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Not all publications have extents, not all extents are completely accurate
Difference infiltrometer: a method to measure temporally variable infiltration rates during rainstorms
John A. Moody, Brian A. Ebel
2012, Hydrological Processes (26) 3312-3318
We developed a difference infiltrometer to measure time series of non-steady infiltration rates during rainstorms at the point scale. The infiltrometer uses two, tipping bucket rain gages. One gage measures rainfall onto, and the other measures runoff from, a small circular plot about 0.5-m in diameter. The small size allows...
A comparison among observations and earthquake simulator results for the allcal2 California fault model
Terry. E. Tullis, Keith B. Richards-Dinger, Michael Barall, James H. Dieterich, Edward H. Field, Eric M. Heien, Louise Kellogg, Fred F. Pollitz, John B. Rundle, Michael K. Sachs, Donald L. Turcotte, Steven N. Ward, M. Burak Yikilmaz
2012, Seismological Research Letters (83) 994-1006
In order to understand earthquake hazards we would ideally have a statistical description of earthquakes for tens of thousands of years. Unfortunately the ∼100‐year instrumental, several 100‐year historical, and few 1000‐year paleoseismological records are woefully inadequate to provide a statistically significant record. Physics‐based earthquake simulators can generate arbitrarily long...
Physiography, geology, and land cover of four watersheds in eastern Puerto Rico: Chapter A in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Sheila F. Murphy, Robert F. Stallard, Matthew C. Larsen, William A. Gould
Sheila F. Murphy, editor(s)
2012, Professional Paper 1789-A
Four watersheds with differing geology and land cover in eastern Puerto Rico have been studied on a long-term basis by the U.S. Geological Survey to evaluate water, energy, and biogeochemical budgets. These watersheds are typical of tropical, island-arc settings found in many parts of the world. Two watersheds are located...
Atmospheric inputs to watersheds of the Luquillo Mountains in eastern Puerto Rico: Chapter D in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Robert F. Stallard
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-D
Twenty years of precipitation-chemistry data from the National Atmospheric Deposition Program site at El Verde, Puerto Rico, demonstrate that three major sources control the composition of solutes in rain in eastern Puerto Rico. In order of importance, these sources are marine salts, temperate contamination from the Northern Hemisphere, and Sahara...
Water quality and mass transport in four watersheds in eastern Puerto Rico: Chapter E in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Robert F. Stallard, Sheila F. Murphy
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-E
Water quality of four small watersheds in eastern Puerto Rico has been monitored since 1991 as part of the U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets program. These watersheds represent a montane, humid-tropical environment and differ in geology and land cover. Two watersheds are located on granitic rocks, and...
Hydrology and climate of four watersheds in eastern Puerto Rico: Chapter C in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Sheila F. Murphy, Robert F. Stallard
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-C
Puerto Rico lies directly in the path of the easterly trade winds, which deliver steady rainfall to the mountains and steer tropical wave systems toward the island. Hurricanes and tropical storms derived from these tropical waves differ in frequency and intensity, contributing to substantial interannual variation in precipitation and stream...
Landslides and sediment budgets in four watersheds in eastern Puerto Rico: Chapter F in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Matthew C. Larsen
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-F
The low-latitude regions of the Earth are undergoing profound, rapid landscape change as forests are converted to agriculture to support growing population. Understanding the effects of these land-use changes requires analysis of watershed-scale geomorphic processes to better inform and manage this usually disorganized process. The investigation of hillslope erosion and...
Assessment of undiscovered conventional oil and gas resources of six geologic provinces of China
Ronald R. Charpentier, Christopher J. Schenk, Michael E. Brownfield, Troy A. Cook, Timothy R. Klett, Janet K. Pitman, Richard M. Pollastro
2012, Fact Sheet 2012-3117
Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean volumes of undiscovered conventional petroleum resources in six geologic provinces of China at 14.9 billion barrels of oil, 87.6 trillion cubic feet of natural gas, and 1.4 billion barrels of natural-gas liquids....
Effects of earthworms on slopewash, surface runoff, and fine-litter transport on a humid-tropical forested hillslope in eastern Puerto Rico: Chapter G in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Matthew C. Larsen, Zhigang Liu Liu, Xiaoming Zou
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-G
Rainfall, slopewash (the erosion of soil particles), surface runoff, and fine-litter transport were measured in tropical wet forest on a hillslope in the Luquillo Experimental Forest, Puerto Rico, from February 1998 until April 2000. Slopewash data were collected using Gerlach troughs at eight plots, each 2 square meters in area....
