The Central African Republic Diamond Database—A geodatabase of archival diamond occurrences and areas of recent artisanal and small-scale diamond mining
Jessica D. DeWitt, Peter G. Chirico, Sarah E. Bergstresser, Inga E. Clark
2018, Open-File Report 2018-1088
The alluvial diamond deposits of the Central African Republic (CAR) are mined almost exclusively by way of informal artisanal and small-scale mining (ASM) methods. ASM sites range in diameter from a few meters to 30 meters or more, and are typically excavated by crews of diggers using hand tools, sieves,...
The significance of dinoflagellates in the Miocene Choptank Formation beneath the Midlothian gravels in the southeastern Virginia Piedmont
Lucy E. Edwards, Robert E. Weems, Mark W. Carter, David Spears, David S. Powars
2018, Stratigraphy (15) 179-195
The Fall Line (formally "Tidewater Fall Line") separates the more resistant igneous, metamorphic, and consolidated sedimentary rocks of the Piedmont from the typically unconsolidated deposits of the Coastal Plain of Virginia. Widespread but now discontinuous patches of a deeply weathered sand and gravel are found west of the Fall Line,...
An underwater observation dataset for fish classification and fishery assessment
Erin L. McCann, Liling Li, Kevin Pangle, Nicholas S. Johnson, Jesse Eickholt
2018, Scientific Data (5) 1-8
Using Dual-Frequency Identification Sonar (DIDSON), fishery acoustic observation data was collected from the Ocqueoc River, a tributary of Lake Huron in northern Michigan, USA. Data were collected March through July 2013 and 2016 and included the identification, via technology or expert analysis, of eight fish species as they passed through...
Hydrodynamics of a tidally‐forced coral reef atoll
Rebecca H. Green, Ryan J. Lowe, Mark L. Buckley
2018, Journal of Geophysical Research C: Oceans (123) 7084-7101
The hydrodynamics of a tidally forced semi‐enclosed coral reef atoll (North Scott) at the edge of the continental shelf of northwestern Australia were investigated by combining field observations and numerical modeling. The observations revealed that the spring tidal range outside the atoll reaches 4 m, and as the water level drops...
Improving earthquake rupture forecasts using California as a guide
Edward H. Field, Working Group on California Earthquake Probabilities
2018, Seismological Research Letters (89) 2337-2346
This article discusses ways in which earthquake rupture forecast models might be improved. Because changes are most easily described in the context of specific models, the third Uniform California Earthquake Rupture Forecast (UCERF3) and its presumed successor, UCERF4, is used as a basis for discussion. Virtually all of the issues...
Downhole log evidence for the coexistence of structure II gas hydrate and free gas below the bottom simulating reflector in the South China Sea
Jin Qian, Xiujuan Wang, Timothy S. Collett, Yiqun Guo, Dongju Kang, Jiapeng Jin
2018, Marine and Petroleum Geology (98) 662-674
Stratigraphic layered pore-filling gas hydrates are identified above the bottom simulating reflector (BSR) using the well log and core data acquired at Sites W11 and W17 during the third gas hydrate drilling expedition conducted by China's Geological Survey/Guangzhou Marine Geological Survey (GMGS3) in the South China Sea. A seismic profile near Site W17, reveal the presence...
Igneous and detrital zircon U-Pb and Lu-Hf geochronology of the late Meso- to Neoproterozoic northwest Botswana rift: Maximum depositional age and provenance of the Ghanzi Group, Kalahari Copperbelt, Botswana and Namibia
Wesley S Hall, Murray Hitzman, Yvette D. Kuiper, Andrew R C Kylander-Clark, Christopher S. Holm-Denoma, Richard J. Moscati, Piret Plink-Bjorklund, Stephen M Enders
2018, Precambrian Research (318) 133-155
New igneous and detrital zircon laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) U-Pb geochronology and Lu-Hf isotopic data are presented for the Mesoproterozoic Kgwebe Formation and the unconformably overlying Ghanzi Group in northwestern Botswana. The Makgabana Hills porphyritic rhyolite flow from...
