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...
Ecosystem N distribution and δ15N during a century of forest regrowth after agricultural abandonment
J.E. Compton, T.D. Hooker, S.S. Perakis
2007, Ecosystems (10) 1197-1208
Stable isotope ratios of terrestrial ecosystem nitrogen (N) pools reflect internal processes and input–output balances. Disturbance generally increases N cycling and loss, yet few studies have examined ecosystem δ15N over a disturbance-recovery sequence. We used a chronosequence approach to examine N distribution and δ15N during forest regrowth after agricultural abandonment....
Long-term limnological research and monitoring at Crater Lake, Oregon
G.L. Larson, R. Collier, M. Buktenica
2007, Hydrobiologia (574) 1-11
Crater Lake is located in the caldera of Mount Mazama in Crater Lake National Park, Oregon. The lake has a surface area of about 53 km2at an elevation of 1882 m and a maximum depth of 594 m. Limited studies of this ultraoligotrophic lake conducted between 1896 and 1981, lead...
CO2 storage capacity estimation: Issues and development of standards
J. Bradshaw, S. Bachu, D. Bonijoly, R. Burruss, S. Holloway, N.P. Christensen, O.M. Mathiassen
2007, International Journal of Greenhouse Gas Control (1) 62-68
Associated with the endeavours of geoscientists to pursue the promise that geological storage of CO2 has of potentially making deep cuts into greenhouse gas emissions, Governments around the world are dependent on reliable estimates of CO2 storage capacity and insightful indications of the viability of geological storage in their respective...
Coupled changes in sand grain size and sand transport driven by changes in the upstream supply of sand in the Colorado River: relative importance of changes in bed-sand grain size and bed-sand area
D.J. Topping, D. M. Rubin, T.S. Melis
2007, Sedimentary Geology (202) 538-561
Sand transport in the Colorado River in Marble and Grand canyons was naturally limited by the upstream supply of sand. Prior to the 1963 closure of Glen Canyon Dam, the river exhibited the following four effects of sand supply limitation: (1) hysteresis in sediment concentration, (2) hysteresis in sediment grain...
Geographic variation in avian incubation periods and parental influences on embryonic temperature
T. E. Martin, S.K. Auer, R.D. Bassar, Alina M. Niklison, P. Lloyd
2007, Evolution (61) 2558-2569
Theory predicts shorter embryonic periods in species with greater embryo mortality risk and smaller body size. Field studies of 80 passerine species on three continents yielded data that largely conflicted with theory; incubation (embryonic) periods were longer rather than shorter in smaller species, and egg (embryo) mortality risk explained some...
Why the sacramento delta area differs from other parts of the great valley: numerical modeling of thermal structure and thermal subsidence of forearc basins
V.O. Mikhailov, T. Parsons, R.W. Simpson, E.P. Timoshkina, C. Williams
2007, Izvestiya, Physics of the Solid Earth (43) 75-90
Data on present-day heat flow, subsidence history, and paleotemperature for the Sacramento Delta region, California, have been employed to constrain a numerical model of tectonic subsidence and thermal evolution of forearc basins. The model assumes an oceanic basement with an initial thermal profile dependent on its age subjected to refrigeration...
Palynological correlation of Atokan and lower desmoinesian (Pennsylvanian) strata between the Illinois basin and the Forest City basin in Eastern Kansas
R.A. Peppers, L. L. Brady
2007, Current Research in Earth Sciences (253)
Palynological correlation is made between Atokan and lower Desmoinesian strata in the Illinois basin an the Forest City basin in eastern Kansas. Spore data from previous studies of coals in the Illinois basin and other coal basins are compared with data from spore assemblages in coal and carbonaceous shale bands...
Late Quaternary stratigraphy and luminescence geochronology of the northeastern Mojave Desert
S. A. Mahan, D. M. Miller, C.M. Menges, J. C. Yount
2007, Quaternary International (166) 61-78
The chronology of the Holocene and late Pleistocene deposits of the northeastern Mojave Desert have been largely obtained using radiocarbon ages. Our study refines and extends this framework using optically stimulated luminescence (OSL) to date deposits from Valjean Valley, Silurian Lake Playa, Red Pass, and California Valley. Of particular interest...
