From 2000 to 2004, over 10,000 seabirds, primarily Herring Gulls (Larus argentatus), died from an undetermined cause in the Blekinge archipelago in southeastern Sweden. In June 2004, 24 affected Herring Gulls were examined clinically, killed humanely, and 23 were examined by necropsy. Seven and 10 unaffected Herring Gulls collected from a local landfill site and from Iceland, respectively, served as controls. All affected birds showed similar neurologic signs, ranging from mild incoordination and weakness to severe flaccid paralysis of legs and wings, but generally were alert and responsive. All affected gulls were in normal nutritional condition, but were dehydrated and had empty stomachs. No gross or microscopic lesions, and no bacterial or viral pathogens were identified. Type C botulinum toxin was detected in the sera of 11 of 16 (69%) affected gulls by mouse inoculation. Type C botulism was the proximate cause of disease in 2004. Sera from 31% of birds tested from outbreaks in 2000 to 2003 also had detectable type C botulinum toxin by mouse inoculation. No large-scale botulism outbreak has been documented previously in this area. The source of toxin, initiating conditions, and thus, the ultimate cause of this outbreak are not known. This epidemic might signal environmental change in the Baltic Sea.
","language":"English","publisher":"Wildlife Disease Association","doi":"10.7589/0090-3558-43.3.327","issn":"00903558","usgsCitation":"Neimanis, A., Gavier-Widen, D., Leighton, F., Bollinger, T., Rocke, T.E., and Morner, T., 2007, An outbreak of type C botulism in Herring Gulls (Larus argentatus) in Southeastern Sweden: Journal of Wildlife Diseases, v. 43, no. 3, p. 327-336, https://doi.org/10.7589/0090-3558-43.3.327.","productDescription":"10 p.","startPage":"327","endPage":"336","numberOfPages":"10","costCenters":[{"id":456,"text":"National Wildlife Health Center","active":true,"usgs":true}],"links":[{"id":477347,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"http://www.bioone.org/doi/10.7589/0090-3558-43.3.327","text":"External Repository"},{"id":238890,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"43","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059eaa8e4b0c8380cd489d2","contributors":{"authors":[{"text":"Neimanis, A.","contributorId":85770,"corporation":false,"usgs":true,"family":"Neimanis","given":"A.","email":"","affiliations":[],"preferred":false,"id":428621,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gavier-Widen, D.","contributorId":14635,"corporation":false,"usgs":true,"family":"Gavier-Widen","given":"D.","affiliations":[],"preferred":false,"id":428618,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Leighton, F.","contributorId":85771,"corporation":false,"usgs":true,"family":"Leighton","given":"F.","email":"","affiliations":[],"preferred":false,"id":428622,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Bollinger, T.","contributorId":11978,"corporation":false,"usgs":true,"family":"Bollinger","given":"T.","email":"","affiliations":[],"preferred":false,"id":428617,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Rocke, Tonie E. 0000-0003-3933-1563 trocke@usgs.gov","orcid":"https://orcid.org/0000-0003-3933-1563","contributorId":2665,"corporation":false,"usgs":true,"family":"Rocke","given":"Tonie","email":"trocke@usgs.gov","middleInitial":"E.","affiliations":[{"id":456,"text":"National Wildlife Health Center","active":true,"usgs":true}],"preferred":true,"id":428620,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Morner, T.","contributorId":35944,"corporation":false,"usgs":true,"family":"Morner","given":"T.","affiliations":[],"preferred":false,"id":428619,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70030776,"text":"70030776 - 2007 - Diverse dinosaur-dominated ichnofaunas from the Potomac Group (Lower Cretaceous) Maryland","interactions":[],"lastModifiedDate":"2018-03-06T14:51:51","indexId":"70030776","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1965,"text":"Ichnos: An International Journal for Plant and Animal Traces","onlineIssn":"1563-5236","printIssn":"1042-0940","active":true,"publicationSubtype":{"id":10}},"title":"Diverse dinosaur-dominated ichnofaunas from the Potomac Group (Lower Cretaceous) Maryland","docAbstract":"Until recently fossil footprints were virtually unknown from the Cretaceous of the eastern United States. The discovery of about 300 footprints in iron-rich siliciclastic facies of the Patuxent Formation (Potomac Group) of Aptian age is undoubtedly one of the most significant Early Cretaceous track discoveries since the Paluxy track discoveries in Texas in the 1930s. The Patuxent tracks include theropod, sauropod, ankylosaur and ornithopod dinosaur footprints, pterosaur tracks, and miscellaneous mammal and other vertebrate ichnites that collectively suggest a diversity of about 14 morphotypes. This is about twice the previous maximum estimate for any known Early Cretaceous vertebrate ichnofauna. Among the more distinctive forms are excellent examples of hypsilophodontid tracks and a surprisingly large mammal footprint. A remarkable feature of the Patuxent track assemblage is the high proportion of small tracks indicative of hatchlings, independently verified by the discovery of a hatchling-sized dinosaur. Such evidence suggests the proximity of nest sites. The preservation of such small tracks is very rare in the Cretaceous track record, and indeed throughout most of the Mesozoic.
This unusual preservation not only provides us with a window into a diverse Early Cretaceous ecosystem, but it also suggests the potential of such facies to provide ichnological bonanzas. A remarkable feature of the assemblage is that it consists largely of reworked nodules and clasts that may have previously been reworked within the Patuxent Formation. Such unusual contexts of preservation should provide intriguing research opportunities for sedimentologists interested in the diagenesis and taphonomy of a unique track-bearing facies.
","language":"English","publisher":"Taylor & Francis","doi":"10.1080/10420940601049404","usgsCitation":"Stanford, R., Lockley, M.G., and Weems, R.E., 2007, Diverse dinosaur-dominated ichnofaunas from the Potomac Group (Lower Cretaceous) Maryland: Ichnos: An International Journal for Plant and Animal Traces, v. 14, no. 3-4, p. 155-173, https://doi.org/10.1080/10420940601049404.","productDescription":"19 p.","startPage":"155","endPage":"173","costCenters":[],"links":[{"id":238889,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Maryland","volume":"14","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a034be4b0c8380cd503f1","contributors":{"authors":[{"text":"Stanford, Ray","contributorId":12240,"corporation":false,"usgs":false,"family":"Stanford","given":"Ray","email":"","affiliations":[],"preferred":false,"id":428614,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lockley, Martin G.","contributorId":22428,"corporation":false,"usgs":false,"family":"Lockley","given":"Martin","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":428616,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Weems, Robert E. 0000-0002-1907-7804 rweems@usgs.gov","orcid":"https://orcid.org/0000-0002-1907-7804","contributorId":2663,"corporation":false,"usgs":true,"family":"Weems","given":"Robert","email":"rweems@usgs.gov","middleInitial":"E.","affiliations":[{"id":243,"text":"Eastern Geology and Paleoclimate Science Center","active":true,"usgs":true},{"id":40020,"text":"Florence Bascom Geoscience Center","active":true,"usgs":true}],"preferred":true,"id":428615,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030773,"text":"70030773 - 2007 - Numerical investigation of implementation of air-earth boundary by acoustic-elastic boundary approach","interactions":[],"lastModifiedDate":"2012-03-12T17:21:18","indexId":"70030773","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1808,"text":"Geophysics","active":true,"publicationSubtype":{"id":10}},"title":"Numerical investigation of implementation of air-earth boundary by acoustic-elastic boundary approach","docAbstract":"The need for incorporating the traction-free condition at the air-earth boundary for finite-difference modeling of seismic wave propagation has been discussed widely. A new implementation has been developed for simulating elastic wave propagation in which the free-surface condition is replaced by an explicit acoustic-elastic boundary. Detailed comparisons of seismograms with different implementations for the air-earth boundary were undertaken using the (2,2) (the