Diet and condition of age‐0 Scaphirhynchus Sturgeon: Implications for shallow‐water habitat restoration
A. P. Civiello, N. J. C. Gosch, T. R. Gemeinhardt, M. L. Miller, J. L. Bonneau, Kimberly Chojnacki, Aaron J. Delonay, James M. Long
2018, North American Journal of Fisheries Management (38) 1324-1338
Insufficient food during early life could limit the population growth of endangered Pallid Sturgeon Scaphirhynchus albus in the lower Missouri River. Shallow‐water habitat restoration is intended to provide nursery benefits, including food, for young sturgeon, but the effect of shallow‐water habitat on their diet is unknown. Age‐0 Pallid Sturgeon are rare, providing...
Mount St. Helens retrospective: Lessons learned since 1980 and remaining challenges
Daniel Dzurisin
2018, Frontiers in Earth Science (6) 1-24
Since awakening from a 123-year repose in 1980, Mount St. Helens has provided an opportunity to study changes in crustal magma storage at an active arc volcano—a process of fundamental importance to eruption forecasting and hazards mitigation. There has been considerable progress, but important questions remain unanswered. Was the 1980...
Thiamine deficiency in fishes: Causes, consequences, and potential solutions
Avril M. Harder, William R. Ardren, Allison N. Evans, Matthew H. Futia, Clifford E. Kraft, J. Ellen Marsden, Catherine A. Richter, Jacques Rinchard, Donald E. Tillitt, Mark R. Christie
Mark R. Christie, editor(s)
2018, Reviews in Fish Biology and Fisheries (28) 865-886
Thiamine deficiency complex (TDC) is a disorder resulting from the inability to acquire or retain thiamine (vitamin B1) and has been documented in organisms in aquatic ecosystems ranging from the Baltic Sea to the Laurentian Great Lakes. The biological mechanisms leading to TDC emergence may vary among systems, but in...
Improving confidence by embracing uncertainty: A meta-analysis of U.S. hunting values for benefit transfer
Christopher Huber, James Meldrum, Leslie Richardson
2018, Ecosystem Services (33) 225-236
Recreational hunting in the United States has traditional and cultural importance, and generates substantial economic benefits to individual hunters themselves. This paper conducts a meta-analysis of existing nonmarket valuation estimates for hunting in the United States to explore sources and implications of variation and uncertainty in these estimates. A multi-level...
Machine learning for ecosystem services
Simon Willcock, Javier Martinez-Lopez, Danny A.P. Hooftman, Kenneth J. Bagstad, Stefano Balbi, Alessia Marzo, Carlo Prato, Saverio Sciandrello, Giovanni Signorello, Brian Voigt, Ferdinando Villa, James M. Bullock, Ioannis Athanasiadis
2018, Ecosystem Services (33) 165-174
Recent developments in machine learning have expanded data-driven modelling (DDM) capabilities, allowing artificial intelligence to infer the behaviour of a system by computing and exploiting correlations between observed variables within it. Machine learning algorithms may enable the use of increasingly available ‘big data’ and assist applying ecosystem service models across...
Historical eruptions and hazards at Bogoslof volcano, Alaska
Christopher F. Waythomas, Cheryl E. Cameron
2018, Scientific Investigations Report 2018-5085
Bogoslof volcano is a submarine volcano in the southernBering Sea (53.9272°N, 168.0344°W), located 100 kilometers(km) west of Dutch Harbor/Unalaska, and 40 km northof Umnak Island. The volcano has a relatively long history ofscientific investigation and several of its historical eruptionshave been documented during brief visits to the area since thelate...
