Hypotheses in the chelonian literature suggest that in species with sexual size dimorphism, the smaller sex will mature at a smaller size and a younger age than the larger sex, sex ratios should be biased in favor of the earlier maturing sex, and deviations from a 1:1 sex ratio result from maturation of the smaller sex at a younger age. I tested these hypotheses using data collected from 1991 to 1995 on an insular (Egmont Key) population of Florida box turtles, Terrapene carolina bauri. Contrary to predictions, the earlier maturing sex (males) grew to larger sizes than the late maturing sex. Males were significantly larger than females in mean carapace length but not mean body mass. Sex ratios were not balanced, favoring the earlier maturing sex (1.6 males:1 female), but the sex-ratio imbalance did not result from faster maturation of the smaller sex. The imbalance in the sex ratio in Egmont Key's box turtles is not the result of sampling biases; it may result from nest placement. Size-class structure and sex ratios can provide valuable insights into the status and trends of populations of long-lived turtles.
","language":"English","publisher":"NRC Research Press","doi":"10.1139/z97-773","usgsCitation":"Dodd, C., 1997, Population structure and the evolution of sexual size dimorphism and sex ratios in an insular population of Florida box turtles (Terrapene carolina bauri): Canadian Journal of Zoology, v. 75, no. 9, p. 1495-1507, https://doi.org/10.1139/z97-773.","productDescription":"13 p.","startPage":"1495","endPage":"1507","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":566,"text":"Southeast Ecological Science Center","active":true,"usgs":true}],"links":[{"id":231205,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"75","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7d9ae4b0c8380cd7a051","contributors":{"authors":[{"text":"Dodd, C.K. Jr.","contributorId":86286,"corporation":false,"usgs":true,"family":"Dodd","given":"C.K.","suffix":"Jr.","affiliations":[],"preferred":false,"id":385446,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70019103,"text":"70019103 - 1997 - Nowcast model for hazardous material spill prevention and response, San Francisco Bay, California","interactions":[],"lastModifiedDate":"2012-03-12T17:19:15","indexId":"70019103","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Nowcast model for hazardous material spill prevention and response, San Francisco Bay, California","docAbstract":"The National Oceanic and Atmospheric Administration (NOAA) installed the Physical Oceanographic Real-time System (PORTS) in San Francisco Bay, California, to provide real-time observations of tides, tidal currents, and meteorological conditions to, among other purposes, guide hazardous material spill prevention and response. Integrated with nowcast modeling techniques and dissemination of real-time data and the nowcasting results through the Internet on the World Wide Web, emerging technologies used in PORTS for real-time data collection forms a nowcast modeling system. Users can download tides and tidal current distribution in San Francisco Bay for their specific applications and/or for further analysis.","largerWorkTitle":"Oceans Conference Record (IEEE)","conferenceTitle":"Proceedings of the 1997 Oceans Conference. Part 1 (of 2)","conferenceDate":"6 October 1997 through 9 October 1997","conferenceLocation":"Halifax, NS, Can","language":"English","publisher":"IEEE","publisherLocation":"Piscataway, NJ, United States","issn":"01977385","usgsCitation":"Cheng, R.T., Wilmot, W.L., and Galt, J.A., 1997, Nowcast model for hazardous material spill prevention and response, San Francisco Bay, California, in Oceans Conference Record (IEEE), v. 2, Halifax, NS, Can, 6 October 1997 through 9 October 1997, p. 1442-1447.","startPage":"1442","endPage":"1447","numberOfPages":"6","costCenters":[],"links":[{"id":226538,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a68bbe4b0c8380cd73983","contributors":{"authors":[{"text":"Cheng, Ralph T.","contributorId":69134,"corporation":false,"usgs":true,"family":"Cheng","given":"Ralph","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":381683,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wilmot, Wayne L.","contributorId":93210,"corporation":false,"usgs":true,"family":"Wilmot","given":"Wayne","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":381684,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Galt, Jerry A.","contributorId":98051,"corporation":false,"usgs":true,"family":"Galt","given":"Jerry","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":381685,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70019101,"text":"70019101 - 1997 - Thermal regime of the San Andreas fault near Parkfield, California","interactions":[],"lastModifiedDate":"2024-11-06T17:07:59.490964","indexId":"70019101","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","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":"Thermal regime of the San Andreas fault near Parkfield, California","docAbstract":"Knowledge of the temperature variation