Breeding ponds colonized by striped newts after 10 or more years
C.K. Dodd Jr., S. A. Johnson
2007, Herpetological Review (38) 150-152
[No abstract available]...
CO2 storage capacity estimation: Methodology and gaps
S. Bachu, D. Bonijoly, J. Bradshaw, R. Burruss, S. Holloway, N.P. Christensen, O.M. Mathiassen
2007, International Journal of Greenhouse Gas Control (1) 430-443
Implementation of CO2 capture and geological storage (CCGS) technology at the scale needed to achieve a significant and meaningful reduction in CO2 emissions requires knowledge of the available CO2 storage capacity. CO2 storage capacity assessments may be conducted at various scales-in decreasing order of size and increasing order of resolution:...
Linkages between Alaskan sockeye salmon abundance, growth at sea, and climate, 1955-2002
G.T. Ruggerone, J.L. Nielsen, J. Bumgarner
2007, Deep-Sea Research Part II: Topical Studies in Oceanography (54) 2776-2793
We tested the hypothesis that increased growth of salmon during early marine life contributed to greater survival and abundance of salmon following the 1976/1977 climate regime shift and that this, in turn, led to density-dependent reductions in growth during late marine stages. Annual measurements of Bristol Bay (Bering Sea) and...
Chronology and tectonic controls of late tertiary deposition in the southwestern Tian Shan foreland, NW China
R.V. Heermance, J. Chen, D.W. Burbank, C. Wang
2007, Basin Research (19) 599-632
Magnetostratigraphy from the Kashi foreland basin along the southern margin of the Tian Shan in Western China defines the chronology of both sedimentation and the structural evolution of this collisional mountain belt. Eleven magnetostratigraphic sections representing ???13 km of basin strata provide a two- and three-dimensional record of continuous deposition...
Natural restoration of degraded rangeland ecosystem in Heshan hilly land
R. Hai, D. Weibing, W. Jun, Y. Zuoyue, G. Qinfeng
2007, Acta Ecologica Sinica (27) 3593-3600
This study examined the 20-yr trend of natural restoration of a degraded rangeland ecosystem after disturbance in Heshan hilly land. The results showed that herbs and shrubs were the dominant plants in the community and only a small number of the shade-intolerant tree species had invaded, showing the characteristics of...
Attenuation of ground-motion spectral amplitudes in southeastern Australia
T.I. Allen, P.R. Cummins, T. Dhu, J.F. Schneider
2007, Bulletin of the Seismological Society of America (97) 1279-1292
A dataset comprising some 1200 weak- and strong-motion records from 84 earthquakes is compiled to develop a regional ground-motion model for southeastern Australia (SEA). Events were recorded from 1993 to 2004 and range in size from moment magnitude 2.0 ??? M ??? 4.7. The decay of vertical-component Fourier spectral amplitudes...
Dynamics of cover, UV-protective pigments, and quantum yield in biological soil crust communities of an undisturbed Mojave Desert shrubland
Jayne Belnap, Susan L. Phillips, Stanley D. Smith
2007, Flora (202) 674-686
Biological soil crusts are an integral part of dryland ecosystems. We monitored the cover of lichens and mosses, cyanobacterial biomass, concentrations of UV-protective pigments in both free-living and lichenized cyanobacteria, and quantum yield in the soil lichen species Collema in an undisturbed Mojave Desert shrubland. During our sampling time, the...
Establishing a baseline and faunal history in amphibian monitoring programs: The amphibians of Harris Neck, GA
C.K. Dodd Jr., W.J. Barichivich
2007, Southeastern Naturalist (6) 125-134
We conducted an intensive inventory of Harris Neck National Wildlife Refuge in coastal Georgia to determine the feasibility of establishing an amphibian monitoring program at this location. Thirteen semi-aquatic amphibian species were identified at 21 locations. Amphibian species richness at Harris Neck was similar to that of nearby barrier islands....