finite-difference operators are second order in time and space) and the (2,6) (second order in time and sixth order in space) standard staggered-grid (SSG) schemes. Methods used in these comparisons to define the air-earth boundary included the stress image method (SIM), the heterogeneous approach, the scheme of modifying material properties based on transversely isotropic medium approach, the acoustic-elastic boundary approach, and an analytical approach. The method proposed achieves the same or higher accuracy of modeled body waves relative to the SIM. Rayleigh waves calculated using the explicit acoustic-elastic boundary approach differ slightly from those calculated using the SIM. Numerical results indicate that when using the (2,2) SSG scheme for SIM and our new method, a spatial step of 16 points per minimum wavelength is sufficient to achieve 90% accuracy; 32 points per minimum wavelength achieves 95% accuracy in modeled Rayleigh waves. When using the (2,6) SSG scheme for the two methods, a spatial step of eight points per minimum wavelength achieves 95% accuracy in modeled Rayleigh waves. Our proposed method is physically reasonable and, based on dispersive analysis of simulated seismographs from a layered half-space model, is highly accurate. As a bonus, our proposed method is easy to program and slightly faster than the SIM. ?? 2007 Society of Exploration Geophysicists.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geophysics","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1190/1.2753831","issn":"00168033","usgsCitation":"Xu, Y., Xia, J., and Miller, R., 2007, Numerical investigation of implementation of air-earth boundary by acoustic-elastic boundary approach: Geophysics, v. 72, no. 5, https://doi.org/10.1190/1.2753831.","costCenters":[],"links":[{"id":211524,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1190/1.2753831"},{"id":238825,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"72","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a68ece4b0c8380cd73a86","contributors":{"authors":[{"text":"Xu, Y.","contributorId":47816,"corporation":false,"usgs":true,"family":"Xu","given":"Y.","email":"","affiliations":[],"preferred":false,"id":428603,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Xia, J.","contributorId":63513,"corporation":false,"usgs":true,"family":"Xia","given":"J.","email":"","affiliations":[],"preferred":false,"id":428604,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Miller, R. D.","contributorId":92693,"corporation":false,"usgs":true,"family":"Miller","given":"R. D.","affiliations":[],"preferred":false,"id":428605,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030772,"text":"70030772 - 2007 - Food web structure in exotic and native mangroves: A Hawaii-Puerto Rico comparison","interactions":[],"lastModifiedDate":"2012-03-12T17:21:17","indexId":"70030772","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2932,"text":"Oecologia","active":true,"publicationSubtype":{"id":10}},"title":"Food web structure in exotic and native mangroves: A Hawaii-Puerto Rico comparison","docAbstract":"Plant invasions can fundamentally alter detrital inputs and the structure of detritus-based food webs. We examined the detrital pathways in mangrove food webs in native (Puerto Rican) and introduced (Hawaiian) Rhizophora mangle forests using a dual isotope approach and a mixing model. Based on trophic-level fractionation of 0-1??? for ?? 13C and 2-3??? for ?? 15N, among the invertebrates, only nematodes, oligochaetes, and nereid polychaetes from native mangroves exhibited stable isotopes consistent with a mangrove-derived diet. Certain fauna, in particular tubificid oligochaetes, had ?? 13C values consistent with the consumption of mangrove leaves, but they were depleted in 15N, suggesting their primary nitrogen source was low in 15N, and was possibly N 2-fixing bacteria. In introduced mangroves, all feeding groups appeared to rely heavily on non-mangrove sources, especially phytoplankton inputs. Mixing model results and discriminant analysis showed clear separation of introduced and native mangrove sites based on differential food source utilization within feeding groups, with stronger and more diverse use of benthic foods observed in native forests. Observed differences between native and invasive mangrove food webs may be due to Hawaiian detritivores being poorly adapted to utilizing the tannin-rich, nitrogen-poor mangrove detritus. In addition, differential utilization of mangrove detritus between native and introduced mangroves may be a consequence of forest age. We postulate that increasing mangrove forest age may promote diversification of bacterial food webs important in N and S cycling. Our results also suggest a potentially important role for sulfur bacteria in supporting the most abundant infaunal consumers, nematodes, in the most mature systems. ?? 2007 Springer-Verlag.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Oecologia","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s00442-007-0751-x","issn":"00298549","usgsCitation":"Demopoulos, A.W., Fry, B., and Smith, C.R., 2007, Food web structure in exotic and native mangroves: A Hawaii-Puerto Rico comparison: Oecologia, v. 153, no. 3, p. 675-686, https://doi.org/10.1007/s00442-007-0751-x.","startPage":"675","endPage":"686","numberOfPages":"12","costCenters":[],"links":[{"id":211523,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s00442-007-0751-x"},{"id":238824,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"153","issue":"3","noUsgsAuthors":false,"publicationDate":"2007-06-22","publicationStatus":"PW","scienceBaseUri":"505a12e7e4b0c8380cd5443b","contributors":{"authors":[{"text":"Demopoulos, A. W.J.","contributorId":50638,"corporation":false,"usgs":true,"family":"Demopoulos","given":"A.","middleInitial":"W.J.","affiliations":[],"preferred":false,"id":428601,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fry, B.","contributorId":52694,"corporation":false,"usgs":true,"family":"Fry","given":"B.","email":"","affiliations":[],"preferred":false,"id":428602,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Smith, C. R.","contributorId":32876,"corporation":false,"usgs":true,"family":"Smith","given":"C.","middleInitial":"R.","affiliations":[],"preferred":false,"id":428600,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030764,"text":"70030764 - 2007 - Aqueous exposure to 4-nonylphenol and 17β-estradiol increases stress sensitivity and disrupts ion regulatory ability of juvenile atlantic salmon","interactions":[],"lastModifiedDate":"2015-04-06T13:03:21","indexId":"70030764","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1571,"text":"Environmental Toxicology and Chemistry","active":true,"publicationSubtype":{"id":10}},"title":"Aqueous exposure to 4-nonylphenol and 17β-estradiol increases stress sensitivity and disrupts ion regulatory ability of juvenile atlantic salmon","docAbstract":"Population declines of wild Atlantic salmon have been attributed to an array of anthropogenic disturbances, including dams, commercial and recreational fishing, habitat loss, and pollution. Environmental contaminants in particular, can act as environmental stressors on fish, typically causing disruption of ion homeostasis due to their close association with the aquatic environment. To examine the effects of the xenoestrogen 4-nonylphenol (NP) or 17β-estradiol (E2) on stress sensitivity and ion regulation, we exposed juvenile Atlantic salmon continuously for 21 d to either 10 or 100 μg/L NP (NP-L or NP-H), 2 μg/L E2 (positive control), or vehicle control during the parr-smolt transformation in April. After treatment, fish were sampled in freshwater (FW), transferred to 30‰ seawater (SW) for 24 h, or subjected to a handling stress. Estradiol and NP-H increased plasma vitellogenin in males and females, and E2 increased gonadosomatic index only in males. In FW, E2 reduced sodium potassium–activated adenosine triphosphatase activity as well as plasma levels of growth hormone, insulin-like growth factor I, and triiodothyronine. Both E2 and NP-H reduced plasma sodium in FW and increased plasma chloride in SW. Plasma Cortisol levels pre- and poststressor were significantly elevated by all treatments relative to controls, but only E2 increased plasma glucose before and after the stressor. These results indicate that exposure of anadromous salmonids to environmental estrogens heightens sensitivity to external stressors, impairs ion regulation in both FW and SW, and disrupts endocrine pathways critical for smolt development.
