The curved 14C vs. δ13C relationship in dissolved inorganic carbon: A useful tool for groundwater age- and geochemical interpretations
Liang-Feng Han, Niel Plummer, Pradeep Aggarwal
2014, Chemical Geology (387) 111-125
Determination of the 14C content of dissolved inorganic carbon (DIC) is useful for dating of groundwater. However, in addition to radioactive decay, the 14C content in DIC (14CDIC) can be affected by many geochemical and physical processes and numerous models have been proposed to refine radiocarbon ages of DIC in...
Correlations in distribution and concentration of calcium, copper and iron with zinc in isolated extracellular deposits associated with age-related macular degeneration
Jane M Flinn, Peter Kakalec, Ryan Tappero, Blair F. Jones, Imre Lengyel
2014, Metallomics (6) 1223-1228
Zinc (Zn) is abundantly enriched in sub-retinal pigment epithelial (RPE) deposits, the hallmarks of age-related macular degeneration (AMD), and is thought to play a role in the formation of these deposits. However, it is not known whether Zn is the only metal relevant for sub-RPE deposit formation. Because of their...
Geophysical investigations of the geologic and hydrothermal framework of the Pilgrim Springs Geothermal Area, Alaska
Jonathan M.G. Glen, Darcy McPhee, Paul A. Bedrosian
2014, Conference Paper, Proceedings, Thirty-Ninth Workshop on Geothermal Reservoir Engineering
Pilgrim Hot Springs, located on the Seward Peninsula in west-central Alaska, is characterized by hot springs, surrounding thawed regions, and elevated lake temperatures. The area is of interest because of its potential for providing renewable energy for Nome and nearby rural communities. We performed ground and airborne geophysical investigations of...
13.3 – Stable Isotope Geochemistry of Mineral Deposits
W.C. Pat Shanks III
2014, Book chapter, Reference module in earth systems and environmental sciences: Treatise on geochemistry (Second Edition)
In this chapter, the intent is to summarize the results of traditional stable isotope studies (mainly H, B, O, C, and S) that have greatly contributed to the understanding of ore-forming processes over the last 60 years and to provide an up-to-date assessment of the application of new nontraditional isotope...
Monitoring conterminous United States (CONUS) land cover change with Web-Enabled Landsat Data (WELD)
M.C. Hansen, Alexey Egorov, P.V. Potapov, S.V. Stehman, A. Tyukavina, S.A. Turubanova, David P. Roy, S.J. Goetz, Thomas R. Loveland, J. Ju, A. Kommareddy, Valeriy Kovalskyy, C. Forsyth, T. Bents
2014, Remote Sensing of Environment (140) 466-484
Forest cover loss and bare ground gain from 2006 to 2010 for the conterminous United States (CONUS) were quantified at a 30 m spatial resolution using Web-Enabled Landsat Data available from the USGS Center for Earth Resources Observation and Science (EROS) (http://landsat.usgs.gov/WELD.php). The approach related multi-temporal WELD metrics and expert-derived...
Major and trace element geochemistry and background concentrations for soils in Connecticut
Craig J. Brown, Margaret A. Thomas
2014, Northeastern Geoscience (32) 1-37
Soil samples were collected throughout Connecticut (CT) to determine the relationship of soil chemistry with the underlying geology and to better understand background concentrations of major and trace elements in soils. Soil samples were collected (1) from the upper 5 cm of surficial soil at 100 sites, (2) from the...
Dispersion analysis of passive surface-wave noise generated during hydraulic-fracturing operations
Farnoush Forghani-Arani, Mark Willis, Roel Snieder, Seth S. Haines, Jyoti Behura, Mike Batzle, Michael Davidson
2014, Journal of Applied Geophysics (111) 129-134
Surface-wave dispersion analysis is useful for estimating near-surface shear-wave velocity models, designing receiver arrays, and suppressing surface waves. Here, we analyze whether passive seismic noise generated during hydraulic-fracturing operations can be used to extract surface-wave dispersion characteristics. Applying seismic interferometry to noise measurements, we extract surface waves by cross-correlating several...
Spectroscopy from Space
Roger N. Clark, Gregg A. Swayze, Robert R. Carlson, Will Grundy, Keith Noll
2014, Reviews in Mineralogy and Geochemistry (78) 399-446
This chapter reviews detection of materials on solid and liquid (lakes and ocean) surfaces in the solar system using ultraviolet to infrared spectroscopy from space, or near space (high altitude aircraft on the Earth), or in the case of remote objects, earth-based and earth-orbiting telescopes. Point spectrometers and imaging spectrometers...
The temperature-productivity squeeze: Constraints on brook trout growth along an Appalachian river continuum
J. Todd Petty, David Thorne, Brock M. Huntsman, Patricia M. Mazik
2014, Hydrobiologia (727) 151-166
We tested the hypothesis that brook trout growth rates are controlled by a complex interaction of food availability, water temperature, and competitor density. We quantified trout diet, growth, and consumption in small headwater tributaries characterized as cold with low food and high trout density, larger tributaries characterized as cold with...