with depth near the San Andreas fault is vital to understanding the physical processes that occur within the fault zone during earthquakes and creep events. Parkfield is near the southern end of the Coast Ranges segment of the San Andreas fault. This segment has higher mean heat flow than the Cape Mendocino segment to the northwest or the Mojave segment to the southeast. Boreholes were drilled specifically for the U.S. Geological Survey's Parkfield earthquake prediction experiment or converted from other uses at 25 sites within a few kilometers of the fault near Parkfield. These holes, which range in depth from 150 to over 1500m, were intended mainly for the deployment of volumetric strain meters, water-level recorders, and other downhole instruments. Temperature profiles were obtained from all the holes, and heat flow values were estimated from 17 of them. For a number of reasons, including a paucity of thermal conductivity data and rugged local topography, the accuracy of individual determinations was not sufficiently high to document local variations in heat flow. Values range from 54 to 92 mW m−2, with mean and 95% confidence limits of 74±4 mW m−2. This mean is slightly lower than the mean (83±3) of 39 previously published values from the central Coast Ranges, but it is consistent with the overall pattern of elevated heat flow in the Coast Ranges, and it is transitional to the mean of 68±2 mW m−2 that characterizes the Mojave segment of the San Andreas fault immediately to the south. The lack of a heat flow peak near the fault underscores the absence of a frictional thermal anomaly and provides additional support for a very small resolved shear stress parallel to the San Andreas fault and the nearly fault-normal maximum compressive stress observed in this region. Estimates of subsurface thermal conditions indicate that the seismicaseismic transition for the Parkfield segment corresponds to temperatures in the range of 350°–400°C. Increasing heat flow to the northwest of Parkfield corresponds to a transition from locked to creeping sections and to a shallowing of the base of seismicity and confirms the importance of temperature in controlling the thickness of the seismogenic crust. Lateral variations in heat flow do not appear to have any major role in determining the regularity of M5.5–6 earthquakes at Parkfield.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB102iB12p27575","issn":"01480227","usgsCitation":"Sass, J., Williams, C., Lachenbruch, A., Galanis, S., and Grubb, F., 1997, Thermal regime of the San Andreas fault near Parkfield, California: Journal of Geophysical Research B: Solid Earth, v. 102, no. 12, p. 27575-27585, https://doi.org/10.1029/JB102iB12p27575.","productDescription":"11 p.","startPage":"27575","endPage":"27585","numberOfPages":"11","costCenters":[],"links":[{"id":226496,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"102","issue":"12","noUsgsAuthors":false,"publicationDate":"1997-12-10","publicationStatus":"PW","scienceBaseUri":"505bb253e4b08c986b32571d","contributors":{"authors":[{"text":"Sass, J.H.","contributorId":70749,"corporation":false,"usgs":true,"family":"Sass","given":"J.H.","email":"","affiliations":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"preferred":false,"id":381677,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Williams, C.F. 0000-0003-2196-5496","orcid":"https://orcid.org/0000-0003-2196-5496","contributorId":20401,"corporation":false,"usgs":true,"family":"Williams","given":"C.F.","affiliations":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"preferred":false,"id":381675,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lachenbruch, A.H.","contributorId":76737,"corporation":false,"usgs":true,"family":"Lachenbruch","given":"A.H.","affiliations":[],"preferred":false,"id":381678,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Galanis, S.P. Jr.","contributorId":55005,"corporation":false,"usgs":true,"family":"Galanis","given":"S.P.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":381676,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Grubb, F.V.","contributorId":76750,"corporation":false,"usgs":true,"family":"Grubb","given":"F.V.","email":"","affiliations":[],"preferred":false,"id":381679,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70019281,"text":"70019281 - 1997 - Regional landslide-hazard evaluation using landslide slopes, Western Wasatch County, Utah","interactions":[],"lastModifiedDate":"2023-12-17T15:15:34.395133","indexId":"70019281","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1574,"text":"Environmental & Engineering Geoscience","printIssn":"1078-7275","active":true,"publicationSubtype":{"id":10}},"title":"Regional landslide-hazard evaluation using landslide slopes, Western Wasatch County, Utah","docAbstract":"Landsliding has historically been one of the most damaging geologic hazards in western Wasatch County, Utah. Accordingly, we mapped and analyzed landslides (slumps and debris slides) in the area to provide an empirical basis for regional landslide-hazard evaluation. The 336 landslides