Eruptive history and tectonic setting of Medicine Lake Volcano, a large rear-arc volcano in the southern Cascades
Julie M. Donnelly-Nolan, Timothy L. Grove, M. A. Lanphere, Duane E. Champion, David W. Ramsey
2008, Journal of Volcanology and Geothermal Research (177) 313-328
Medicine Lake Volcano (MLV), located in the southern Cascades ∼ 55 km east-northeast of contemporaneous Mount Shasta, has been found by exploratory geothermal drilling to have a surprisingly silicic core mantled by mafic lavas. This unexpected result is very different from the long-held view derived from previous mapping of exposed geology that...
Compositional mapping of Saturn's satellite Dione with Cassini VIMS and implications of dark material in the Saturn system
R. N. Clark, J. M. Curchin, R. Jaumann, D. P. Cruikshank, R. H. Brown, T.M. Hoefen, K. Stephan, Johnnie N. Moore, B. J. Buratti, K. H. Baines, P. D. Nicholson, R.M. Nelson
2008, Icarus (193) 372-386
Cassini VIMS has obtained spatially resolved imaging spectroscopy data on numerous satellites of Saturn. A very close fly-by of Dione provided key information for solving the riddle of the origin of the dark material in the Saturn system. The Dione VIMS data show a pattern of bombardment of fine, sub-0.5-??m...
Complex seasonal patterns of primary producers at the land-sea interface
J. E. Cloern, A.D. Jassby
2008, Ecology Letters (11) 1294-1303
Seasonal fluctuations of plant biomass and photosynthesis are key features of the Earth system because they drive variability of atmospheric CO2, water and nutrient cycling, and food supply to consumers. There is no inventory of phytoplankton seasonal cycles in nearshore coastal ecosystems where forcings from ocean,...
Multiple plagioclase crystal populations identified by crystal size distribution and in situ chemical data: Implications for timescales of magma chamber processes associated with the 1915 eruption of Lassen Peak, CA
M.J. Salisbury, W.A. Bohrson, M.A. Clynne, F.C. Ramos, P. Hoskin
2008, Journal of Petrology (49) 1755-1780
Products of the 1915 Lassen Peak eruption reveal evidence for a magma recharge–magma mixing event that may have catalyzed the eruption and from which four compositional members were identified: light dacite, black dacite, andesitic inclusion, and dark andesite. Crystal size distribution, textural, and in situ chemical (major and trace element...
Key elements of regional seismic velocity models for long period ground motion simulations
T.M. Brocher
2008, Journal of Seismology (12) 217-221
Regional 3-D seismic velocity models used for broadband strong motion simulations must include compressional-wave velocity (Vp), shear-wave velocity (Vs), intrinsic attenuation (Qp, Qs), and density. Vs and Qs are the most important of these parameters because the strongest ground motions are generated chiefly by shear- and surface-wave arrivals. Because Vp...
Seismic hazard in the Istanbul metropolitan area: A preliminary re-evaluation
E. Kalkan, Polat Gulkan, N.Y. Ozturk, M. Çelebi
2008, Journal of Earthquake Engineering (12) 151-164
In 1999, two destructive earthquakes (M7.4 Kocaeli and M7.2 Duzce) occurred in the north west of Turkey and resulted in major stress-drops on the western segment of the North Anatolian Fault system where it continues under the Marmara Sea. These undersea fault segments were recently explored using bathymetric and reflection...
Kaguyak dome field and its Holocene caldera, Alaska Peninsula
J. Fierstein, W. Hildreth
2008, Journal of Volcanology and Geothermal Research (177) 340-366
Kaguyak Caldera lies in a remote corner of Katmai National Park, 375 km SW of Anchorage, Alaska. The 2.5-by-3-km caldera collapsed ~ 5.8 ± 0.2 ka (14C age) during emplacement of a radial apron of poorly pumiceous crystal-rich dacitic pyroclastic flows (61–67% SiO2). Proximal pumice-fall deposits are thin...
A multi-model framework for simulating wildlife population response to land-use and climate change
B.H. McRae, N.H. Schumaker, R.B. McKane, R. T. Busing, A.M. Solomon, C.A. Burdick
2008, Ecological Modelling (219) 77-91
Reliable assessments of how human activities will affect wildlife populations are essential for making scientifically defensible resource management decisions. A principle challenge of predicting effects of proposed management, development, or conservation actions is the need to incorporate multiple biotic and abiotic factors, including land-use and climate change, that interact to...
Relations between and among contaminant concentrations and biomarkers in black bass (Micropterus spp.) and common carp (Cyprinus carpio) from large U.S. rivers, 1995-2004
J.E. Hinck, C. J. Schmitt, Mark R. Ellersieck, D. E. Tillitt
2008, Journal of Environmental Monitoring (10) 1499-1518
Environmental contaminant and biomarker monitoring data from major U.S. river basins were summarized for black bass (Micropterus spp.) and common carp (Cyprinus carpio) sampled over a nine year period. Cumulative frequency distributions revealed taxon differences for many organochlorine residue concentrations, elemental contaminant concentrations, and biomarkers, but few gender differences were...
