Prospective earthquake forecasts at the Himalayan Front after the 25 April 2015 M 7.8 Gorkha Mainshock
Margaret Segou, Thomas E. Parsons
2016, Seismological Research Letters (87) 816-825
When a major earthquake strikes, the resulting devastation can be compounded or even exceeded by the subsequent cascade of triggered seismicity. As the Nepalese recover from the 25 April 2015 shock, knowledge of what comes next is essential. We calculate the redistribution of crustal stresses and implied earthquake probabilities for...
Ground motions at the outermost limits of seismically triggered landslides
Randall W. Jibson, Edwin L. Harp
2016, Bulletin of the Seismological Society of America (106) 708-719
Over the last few decades, we and our colleagues have conducted field investigations in which we mapped the outermost limits of triggered landslides in four earthquakes: 1987 Whittier Narrows, California (M 5.9), 1987 Superstition Hills, California (M 6.5), 1994 Northridge, California (M 6.7), and 2011 Mineral, Virginia (M 5.8). In an additional two earthquakes,...
Manual hierarchical clustering of regional geochemical data using a Bayesian finite mixture model
Karl J. Ellefsen, David Smith
2016, Applied Geochemistry (75) 200-210
Interpretation of regional scale, multivariate geochemical data is aided by a statistical technique called “clustering.” We investigate a particular clustering procedure by applying it to geochemical data collected in the State of Colorado, United States of America. The clustering procedure partitions the field samples for the entire survey area into...
The new Landsat 8 potential for remote sensing of colored dissolved organic matter (CDOM)
E. Terrence Slonecker, Daniel K. Jones, Brian A. Pellerin
2016, Marine Pollution Bulletin (107) 518-527
Due to a combination of factors, such as a new coastal/aerosol band and improved radiometric sensitivity of the Operational Land Imager aboard Landsat 8, the atmospherically-corrected Surface Reflectance product for Landsat data, and the growing availability of corrected fDOM data from U.S. Geological Survey gaging stations, moderate-resolution remote sensing of...
Increased water deficit decreases Douglas fir growth throughout western US forests
Christina M Restaino, David L. Peterson, Jeremy S. Littell
2016, Proceedings of the National Academy of Sciences of the United States of America (113) 9557-9562
Changes in tree growth rates can affect tree mortality and forest feedbacks to the global carbon cycle. As air temperature increases, evaporative demand also increases, increasing effective drought in forest ecosystems. Using a spatially comprehensive network of Douglas-fir (Pseudotsuga menziesii) chronologies from 122 locations that experience distinctly different climate in...
Seasonal Variability in Vadose zone biodegradation at a crude oil pipeline rupture site
Natasha J. Sihota, Jared J. Trost, Barbara Bekins, Andrew M. Berg, Geoffrey N. Delin, Brent E. Mason, Ean Warren, K. Ulrich Mayer
2016, Vadose Zone Journal (15)
Understanding seasonal changes in natural attenuation processes is critical for evaluating source-zone longevity and informing management decisions. The seasonal variations of natural attenuation were investigated through measurements of surficial CO2 effluxes, shallow soil CO2 radiocarbon contents, subsurface gas concentrations, soil temperature, and volumetric water contents during a 2-yr period. Surficial...
Including land cover change in analysis of greenness trends using all available Landsat 5, 7, and 8 images: A case study from Guangzhou, China (2000–2014)
Zhe Zhu, Yingchun Fu, Curtis Woodcock, Pontus Olofsson, James Vogelmann, Christopher Holden, Min Wang, Shu Dai, Yang Yu
2016, Remote Sensing of Environment (185) 243-257
Remote sensing has proven a useful way of evaluating long-term trends in vegetation “greenness” through the use of vegetation indices like Normalized Differences Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). In particular, analyses of greenness trends have been performed for large areas (continents, for example) in an attempt...
Spatiotemporal patterns of mercury accumulation in lake sediments of western North America
Paul Drevnick, Colin A. Cooke, Daniella Barraza, Jules M. Blais, Kenneth Coale, Brian F. Cumming, Chris Curtis, Biplob Das, William F. Donahue, Collin A. Eagles-Smith, Daniel R. Engstrom, William F. Fitzgerald, Chad V. Furl, John R. Gray, Roland I. Hall, Togwell A. Jackson, Kathleen R. Laird, W. Lyle Lockhart, Robie W. Macdonald, M. Alisa Mast, Callie Mathieu, Derek C.G. Muir, Peter Outridge, Scott Reinemann, Sarah E. Rothenberg, Ana Carolina Ruiz-Fernandex, Louis, Rhea Sanders, Hamed Sanei, Elliott Skierszkan, Peter C. Van Metre, Timothy Veverica, Johan A. Wiklund, Brent B. Wolfe
2016, Science of the Total Environment (568) 1157-1170
For the Western North America Mercury Synthesis, we compiled mercury records from 165 dated sediment cores from 138 natural lakes across western North America. Lake sediments are accepted as faithful recorders of historical mercury accumulation rates, and regional and sub-regional temporal and spatial trends were...