in the 250-sq-mi (650-km2) area involve 20 geologic units, including Mississippian- to Quaternary-aged rock and unconsolidated deposits. Landsliding in western Wasatch County is characterized by a strong correlation between geologic material and landslide-slope inclination. From a simple statistical analysis of overall slope inclinations of late Holocene landslides, we determined “critical” slope inclinations above which late Holocene landsliding has typically occurred and used these as the primary basis for defining relative landslide hazard. The critical slopes vary for individual geologic units and range from 15 to 50 percent (9°–27°). The critical slope values and landslide locations were used in conjunction with geologic and slope maps to construct qualitative landslide-susceptibility maps for use by county planners. The maps delineate areas of low, moderate, and high relative hazard and indicate where studies should be completed prior to development to evaluate site-specific slope-stability conditions. Critical slopes as determined in this study provide a consistent empirical reference that is useful for evaluating relative landslide hazard and guiding land-use-planning decisions in large, geologically complex areas.
The rate of decay with distance of shear-wave amplitude, computed from 20-sec S-wave spectra, is determined from TERRAscope records of small earthquakes in the greater Los Angeles area. Piecewise log-linear interpolation functions and traditional diminution functions are used to fit spectral decay to a maximum distance of 150 km. Simultaneously, isotropic source and receiver terms are determined. Separate branches of the spectral decay function are found for two categories of source depth: greater than 10 km and less than 10 km. In the hypocentral distance range of 20 to 150 km and in the frequency range of 0.5 to 8.0 Hz, an important result of the investigation is that the horizontal-component decay rate associated with deeper-crustal sources is generally greater than that associated with shallower sources and is greater than that which is estimated using more traditional models of spectral decay with distance. The same behavior generally holds for vertical-component spectra. The variation in apparent attenuation rate with source depth should affect seismic-hazard estimates associated with the rupture of blind thrust faults in the Los Angeles basin and vicinity. The results of the inversions suggest that interpolation function representations of spectral decay are sensitive to perturbations of S-wave amplitude due to crustal reflectors, such as post-critical S-wave arrivals from mid-crustal to deep-crustal velocity interfaces.
Chemical mass balances for sodium, magnesium, chloride, dissolved organic carbon, and oxygen 18 were used to estimate groundwater seepage to and from Williams Lake, Minnesota, over a 15-month period, from April 1991 through June 1992. Groundwater seepage to the lake and seepage from the lake to groundwater were determined independently using a flow net approach using data from water table wells installed as part of the study. Hydrogeological analysis indicated groundwater seepage to the lake accounted for 74% of annual water input to the lake; the remainder came from atmospheric precipitation, as determined from a gage in the watershed and from nearby National Weather Service gages. Seepage from the lake accounted for 69% of annual water losses from the lake; the remainder was removed by evaporation, as determined by the energy budget method. Calculated annual water loss exceeded calculated annual water gain, and this imbalance was double the value of the independently measured decrease in lake volume. Seepage to the lake determined from oxygen 18 was larger (79% of annual water input) than that determined from the flow net approach and made the difference between calculated annual water gain and loss consistent with the independently measured decrease in lake volume. Although the net difference between volume of seepage to the lake and volume of seepage from the lake was 1% of average lake volume, movement of water into and out of the lake by seepage represented an annual exchange of groundwater with the lake equal to 26–27% of lake volume. Estimates of seepage to the lake from sodium, magnesium, chloride, and dissolved organic carbon did not agree with the values determined from flow net approach or oxygen 18. These results indicated the importance of using a combination of hydrogeological and chemical approaches to define volume of seepage to and from Williams Lake and identify uncertainties in chemical fluxes.