Zero-inflated modeling of fish catch per unit area resulting from multiple gears: Application to channel catfish and shovelnose sturgeon in the Missouri River
A. Arab, M. L. Wildhaber, C. K. Wikle, C.N. Gentry
2008, North American Journal of Fisheries Management (28) 1044-1058
Fisheries studies often employ multiple gears that result in large percentages of zero values. We considered a zero-inflated Poisson (ZIP) model with random effects to address these excessive zeros. By employing a Bayesian ZIP model that simultaneously incorporates data from multiple gears to analyze data from the Missouri River, we...
Amphipod densities and indices of wetland quality across the upper-Midwest, USA
M.J. Anteau, A. D. Afton
2008, Wetlands (28) 184-196
Nutritional, behavioral, and diet data for lesser scaup (Aythya affinis [Eyton, 1838]) indicates that there has been a decrease in amphipod (Gammarus lacustris [G. O. Sars, 1863] and Hyalella azteca [Saussure, 1858]) density and wetland quality throughout the upper-Midwest, USA. Accordingly, we estimated densities of Gammarus and Hyalella in six...
Ocean forecasting in terrain-following coordinates: Formulation and skill assessment of the Regional Ocean Modeling System
D.B. Haidvogel, H. Arango, W.P. Budgell, B.D. Cornuelle, E. Curchitser, Lorenzo E. Di, K. Fennel, W.R. Geyer, A.J. Hermann, L. Lanerolle, J. Levin, J.C. McWilliams, A.J. Miller, A.M. Moore, T.M. Powell, A.F. Shchepetkin, C. R. Sherwood, R. P. Signell, J.C. Warner, J. Wilkin
2008, Journal of Computational Physics (227) 3595-3624
Systematic improvements in algorithmic design of regional ocean circulation models have led to significant enhancement in simulation ability across a wide range of space/time scales and marine system types. As an example, we briefly review the Regional Ocean Modeling System, a member of a general class of three-dimensional, free-surface, terrain-following...
Impact of West Nile virus and other mortality factors on American white pelicans at breeding colonies in the northern plains of North America
M.A. Sovada, P.J. Pietz, K. A. Converse, D. Tommy, Erik K. Hofmeister, P. Scherr, Hon S. Ip
2008, Biological Conservation (141) 1021-1031
American white pelicans (Pelecanus erythrorhynchos) are colonial-nesting birds and their breeding sites are concentrated in a few small areas, making this species especially vulnerable to factors that can influence productivity, such as disease, disturbance, predation, weather events and loss of nesting habitat. Nearly half of the American white pelican population...
Deformation and stress-change modeling at Sierra Negra volcano, Galapagos, from ENVISAT INSAR and GPS observations
Sigurjon Jonsson, W.W. Chadwick, Michael Poland, D. Geist
2008, Conference Paper, European Space Agency, (Special Publication) ESA SP
We use radar interferograms and GPS observations to constrain models of magma accumulation and faulting at Sierra Negra volcano, Galápagos, during the years before its 2005 eruption. The data have shown ~5 m of pre-eruption uplift and multiple trapdoor faulting events on an intra-caldera fault system. We find the...
Organic nitrogen chemistry during low-grade metamorphism
J.-P. Boudou, A. Schimmelmann, M. Ader, Maria Mastalerz, M. Sebilo, L. Gengembre
2008, Geochimica et Cosmochimica Acta (72) 1199-1221
Most of the organic nitrogen (Norg) on Earth is disseminated in crustal sediments and rocks in the form of fossil nitrogen-containing organic matter. The chemical speciation of fossil Norg within the overall molecular structure of organic matter changes with time and heating during burial. Progressive thermal evolution of organic matter...
Endocrine systems in juvenile anadromous and landlocked Atlantic salmon (Salmo salar): Seasonal development and seawater acclimation
Tom O. Nilsen, Lars O.E. Ebbesson, P. Kiilerich, B. Th Bjornsson, Steffen S. Madsen, S. D. McCormick, S.O. Stefansson
2008, General and Comparative Endocrinology (155) 762-772
The present study compares developmental changes in plasma levels of growth hormone (GH), insulin-like growth factor I (IGF-I) and cortisol, and mRNA levels of their receptors and the prolactin receptor (PRLR) in the gill of anadromous and landlocked Atlantic salmon during the spring parr-smolt transformation (smoltification) period and following four...