Powerful turbidity currents driven by dense basal layers
C. K. Paull, P. J. Talling, Katherine L. Maier, Daniel Parsons, Jingping Xu, D. W. Caress, R. Gwiazda, E. Lundsten, K. Anderson, James P. Barry, M. Chaffey, T. O’Reilly, Kurt J. Rosenberger, Jenny Gales, Brian Kieft, Mary McGann, Samantha E. Simmons, M. McCann, Esther J. Sumner, M. A. Clare, M. J. Cartigny
2018, Nature Communications (9)
Seafloor sediment flows (turbidity currents) are among the volumetrically most important yet least documented sediment transport processes on Earth. A scarcity of direct observations means that basic characteristics, such as whether flows are entirely dilute or driven by a dense basal layer, remain equivocal. Here we present the most detailed...
Assessment of environmental flows in the middle Verde River watershed, Arizona
Bruce Gungle, Nicholas V. Paretti
2018, Fact Sheet 2018-3062
This report summarizes analyses of middle Verde River watershed environmental flows detailed in U.S. Geological Survey Scientific Investigations Report 2017-5100, “Preliminary synthesis and assessment of environmental flows in the middle Verde River watershed, Arizona," by N.V. Paretti, A.M.D. Brasher, S.L. Pearlstein, D.M. Skow, B. Gungle, and...
An intercomparison of oceanic methane and nitrous oxide measurements
Samuel Wilson, Hermann Bange, Damian Arevalo-Martinez, Jonathan Barnes, Alberto V. Borges, Ian Brown, John Bullister, Macarena Burgos, David Capelle, Michael Casso, Mercedes de la Paz, Laura Farias, Lindsay Fenwick, Sara Ferron, Gerardo Garcia, MIchael Glockzin, David Karl, Annette Kock, Sarah Laperriere, Cliff S. Law, Cara Manning, Andrew Marriner, Jukka-Pekka Myllykangas, John Pohlman, Andrew Rees, Allison Santoro, Philippe Tortll, Robert C. Upstill-Goddard, David Wisegarver, Gui-Ling Zhang, Gregor Rehder
2018, Biogeosciences (15) 5801-5907
Large-scale climatic forcing is impacting oceanic biogeochemical cycles and is expected to influence the water-column distribution of trace gases, including methane and nitrous oxide. Our ability as a scientific community to evaluate changes in the water-column inventories of methane and nitrous oxide depends largely on our capacity to obtain robust...
Diatom floras in lakes in the Ruby Mountains and East Humboldt Range, Nevada, USA: A tool for assessing high-elevation climatic variability
Scott W. Starratt
2018, Book chapter, Nova Hedwigia
Local conditions, including lake size, depth, bathymetric profile, watershed characteristics, and timing and extent of ice cover determine the characteristics of diatom floras, and how those assemblages respond to short and long-term changes in climate. The diatom assemblages from fourteen sediment samples collected from marginal and profundal zones of seven...
VS30 at three strong-motion recording stations in Napa and Solano Counties, California — Lovall Valley Road, Broadway Street and Sereno Drive in Vallejo, and Vallejo Fire Station — Calculations determined from S-wave refraction tomography and multichannel analysis of surface waves (Rayleigh and Love)
Joanne H. Chan, Rufus D. Catchings, Mark R. Goldman, Coyn J. Criley
2018, Open-File Report 2018-1162
The August 24, 2014, moment magnitude (Mw) 6.0 South Napa earthquake caused an estimated $400 million in structural damage to the City of Napa, California. In 2015, we acquired high-resolution P- and S-wave seismic data near three strong-motion recording stations in Napa and Solano Counties where high peak ground accelerations...
VS30 at three strong-motion recording stations in Napa and Napa County, California — Main Street in downtown Napa, Napa fire station number 3, and Kreuzer Lane — Calculations determined from s-wave refraction tomography and multichannel analysis of surface waves (Rayleigh and Love)
Joanne H. Chan, Rufus D. Catchings, Mark R. Goldman, Coyn J. Criley
2018, Open-File Report 2018-1161
The August 24, 2014, moment magnitude (Mw) 6.0 South Napa earthquake caused an estimated $400 million in structural damage to the City of Napa, California. In 2015, we acquired high-resolution P- and S-wave seismic data near three strong-motion recording stations in Napa County where high peak ground accelerations (PGAs) were...