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/97WR02427","usgsCitation":"LaBaugh, J.W., Winter, T.C., Rosenberry, D.O., Schuster, P.F., Reddy, M.M., and Aiken, G.R., 1997, Hydrological and chemical estimates of the water balance of a closed-basin lake in north central Minnesota: Water Resources Research, v. 33, no. 12, p. 2799-2812, https://doi.org/10.1029/97WR02427.","productDescription":"14 p.","startPage":"2799","endPage":"2812","costCenters":[],"links":[{"id":226431,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Minnesota","otherGeospatial":"Williams Lake","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -94.67612028121948,\n 46.948504487557834\n ],\n [\n -94.66281652450562,\n 46.948504487557834\n ],\n [\n -94.66281652450562,\n 46.9591673117941\n ],\n [\n -94.67612028121948,\n 46.9591673117941\n ],\n [\n -94.67612028121948,\n 46.948504487557834\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"33","issue":"12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a36a9e4b0c8380cd608c3","contributors":{"authors":[{"text":"LaBaugh, James W. 0000-0002-4112-2536 jlabaugh@usgs.gov","orcid":"https://orcid.org/0000-0002-4112-2536","contributorId":1311,"corporation":false,"usgs":true,"family":"LaBaugh","given":"James","email":"jlabaugh@usgs.gov","middleInitial":"W.","affiliations":[{"id":27111,"text":"National Water Quality Program","active":true,"usgs":true},{"id":493,"text":"Office of Ground Water","active":true,"usgs":true}],"preferred":true,"id":383053,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Winter, Thomas C.","contributorId":84736,"corporation":false,"usgs":true,"family":"Winter","given":"Thomas","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":383054,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rosenberry, Donald O. 0000-0003-0681-5641 rosenber@usgs.gov","orcid":"https://orcid.org/0000-0003-0681-5641","contributorId":1312,"corporation":false,"usgs":true,"family":"Rosenberry","given":"Donald","email":"rosenber@usgs.gov","middleInitial":"O.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":383057,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Schuster, Paul F. 0000-0002-8314-1372 pschuste@usgs.gov","orcid":"https://orcid.org/0000-0002-8314-1372","contributorId":1360,"corporation":false,"usgs":true,"family":"Schuster","given":"Paul","email":"pschuste@usgs.gov","middleInitial":"F.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":383056,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Reddy, Michael M. mmreddy@usgs.gov","contributorId":684,"corporation":false,"usgs":true,"family":"Reddy","given":"Michael","email":"mmreddy@usgs.gov","middleInitial":"M.","affiliations":[{"id":145,"text":"Branch of Regional Research-Central Region","active":false,"usgs":true}],"preferred":true,"id":383055,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Aiken, George R. 0000-0001-8454-0984 graiken@usgs.gov","orcid":"https://orcid.org/0000-0001-8454-0984","contributorId":1322,"corporation":false,"usgs":true,"family":"Aiken","given":"George","email":"graiken@usgs.gov","middleInitial":"R.","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":383052,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70019283,"text":"70019283 - 1997 - Late Mesozoic and Cenozoic thermotectonic evolution of the central Brooks Range and adjacent North Slope foreland basin, Alaska: Including fission track results from the Trans-Alaska Crustal Transect (TACT)","interactions":[],"lastModifiedDate":"2024-07-19T15:43:32.357663","indexId":"70019283","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","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":"Late Mesozoic and Cenozoic thermotectonic evolution of the central Brooks Range and adjacent North Slope foreland basin, Alaska: Including fission track results from the Trans-Alaska Crustal Transect (TACT)","docAbstract":"Apatite fission track data are used to evaluate the thermal and tectonic history of the central Brooks Range and the North Slope foreland basin in northern Alaska along the northern leg of the Trans-Alaska Crustal Transect (TACT). Fission track analyses of the detrital apatite grains in most sedimentary units resolve the timing of structures and denudation within the Brooks Range, ranging in scale from the entire mountain range to relatively small-scale folds and faults. Interpretation of the results indicates that rocks exposed within the central Brooks Range cooled rapidly from paleotemperatures 110° to 50°C during discrete episodes at ∼ 100±5 Ma, ∼60±4 Ma, and ∼24±3 Ma, probably in response to kilometer-scale denudation. North of the mountain front, rocks in the southern half of the foreland basin were exposed to maximum paleotemperatures 110°C in the Late Cretaceous to early Paleocene as a result of burial by Upper Jurassic and Cretaceous sedimentary rocks. Rapid cooling from these elevated paleotemperatures also occurred due to distinct episodes of kilometer-scale denudation at ∼60±4 Ma, 46±3 Ma, 35±2 Ma, and ∼24±3 Ma. Combined, the apatite analyses indicate that rocks exposed along the TACT line through the central Brooks Range and foreland basin experienced episodic rapid cooling throughout the Late Cretaceous and Cenozoic in response to at least three distinct kilometer-scale denudation events. Future models explaining orogenic events in northern Alaska must consider these new constraints from fission track thermochronology.