Diverse dinosaur-dominated ichnofaunas from the Potomac Group (Lower Cretaceous) Maryland
Ray Stanford, Martin G. Lockley, Robert E. Weems
2007, Ichnos: An International Journal for Plant and Animal Traces (14) 155-173
Until recently fossil footprints were virtually unknown from the Cretaceous of the eastern United States. The discovery of about 300 footprints in iron-rich siliciclastic facies of the Patuxent Formation (Potomac Group) of Aptian age is undoubtedly one of the most significant Early Cretaceous track discoveries since the Paluxy track discoveries...
Sizing up earthquake damage: Differing points of view
S. Hough, A. Bolen
2007, Geotimes (52) 46-48
When a catastrophic event strikes an urban area, many different professionals hit the ground running. Emergency responders respond, reporters report, and scientists and engineers collect and analyze data. Journalists and scientists may share interest in these events, but they have very different missions. To a journalist, earthquake damage is news....
Remote sensing of particle backscattering in Chesapeake Bay: a 6-year SeaWiFS retrospective view
D.G. Zawada, C. Hu, T. Clayton, Z. Chen, J. C. Brock, F. E. Muller-Karger
2007, Estuarine, Coastal and Shelf Science (73) 792-806
Traditional field techniques to monitor water quality in large estuaries, such as boat-based surveys and autonomous moored sensors, generally provide limited spatial coverage. Satellite imagery potentially can be used to address both of these limitations. Here, we show that satellite-based observations are useful for inferring total-suspended-solids (TSS) concentrations in estuarine...
Estimating superpopulation size and annual probability of breeding for pond-breeding salamanders
K.E. Kinkead, David L. Otis
2007, Herpetologica (63) 151-162
It has long been accepted that amphibians can skip breeding in any given year, and environmental conditions act as a cue for breeding. In this paper, we quantify temporary emigration or nonbreeding probability for mole and spotted salamanders (Ambystoma talpoideum and A. maculatum). We estimated that 70% of mole salamanders...
Characterization of low-pathogenicity H5N1 avian influenza viruses from North America
Erica Spackman, D. E. Swayne, D. L. Suarez, D. A. Senne, J. C. Pedersen, M. L. Killian, J. Pasick, K. Handel, S. P. S. Pillai, C. #NAME? Lee, D. Stallknecht, R. Slemons, Hon S. Ip, T. Deliberto
2007, Journal of Virology (81) 11612-11619
Wild-bird surveillance in North America for avian influenza (AI) viruses with a goal of early identification of the Asian H5N1 highly pathogenic AI virus has identified at least six low-pathogenicity H5N1 AI viruses between 2004 and 2006. The hemagglutinin (HA) and neuraminidase (NA) genes from all 6 H5N1 viruses and...
Molecular mechanisms of continuous light inhibition of Atlantic salmon parr-smolt transformation
S.O. Stefansson, Tom O. Nilsen, Lars O.E. Ebbesson, A. Wargelius, Steffen S. Madsen, B. Th Bjornsson, S. D. McCormick
2007, Aquaculture (273) 235-245
Atlantic salmon (Salmo salar) rely on changes in photoperiod for the synchronization of the developmental events constituting the parr-smolt transformation. In the absence of photoperiod cues, parr-smolt transformation is incomplete, and such 'pseudo-smolts' normally fail to adapt to seawater. The present study addresses the endocrine and molecular mechanisms controlling the...
Scales of equilibrium and disequilibrium during cleavage formation in chlorite and biotite-grade phyllites, SE Vermont
C. K. McWilliams, R. P. Wintsch, Michael J. Kunk
2007, Journal of Metamorphic Geology (25) 895-913
Detailed electron microprobe analyses of phyllosilicates in crenulated phyllites from south-eastern Vermont show that grain-scale zoning is common, and sympathetic zoning in adjacent minerals is nearly universal. We interpret this to reflect a pressure-solution mechanism for cleavage development, where precipitation from a very small fluid reservoir fractionated that fluid. Multiple...
Temporal and spatial aspects of peatland initiation following deglaciation in North America
E. Gorham, C. Lehman, A. Dyke, J. Janssens, L. Dyke
2007, Quaternary Science Reviews (26) 300-311
A set of simple ecological models accounts well for the cumulative initiation of peatlands throughout North America in relation to glacial retreat. The most parsimonious form incorporates, first, a delay term to account for the lag during which newly deglaciated land became suitable for peatland initiation and, second, an intrinsic...
