High-frequency imaging of elastic contrast and contact area with implications for naturally observed changes in fault properties
Kohei Nagata, Brian D. Kilgore, Nicholas M. Beeler, Masao Nakatani
2014, Journal of Geophysical Research (119) 5855-5875
During localized slip of a laboratory fault we simultaneously measure the contact area and the dynamic fault normal elastic stiffness. One objective is to determine conditions where stiffness may be used to infer changes in area of contact during sliding on nontransparent fault surfaces. Slip speeds between 0.01 and 10...
Effects of 2010 Hurricane Earl amidst geologic evidence for greater overwash at Anegada, British Virgin Islands
Brian F. Atwater, Zamara Fuentes, Robert B. Halley, Uri S. ten Brink, Martitia P. Tuttle
2014, Advances in Geosciences (38) 21-30
A post-hurricane survey of a Caribbean island affords comparisons with geologic evidence for greater overwash at the same place. This comparison, though of limited application to other places, helps calibrate coastal geology for assessment of earthquake and tsunami potential along the Antilles Subduction Zone. The surveyed island, Anegada, is 120 km...
Reconstruction of an early Paleozoic continental margin based on the nature of protoliths in the Nome Complex, Seward Peninsula, Alaska
Alison B. Till, Julie A. Dumoulin, Robert A. Ayuso, John N. Aleinikoff, Jeffrey M. Amato, John F. Slack, W.C. Pat Shanks III
2014, GSA Special Papers
The Nome Complex is a large metamorphic unit that sits along the southern boundary of the Arctic Alaska–Chukotka terrane, the largest of several micro continental fragments of uncertain origin located between the Siberian and Laurentian cratons. The Arctic Alaska–Chukotka terrane moved into its present position during the Mesozoic; its Mesozoic...
Interagency partnership to assess and restore a degraded urban riverine wetland: Dyke Marsh Wildlife Preserve, Virginia
Brent W. Steury, Ronald J. Litwin, Erik T. Oberg, Joseph P. Smoot, Milan J. Pavich, Geoffrey Sanders, Vincent L. Santucci
2014, The George Wright Forum (31) 116-128
The narrow-leaved cattail wetland known as Dyke Marsh formally became a land holding of George Washington Memorial Parkway (GWMP, a unit of the national park system) in 1959, along with a congressional directive to honor a newly-let 30-year commercial sand and gravel dredge-mining lease at the site. Dredging continued until...
Mapping forest height in Alaska using GLAS, Landsat composites, and airborne LiDAR
Birgit Peterson, Kurtis Nelson
2014, Remote Sensing (6) 12409-12426
Vegetation structure, including forest canopy height, is an important input variable to fire behavior modeling systems for simulating wildfire behavior. As such, forest canopy height is one of a nationwide suite of products generated by the LANDFIRE program. In the past, LANDFIRE has relied on a combination of field observations...
Simulated and measured water levels and estimated water-level changes in the Albuquerque area, central New Mexico, 1950-2012
Steven E. Rice, Gretchen P. Oelsner, Charles E. Heywood
2014, Scientific Investigations Map 3305
The City of Albuquerque, the major population center in New Mexico, underwent a more than fivefold population increase between 1950 and 2010. Before 2009, groundwater was the primary source of the City of Albuquerque’s municipal water supply, but since that time, the city has diverted water through the San Juan-Chama...
Estimated 2012 groundwater potentiometric surface and drawdown from predevelopment to 2012 in the Santa Fe Group aquifer system in the Albuquerque metropolitan area, central New Mexico
Rachel I. Powell, Sarah E. McKean
2014, Scientific Investigations Map 3301
Historically, the water-supply requirements of the Albuquerque metropolitan area of central New Mexico were met almost exclusively by groundwater withdrawal from the Santa Fe Group aquifer system. In response to water-level declines, the Albuquerque Bernalillo County Water Utility Authority (ABCWUA) began diverting water from the San Juan-Chama Drinking Water Project...
Estimating landscape resistance to dispersal
Tabitha A. Graves, Richard B. Chandler, J. Andrew Royle, Paul Beier, Katherine C. Kendall
2014, Landscape Ecology (29) 1201-1211
Dispersal is an inherently spatial process that can be affected by habitat conditions in sites encountered by dispersers. Understanding landscape resistance to dispersal is important in connectivity studies and reserve design, but most existing methods use resistance functions with cost parameters that are subjectively chosen by the investigator. We...
Paleoearthquakes at Frazier Mountain, California delimit extent and frequency of past San Andreas Fault ruptures along 1857 trace
Katherine M. Scharer, Ray Weldon II, Ashley Streig, Thomas Fumal
2014, Geophysical Research Letters (41) 4527-4534
Large earthquakes are infrequent along a single fault, and therefore historic, well-characterized earthquakes exert a strong influence on fault behavior models. This is true of the 1857 Fort Tejon earthquake (estimated M7.7–7.9) on the southern San Andreas Fault (SSAF), but an outstanding question is whether the 330 km long rupture...