","language":"English","publisher":"Wiley","doi":"10.1897/06-451R1.1","issn":"07307268","usgsCitation":"Lerner, D.T., Bjornsson, B.T., and McCormick, S., 2007, Aqueous exposure to 4-nonylphenol and 17β-estradiol increases stress sensitivity and disrupts ion regulatory ability of juvenile atlantic salmon: Environmental Toxicology and Chemistry, v. 26, no. 7, p. 1433-1440, https://doi.org/10.1897/06-451R1.1.","productDescription":"8 p.","startPage":"1433","endPage":"1440","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":238693,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":211409,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1897/06-451R1.1"}],"volume":"26","issue":"7","noUsgsAuthors":false,"publicationDate":"2007-07-01","publicationStatus":"PW","scienceBaseUri":"5059ed16e4b0c8380cd49606","contributors":{"authors":[{"text":"Lerner, Darrren T.","contributorId":51175,"corporation":false,"usgs":true,"family":"Lerner","given":"Darrren","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":428558,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bjornsson, Bjorn Thrandur","contributorId":28928,"corporation":false,"usgs":true,"family":"Bjornsson","given":"Bjorn","email":"","middleInitial":"Thrandur","affiliations":[],"preferred":false,"id":428560,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"McCormick, Stephen D. 0000-0003-0621-6200 smccormick@usgs.gov","orcid":"https://orcid.org/0000-0003-0621-6200","contributorId":2197,"corporation":false,"usgs":true,"family":"McCormick","given":"Stephen D.","email":"smccormick@usgs.gov","affiliations":[{"id":365,"text":"Leetown Science Center","active":true,"usgs":true}],"preferred":false,"id":428559,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030762,"text":"70030762 - 2007 - Atmospheric bromine flux from the coastal Abu Dhabi sabkhat: A ground-water mass-balance investigation","interactions":[],"lastModifiedDate":"2012-03-12T17:21:19","indexId":"70030762","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1807,"text":"Geophysical Research Letters","active":true,"publicationSubtype":{"id":10}},"title":"Atmospheric bromine flux from the coastal Abu Dhabi sabkhat: A ground-water mass-balance investigation","docAbstract":"A solute mass-balance study of ground water of the 3000 km2 coastal sabkhat (salt flats) of the Emirate of Abu Dhabi, United Arab Emirates, documents an annual bromide loss of approximately 255 metric tons (0.0032 Gmoles), or 85 kg/km2. This value is an order of magnitude greater than previously published direct measurements from the atmosphere over an evaporative environment of a salar in Bolivia. Laboratory evidence, consistent with published reports, suggests that this loss is by vapor transport to the atmosphere. If this bromine flux to the atmosphere is representative of the total earth area of active salt flats then it is a significant, and generally under recognized, input to the global atmospheric bromide flux.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geophysical Research Letters","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1029/2007GL029922","issn":"00948276","usgsCitation":"Wood, W., and Sanford, W., 2007, Atmospheric bromine flux from the coastal Abu Dhabi sabkhat: A ground-water mass-balance investigation: Geophysical Research Letters, v. 34, no. 14, https://doi.org/10.1029/2007GL029922.","costCenters":[],"links":[{"id":476991,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2007gl029922","text":"Publisher Index Page"},{"id":211381,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1029/2007GL029922"},{"id":238661,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"34","issue":"14","noUsgsAuthors":false,"publicationDate":"2007-07-31","publicationStatus":"PW","scienceBaseUri":"5059eebee4b0c8380cd49f01","contributors":{"authors":[{"text":"Wood, W.W.","contributorId":21974,"corporation":false,"usgs":true,"family":"Wood","given":"W.W.","email":"","affiliations":[],"preferred":false,"id":428553,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sanford, W. E. 0000-0002-6624-0280","orcid":"https://orcid.org/0000-0002-6624-0280","contributorId":102112,"corporation":false,"usgs":true,"family":"Sanford","given":"W. E.","affiliations":[],"preferred":false,"id":428554,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70030760,"text":"70030760 - 2007 - Spectral element modelling of fault-plane reflections arising from fluid pressure distributions","interactions":[],"lastModifiedDate":"2012-03-12T17:21:20","indexId":"70030760","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1803,"text":"Geophysical Journal International","active":true,"publicationSubtype":{"id":10}},"title":"Spectral element modelling of fault-plane reflections arising from fluid pressure distributions","docAbstract":"The presence of fault-plane reflections in seismic images, besides indicating the locations of faults, offers a possible source of information on the properties of these poorly understood zones. To better understand the physical mechanism giving rise to fault-plane reflections in compacting sedimentary basins, we numerically model the full elastic wavefield via the spectral element method (SEM) for several different fault models. Using well log data from the South Eugene Island field, offshore Louisiana, we derive empirical relationships between the elastic parameters (e.g. P-wave velocity and density) and the effective-stress along both normal compaction and unloading paths. These empirical relationships guide the numerical modelling and allow the investigation of how differences in fluid pressure modify the elastic wavefield. We choose to simulate the elastic wave equation via SEM since irregular model geometries can be accommodated and slip boundary conditions at an interface, such as a fault or fracture, are implemented naturally. The method we employ for including a slip interface retains the desirable qualities of SEM in that it is explicit in time and, therefore, does not require the inversion of a large matrix. We performa complete numerical study by forward modelling seismic shot gathers over a faulted earth model using SEM followed by seismic processing of the simulated data. With this procedure, we construct post-stack time-migrated images of the kind that are routinely interpreted in the seismic exploration industry. We dip filter the seismic images to highlight the fault-plane reflections prior to making amplitude maps along the fault plane. With these amplitude maps, we compare the reflectivity from the different fault models to diagnose which physical mechanism contributes most to observed fault reflectivity. To lend physical meaning to the properties of a locally weak fault zone characterized as a slip interface, we propose an equivalent-layer model under the assumption of weak scattering. This allows us to use the empirical relationships between density, velocity and effective stress from the South Eugene Island field to relate a slip interface to an amount of excess pore-pressure in a fault zone. ?? 2007 The Authors Journal compilation ?? 2007 RAS.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geophysical Journal International","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1111/j.1365-246X.2007.03437.x","issn":"0956540X","usgsCitation":"Haney, M., Snieder, R., Ampuero, J., and Hofmann, R., 2007, Spectral element modelling of fault-plane reflections arising from fluid pressure distributions: Geophysical Journal International, v. 170, no. 2, p. 933-951, https://doi.org/10.1111/j.1365-246X.2007.03437.x.","startPage":"933","endPage":"951","numberOfPages":"19","costCenters":[],"links":[{"id":476998,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1111/j.1365-246x.2007.03437.x","text":"Publisher Index Page"},{"id":211352,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1365-246X.2007.03437.x"},{"id":238628,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"170","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b953ce4b08c986b31ae07","contributors":{"authors":[{"text":"Haney, M.","contributorId":38264,"corporation":false,"usgs":true,"family":"Haney","given":"M.","email":"","affiliations":[],"preferred":false,"id":428548,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Snieder, R.","contributorId":63924,"corporation":false,"usgs":true,"family":"Snieder","given":"R.","email":"","affiliations":[],"preferred":false,"id":428549,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ampuero, J.-P.","contributorId":28801,"corporation":false,"usgs":true,"family":"Ampuero","given":"J.-P.","affiliations":[],"preferred":false,"id":428547,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hofmann, R.","contributorId":79699,"corporation":false,"usgs":true,"family":"Hofmann","given":"R.","email":"","affiliations":[],"preferred":false,"id":428550,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70030759,"text":"70030759 - 2007 - Paleoearthquakes on the southern San Andreas Fault, Wrightwood, California, 3000 to 1500 B.C.: A new method for evaluating paleoseismic evidence and earthquake horizons","interactions":[],"lastModifiedDate":"2023-07-31T12:11:21.803291","indexId":"70030759","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1135,"text":"Bulletin of the Seismological Society of America","onlineIssn":"1943-3573","printIssn":"0037-1106","active":true,"publicationSubtype":{"id":10}},"title":"Paleoearthquakes on the southern San Andreas Fault, Wrightwood, California, 3000 to 1500 B.C.: A new method for evaluating paleoseismic evidence and earthquake horizons","docAbstract":"We present evidence of 11–14 earthquakes that occurred between 3000 and 1500 b.c. on the San Andreas fault at the Wrightwood paleoseismic site. Earthquake evidence is presented in a novel form in which we rank (high, moderate, poor, or low) the quality of all evidence of ground deformation, which are called “event indicators.” Event indicator quality reflects our confidence that the morphologic and sedimentologic evidence can be attributable to a ground-deforming earthquake and that the earthquake horizon is accurately identified by the morphology of the feature. In four vertical meters of section exposed in ten trenches, we document 316 event indicators attributable to 32 separate stratigraphic horizons. Each stratigraphic horizon is evaluated based on the sum of rank (Rs), maximum rank (Rm), average rank (Ra), number of observations (Obs), and sum of higher-quality event indicators (Rs>1). Of the 32 stratigraphic horizons, 14 contain 83% of the event indicators and are qualified based on the number and quality of event indicators; the remaining 18 do not have satisfactory evidence for further consideration. Eleven of the 14 stratigraphic horizons have sufficient number and quality of event indicators to be qualified as “probable” to “very likely” earthquakes; the remaining three stratigraphic horizons are associated with somewhat ambiguous features and are qualified as “possible” earthquakes. Although no single measurement defines an obvious threshold for designation as an earthquake horizon, Rs, Rm, and Rs>1 correlate best with the interpreted earthquake quality. Earthquake age distributions are determined from radiocarbon ages of peat samples using a Bayesian approach to layer dating. The average recurrence interval for the 10 consecutive and highest-quality earthquakes is 111 (93–131) years and individual intervals are ±50% of the average. With comparison with the previously published 14–15 earthquake record between a.d. 500 and present, we find no evidence to suggest significant variations in the average recurrence rate at Wrightwood during the past 5000 years.
Available information on the distribution of breeding shorebirds across the Arctic Coastal Plain of Alaska is dated, fragmented, and limited in scope. Herein, we describe the distribution of 19 shorebird species from data gathered at 407 study plots between 1998 and 2004. This information was collected using a single-visit rapid area search technique during territory establishment and early incubation periods, a time when social displays and vocalizations make the birds highly detectable. We describe the presence or absence of each species, as well as overall numbers of species, providing a regional perspective on shorebird distribution. We compare and contrast our shorebird distribution maps to those of prior studies and describe prominent patterns of shorebird distribution. Our examination of how shorebird distribution and numbers of species varied both latitudinally and longitudinally across the Arctic Coastal Plain of Alaska indicated that most shorebird species occur more frequently in the Beaufort Coastal Plain ecoregion (i.e., closer to the coast) than in the Brooks Foothills ecoregion (i.e., farther inland). Furthermore, the occurrence of several species indicated substantial longitudinal directionality. Species richness at surveyed sites was highest in the western portion of the Beaufort Coastal Plain ecoregion. The broad-scale distribution information we present here is valuable for evaluating potential effects of human development and climate change on Arctic-breeding shorebird populations.
