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Seismic site characterization with shear wave (SH) reflection and refraction methods Seismic site characterization with shear wave (SH) reflection and refraction methods
Reflection and critically refracted seismic methods use traveltime measurements of body waves propagating between a source and a series of receivers on the ground surface to calculate subsurface velocities. Body wave energy is refracted or reflected at boundaries where there is a change in seismic impedance, defined as the product of material density and seismic velocity. This article...
Authors
James A. Hunter, Heather L. Crow, William J. Stephenson, Andre J.-M. Pugin, Robert Williams, James B. Harris, Jackson K. Odum, Edward W Woolery
Evolution and taxonomy of the Paleogene calcareous nannofossil genus Hornibrookina Evolution and taxonomy of the Paleogene calcareous nannofossil genus Hornibrookina
The genus Hornibrookina consists of enigmatic calcareous nannofossils that first appeared shortly after the K-Pg mass extinction. Due to their relative paucity in most published sections, specimens of this genus have not been previously studied in detail and their paleobiogeographic preferences and evolutionary history have been poorly understood. Biostratigraphic and morphometric...
Authors
Jean Self-Trail, David K. Watkins, James J. Pospichal, Ellen Seefelt
Analysis of ocean dynamics during the impact of Hurricane Matthew using ocean-atmosphere coupling Analysis of ocean dynamics during the impact of Hurricane Matthew using ocean-atmosphere coupling
The main goal of this investigation is to improve the understanding of ocean-atmosphere coupling during hurricanes. The present work involves the integration of the ocean-atmosphere coupled components of the Coupled Ocean-Atmosphere-Wave-Sediment Transport Modeling System in the Very Short Term Prediction System (SisPI). Three experiments are performed: First, using a dynamic sea surface
Authors
Liset Vazquez Proveyer, Maibys Sierra Lorenzo, Roberto Carlos Cruz Rodriguez, John C. Warner
A novel gonadotropic microsporidian parasite (Microsporidium clinchi n. sp.) infecting a declining population of pheasantshell mussels (Actinonaias pectorosa) (Unioinidae) from the Clinch River, USA A novel gonadotropic microsporidian parasite (Microsporidium clinchi n. sp.) infecting a declining population of pheasantshell mussels (Actinonaias pectorosa) (Unioinidae) from the Clinch River, USA
Freshwater mussels of the order Unionida are among the most endangered animal groups globally, but the causes of their population decline are often enigmatic, with little known about the role of disease. In 2018, we collected wild adult pheasantshell (Actinonaias pectorosa) and mucket (Actinonaias ligamentina) during an epidemiologic survey investigating an ongoing mussel mass mortality...
Authors
Susan Knowles, Eric M. Leis, Jordan C. Richard, Rebecca A. Cole, Rose E. Agbalog, Joel G. Putnam, Tony L. Goldberg, Diane L. Waller
Caretta caretta (Loggerhead Sea Turtle) nesting exchange Caretta caretta (Loggerhead Sea Turtle) nesting exchange
The Northwest Atlantic population of Loggerhead Sea Turtles (Caretta caretta) is one of the largest C. caretta populations in the world and is listed as threatened. This population was divided into five genetically distinct subpopulations, including the Northern Gulf of Mexico (NGoM) subpopulation (Shamblin et al. 2017 Mar. Bio. 164:138). Across the NGoM, the majority of C. caretta...
Authors
Margaret Lamont, Jennifer S. Walker, Donna J. Shaver
Extensive droughts in the conterminous United States during multiple centuries Extensive droughts in the conterminous United States during multiple centuries
Extensive and severe droughts have substantial effects on water supplies, agriculture, and aquatic ecosystems. To better understand these droughts, we used tree-ring-based reconstructions of the Palmer drought severity index (PDSI) for the period 1475–2017 to examine droughts that covered at least 33% of the conterminous United States (CONUS). We identified 37 spatially extensive drought...
Authors
Gregory J. McCabe, David M. Wolock
An assessment of uncertainties in VS profiles obtained from microtremor observations in the phased 2018 COSMOS blind trials An assessment of uncertainties in VS profiles obtained from microtremor observations in the phased 2018 COSMOS blind trials
Site response is a critical consideration when assessing earthquake hazards. Site characterization is key to understanding site effects as influenced by seismic site conditions of the local geology. Thus, a number of geophysical site characterization methods were developed to meet the demand for accurate and cost-effective results. As a consequence, a number of studies have been...