Flood of August 11–16, 2010, in the South Skunk River Basin, central and southeast Iowa
Kimberlee K. Barnes, David A. Eash
2012, Open-File Report 2012-1202
Severe thunderstorm activity during August 8–11, 2010 in central and southeast Iowa resulted in major flooding from August 11–16, 2010, in the South Skunk River Basin. Rain gages at Ames and Story City recorded 96-hour rainfall amounts of 9.61 and 8.70 inches, respectively. The majority of the rainfall occurred during...
Land use, population dynamics, and land-cover change in eastern Puerto Rico: Chapter B in Water quality and landscape processes of four watersheds in eastern Puerto Rico
William A. Gould, Sebastián Martinuzzi, Isabel K. Pares-Ramos, Sheila F. Murphy, Robert F. Stallard
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-B
We assessed current and historic land use and land cover in the Luquillo Mountains and surrounding area in eastern Puerto Rico, including four small subwatersheds that are study watersheds of the U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets (WEBB) program. This region occupies an area of 1,616 square kilometers,...
Weathering, landscape equilibrium, and carbon in four watersheds in eastern Puerto Rico: Chapter H in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Robert F. Stallard
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-H
The U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets (WEBB) program research in eastern Puerto Rico involves a double pair-wise comparison of four montane river basins, two on granitic bedrock and two on fine-grained volcaniclastic bedrock; for each rock type, one is forested and the other is developed. A confounding...
Modeling the mesozoic-cenozoic structural evolution of east texas
Ofori N. Pearson, Elisabeth L. Rowan, John J. Miller
2012, Gulf Coast Assoc of Geological Societies Journal (1) 118-128
The U.S. Geological Survey (USGS) recently assessed the undiscovered technically recoverable oil and gas resources within Jurassic and Cretaceous strata of the onshore coastal plain and State waters of the U.S. Gulf Coast. Regional 2D seismic lines for key parts of the Gulf Coast basin were interpreted in order to...
Geologic framework for the national assessment of carbon dioxide storage resources: Powder River Basin, Wyoming, Montana, South Dakota, and Nebraska: Chapter B in Geologic framework for the national assessment of carbon dioxide storage resources
William H. Craddock, Ronald M. Drake II, John L. Mars, Matthew D. Merrill, Peter D. Warwick, Madalyn S. Blondes, Mayur A. Gosai, P.A. Freeman, Steven M. Cahan, Christina A. DeVera, Celeste D. Lohr
Peter D. Warwick, M.D. Corum, editor(s)
2012, Open-File Report 2012-1024-B
This report presents ten storage assessment units (SAUs) within the Powder River Basin of Wyoming, Montana, South Dakota, and Nebraska. The Powder River Basin contains a thick succession of sedimentary rocks that accumulated steadily throughout much of the Phanerozoic, and at least three stratigraphic packages contain strata that are suitable...
Weathering processes in the Rio Icacos and Rio Mameyes watersheds in Eastern Puerto Rico: Chapter I in Water quality and landscape processes of four watersheds in eastern Puerto Rico
Heather L. Buss, Arthur F. White
Sheila F. Murphy, Robert F. Stallard, editor(s)
2012, Professional Paper 1789-I
Streams draining watersheds of the two dominant lithologies (quartz diorite and volcaniclastic rock) in the Luquillo Experimental Forest of eastern Puerto Rico have very high fluxes of bedrock weathering products. The Río Blanco quartz diorite in the Icacos watershed and the Fajardo volcaniclastic rocks in the Mameyes watershed have some...
Coastal wetlands of Chesapeake Bay
Andrew H. Baldwin, Patrick J. Kangas, J. Patrick Megonigal, Matthew C. Perry, Dennis F. Whigham, Darold P. Batzer
Darold P. Batzer, Andrew H. Baldwin, editor(s)
2012, Book chapter, Wetland habitats of North America: Ecology and conservation concerns
Wetlands are prominent landscapes throughout North America. The general characteristics of wetlands are controversial, thus there has not been a systematic assessment of different types of wetlands in different parts of North America, or a compendium of the threats to their conservation. Wetland Habitats of North America adopts a geographic...