","language":"English","publisher":"Arctic Institute of North America","doi":"10.14430/arctic220","usgsCitation":"Johnson, J., Lanctot, R., Andres, B.A., Bart, J., Brown, S.C., Kendall, S.J., and Payer, D.C., 2007, Distribution of breeding shorebirds on the Arctic Coastal Plain of Alaska: Arctic, v. 60, no. 3, p. 277-293, https://doi.org/10.14430/arctic220.","productDescription":"17 p.","startPage":"277","endPage":"293","numberOfPages":"17","costCenters":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true}],"links":[{"id":477179,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.14430/arctic220","text":"Publisher Index Page"},{"id":238555,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Alaska","otherGeospatial":"Arctic Coastal Plain","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -160.76545815893368,\n 71.73753208468906\n ],\n [\n -162.3930009704475,\n 68.96864566870872\n ],\n [\n -142.67714191186246,\n 68.44977011466841\n ],\n [\n -142.2944316878697,\n 71.12036514995935\n ],\n [\n -160.76545815893368,\n 71.73753208468906\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"60","issue":"3","noUsgsAuthors":false,"publicationDate":"2009-12-10","publicationStatus":"PW","scienceBaseUri":"505a02c2e4b0c8380cd501bf","contributors":{"authors":[{"text":"Johnson, James A.","contributorId":84649,"corporation":false,"usgs":true,"family":"Johnson","given":"James A.","affiliations":[],"preferred":false,"id":428534,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lanctot, Richard B.","contributorId":77879,"corporation":false,"usgs":false,"family":"Lanctot","given":"Richard B.","affiliations":[{"id":6987,"text":"U.S. Fish and Wildlife Sevice","active":true,"usgs":false}],"preferred":false,"id":428533,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Andres, Brad A.","contributorId":317983,"corporation":false,"usgs":false,"family":"Andres","given":"Brad","email":"","middleInitial":"A.","affiliations":[{"id":12428,"text":"U. S. Fish and Wildlife Service","active":true,"usgs":false}],"preferred":false,"id":428536,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Bart, Jonathan jon_bart@usgs.gov","contributorId":57025,"corporation":false,"usgs":true,"family":"Bart","given":"Jonathan","email":"jon_bart@usgs.gov","affiliations":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true}],"preferred":false,"id":428535,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Brown, Stephen C.","contributorId":38457,"corporation":false,"usgs":false,"family":"Brown","given":"Stephen","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":428532,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Kendall, Steven J.","contributorId":30911,"corporation":false,"usgs":false,"family":"Kendall","given":"Steven","email":"","middleInitial":"J.","affiliations":[{"id":6987,"text":"U.S. Fish and Wildlife Sevice","active":true,"usgs":false}],"preferred":false,"id":428537,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Payer, David C.","contributorId":7495,"corporation":false,"usgs":false,"family":"Payer","given":"David","email":"","middleInitial":"C.","affiliations":[{"id":6987,"text":"U.S. Fish and Wildlife Sevice","active":true,"usgs":false}],"preferred":false,"id":428531,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70030750,"text":"70030750 - 2007 - Distinctiveness, use, and value of midwestern oak savannas and woodlands as avian habitats","interactions":[],"lastModifiedDate":"2017-05-08T07:51:12","indexId":"70030750","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3544,"text":"The Auk","onlineIssn":"1938-4254","printIssn":"0004-8038","active":true,"publicationSubtype":{"id":10}},"title":"Distinctiveness, use, and value of midwestern oak savannas and woodlands as avian habitats","docAbstract":"Oak savannas and woodlands historically covered millions of hectares in the midwestern United States but are rare today. We evaluated the ecological distinctiveness and conservation value of savannas and woodlands by examining bird distributions across a fire-maintained woody-vegetation gradient in northwest Indiana encompassing five habitats—open habitats with low canopy cover, savannas, woodlands, scrublands, and forests—during migration, breeding, and overwintering. Savannas and woodlands were significantly different in overall bird species composition from open and forest habitats but were often intermediate between open and forest in guild densities. Few bird species were consistently and highly concentrated in savannas or woodlands, and the Red-headed Woodpecker (Melanerpes erythrocephalus) was the only species significantly more abundant in savannas and woodlands than in open, scrub, and forest habitats. Fire frequency over a 15-year interval was a significant predictor of bird community composition and was positively related to species diversity, spring transient migrant density, and density of the most threatened species. Each habitat type had characteristics potentially important for avian conservation. Scrub had the highest density of transient migrants, which suggests it plays an important role as migration stopover habitat. More species were significantly concentrated in open or forest habitats than in the other habitats. Lack of species concentration and intermediate community composition suggested that birds experienced savannas and woodlands more as ecotones than as habitats distinct from forests or grasslands. However, this intermediate character can benefit conservation, as evidenced by savannas and woodlands having the highest density of the most threatened species along this woody-vegetation gradient.
","language":"English","publisher":"American Ornithological Society","doi":"10.1642/0004-8038(2007)124[969:DUAVOM]2.0.CO;2","issn":"00048038","usgsCitation":"Grundel, R., and Pavlovic, N., 2007, Distinctiveness, use, and value of midwestern oak savannas and woodlands as avian habitats: The Auk, v. 124, no. 3, p. 969-985, https://doi.org/10.1642/0004-8038(2007)124[969:DUAVOM]2.0.CO;2.","productDescription":"17 p.","startPage":"969","endPage":"985","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":238954,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"124","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a024de4b0c8380cd4ffb8","contributors":{"authors":[{"text":"Grundel, R.","contributorId":37110,"corporation":false,"usgs":true,"family":"Grundel","given":"R.","affiliations":[],"preferred":false,"id":428516,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Pavlovic, N.B.","contributorId":105076,"corporation":false,"usgs":true,"family":"Pavlovic","given":"N.B.","email":"","affiliations":[],"preferred":false,"id":428517,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70030748,"text":"70030748 - 2007 - The instantaneous rate dependence in low temperature laboratory rock friction and rock deformation experiments","interactions":[],"lastModifiedDate":"2023-08-01T12:11:33.968611","indexId":"70030748","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"The instantaneous rate dependence in low temperature laboratory rock friction and rock deformation experiments","docAbstract":"[1] Earthquake occurrence probabilities that account for stress transfer and time-dependent failure depend on the product of the effective normal stress and a lab-derived dimensionless coefficient a. This coefficient describes the instantaneous dependence of fault strength on deformation rate, and determines the duration of precursory slip. Although an instantaneous rate dependence is observed for fracture, friction, crack growth, and low temperature plasticity in laboratory experiments, the physical origin of this effect during earthquake faulting is obscure. We examine this rate dependence in laboratory experiments on different rock types using a normalization scheme modified from one proposed by Tullis and Weeks [1987]. We compare the instantaneous rate dependence in rock friction with rate dependence measurements from higher temperature dislocation glide experiments. The same normalization scheme is used to compare rate dependence in friction to rock fracture and to low-temperature crack growth tests. For particular weak phyllosilicate minerals, the instantaneous friction rate dependence is consistent with dislocation glide. In intact rock failure tests, for each rock type considered, the instantaneous rate dependence is the same size as for friction, suggesting a common physical origin. During subcritical crack growth in strong quartzofeldspathic and carbonate rock where glide is not possible, the instantaneous rate dependence measured during failure or creep tests at high stress has long been thought to be due to crack growth; however, direct comparison between crack growth and friction tests shows poor agreement. The crack growth rate dependence appears to be higher than the rate dependence of friction and fracture by a factor of two to three for all rock types considered.