Carbonate rocks of the Seward Peninsula, Alaska: Their correlation and paleogeographic significance
Julie A. Dumoulin, Alta Harris, John E. Repetski
2014, GSA Special Papers (506) 59-110
Paleozoic carbonate strata deposited in shallow platform to off-platform settings occur across the Seward Peninsula and range from unmetamorphosed Ordovician–Devonian(?) rocks of the York succession in the west to highly deformed and metamorphosed Cambrian–Devonian units of the Nome Complex in the east. Faunal and lithologic correlations indicate that early Paleozoic...
New ichnological, paleobotanical and detrital zircon data from an unnamed rock unit in Yukon-Charley Rivers National Preserve (Cretaceous: Alaska): Stratigraphic implications for the region
Anthony R. Fiorillo, Federico Fanti, Chad Hults, Stephen T Hasiotis
2014, Palaios (29) 16-26
A paleontological reconnaissance survey on Cretaceous and Paleogene terrestrial units along the Yukon River drainage through much of east-central Alaska has provided new chronostratigraphic constraints, paleoclimatological data, and the first information on local biodiversity within an ancient, high-latitude ecosystem. The studied unnamed rock unit is most notable for its historic...
Sulfur and oxygen isotopic study of Paleozoic sediment-hosted Zn-Pb(-Ag-Au-Ba-F) deposits and associated hydrothermal alteration zones in the Nome Complex, Seward Peninsula, Alaska
W.C. Pat Shanks III, John F. Slack, Alison B. Till, Roland Thurston, Pamela Gemery-Hill
2014, GSA Special Papers (506) 235-258
Results of sulfur and oxygen isotope studies of sedimentary exhalative (SEDEX) Zn-Pb(-Ag-Au-Ba-F) deposits hosted in metamorphosed Paleozoic clastic and carbonate rocks of the Nome Complex, Seward Peninsula, Alaska, are consistent with data for similar deposits worldwide. Stable isotopic studies of the Nome Complex are challenging because the rocks have...
Influence of variable rainbow smelt and gizzard shad abundance on walleye diets and growth
Mark J. Fincel, Daniel J. Dembkowski, Steven R. Chipps
2014, Lake and Reservoir Management (30) 258-267
Prey availability influences growth and condition of walleye (Sander vitreus) in large systems. In Lake Oahe, South Dakota, rainbow smelt (Osmerus mordax) and gizzard shad (Dorosoma cepedianum) are primary prey of walleye, but their abundance varies substantially year to year. To evaluate the influence of gizzard...
Distributed Evaluation of Local Sensitivity Analysis (DELSA), with application to hydrologic models
O. Rakovec, Mary C. Hill, M.P. Clark, A. H. Weerts, A. J. Teuling, R. Uijlenhoet
2014, Water Resources Research (50) 409-426
This paper presents a hybrid local-global sensitivity analysis method termed the Distributed Evaluation of Local Sensitivity Analysis (DELSA), which is used here to identify important and unimportant parameters and evaluate how model parameter importance changes as parameter values change. DELSA uses derivative-based “local” methods to obtain the distribution of parameter...
Normative standards for land use in Vermont: Implications for biodiversity
Charles A. Bettigole, Therese M. Donovan, Robert Manning, John Austin
2014, Biological Conservation (169) 392-400
The conversion of natural lands to developed uses poses a great threat to global terrestrial biodiversity. Natural resource managers, tasked with managing wildlife as a public trust, require techniques for predicting how much and where wildlife habitat is likely to be converted in the future. Here, we develop a methodology to estimate the “social carrying...
Incorporating detection probability into northern Great Plains pronghorn population estimates
Christopher N. Jacques, Jonathan A. Jenks, Troy W. Grovenburg, Robert W. Klaver, Christopher S. DePerno
2014, Journal of Wildlife Management (78) 164-174
Pronghorn (Antilocapra americana) abundances commonly are estimated using fixed-wing surveys, but these estimates are likely to be negatively biased because of violations of key assumptions underpinning line-transect methodology. Reducing bias and improving precision of abundance estimates through use of detection probability and mark-resight models may allow for more responsive pronghorn...
Effects of iron on optical properties of dissolved organic matter
Brett Poulin, Joseph N. Ryan, George R. Aiken
2014, Environmental Science & Technology (48) 10098-10106
Iron is a source of interference in the spectroscopic analysis of dissolved organic matter (DOM); however, its effects on commonly employed ultraviolet and visible (UV–vis) light adsorption and fluorescence measurements are poorly defined. Here, we describe the effects of iron(II) and iron(III) on the UV–vis absorption and fluorescence of solutions...