Uncertainty quantification for environmental models
Mary C. Hill, Dan Lu, Dmitri Kavetski, Martyn P. Clark, Ming Ye
2012, SIAM News (45)
Environmental models are used to evaluate the fate of fertilizers in agricultural settings (including soil denitrification), the degradation of hydrocarbons at spill sites, and water supply for people and ecosystems in small to large basins and cities—to mention but a few applications of these models. They also play a role...
Space-time models for a panzootic in bats, with a focus on the endangered Indiana bat
Wayne E. Thogmartin, R. Andrew King, Jennifer A. Szymanski, Lori Pruitt
2012, Journal of Wildlife Diseases (48) 876-887
Knowledge of current trends of quickly spreading infectious wildlife diseases is vital to efficient and effective management. We developed space-time mixed-effects logistic regressions to characterize a disease, white-nose syndrome (WNS), quickly spreading among endangered Indiana bats (Myotis sodalis) in eastern North America. Our goal was to calculate and map the...
Simulating potential structural and operational changes for Detroit Dam on the North Santiam River, Oregon, for downstream temperature management
Norman L. Buccola, Stewart A. Rounds, Annett B. Sullivan, John C. Risley
2012, Scientific Investigations Report 2012-5231
Detroit Dam was constructed in 1953 on the North Santiam River in western Oregon and resulted in the formation of Detroit Lake. With a full-pool storage volume of 455,100 acre-feet and a dam height of 463 feet, Detroit Lake is one of the largest and most important reservoirs in the...
Demonstration optimization analyses of pumping from selected Arapahoe aquifer municipal wells in the west-central Denver Basin, Colorado, 2010–2109
Edward R. Banta, Suzanne S. Paschke
2012, Scientific Investigations Report 2012-5140
Declining water levels caused by withdrawals of water from wells in the west-central part of the Denver Basin bedrock-aquifer system have raised concerns with respect to the ability of the aquifer system to sustain production. The Arapahoe aquifer in particular is heavily used in this area. Two optimization analyses were...
Effect of Feeding-Fasting Cycles on Oxygen Consumption and Bioenergetics of Yellow Perch
Steven R. Chipps, Travis W. Schaeffer, Daniel E. Spengler, Casey W. Schoenebeck, Michael L. Brown
2012, Transactions of the American Fisheries Society (141) 1480-1491
We measured growth and oxygen consumption of age-1 yellow perch Perca flavescenssubjected to ad libitum (control) or variable feeding cycles of 2 (i.e., 2 d of feed, 2 d of deprivation), 6, or 12 d for a 72-d period. Individual, female yellow perch (initial weight = 51.9 ± 0.9 g [mean...
Regional regression models of watershed suspended-sediment discharge for the eastern United States
David C. Roman, Richard M. Vogel, Gregory E. Schwarz
2012, Journal of Hydrologic Engineering (472-4723) 53-62
Estimates of mean annual watershed sediment discharge, derived from long-term measurements of suspended-sediment concentration and streamflow, often are not available at locations of interest. The goal of this study was to develop multivariate regression models to enable prediction of mean annual suspended-sediment discharge from available basin characteristics useful for most...
Precision of channel catfish catch estimates using hoop nets in larger Oklahoma reservoirs
David R. Stewart, James M. Long
2012, North American Journal of Fisheries Management (32) 1108-1112
Hoop nets are rapidly becoming the preferred gear type used to sample channel catfish Ictalurus punctatus, and many managers have reported that hoop nets effectively sample channel catfish in small impoundments (<200 ha). However, the utility and precision of this approach in larger impoundments have not been tested. We sought...
Holocene diatom flora and climate history of Medicine Lake, Northern California, USA
Scott W. Starratt
2012, Nova Hedwigia, Beiheft (141) 485-504
A 226-cm-long sediment core spanning the past ~ 11,400 years was recovered from Medicine Lake, on the Modoc Plateau in northeastern California. Diatom assemblages provide a record of lake level that is driven by local and regional climate changes and changes in basin morphology due to the activity of Medicine...
Developing accurate survey methods for estimating population sizes and trends of the critically endangered Nihoa Millerbird and Nihoa Finch.
P. Marcos Gorresen, Richard J. Camp, Kevin W. Brinck, Chris Farmer
2012, Technical Report HCSU-034
This report describes the results of a comparative study of bird survey methods undertaken for the purpose of improving assessments of the conservation status for the two endemic passerines on the Island of Nihoa—Nihoa Millerbird (Sylviidae: Acrocephalus familiaris kingi) and Nihoa Finch (Fringilidae: Telespiza ultima; also referred herein as millerbird...