As populations grow in arid climates and desert bedrock aquifers are increasingly targeted for future development, understanding and quantifying the spatial variability of net infiltration becomes critically important for accurately inventorying water resources and mapping contamination vulnerability. This paper presents a conceptual model of net infiltration to desert sandstone and then develops an empirical equation for its spatial quantification at the watershed scale using linear least squares inversion methods for evaluating controlling parameters (independent variables) based on estimated net infiltration rates (dependent variables). Net infiltration rates used for this regression analysis were calculated from environmental tracers in boreholes and more than 3000 linear meters of vadose zone excavations in an upland basin in southwestern Utah underlain by Navajo sandstone. Soil coarseness, distance to upgradient outcrop, and topographic slope were shown to be the primary physical parameters controlling the spatial variability of net infiltration. Although the method should be transferable to other desert sandstone settings for determining the relative spatial distribution of net infiltration, further study is needed to evaluate the effects of other potential parameters such as slope aspect, outcrop parameters, and climate on absolute net infiltration rates.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2006WR005113","usgsCitation":"Heilweil, V.M., McKinney, T., Zhdanov, M.S., and Watt, D.E., 2007, Controls on the variability of net infiltration to desert sandstone: Water Resources Research, v. 43, no. 7, Article W07431; 15 p., https://doi.org/10.1029/2006WR005113.","productDescription":"Article W07431; 15 p.","costCenters":[],"links":[{"id":477213,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2006wr005113","text":"Publisher Index Page"},{"id":239221,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"43","issue":"7","noUsgsAuthors":false,"publicationDate":"2007-07-18","publicationStatus":"PW","scienceBaseUri":"5059fbd5e4b0c8380cd4dfc5","contributors":{"authors":[{"text":"Heilweil, Victor M. heilweil@usgs.gov","contributorId":837,"corporation":false,"usgs":true,"family":"Heilweil","given":"Victor","email":"heilweil@usgs.gov","middleInitial":"M.","affiliations":[{"id":610,"text":"Utah Water Science Center","active":true,"usgs":true}],"preferred":true,"id":428443,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McKinney, Tim S.","contributorId":66792,"corporation":false,"usgs":true,"family":"McKinney","given":"Tim S.","affiliations":[],"preferred":false,"id":428445,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Zhdanov, Michael S.","contributorId":37955,"corporation":false,"usgs":false,"family":"Zhdanov","given":"Michael","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":428444,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Watt, Dennis E.","contributorId":55286,"corporation":false,"usgs":true,"family":"Watt","given":"Dennis","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":428442,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70030730,"text":"70030730 - 2007 - Population estimates of Hyla cinerea (Schneider) (Green Tree frog) in an urban environment","interactions":[],"lastModifiedDate":"2012-03-12T17:21:01","indexId":"70030730","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3444,"text":"Southeastern Naturalist","active":true,"publicationSubtype":{"id":10}},"title":"Population estimates of Hyla cinerea (Schneider) (Green Tree frog) in an urban environment","docAbstract":"Hyla cinerea (Green Treefrog) is a common wetlands species in the southeastern US. To better understand its population dynamics, we followed a relatively isolated population of Green Treefrogs from June 2004 through October 2004 at a federal office complex in Lafayette, LA. Weekly, Green Treefrogs were caught, measured, marked with VIE tags, and released. The data were used to estimate population size. The time frame was split into two periods: before and after August 17, 2004. Before August 17, 2004, the average estimated population size was 143, and after August 24, 2005, this value jumped to 446, an increase possibly due to tadpoles metamorphosing into adults.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Southeastern Naturalist","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1656/1528-7092(2007)6[203:PEOHCS]2.0.CO;2","issn":"15287092","usgsCitation":"Pham, L., Boudreaux, S., Karhbet, S., Price, B., Ackleh, A., Carter, J., and Pal, N., 2007, Population estimates of Hyla cinerea (Schneider) (Green Tree frog) in an urban environment: Southeastern Naturalist, v. 6, no. 2, p. 203-216, https://doi.org/10.1656/1528-7092(2007)6[203:PEOHCS]2.0.CO;2.","startPage":"203","endPage":"216","numberOfPages":"14","costCenters":[],"links":[{"id":239186,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":211821,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1656/1528-7092(2007)6[203:PEOHCS]2.0.CO;2"}],"volume":"6","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7d6de4b0c8380cd79f37","contributors":{"authors":[{"text":"Pham, L.","contributorId":104283,"corporation":false,"usgs":true,"family":"Pham","given":"L.","email":"","affiliations":[],"preferred":false,"id":428426,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Boudreaux, S.","contributorId":68106,"corporation":false,"usgs":true,"family":"Boudreaux","given":"S.","email":"","affiliations":[],"preferred":false,"id":428422,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Karhbet, S.","contributorId":76941,"corporation":false,"usgs":true,"family":"Karhbet","given":"S.","email":"","affiliations":[],"preferred":false,"id":428423,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Price, B.","contributorId":15406,"corporation":false,"usgs":true,"family":"Price","given":"B.","email":"","affiliations":[],"preferred":false,"id":428421,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Ackleh, A. S.","contributorId":14787,"corporation":false,"usgs":false,"family":"Ackleh","given":"A. S.","affiliations":[],"preferred":false,"id":428420,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Carter, J. 0000-0003-0110-0284 carterj@usgs.gov","orcid":"https://orcid.org/0000-0003-0110-0284","contributorId":81839,"corporation":false,"usgs":true,"family":"Carter","given":"J.","email":"carterj@usgs.gov","affiliations":[{"id":455,"text":"National Wetlands Research Center","active":true,"usgs":true}],"preferred":true,"id":428425,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Pal, N.","contributorId":79702,"corporation":false,"usgs":true,"family":"Pal","given":"N.","email":"","affiliations":[],"preferred":false,"id":428424,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70030727,"text":"70030727 - 2007 - GIS methodology for quantifying channel change in Las Vegas, Nevada","interactions":[],"lastModifiedDate":"2012-03-12T17:21:01","indexId":"70030727","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2529,"text":"Journal of the American Water Resources Association","active":true,"publicationSubtype":{"id":10}},"title":"GIS methodology for quantifying channel change in Las Vegas, Nevada","docAbstract":"This study applies spatial analyses to examine the consequences of accelerated urban expansion on a hydrologic system over a period of 24 years. Three sets of historical aerial photos are used in a GIS analysis to document the geomorphic history of Las Vegas Wash, which drains the rapidly growing Las Vegas urban area in southern Nevada. New spatial techniques are introduced to make quantitative measurements of the erosion at three specific time intervals in the hydrologic evolution of the channel and floodplain. Unlike other erosion studies that use two different elevation surfaces to assess erosion, this study used a single elevation surface to remove systematic and nonsystemic elevation errors. The spatial analysis quantifies channel changes for discrete time periods, calculates erosion volumes, and provides a foundation to examine how the specific mechanisms related to urban expansion have affected Las Vegas Wash. The erosion calculated over 24 years is the largest documented sediment loss attributed to the effect of rapid urban growth. ?? 2007 American Water Resources Association.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of the American Water Resources Association","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1111/j.1752-1688.2007.00073.x","issn":"1093474X","usgsCitation":"Buckingham, S., and Whitney, J., 2007, GIS methodology for quantifying channel change in Las Vegas, Nevada: Journal of the American Water Resources Association, v. 43, no. 4, p. 888-898, https://doi.org/10.1111/j.1752-1688.2007.00073.x.","startPage":"888","endPage":"898","numberOfPages":"11","costCenters":[],"links":[{"id":211767,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1752-1688.2007.00073.x"},{"id":239119,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"43","issue":"4","noUsgsAuthors":false,"publicationDate":"2007-06-28","publicationStatus":"PW","scienceBaseUri":"505a146ae4b0c8380cd54a15","contributors":{"authors":[{"text":"Buckingham, S.E.","contributorId":9454,"corporation":false,"usgs":true,"family":"Buckingham","given":"S.E.","email":"","affiliations":[],"preferred":false,"id":428408,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Whitney, J.W.","contributorId":27437,"corporation":false,"usgs":true,"family":"Whitney","given":"J.W.","email":"","affiliations":[],"preferred":false,"id":428409,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70030725,"text":"70030725 - 2007 - Temporal trends in concentrations of DBCP and nitrate in groundwater in the eastern San Joaquin Valley, California, USA","interactions":[],"lastModifiedDate":"2018-09-13T14:28:19","indexId":"70030725","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1923,"text":"Hydrogeology Journal","active":true,"publicationSubtype":{"id":10}},"title":"Temporal trends in concentrations of DBCP and nitrate in groundwater in the eastern San Joaquin Valley, California, USA","docAbstract":"Temporal monitoring of the pesticide 1,2-dibromo-3-chloropropane (DBCP) and nitrate and indicators of mean groundwater age were used to evaluate the transport and fate of agricultural chemicals in groundwater and to predict the long-term effects in the regional aquifer system in the eastern San Joaquin Valley, California. Twenty monitoring wells were installed on a transect along an approximate groundwater flow path. Concentrations of DBCP and nitrate in the wells were compared to concentrations in regional areal monitoring networks. DBCP persists at concentrations above the US Environmental Protection Agency's maximum contaminant level (MCL) at depths of nearly 40 m below the water table, more than 25 years after it was banned. Nitrate concentrations above the MCL reached depths of more than 20 m below the water table. Because of the intensive pumping and irrigation recharge, vertical flow paths are dominant. High concentrations (above MCLs) in the shallow part of the regional aquifer system will likely move deeper in the system, affecting both domestic and public-supply wells. The large fraction of old water (unaffected by agricultural chemicals) in deep monitoring wells suggests that it could take decades for concentrations to reach MCLs in deep, long-screened public-supply wells, however. ?? Springer-Verlag 2007.