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/96JB03411","issn":"01480227","usgsCitation":"O’Sullivan, P.B., Murphy, J., and Blythe, A., 1997, Late Mesozoic and Cenozoic thermotectonic evolution of the central Brooks Range and adjacent North Slope foreland basin, Alaska: Including fission track results from the Trans-Alaska Crustal Transect (TACT): Journal of Geophysical Research B: Solid Earth, v. 102, no. B9, p. 20821-20845, https://doi.org/10.1029/96JB03411.","productDescription":"25 p.","startPage":"20821","endPage":"20845","numberOfPages":"25","costCenters":[],"links":[{"id":480086,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/96jb03411","text":"Publisher Index Page"},{"id":226420,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"102","issue":"B9","noUsgsAuthors":false,"publicationDate":"1997-09-10","publicationStatus":"PW","scienceBaseUri":"505a44f1e4b0c8380cd66ee6","contributors":{"authors":[{"text":"O’Sullivan, P. B.","contributorId":39950,"corporation":false,"usgs":true,"family":"O’Sullivan","given":"P.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":382229,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Murphy, J.M.","contributorId":84760,"corporation":false,"usgs":true,"family":"Murphy","given":"J.M.","email":"","affiliations":[],"preferred":false,"id":382231,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Blythe, A.E.","contributorId":66002,"corporation":false,"usgs":true,"family":"Blythe","given":"A.E.","email":"","affiliations":[],"preferred":false,"id":382230,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70020201,"text":"70020201 - 1997 - Normalizing rainfall/debris-flow thresholds along the U.S. Pacific coast for long-term variations in precipitation climate","interactions":[],"lastModifiedDate":"2012-03-12T17:20:18","indexId":"70020201","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Normalizing rainfall/debris-flow thresholds along the U.S. Pacific coast for long-term variations in precipitation climate","docAbstract":"Broad-scale variations in long-term precipitation climate may influence rainfall/debris-flow threshold values along the U.S. Pacific coast, where both the mean annual precipitation (MAP) and the number of rainfall days (#RDs) are controlled by topography, distance from the coastline, and geographic latitude. Previous authors have proposed that rainfall thresholds are directly proportional to MAP, but this appears to hold only within limited areas (< 1?? latitude), where rainfall frequency (#RDs) is nearly constant. MAP-normalized thresholds underestimate the critical rainfall when applied to areas to the south, where the #RDs decrease, and overestimate threshold rainfall when applied to areas to the north, where the #RDs increase. For normalization between climates where both MAP and #RDs vary significantly, thresholds may best be described as multiples of the rainy-day normal, RDN = MAP/#RDs. Using data from several storms that triggered significant debris-flow activity in southern California, the San Francisco Bay region, and the Pacific Northwest, peak 24-hour rainfalls were plotted against RDN values, displaying a linear relationship with a lower bound at about 14 RDN. RDN ratios in this range may provide a threshold for broad-scale regional forecasting of debris-flow activity.","largerWorkTitle":"International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment, Proceedings","conferenceTitle":"Proceedings of the 1997 1st International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment","conferenceDate":"7 August 1997 through 9 August 1997","conferenceLocation":"San Francisco, CA, USA","language":"English","publisher":"ASCE","publisherLocation":"New York, NY, United States","usgsCitation":"Wilson, R.C., 1997, Normalizing rainfall/debris-flow thresholds along the U.S. Pacific coast for long-term variations in precipitation climate, in International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment, Proceedings, San Francisco, CA, USA, 7 August 1997 through 9 August 1997, p. 32-43.","startPage":"32","endPage":"43","numberOfPages":"12","costCenters":[],"links":[{"id":231512,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a67c6e4b0c8380cd734ab","contributors":{"authors":[{"text":"Wilson, Raymond C. rwilson@usgs.gov","contributorId":5103,"corporation":false,"usgs":true,"family":"Wilson","given":"Raymond","email":"rwilson@usgs.gov","middleInitial":"C.","affiliations":[],"preferred":true,"id":385374,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70020179,"text":"70020179 - 1997 - Evaluation of field and laboratory research on scour at bridge piers in the United States","interactions":[],"lastModifiedDate":"2012-03-12T17:20:15","indexId":"70020179","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Evaluation of field and laboratory research on scour at bridge piers in the United States","docAbstract":"The Federal Highway Administration sponsored a laboratory research at Colorado State University and field data collection with the US Geological Survey, to evaluate the effects of bed material on the depth of scour. Correction factors are compared to include the effect of bed material in the HEC-18 equation. The