Diverse deformation patterns of Aleutian volcanoes from InSAR
Z. Lu, D. Dzurisin, C. Wicks Jr., J. Power
2008, Conference Paper, European Space Agency, (Special Publication) ESA SP
Interferometric synthetic aperture radar (InSAR) is capable of measuring ground-surface deformation with centimeter-to-subcentimeter precision at a spatial resolution of tens of meters over an area of hundreds to thousands of square kilometers. With its global coverage and all-weather imaging capability, InSAR has become an increasingly important measurement technique for constraining...
Storm-driven sediment transport in Massachusetts Bay
J.C. Warner, B. Butman, P.S. Dalyander
2008, Continental Shelf Research (28) 257-282
Massachusetts Bay is a semi-enclosed embayment in the western Gulf of Maine about 50 km wide and 100 km long. Bottom sediment resuspension is controlled predominately by storm-induced surface waves and transport by the tidal- and wind-driven circulation. Because the Bay is open to the northeast, winds from the northeast...
Comparison of total mercury and methylmercury cycling at five sites using the small watershed approach
J. B. Shanley, Mast M. Alisa, K. Campbell, G. R. Aiken, D. P. Krabbenhoft, R. J. Hunt, J.F. Walker, P. F. Schuster, A. Chalmers, Brent T. Aulenbach, N.E. Peters, M. Marvin-DiPasquale, D. W. Clow, M.M. Shafer
2008, Environmental Pollution (154) 143-154
The small watershed approach is well-suited but underutilized in mercury research. We applied the small watershed approach to investigate total mercury (THg) and methylmercury (MeHg) dynamics in streamwater at the five diverse forested headwater catchments of the US Geological Survey Water, Energy, and...
Paleomagnetism of Proterozoic mafic dikes from the Tobacco Root Mountains, southwest Montana
S. S. Harlan, J. Wm Geissman, L.W. Snee
2008, Precambrian Research (163) 239-264
Paleomagnetic data from Proterozoic mafic dikes in southwestern Montana provides evidence for two distinct episodes of subparallel dike emplacement at ca. 1450 and 780 Ma. Published geochemical data from dikes in the southern Tobacco Root Mountains has identified three distinct compositional groups, termed groups A, B, and C. Geochronological data...
The persistence of lead from past gasoline emissions and mining drainage in a large riparian system: Evidence from lead isotopes in the Sacramento River, California
C.E. Dunlap, Charles N. Alpers, R. Bouse, Howard E. Taylor, D.M. Unruh, A.R. Flegal
2008, Geochimica et Cosmochimica Acta (72) 5935-5948
Lead concentrations and isotope ratios measured in river water colloids and streambed sediment samples along 426 km of the Sacramento River, California reveal that the influence of lead from the historical mining of massive sulfide deposits in the West Shasta Cu-mining district (at the...
The Lower Triassic Sorkh Shale Formation of the Tabas Block, east central Iran: Succesion of a failed-rift basin at the Paleotethys margin
Y. Lasemi, M. Ghomashi, H. Amin-Rasouli, A. Kheradmand
2008, Carbonates and Evaporites (23) 21-38
The Lower Triassic Sorkh Shale Formation is a dominantly red colored marginal marine succession deposited in the north-south trending Tabas Basin of east central Iran. It is correlated with the unconformity-bounded lower limestone member of the Elika Formation of the Alborz Mountains of northern Iran. The Sorkh Shale is bounded...
Implications of black-tailed prairie dog spatial dynamics to black-footed ferrets
D.S. Jachowski, J.J. Millspaugh, E. Biggins, T.M. Livieri, Marc R. Matchett
2008, Natural Areas Journal (28) 14-25
The spatial dynamics of black-tailed prairie dog (Cynomys ludovicianus) colonies affect the utility of these environments for other wildlife, including the endangered black-footed ferret (Mustela nigripes). We used location data of active and inactive black-tailed prairie dog burrows to investigate colony structure, spatial distribution, and patch dynamics of two colonies...
Avian wildlife mortality events due to salmonellosis in the United States, 1985-2004
A.J. Hall, E.K. Saito
2008, Journal of Wildlife Diseases (44) 585-593
Infection with Salmonella spp. has long been recognized in avian wildlife, although its significance in causing avian mortality, and its zoonotic risk, is not well understood. This study evaluates the role of Salmonella spp. in wild bird mortality events in the United States from 1985 through 2004. Analyses were performed to calculate the frequency...
Trichinella murrelli in scavenging mammals from south-central Wisconsin, USA
D.E. Hill, M.D. Samuel, C.A. Nolden, N. Sundar, D.S. Zarlenga, J. P. Dubey
2008, Journal of Wildlife Diseases (44) 629-635
Tissues and serum from 59 raccoons (Procyon lotor), 42 coyotes (Canis latrans), and seven Striped Skunks (Mephitis mephitis) collected in Dane and Iowa Counties, Wisconsin, USA, between October 2005 and March 2006 were microscopically and serologically examined for the presence of Trichinella spp. Encapsulated larvae were found on compression slides...