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrogeology Journal","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s10040-006-0148-7","issn":"14312174","usgsCitation":"Burow, K., Dubrovsky, N., and Shelton, J.L., 2007, Temporal trends in concentrations of DBCP and nitrate in groundwater in the eastern San Joaquin Valley, California, USA: Hydrogeology Journal, v. 15, no. 5, p. 991-1007, https://doi.org/10.1007/s10040-006-0148-7.","startPage":"991","endPage":"1007","numberOfPages":"17","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":239117,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":211765,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10040-006-0148-7"}],"volume":"15","issue":"5","noUsgsAuthors":false,"publicationDate":"2007-01-16","publicationStatus":"PW","scienceBaseUri":"505ba51ce4b08c986b320800","contributors":{"authors":[{"text":"Burow, K.R. 0000-0001-6006-6667","orcid":"https://orcid.org/0000-0001-6006-6667","contributorId":48283,"corporation":false,"usgs":true,"family":"Burow","given":"K.R.","affiliations":[],"preferred":false,"id":428403,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dubrovsky, N. M.","contributorId":48199,"corporation":false,"usgs":true,"family":"Dubrovsky","given":"N. M.","affiliations":[],"preferred":false,"id":428402,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Shelton, James L.","contributorId":85319,"corporation":false,"usgs":false,"family":"Shelton","given":"James","email":"","middleInitial":"L.","affiliations":[{"id":13267,"text":"Warnell School of Forestry and Natural Resources, University of Georgia","active":true,"usgs":false}],"preferred":false,"id":428404,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030720,"text":"70030720 - 2007 - Minimizing noise in fiberglass aquaculture tanks: Noise reduction potential of various retrofits","interactions":[],"lastModifiedDate":"2012-03-12T17:21:14","indexId":"70030720","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":852,"text":"Aquacultural Engineering","active":true,"publicationSubtype":{"id":10}},"title":"Minimizing noise in fiberglass aquaculture tanks: Noise reduction potential of various retrofits","docAbstract":"Equipment used in intensive aquaculture systems, such as pumps and blowers can produce underwater sound levels and frequencies within the range of fish hearing. The impacts of underwater noise on fish are not well known, but limited research suggests that subjecting fish to noise could result in impairment of the auditory system, reduced growth rates, and increased stress. Consequently, reducing sound in fish tanks could result in advantages for cultured species and increased productivity for the aquaculture industry. The objective of this study was to evaluate the noise reduction potential of various retrofits to fiberglass fish culture tanks. The following structural changes were applied to tanks to reduce underwater noise: (1) inlet piping was suspended to avoid contact with the tank, (2) effluent piping was disconnected from a common drain line, (3) effluent piping was insulated beneath tanks, and (4) tanks were elevated on cement blocks and seated on insulated padding. Four combinations of the aforementioned structural changes were evaluated in duplicate and two tanks were left unchanged as controls. Control tanks had sound levels of 120.6 dB re 1 ??Pa. Each retrofit contributed to a reduction of underwater sound. As structural changes were combined, a cumulative reduction in sound level was observed. Tanks designed with a combination of retrofits had sound levels of 108.6 dB re 1 ??Pa, a four-fold reduction in sound pressure level. Sound frequency spectra indicated that the greatest sound reductions occurred between 2 and 100 Hz and demonstrated that nearby pumps and blowers created tonal frequencies that were transmitted into the tanks. The tank modifications used during this study were simple and inexpensive and could be applied to existing systems or considered when designing aquaculture facilities. ?? 2007 Elsevier B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Aquacultural Engineering","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.aquaeng.2007.03.003","issn":"01448609","usgsCitation":"Davidson, J., Frankel, A., Ellison, W., Summerfelt, S., Popper, A., Mazik, P., and Bebak, J., 2007, Minimizing noise in fiberglass aquaculture tanks: Noise reduction potential of various retrofits: Aquacultural Engineering, v. 37, no. 2, p. 125-131, https://doi.org/10.1016/j.aquaeng.2007.03.003.","startPage":"125","endPage":"131","numberOfPages":"7","costCenters":[],"links":[{"id":476994,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1016/j.aquaeng.2007.03.003","text":"Publisher Index Page"},{"id":239607,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":212164,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.aquaeng.2007.03.003"}],"volume":"37","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5afee4b0c8380cd6f265","contributors":{"authors":[{"text":"Davidson, J.","contributorId":107100,"corporation":false,"usgs":true,"family":"Davidson","given":"J.","affiliations":[],"preferred":false,"id":428385,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Frankel, A.S.","contributorId":30821,"corporation":false,"usgs":true,"family":"Frankel","given":"A.S.","email":"","affiliations":[],"preferred":false,"id":428381,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ellison, W.T.","contributorId":31203,"corporation":false,"usgs":true,"family":"Ellison","given":"W.T.","email":"","affiliations":[],"preferred":false,"id":428382,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Summerfelt, S.","contributorId":46051,"corporation":false,"usgs":true,"family":"Summerfelt","given":"S.","email":"","affiliations":[],"preferred":false,"id":428384,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Popper, A.N.","contributorId":15010,"corporation":false,"usgs":true,"family":"Popper","given":"A.N.","email":"","affiliations":[],"preferred":false,"id":428379,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Mazik, P.","contributorId":22145,"corporation":false,"usgs":true,"family":"Mazik","given":"P.","affiliations":[],"preferred":false,"id":428380,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Bebak, J.","contributorId":31704,"corporation":false,"usgs":true,"family":"Bebak","given":"J.","affiliations":[],"preferred":false,"id":428383,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70030719,"text":"70030719 - 2007 - Passive aerobic treatment of net-alkaline, iron-laden drainage from a flooded underground anthracite mine, Pennsylvania, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:21:10","indexId":"70030719","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2745,"text":"Mine Water and the Environment","active":true,"publicationSubtype":{"id":10}},"title":"Passive aerobic treatment of net-alkaline, iron-laden drainage from a flooded underground anthracite mine, Pennsylvania, USA","docAbstract":"This report evaluates the results of a continuous 4.5-day laboratory aeration experiment and the first year of passive, aerobic treatment of abandoned mine drainage (AMD) from a typical flooded underground anthracite mine in eastern Pennsylvania, USA. During 1991-2006, the AMD source, locally known as the Otto Discharge, had flows from 20 to 270 L/s (median 92 L/s) and water quality that was consistently suboxic (median 0.9 mg/L O2) and circumneutral (pH ??? 6.0; net alkalinity >10) with moderate concentrations of dissolved iron and manganese and low concentrations of dissolved aluminum (medians of 11, 2.2, and <0.2 mg/L, respectively). In 2001, the laboratory aeration experiment demonstrated rapid oxidation of ferrous iron (Fe 2+) without supplemental alkalinity; the initial Fe2+ concentration of 16.4 mg/L decreased to less than 0.5 mg/L within 24 h; pH values increased rapidly from 5.8 to 7.2, ultimately attaining a steady-state value of 7.5. The increased pH coincided with a rapid decrease in the partial pressure of carbon dioxide (PCO2) from an initial value of 10 -1.1atm to a steady-state value of 10-3.1atm. From these results, a staged aerobic treatment system was conceptualized consisting of a 2 m deep pond with innovative aeration and recirculation to promote rapid oxidation of Fe2+, two 0.3 m deep wetlands to facilitate iron solids removal, and a supplemental oxic limestone drain for dissolved manganese and trace-metal removal. The system was constructed, but without the aeration mechanism, and began operation in June 2005. During the first 12 months of operation, estimated detention times in the treatment system ranged from 9 to 38 h. However, in contrast with 80-100% removal of Fe2+ over similar elapsed times during the laboratory aeration experiment, the treatment system typically removed less than 35% of the influent Fe2+. Although concentrations of dissolved CO2 decreased progressively within the treatment system, the PCO2 values for treated effluent remained elevated (10-2.4 to 10-1.7atm). The elevated PCO 2 maintained the pH within the system at values less than 7 and hence slowed the rate of Fe2+ oxidation compared to the aeration experiment. Kinetic models of Fe2+ oxidation that consider effects of pH and dissolved O2 were incorporated in the geochemical computer program PHREEQC to evaluate the effects of detention time, pH, and other variables on Fe2+ oxidation and removal rates. These models and the laboratory aeration experiment indicate that performance of this and other aerobic wetlands for treatment of net-alkaline AMD could be improved by aggressive, continuous aeration in the initial stage to decrease PCO 2, increase pH, and accelerate Fe2+ oxidation. ?? 