Authors
Michael W. Asten, Alan Yong, Sebastiano Foti, Koichi Hayashi, Antony J. Martin, William J. Stephenson, John F. Cassidy, Jacie Coleman, Robert L. Nigbor, Silvia Castellaro, Kosuke Chimoto, Ikuo Cho, Cecile Cornou, Takumi Hayashida, Manuel Hobiger, Chun-Hsiang Kuo, Albert Macau, E. Diego Mercerat, Sheri Molnar, Passakorn Pananont, Marco Pilz, Nakhorn Poovarodom, Esteban Saez, Marc Wathelet, Hiroaki Yamanaka, Toshiaki Yokoi, Don Zhao
Impact of spectral resolution on quantifying cyanobacteria in lakes and reservoirs: A machine-learning assessment Impact of spectral resolution on quantifying cyanobacteria in lakes and reservoirs: A machine-learning assessment
Cyanobacterial harmful algal blooms are an increasing threat to coastal and inland waters. These blooms can be detected using optical radiometers due to the presence of phycocyanin (PC) pigments. The spectral resolution of best-available multispectral sensors limits their ability to diagnostically detect PC in the presence of other photosynthetic pigments. To assess the role of spectral...
Authors
Kiana Zolfaghari, Nima Pahlevan, Caren Binding, Daniela Gurlin, Stefan G.H. Simis, Antonio Ruiz Verdu, Lin Li, Christopher J. Crawford, Andrea VanderWoude, Reagan Errera, Arthur Zastepa, Claude R. Duguay
An 11,300 yr record of paleoclimatology and paleoceanography of the central California coast in a gravity core from Pioneer Seamount An 11,300 yr record of paleoclimatology and paleoceanography of the central California coast in a gravity core from Pioneer Seamount
Diatom, pollen, silicoflagellate, and biogenic opal analyses from a 155 cm-long gravity core from Pioneer Seamount, offshore Santa Cruz, California (PS1410-06 GC, latitude 37.3°N, longitude 123.4°W, water depth 2165 m) are compiled for the last ~11,300 years and compared with those of ODP 1019 and TN062-O550 from northern California. The relative abundance record of the subtropical...
Authors
John A. Barron, Jason A. Addison, Linda E. Heusser, David Bukry, Valerie Evelyn Schwartz, Amy Wagner
Breaking up is hard to do: Magmatism during oceanic arc breakup, subduction reversal, and cessation Breaking up is hard to do: Magmatism during oceanic arc breakup, subduction reversal, and cessation
The formerly continuous Vitiaz Arc broke into its Vanuatu and Fijian portions during a reversal of subduction polarity in the Miocene. Basaltic volcanism in Fiji that accompanied the breakup ranged from shoshonitic to low-K and boninitic with increasing distance from the broken edge of the arc that, presumably, marks the broken edge of the slab. The Sr-Pb-Nd isotope ratios of the slab...
Authors
James F. Gill, Erin Todd, Kaj Hoernle, Folkmar Hauff, Alison Ann Price, Matthew G. Jackson
Broad-scale geographic and temporal assessment of northern long-eared bat (Myotis septentrionalis) maternity colony-landscape association Broad-scale geographic and temporal assessment of northern long-eared bat (Myotis septentrionalis) maternity colony-landscape association
As the federally threatened northern long-eared bat Myotis septentrionalis continues to decline due to white-nose syndrome (WNS) impacts, the application of effective conservation measures is needed but often hindered by the lack of ecological data. To date, recommended management practices have been adopted in part from other federally listed sympatric species such as the endangered...
Authors
Katherine M. Gorman, Sabrina M. Deeley, Elaine L. Barr, Samuel R. Freeze, Nicholas Kalen, Michael S. Muthersbaugh, W. Mark Ford
Characteristics of day-roosts used by the Northern Long-eared Bat (Myotis septentrionalis) in coastal New York Characteristics of day-roosts used by the Northern Long-eared Bat (Myotis septentrionalis) in coastal New York
In North America, Myotis septentrionalis (Northern Long-eared Bat) has experienced precipitous declines from white-nose syndrome. As these bats become rare and difficult to capture, additional day-roost assessments to inform management may fill gaps in our understanding, particularly in habitats and regions where such roosts have never been surveyed. Over 2 summers, we radio-tracked 16...
Authors
Katherine M. Gorman, Elaine L. Barr, Tomas Nocera, W. Mark Ford