Characterizing supraglacial meltwater channel hydraulics on the Greenland Ice Sheet from in situ observations
Colin J. Gleason, Laurence C. Smith, Vena W. Chu, Carl J. Legleiter, Lincoln H. Pitcher, Brandon T. Overstreet, Asa K. Rennermalm, Richard R. Forster, Kang Yang
2016, Earth Surface Processes and Landforms (41) 2111-2122
Supraglacial rivers on the Greenland ice sheet (GrIS) transport large volumes of surface meltwater toward the ocean, yet have received relatively little direct research. This study presents field observations of channel width, depth, velocity, and water surface slope for nine supraglacial channels on the southwestern GrIS collected between 23 July...
High concentrations of manganese and sulfur in deposits on Murray Ridge, Endeavour Crater, Mars
Raymond E. Arvidson, Steven W. Squyres, Richard V. Morris, Andrew H. Knoll, Ralf Gellert, Benton C. Clark, Jeffrey G. Catalano, Bradley L. Jolliff, Scott M. McLennan, Kenneth E. Herkenhoff, Scott VanBommel, David W. Mittelfehldt, John P. Grotzinger, Edward A. Guinness, Jeffrey R. Johnson, James F. Bell III, William H. Farrand, Nathan Stein, Valerie K. Fox, Matthew P. Golombek, Margaret A. G. Hinkle, Wendy M. Calvin, Paulo A. de Souza Jr.
2016, American Mineralogist (101) 1389-1405
Mars Reconnaissance Orbiter HiRISE images and Opportunity rover observations of the ~22 km wide Noachian age Endeavour Crater on Mars show that the rim and surrounding terrains were densely fractured during the impact crater-forming event. Fractures have also propagated upward into the overlying Burns formation sandstones. Opportunity’s observations show that...
Impact of formation water geochemistry and crude oil biodegradation on microbial methanogenesis
Jenna L. Shelton, Jennifer C. McIntosh, Peter D. Warwick, John E. McCray
2016, Organic Geochemistry (98) 105-117
Converting non-producible crude oil to CH4 via methanogenic crude oil biodegradation in oil reservoirs could serve as one way to increase our energy profile. Yet, field data supporting the direct relationship between methanogenesis and crude oil biodegradation are sparse. Indicators of methanogenesis, based on the formation water and gas geochemistry...
Estimation of peak discharge quantiles for selected annual exceedance probabilities in northeastern Illinois
Thomas M. Over, Riki J. Saito, Andrea G. Veilleux, Padraic S. O’Shea, Jennifer B. Sharpe, David T. Soong, Audrey L. Ishii
2016, Scientific Investigations Report 2016-5050
This report provides two sets of equations for estimating peak discharge quantiles at annual exceedance probabilities (AEPs) of 0.50, 0.20, 0.10, 0.04, 0.02, 0.01, 0.005, and 0.002 (recurrence intervals of 2, 5, 10, 25, 50, 100, 200, and 500 years, respectively) for watersheds in Illinois based on annual maximum peak...
Reconsidering earthquake scaling
Joan S. Gomberg, Aaron G. Wech, Kenneth Creager, K. Obara, Duncan Agnew
2016, Geophysical Research Letters (43) 6243-6251
The relationship (scaling) between scalar moment, M0, and duration, T, potentially provides key constraints on the physics governing fault slip. The prevailing interpretation of M0-T observations proposes different scaling for fast (earthquakes) and slow (mostly aseismic) slip populations and thus fundamentally different driving mechanisms. We show that a single model of slip events within...
Groundwater-flow model for the Wood River Valley aquifer system, south-central Idaho
Jason C. Fisher, James R. Bartolino, Allan H. Wylie, Jennifer Sukow, Michael McVay
2016, Scientific Investigations Report 2016-5080
A three-dimensional numerical model of groundwater flow was developed for the Wood River Valley (WRV) aquifer system, Idaho, to evaluate groundwater and surface-water availability at the regional scale. This mountain valley is located in Blaine County and has a drainage area of about 2,300 square kilometers (888 square miles). The...
Threshold sensitivity of shallow Arctic lakes and sublake permafrost to changing winter climate
Christopher D. Arp, Benjamin M. Jones, Guido Grosse, Allen C. Bondurant, Vladimir E. Romanovksy, Kenneth M. Hinkel, Andrew D. Parsekian
2016, Geophysical Research Letters (43) 6358-6365
Interactions and feedbacks between abundant surface waters and permafrost fundamentally shape lowland Arctic landscapes. Sublake permafrost is maintained when the maximum ice thickness (MIT) exceeds lake depth and mean annual bed temperatures (MABTs) remain below freezing. However, declining MIT since the 1970s is likely causing talik development below...
A spatially explicit suspended-sediment load model for western Oregon
Daniel R. Wise, Jim O’Connor
2016, Scientific Investigations Report 2016-5079
We calibrated the watershed model SPARROW (Spatially Referenced Regressions on Watershed attributes) to give estimates of suspended-sediment loads for western Oregon and parts of northwestern California. Estimates of suspended-sediment loads were derived from a nonlinear least squares regression that related explanatory variables representing landscape and transport conditions to measured suspended-sediment...