Investigating the mixing efficiencies of liquid-to-liquid chemical injection manifolds for aquatic invasive species management
Thomas J. Zolper, Aaron R. Cupp, David L. Smith
2018, Journal of Fluids Engineering (141) 1-14
Aquatic invasive species (AIS) have spread throughout the United States via major rivers and tributaries. Locks and dams positioned along affected waterways, specifically lock chambers, are being evaluated as potential management sites to prevent further expansion into new areas. Recent research has shown that infusion of chemicals (e.g., carbon dioxide)...
Effects of large-scale wetland loss on network connectivity of the Rainwater Basin, Nebraska
Bram H. F. Verheijen, Dana M. Varner, David A. Haukos
2018, Landscape Ecology (33) 1939-1951
ContextThe Rainwater Basin region in south-central Nebraska supports a complex network of spatially-isolated wetlands that harbor diverse floral and faunal communities. Since European settlement, many wetlands have been lost from the network, which has increased distances among remaining wetlands. As a result, populations of wildlife species with limited dispersal capabilities...
Artelle et al. (2018) miss the science underlying North American wildlife management
Jonathan R. Mawdsley, John F. Organ, Daniel J. Decker, Ann Forstchen, Ronald J. Regan, Shawn J. Riley, Mark S. Boyce, John E. Mcdonald Jr., Chris Dwyer, Shane P. Mahoney
2018, Science Advances (4) 1-2
Artelle et al. (2018) conclude that “hallmarks of science” are largely missing from North American wildlife management based on a desk review of selected hunting management plans and related documents found through Internet searches and email requests to state and provincial wildlife agencies. We highlight three fundamental problems that compromise the...
Impact of sylvatic plague vaccine on non-target small rodents in grassland ecosystems
Gebbiena M. Bron, Katherine L. D. Richgels, Samuel. Michael D., Julia E. Poje, Faye Lorenzsonn, Jonathan P. Matteson, Jesse T. Boulerice, Jorge E. Osorio, Tonie E. Rocke
2018, EcoHealth (15) 555-565
Oral vaccination is an emerging management strategy to reduce the prevalence of high impact infectious diseases within wild animal populations. Plague is a flea-borne zoonosis of rodents that often decimates prairie dog (Cynomys spp.) colonies in the western USA. Recently, an oral sylvatic plague vaccine (SPV) was developed to...
Embryonic effects of an environmentally relevant PCB mixture in the domestic chicken
Mary Ann Ottinger, Emma T. Lavoie, Mary E. B. Bohannon, Allegra M. Marcel, Anna E. Tschiffely, Kara B. Duffy, Moira A. McKernan, Nichola Thompson, H. Kasen Whitehouse, Kimya Davani, Marci Strauss, Donald E. Tillitt, Joshua Lipton, Karen M. Dean
2018, Environmental Toxicology and Chemistry (37) 2513-2522
Studies were conducted to develop methods to assess the effects of a complex mixture of polychlorinated biphenyls (PCBs) in the domestic chicken (Gallus domesticus). Treatments were administered by egg injection to compare embryonic effects of an environmentally relevant PCB congener mixture in the domestic chicken over a range of doses....
Chronic toxicity of 4-nonylphenol to two unionid mussels in water-only exposures
Chris D. Ivey, Ning Wang, David Alvarez, Edward J. Hammer, Candice R. Bauer
2018, Bulletin of Environmental Contamination and Toxicology (101) 423-427
Limited studies indicate that mussels are generally insensitive to organic chemicals; however, these studies were conducted in acute or short-term exposures, and little is known about the chronic sensitivity of mussels to organic chemicals. We evaluated the chronic (28 days) toxicity of 4-nonylphenol (4-NP) to two commonly tested species of mussels:...