Fish assemblages, connectivity, and habitat rehabilitation in a diked Great Lakes coastal wetland complex
Kurt P. Kowalski, Michael J. Wiley, Douglas A. Wilcox
2014, Transactions of the American Fisheries Society (143) 1130-1142
Fish and plant assemblages in the highly modified Crane Creek coastal wetland complex of Lake Erie were sampled to characterize their spatial and seasonal patterns and to examine the implications of the hydrologic connection of diked wetland units to Lake Erie. Fyke netting captured 52 species and an abundance of...
WaterQualityWatch and water-quality information bookmark
Franceska D. Wilde
2014, General Information Product 157
WaterQualityWatch is an online resource of the U.S. Geological Survey (USGS) that provides access to continuous real-time measurements of water temperature, specific electrical conductance, pH, dissolved oxygen, turbidity, and nitrate at selected data-collection stations throughout the Nation. Additional online resources of the USGS that pertain to various types of water-quality...
Assessment of undiscovered, technically recoverable oil and gas resources of Armenia, 2014
Timothy R. Klett, Christopher J. Schenk, Craig J. Wandrey, Michael E. Brownfield, Ronald R. Charpentier, Marilyn E. Tennyson, Donald L. Gautier
2014, Fact Sheet 2014-3048
Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean volumes of 1 million barrels of undiscovered, technically recoverable conventional oil and 6 billion cubic feet of undiscovered, technically recoverable conventional natural gas in Armenia....
Parameter optimization, sensitivity, and uncertainty analysis of an ecosystem model at a forest flux tower site in the United States
Yiping Wu, Shuguang Liu, Zhihong Huang, Wende Yan
2014, Journal of Advances in Modeling Earth Systems (6) 405-419
Ecosystem models are useful tools for understanding ecological processes and for sustainable management of resources. In biogeochemical field, numerical models have been widely used for investigating carbon dynamics under global changes from site to regional and global scales. However, it is still challenging to optimize parameters and estimate parameterization uncertainty...
Characterization of the porosity distribution in the upper part of the karst Biscayne aquifer using common offset ground penetrating radar, Everglades National Park, Florida
Gregory S. Mountain, Xavier Comas, Kevin J. Cunningham
2014, Journal of Hydrology (515) 223-236
The karst Biscayne aquifer is characterized by a heterogeneous spatial arrangement of porosity and hydraulic conductivity, making conceptualization difficult. The Biscayne aquifer is the primary source of drinking water for millions of people in south Florida; thus, information concerning the distribution of karst features that concentrate the groundwater flow...
Five centuries of tsunamis and land-level changes in the overlapping rupture area of the 1960 and 2010 Chilean earthquakes
Lisa L. Ely, Marco Cisternas, Robert L. Wesson, Tina Dura
2014, Geology (42) 995-998
A combination of geological and historical records from south-central Chile provides a means to address general questions about the stability of megathrust rupture patches and the range of variation expected among earthquakes and tsunamis along a particular stretch of a subduction zone. The Tirúa River estuary (38.3°S) records four large...
Using regional moment tensors to constrain the kinematics and stress evolution of the 2010–2013 Canterbury earthquake sequence, South Island, New Zealand
Matthew W. Herman, Robert B. Herrmann, Harley M. Benz, Kevin P. Furlong
2014, Tectonophysics (633) 1-15
On September 3, 2010, a MW 7.0 (U.S. Geological Survey moment magnitude) earthquake ruptured across the Canterbury Plains in South Island, New Zealand. Since then, New Zealand GNS Science has recorded over 10,000 aftershocks ML 2.0 and larger, including three destructive ~ MW 6.0 earthquakes near Christchurch. We treat the Canterbury...
Site response in the eastern United States: A comparison of Vs30 measurements with estimates from horizontal:vertical spectral ratios
Daniel E. McNamara, William J. Stephenson, Jackson K. Odum, Robert Williams, Lind Gee
2014, GSA Special Papers (509) 67-79
Earthquake damage is often increased due to local ground-motion amplification caused by soft soils, thick basin sediments, topographic effects, and liquefaction. A critical factor contributing to the assessment of seismic hazard is detailed information on local site response. In order to address and quantify the site response at seismograph stations...