Estimating peak-flow frequency statistics for selected gaged and ungaged sites in naturally flowing streams and rivers in Idaho
Molly S. Wood, Ryan L. Fosness, Kenneth D. Skinner, Andrea G. Veilleux
2016, Scientific Investigations Report 2016-5083
The U.S. Geological Survey, in cooperation with the Idaho Transportation Department, updated regional regression equations to estimate peak-flow statistics at ungaged sites on Idaho streams using recent streamflow (flow) data and new statistical techniques. Peak-flow statistics with 80-, 67-, 50-, 43-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual...
The role of habitat filtering in the leaf economics spectrum and plant susceptibility to pathogen infection
Miranda E Welsh, James P. Cronin, Charles E. Mitchell
2016, Journal of Ecology (104) 1768-1777
1.The Leaf Economics Spectrum (LES) describes global covariation in the traits of plant leaves. The LES is thought to arise from biophysical constraints and habitat filtering (ecological selection against unfit trait combinations along environmental gradients). However, the role of habitat filtering in generating the LES has not been tested experimentally. 2.If...
The Maryland Coastal Plain Aquifer Information System: A GIS-based tool for assessing groundwater resources
David C. Andreasen, Mark R. Nardi, Andrew W. Staley, Grufron Achmad, John W. Grace
2016, Special Paper of the Geological Society of America (520) 159-170
Groundwater is the source of drinking water for ∼1.4 million people in the Coastal Plain Province of Maryland (USA). In addition, groundwater is essential for commercial, industrial, and agricultural uses. Approximately 0.757 × 109 L d–1 (200 million gallons/d) were withdrawn in 2010. As a result of decades of withdrawals...
Mercury risk to avian piscivores across western United States and Canada
Allyson K. Jackson, David C. Evers, Collin A. Eagles-Smith, Joshua T. Ackerman, James J. Willacker, John E. Elliott, Jesse M. Lepak, Stacy S. Vander Pol, Colleen E. Bryan
2016, Science of the Total Environment (568) 685-696
The widespread distribution of mercury (Hg) threatens wildlife health, particularly piscivorous birds. Western North America is a diverse region that provides critical habitat to many piscivorous bird species, and also has a well-documented history of mercury contamination from legacy mining and atmospheric deposition. The diversity of landscapes in the west...
Growth rates and ages of deep-sea corals impacted by the Deepwater Horizon oil spill
Nancy G. Prouty, Charles R. Fisher, Amanda W.J. Demopoulos, Ellen R. M. Druffel
2016, Deep-Sea Research Part II: Topical Studies in Oceanography (129) 212
The impact of the April 2010 Deepwater Horizon (DWH) spill on deep-sea coral communities in the Gulf of Mexico (GoM) is still under investigation, as is the potential for these communities to recover. Impacts from the spill include observation of corals covered with flocculent material, with bare skeleton, excessive mucous...
Inferring river bathymetry via Image-to-Depth Quantile Transformation (IDQT)
Carl J. Legleiter
2016, Water Resources Research (52) 3722-3741
Conventional, regression-based methods of inferring depth from passive optical image data undermine the advantages of remote sensing for characterizing river systems. This study introduces and evaluates a more flexible framework, Image-to-Depth Quantile Transformation (IDQT), that involves linking the frequency distribution of pixel values to that of depth. In addition, a...
A synthesis of the basal thermal state of the Greenland Ice Sheet
Joseph A MacGregor, Mark A Fahnestock, Ginny A Catania, Andy Aschwanden, Gary D. Clow, William T. Colgan, Prasad S. Gogineni, Mathieu Morlighem, Sophie M .J. Nowicki, John D Paden, Stephen F. Price, Helene Seroussi
2016, Journal of Geophysical Research F: Earth Surface (121) 1328-1350
The basal thermal state of an ice sheet (frozen or thawed) is an important control upon its evolution, dynamics and response to external forcings. However, this state can only be observed directly within sparse boreholes or inferred conclusively from the presence of subglacial lakes. Here we synthesize spatially extensive inferences...
Regional modeling of large wildfires under current and potential future climates in Colorado and Wyoming, USA
Amanda M. West, Sunil Kumar, Catherine S. Jarnevich
2016, Climatic Change (134) 565-577
Regional analysis of large wildfire potential given climate change scenarios is crucial to understanding areas most at risk in the future, yet wildfire models are not often developed and tested at this spatial scale. We fit three historical climate suitability models for large wildfires (i.e. ≥ 400 ha) in Colorado...
Gravel-bed river floodplains are the ecological nexus of glaciated mountain landscapes
F. Richard Hauer, Harvey Locke, Victoria Dreitz, Mark Hebblewhite, Winsor Lowe, Clint C. Muhlfeld, Cara Nelson, Michael F. Proctor, Stewart B. Rood
2016, Science Advances (2)
Gravel-bed river floodplains in mountain landscapes disproportionately concentrate diverse habitats, nutrient cycling, productivity of biota, and species interactions. Although stream ecologists know that river channel and floodplain habitats used by aquatic organisms are maintained by hydrologic regimes that mobilize gravel-bed sediments, terrestrial ecologists have largely been unaware of the importance...