A new map of global ecological land units — An ecophysiographic stratification approach
Roger Sayre, Jack Dangermond, Charlie Frye, Randy Vaughan, Peter Aniello, Sean P. Breyer, Douglas Cribbs, Dabney Hopkins, Richard Nauman, William Derrenbacher, Dawn J. Wright, Clint Brown, Charles Convis, Jonathan H. Smith, Laurence Benson, D. Paco VanSistine, Harumi Warner, Jill Janene Cress, Jeffrey J. Danielson, Sharon L. Hamann, Thomas Cecere, Ashwan D. Reddy, Devon Burton, Andrea Grosse, Diane TRUE, Marc Metzger, Jens Hartmann, Nils Moosdorf, Hans Durr, Marc Paganini, Pierre Defourny, Olivier Arino, Simone Maynard, Mark Anderson, Patrick Comer
2014, Book
In response to the need and an intergovernmental commission for a high resolution and data-derived global ecosystem map, land surface elements of global ecological pattern were characterized in an ecophysiographic stratification of the planet. The stratification produced 3,923 terrestrial ecological land units (ELUs) at a base resolution of 250 meters....
Triggered aseismic slip adjacent to the 6 February 2013 Mw 8.0 Santa Cruz Islands megathrust earthquake
Gavin P. Hayes, Kevin P. Furlong, Harley M. Benz, Matthew W. Herman
2014, Earth and Planetary Science Letters (388) 265-272
Aseismic or slow slip events have been observed in many subduction zones, but whether they affect the occurrence of earthquakes or result from stress changes caused by nearby events is unclear. In an area lacking direct geodetic observations, inferences can be made from seismological studies of co-seismic slip, associated stress...
Change-in-ratio
Mark S. Udevitz
2014, Book chapter, Encyclopedia of Environmetrics
Change-in-ratio (CIR) methods are used to estimate parameters for ecological populations subject to differential removals from population subclasses. Subclasses can be defined according to criteria such as sex, age, or size of individuals. Removals are generally in the form of closely monitored sport or commercial harvests. Estimation is based on...
Toxicokinetics and coagulopathy threshold of the rodenticide diphacinone in eastern screech-owls (Megascops asio)
Barnett A. Rattner, K.E. Horak, Rebecca S. Lazarus, D.A. Goldade, J. J. Johnston
2014, Environmental Toxicology and Chemistry (33) 74-81
In the United States, new regulations on second-generation anticoagulant rodenticides will likely be offset by expanded use of first-generation anticoagulant rodenticides. In the present study, eastern screech-owls (Megascops asio) were fed 10 µg diphacinone/g wet weight food for 7 d, and recovery was monitored over a 21-d postexposure period. By day...
Hydrologic connectivity of floodplains, northern Missouri: implications for management and restoration of floodplain forest communities in disturbed landscapes
R. Jacobson, T. Faust
2014, River Research and Applications (30) 269-286
Hydrologic connectivity between the channel and floodplain is thought to be a dominant factor determining floodplain processes and characteristics of floodplain forests. We explored the role of hydrologic connectivity in explaining floodplain forest community composition along streams in northern Missouri, USA. Hydrologic analyses at 20 streamgages (207–5827 km2 area) document that...
Spatially explicit modeling of 1992-2100 land cover and forest stand age for the conterminous United States
Terry L. Sohl, Kristi L. Sayler, Michelle Bouchard, Ryan R. Reker, Aaron M. Friesz, Stacie L. Bennett, Benjamin M. Sleeter, Rachel R. Sleeter, Tamara Wilson, Christopher E. Soulard, Michelle Knuppe, Travis Van Hofwegen
2014, Ecological Applications (24) 1015-1036
Information on future land-use and land-cover (LULC) change is needed to analyze the impact of LULC change on ecological processes. The U.S. Geological Survey has produced spatially explicit, thematically detailed LULC projections for the conterminous United States. Four qualitative and quantitative scenarios of LULC change were developed, with characteristics consistent...
Contaminants from Cretaceous black shale: II. Effect of geology, weathering, climate, and land use on salinity and selenium cycling, Mancos Shale landscapes, southwestern United States
Michele L. Tuttle, Juli W. Fahy, John G. Elliott, Richard I. Grauch, Lisa L. Stillings
2014, Applied Geochemistry (46) 72-84
The Cretaceous Mancos Shale (MS) is a known nonpoint source for a significant portion of the salinity and selenium (Se) loads in the Colorado River in the southwestern United States and northwestern corner of Mexico. These two contaminants pose a serious threat to rivers in these arid regions where water...
Contaminants from Cretaceous black shale: I. Natural weathering processes controlling contaminant cycling in Mancos Shale, southwestern United States, with emphasis on salinity and selenium
Michele L. Tuttle, Juli W. Fahy, John G. Elliott, Richard I. Grauch, Lisa L. Stillings
2014, Applied Geochemistry (46) 57-71
Soils derived from black shale can accumulate high concentrations of elements of environmental concern, especially in regions with semiarid to arid climates. One such region is the Colorado River basin in the southwestern United States where contaminants pose a threat to agriculture, municipal water supplies, endangered aquatic species, and water-quality...
