871
The capabilities and diversity of subsurface sediment sensors lags significantly from what is available for the water column, thereby limiting progress in understanding time-dependent seabed exchange and high-frequency acoustics. To help redress this imbalance, a new instrument, the autonomous sediment profiler (ASP), is described herein....