Interpretations of evidence for large Pleistocene paleolakes in the Bonneville basin, western North America: COMMENT on: Bonneville basin shoreline records of large lake intervals during marine isotope stage 3 and the last glacial maximum, by Nishizawa et al. (2013)
Charles G. Oviatt, Margorie A. Chan, Paul W. Jewell, Bruce G. Bills, David B. Madsen, David M. Miller
2014, Palaeogeography, Palaeoclimatology, Palaeoecology (401) 173-176
Nishizawa et al. (2013) argue in support of three large paleolakes in the Bonneville basin during Marine Oxygen Isotope Stage 3 (MIS 3). If true, that would be an important contribution to paleoclimate investigations. However, the key evidence in support of their argument consists of four radiocarbon ages that are...
A mechanistic modeling and data assimilation framework for Mojave Desert ecohydrology
Gene-Hua Crystal Ng, David Bedford, David M. Miller
2014, Water Resources Research (50) 4662-4685
This study demonstrates and addresses challenges in coupled ecohydrological modeling in deserts, which arise due to unique plant adaptations, marginal growing conditions, slow net primary production rates, and highly variable rainfall. We consider model uncertainty from both structural and parameter errors and present a mechanistic model for the shrub Larrea...
U.S. Geological Survey Science for the Wyoming Landscape Conservation Initiative: 2012 annual report
Zachary H. Bowen, Cameron L. Aldridge, Patrick J. Anderson, Timothy J. Assal, Carleton R. Bern, Laura Biewick, Gregory K. Boughton, Natasha B. Carr, Anna D. Chalfoun, Geneva W. Chong, Melanie L. Clark, Bradford C. Fedy, Katharine Foster, Steven L. Garman, Steve Germaine, Matthew G. Hethcoat, Collin G. Homer, Matthew J. Kauffman, Douglas Keinath, Natalie Latysh, Daniel J. Manier, Robert R. McDougal, Cynthia P. Melcher, Kirk A. Miller, Jessica Montag, Christopher J. Potter, Spencer Schell, Sarah L. Shafer, David B. Smith, Michael J. Sweat, Anna B. Wilson
2014, Open-File Report 2014-1093
Southwest Wyoming contains abundant energy resources, wildlife, habitat, open spaces, and outdoor recreational opportunities. Although energy exploration and development have been taking place in the region since the late 1800s, the pace of development for fossil fuels and renewable energy increased significantly in the early 2000s. This and the associated...
Resource partitioning in two stream salamanders, Dicamptodon tenebrosus and Rhyacotriton cascadae, from the Oregon Cascade Mountains
Wynn W. Cudmore, R. Bruce Bury
2014, American Midland Naturalist (172) 191-199
We investigated the potential for resource partitioning between the Coastal giant salamander (Dicamptodon tenebrosus) and the Cascade torrent salamander (Rhyacotriton cascadae) by examining their diet and microhabitats in forest streams. Larval D. tenebrosus and R. cascadae fed primarily upon aquatic insect larvae. We found similar foods in larval and adult...
Wolf population regulation revisited: again
Ronald E. McRoberts, L. David Mech
2014, Journal of Wildlife Management (78) 963-967
The long-accepted conclusion that wolf density is regulated by nutrition was recently challenged, and the conclusion was reached that, at greater levels of prey biomass, social factors such as intraspecific strife and territoriality tend to regulate wolf density. We reanalyzed the data used in that study for 2 reasons: 1)...
Discharge, water quality, and native fish abundance in the Virgin River, Utah, Nevada, and Arizona, in support of Pah Tempe Springs discharge remediation efforts
Matthew P. Miller, Patrick M. Lambert, Thomas B. Hardy
2014, Open-File Report 2014-1104
Pah Tempe Springs discharge hot, saline, low dissolved-oxygen water to the Virgin River in southwestern Utah, which is transported downstream to Lake Mead and the Colorado River. The dissolved salts in the Virgin River negatively influence the suitability of this water for downstream agricultural, municipal, and industrial use. Therefore, various...
Effects of reintroduced beaver (Castor canadensis) on riparian bird community structure along the upper San Pedro River, southeastern Arizona and northern Sonora, Mexico
Glenn E. Johnson, Charles van Riper III
2014, Open-File Report 2014-1121
Chapter 1.—We measured bird abundance and richness along the upper San Pedro River in 2005 and 2006, in order to document how beavers (Castor canadensis) may act as ecosystem engineers after their reintroduction to a desert riparian area in the Southwestern United States. In areas where beavers colonized, we found...
Graptemys gibbonsi Lovich and McCoy -- Pascagoula Map Turtle
Jeffrey E. Lovich, Joshua R. Ennen
2014, Book chapter, Catalogue of American Amphibians and Reptiles
DEFINITION. The Pascagoula Map Turtle, Graptemys gibbonsi, is a large riverine species that exhibits pronounced sexual dimorphism, where females attain a maximum carapace length (CL) of 295 mm and males a maximum of 141 mm (Lovich et al. 2009). Mean adult female CL (248 mm) can be well over twice...