2007 Springer-Verlag.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Mine Water and the Environment","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s10230-007-0002-8","issn":"10259112","usgsCitation":"Cravotta, C., 2007, Passive aerobic treatment of net-alkaline, iron-laden drainage from a flooded underground anthracite mine, Pennsylvania, USA: Mine Water and the Environment, v. 26, no. 3, p. 128-149, https://doi.org/10.1007/s10230-007-0002-8.","startPage":"128","endPage":"149","numberOfPages":"22","costCenters":[],"links":[{"id":212138,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10230-007-0002-8"},{"id":239574,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"26","issue":"3","noUsgsAuthors":false,"publicationDate":"2007-08-18","publicationStatus":"PW","scienceBaseUri":"505a7576e4b0c8380cd77b70","contributors":{"authors":[{"text":"Cravotta, C.A. III","contributorId":18405,"corporation":false,"usgs":true,"family":"Cravotta","given":"C.A.","suffix":"III","email":"","affiliations":[],"preferred":false,"id":428378,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70030579,"text":"70030579 - 2007 - Simulation of submarine groundwater discharge salinity and temperature variations: Implications for remote detection","interactions":[],"lastModifiedDate":"2012-03-12T17:21:14","indexId":"70030579","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Simulation of submarine groundwater discharge salinity and temperature variations: Implications for remote detection","docAbstract":"A hydrological analysis using a numerical simulation was done to identify the transient response of the salinity and temperature of submarine groundwater discharge (SGD) and utilize the results to guide data collection. Results indicate that the amount of SGD fluctuates depending on the ocean stage and geology, with the greatest amount of SGD delivered at low tide when the aquifer is in direct hydraulic contact with the ocean. The salinity of SGD remains lower than the ocean throughout the year; however, the salinity difference between the aquifer and ocean is inversely proportional to the ocean stage. The temperature difference between the ocean and SGD fluctuates seasonally, with the greatest temperature differences occurring in summer and winter. The outcome of this research reveals that numerical modelling could potentially be used to guide data collection including aerial surveys using electromagnetic (EM) resistivity and thermal imagery.","largerWorkTitle":"IAHS-AISH Publication","conferenceTitle":"International Symposium: A New Focus on Groundwater - Seawater Interactions - 24th General Assembly of the In","conferenceDate":"2 July 2007 through 13 July 2007","conferenceLocation":"Perugia","language":"English","issn":"01447","isbn":"9781901502046","usgsCitation":"Dausman, A., Langevin, C., and Sukop, M., 2007, Simulation of submarine groundwater discharge salinity and temperature variations: Implications for remote detection, in IAHS-AISH Publication, no. 312, Perugia, 2 July 2007 through 13 July 2007, p. 272-280.","startPage":"272","endPage":"280","numberOfPages":"9","costCenters":[],"links":[{"id":239564,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"issue":"312","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9098e4b08c986b3195c4","contributors":{"authors":[{"text":"Dausman, A.M.","contributorId":99373,"corporation":false,"usgs":true,"family":"Dausman","given":"A.M.","affiliations":[],"preferred":false,"id":427729,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Langevin, C.D.","contributorId":25976,"corporation":false,"usgs":true,"family":"Langevin","given":"C.D.","email":"","affiliations":[],"preferred":false,"id":427727,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Sukop, M.C.","contributorId":88468,"corporation":false,"usgs":true,"family":"Sukop","given":"M.C.","affiliations":[],"preferred":false,"id":427728,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030545,"text":"70030545 - 2007 - Glacier mass-balance fluctuations in the Pacific Northwest and Alaska, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:21:13","indexId":"70030545","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Glacier mass-balance fluctuations in the Pacific Northwest and Alaska, USA","docAbstract":"The more than 40 year record of net and seasonal mass-balance records from measurements made by the United States Geological Survey on South Cascade Glacier, Washington, and Wolverine and Gulkana Glaciers, Alaska, shows annual and interannual fluctuations that reflect changes in the controlling climatic conditions at regional and global scales. As the mass-balance record grows in length, it is revealing significant changes in previously described glacier mass-balance behavior, and both inter-glacier and glacier-climate relationships. South Cascade and Wolverine Glaciers are strongly affected by the warm and wet maritime climate of the northeast Pacific Ocean. Their net balances have generally been controlled by winter accumulation, with fluctuations that are strongly related to the Pacific Decadal Oscillation (PDO). Recently, warm dry summers have begun to dominate the net balance of the two maritime glaciers, with a weakening of the correlation between the winter balance fluctuations and the PDO. Non-synchronous periods of positive and negative net balance for each glacier prior to 1989 were followed by a 1989-2004 period of synchronous and almost exclusively negative net balances that averaged -0.8 m for the three glaciers.","largerWorkTitle":"Annals of Glaciology","language":"English","doi":"10.3189/172756407782871314","issn":"02603","usgsCitation":"Josberger, E., Bidlake, W.R., March, R., and Kennedy, B., 2007, Glacier mass-balance fluctuations in the Pacific Northwest and Alaska, USA, in Annals of Glaciology, v. 46, p. 291-296, https://doi.org/10.3189/172756407782871314.","startPage":"291","endPage":"296","numberOfPages":"6","costCenters":[],"links":[{"id":477159,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.3189/172756407782871314","text":"Publisher Index Page"},{"id":239594,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":212155,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.3189/172756407782871314"}],"volume":"46","noUsgsAuthors":false,"publicationDate":"2017-09-14","publicationStatus":"PW","scienceBaseUri":"505a2917e4b0c8380cd5a687","contributors":{"authors":[{"text":"Josberger, E.G.","contributorId":61161,"corporation":false,"usgs":true,"family":"Josberger","given":"E.G.","email":"","affiliations":[],"preferred":false,"id":427595,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bidlake, W. R.","contributorId":28953,"corporation":false,"usgs":true,"family":"Bidlake","given":"W.","middleInitial":"R.","affiliations":[],"preferred":false,"id":427594,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"March, R.S.","contributorId":16431,"corporation":false,"usgs":true,"family":"March","given":"R.S.","email":"","affiliations":[],"preferred":false,"id":427593,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Kennedy, B.W.","contributorId":78772,"corporation":false,"usgs":true,"family":"Kennedy","given":"B.W.","email":"","affiliations":[],"preferred":false,"id":427596,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70030544,"text":"70030544 - 2007 - Monitoring microearthquakes with the San Andreas fault observatory at depth","interactions":[],"lastModifiedDate":"2012-03-12T17:21:13","indexId":"70030544","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Monitoring microearthquakes with the San Andreas fault observatory at depth","docAbstract":"In 2005, the San Andreas Fault Observatory at Depth (SAFOD) was drilled through the San Andreas Fault zone at a depth of about 3.1 km. The borehole has subsequently been instrumented with high-frequency geophones in order to better constrain locations and source processes of nearby microearthquakes that will be targeted in the upcoming phase of SAFOD. The microseismic monitoring software MIMO, developed by NORSAR, has been installed at SAFOD to provide near-real time locations and magnitude estimates using the high sampling rate (4000 Hz) waveform data. To improve the detection and location accuracy, we incorporate data from the nearby, shallow borehole (???250 m) seismometers of the High Resolution Seismic Network (HRSN). The event association algorithm of the MIMO software incorporates HRSN detections provided by the USGS real time earthworm software. The concept of the new event association is based on the generalized beam forming, primarily used in array seismology. The method requires the pre-computation of theoretical travel times in a 3D grid of potential microearthquake locations to the seismometers of the current station network. By minimizing the differences between theoretical and observed detection times an event is associated and the location accuracy is significantly improved.","largerWorkTitle":"Society of Petroleum Engineers - 69th European Association of Geoscientists and Engineers Conference and Exhibition 2007 - \"Securing","conferenceTitle":"69th European Association of Geoscientists and Engineers Conference and Exhibition 2007 - ","conferenceDate":"11 June 2007 through 14 June 2007","conferenceLocation":"London","language":"English","isbn":"9781605601557","usgsCitation":"Oye, V., and Ellsworth, W., 2007, Monitoring microearthquakes with the San Andreas fault observatory at depth, in Society of Petroleum Engineers - 69th European Association of Geoscientists and Engineers Conference and Exhibition 2007 - \"Securing, v. 2, London, 11 June 2007 through 14 June 2007, p. 747-751.","startPage":"747","endPage":"751","numberOfPages":"5","costCenters":[],"links":[{"id":239560,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5dbfe4b0c8380cd70588","contributors":{"authors":[{"text":"Oye, V.","contributorId":90100,"corporation":false,"usgs":true,"family":"Oye","given":"V.","affiliations":[],"preferred":false,"id":427592,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ellsworth, W.L.","contributorId":48541,"corporation":false,"usgs":true,"family":"Ellsworth","given":"W.L.","email":"","affiliations":[],"preferred":false,"id":427591,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70030354,"text":"70030354 - 2007 - Red-shouldered hawk occupancy surveys in central Minnesota, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:21:03","indexId":"70030354","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2508,"text":"Journal of Wildlife Management","active":true,"publicationSubtype":{"id":10}},"title":"Red-shouldered hawk occupancy surveys in central Minnesota, USA","docAbstract":"Forest-dwelling raptors are often difficult to detect because many species occur at low density or are secretive. Broadcasting conspecific vocalizations can increase the probability of detecting forest-dwelling raptors and has been shown to be an effective method for locating raptors and assessing their relative abundance. Recent advances in statistical techniques based on presence-absence data use probabilistic arguments to derive probability of detection when it is <1 and to provide a model and likelihood-based method for estimating proportion of sites occupied. We used these maximum-likelihood models with data from red-shouldered hawk (Buteo lineatus) call-broadcast surveys conducted in central Minnesota, USA, in 1994-1995 and 2004-2005. Our objectives were to obtain estimates of occupancy and detection probability 1) over multiple sampling seasons (yr), 2) incorporating within-season time-specific detection probabilities, 3) with call type and breeding stage included as covariates in models of probability of detection, and 4) with different sampling strategies. We visited individual survey locations 2-9 times per year, and estimates of both probability of detection (range = 0.28-0.54) and site occupancy (range = 0.81-0.97) varied among years. Detection probability was affected by inclusion of a within-season time-specific covariate, call type, and breeding stage. In 2004 and 2005 we used survey results to assess the effect that number of sample locations, double sampling, and discontinued sampling had on parameter estimates. We found that estimates of probability of detection and proportion of sites occupied were similar across different sampling strategies, and we suggest ways to reduce sampling effort in a monitoring program.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Wildlife Management","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.2193/2006-013","issn":"00225","usgsCitation":"Henneman, C., McLeod, M., and Andersen, D., 2007, Red-shouldered hawk occupancy surveys in central Minnesota, USA: Journal of Wildlife Management, v. 71, no. 2, p. 526-533, https://doi.org/10.2193/2006-013.","startPage":"526","endPage":"533","numberOfPages":"8","costCenters":[],"links":[{"id":211950,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.2193/2006-013"},{"id":239338,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"71","issue":"2","noUsgsAuthors":false,"publicationDate":"2010-12-13","publicationStatus":"PW","scienceBaseUri":"50e4a3a0e4b0e8fec6cdb8de","contributors":{"authors":[{"text":"Henneman, C.","contributorId":64879,"corporation":false,"usgs":true,"family":"Henneman","given":"C.","affiliations":[],"preferred":false,"id":426816,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McLeod, M.A.","contributorId":66437,"corporation":false,"usgs":true,"family":"McLeod","given":"M.A.","email":"","affiliations":[],"preferred":false,"id":426817,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Andersen, D. E.","contributorId":27816,"corporation":false,"usgs":true,"family":"Andersen","given":"D. E.","affiliations":[],"preferred":false,"id":426815,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030211,"text":"70030211 - 2007 - A comparison of shoreline seines with fyke nets for sampling littoral fish communities in floodplain lakes","interactions":[],"lastModifiedDate":"2012-03-12T17:21:01","indexId":"70030211","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2886,"text":"North American Journal of Fisheries Management","active":true,"publicationSubtype":{"id":10}},"title":"A comparison of shoreline seines with fyke nets for sampling littoral fish communities in floodplain lakes","docAbstract":"We compared shoreline seines with fyke nets in terms of their ability to sample fish species in the littoral zone of 22 floodplain lakes of the White River, Arkansas. Lakes ranged in size from less than 0.5 to 51.0 ha. Most contained large amounts of coarse woody debris within the littoral zone, thus making seining in shallow areas difficult. We sampled large lakes (>2 ha) using three fyke nets; small lakes (<2 ha) were sampled using two fyke nets. Fyke nets were set for 24 h. Large lakes were sampled with an average of 11 seine hauls/ lake and small lakes were sampled with an average of 3 seine hauls/lake, but exact shoreline seining effort varied among lakes depending on the amount of open shoreline. Fyke nets collected more fish and produced greater species richness and diversity measures than did seining. Species evenness was similar for the two gear types. Two species were unique to seine samples, whereas 13 species and 3 families were unique to fyke-net samples. Although fyke nets collected more fish and more species than did shoreline seines, neither gear collected all the species present in the littoral zone of floodplain lakes. These results confirm the need for a multiple-gear approach to fully characterize the littoral fish assemblages in floodplain lakes. ?? Copyright by the American Fisheries Society 2007.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"North American Journal of Fisheries Management","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1577/M06-197.1","issn":"02755947","usgsCitation":"Clark, S., Jackson, J., and Lochmann, S., 2007, A comparison of shoreline seines with fyke nets for sampling littoral fish communities in floodplain lakes: North American Journal of Fisheries Management, v. 27, no. 2, p. 676-680, https://doi.org/10.1577/M06-197.1.","startPage":"676","endPage":"680","numberOfPages":"5","costCenters":[],"links":[{"id":239292,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":211913,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1577/M06-197.1"}],"volume":"27","issue":"2","noUsgsAuthors":false,"publicationDate":"2007-05-01","publicationStatus":"PW","scienceBaseUri":"5059e372e4b0c8380cd46024","contributors":{"authors":[{"text":"Clark, S.J.","contributorId":67724,"corporation":false,"usgs":true,"family":"Clark","given":"S.J.","email":"","affiliations":[],"preferred":false,"id":426140,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jackson, J.R.","contributorId":102273,"corporation":false,"usgs":true,"family":"Jackson","given":"J.R.","email":"","affiliations":[],"preferred":false,"id":426142,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lochmann, S.E.","contributorId":91692,"corporation":false,"usgs":true,"family":"Lochmann","given":"S.E.","affiliations":[],"preferred":false,"id":426141,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030210,"text":"70030210 - 2007 - Generating an image of dispersive energy by frequency decomposition and slant stacking","interactions":[],"lastModifiedDate":"2012-03-12T17:21:01","indexId":"70030210","displayToPublicDate":"2007-01-01T00:00:00","publicationYear":"2007","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3208,"text":"Pure and Applied Geophysics","active":true,"publicationSubtype":{"id":10}},"title":"Generating an image of dispersive energy by frequency decomposition and slant stacking","docAbstract":"We present a new algorithm for calculating an image of dispersive energy in the frequency-velocity (f-v) domain. The frequency decomposition is first applied to a shot gather in the offset-time domain to stretch impulsive data into pseudo-vibroseis data or frequency-swept data. Because there is a deterministic relationship between frequency and time in a sweep used in the frequency decomposition, the first step theoretically completes the transform from time to frequency. The slant stacking is then performed on the frequency-swept data to complete the transform from offset to velocity. This simple two-step algorithm generates an image of dispersive energy in the f-v domain. The straightforward transform only uses offset information of data so that this algorithm can be applied to data acquired with arbitrary geophone-acquisition geometry. Examples of synthetic and real-world data demonstrate that this algorithm generates accurate images of dispersive energy of the fundamental as well as higher modes. ?? Birkha??user Verlag, Basel, 2007.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Pure and Applied Geophysics","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s00024-007-0204-9","issn":"00334553","usgsCitation":"Xia, J., Xu, Y., and Miller, R., 2007, Generating an image of dispersive energy by frequency decomposition and slant stacking: Pure and Applied Geophysics, v. 164, no. 5, p. 941-956, https://doi.org/10.1007/s00024-007-0204-9.","startPage":"941","endPage":"956","numberOfPages":"16","costCenters":[],"links":[{"id":239291,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":211912,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s00024-007-0204-9"}],"volume":"164","issue":"5","noUsgsAuthors":false,"publicationDate":"2007-04-16","publicationStatus":"PW","scienceBaseUri":"505a154ee4b0c8380cd54d47","contributors":{"authors":[{"text":"Xia, J.","contributorId":63513,"corporation":false,"usgs":true,"family":"Xia","given":"J.","email":"","affiliations":[],"preferred":false,"id":426138,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Xu, Y.","contributorId":47816,"corporation":false,"usgs":true,"family":"Xu","given":"Y.","email":"","affiliations":[],"preferred":false,"id":426137,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Miller, R. 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