HEC-18 equation tends to overpredict the observed scour for streams with coarse bed material. The field-based correction factor K4 causes underprediction associated with data collected from other countries.","largerWorkTitle":"Proceedings, Congress of the International Association of Hydraulic Research, IAHR","conferenceTitle":"Proceedings of the 1997 27th Congress of the International Association of Hydraulic Research, IAHR. Part C","conferenceDate":"10 August 1997 through 15 August 1997","conferenceLocation":"San Francisco, CA, USA","language":"English","publisher":"ASCE","publisherLocation":"New York, NY, United States","usgsCitation":"Mueller, D.S., and Jones, J.S., 1997, Evaluation of field and laboratory research on scour at bridge piers in the United States, in Proceedings, Congress of the International Association of Hydraulic Research, IAHR, v. A, San Francisco, CA, USA, 10 August 1997 through 15 August 1997, p. 135-140.","startPage":"135","endPage":"140","numberOfPages":"6","costCenters":[],"links":[{"id":231162,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"A","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0c73e4b0c8380cd52b5a","contributors":{"authors":[{"text":"Mueller, David S. dmueller@usgs.gov","contributorId":1499,"corporation":false,"usgs":true,"family":"Mueller","given":"David","email":"dmueller@usgs.gov","middleInitial":"S.","affiliations":[{"id":502,"text":"Office of Surface Water","active":true,"usgs":true}],"preferred":true,"id":385286,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jones, J. Sterling","contributorId":92814,"corporation":false,"usgs":true,"family":"Jones","given":"J.","email":"","middleInitial":"Sterling","affiliations":[],"preferred":false,"id":385287,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70021118,"text":"70021118 - 1997 - Viscoelastic coupling model of the San Andreas fault along the Big Bend, southern California","interactions":[],"lastModifiedDate":"2024-07-19T14:24:54.355213","indexId":"70021118","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","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":"Viscoelastic coupling model of the San Andreas fault along the Big Bend, southern California","docAbstract":"The big bend segment of the San Andreas fault is the 300-km-long segment in southern California that strikes about N65°W, roughly 25° counterclockwise from the local tangent to the small circle about the Pacific-North America pole of rotation. The broad distribution of deformation of trilateration networks along this segment implies a locking depth of at least 25 km as interpreted by the conventional model of strain accumulation (continuous slip on the fault below the locking depth at the rate of relative plate motion), whereas the observed seismicity and laboratory data on fault strength suggest that the locking depth should be no greater than 10 to 15 km. The discrepancy is explained by the viscoelastic coupling model which accounts for the viscoelastic response of the lower crust. Thus the broad distribution of deformation observed across the big bend segment can be largely associated with the San Andreas fault itself, not subsidiary faults distributed throughout the region. The Working Group on California Earthquake Probabilities [1995] in using geodetic data to estimate the seismic risk in southern California has assumed that strain accumulated off the San Andreas fault is released by earthquakes located off the San Andreas fault. Thus they count the San Andreas contribution to total seismic moment accumulation more than once, leading to an overestimate of the seismicity for magnitude 6 and greater earthquakes in their Type C zones.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/98JB00148","issn":"01480227","usgsCitation":"Savage, J., and Lisowski, M., 1997, Viscoelastic coupling model of the San Andreas fault along the Big Bend, southern California: Journal of Geophysical Research B: Solid Earth, v. 103, no. 4, p. 7281-7292, https://doi.org/10.1029/98JB00148.","productDescription":"12 p.","startPage":"7281","endPage":"7292","numberOfPages":"12","costCenters":[],"links":[{"id":479982,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/98jb00148","text":"Publisher Index Page"},{"id":229658,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"103","issue":"4","noUsgsAuthors":false,"publicationDate":"1998-04-10","publicationStatus":"PW","scienceBaseUri":"505bc283e4b08c986b32abb3","contributors":{"authors":[{"text":"Savage, J.C. 0000-0002-5114-7673","orcid":"https://orcid.org/0000-0002-5114-7673","contributorId":102876,"corporation":false,"usgs":true,"family":"Savage","given":"J.C.","affiliations":[],"preferred":false,"id":388711,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lisowski, M.","contributorId":70381,"corporation":false,"usgs":true,"family":"Lisowski","given":"M.","email":"","affiliations":[],"preferred":false,"id":388710,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70019527,"text":"70019527 - 1997 - Crustal deformation in southern California using SAR interferometry","interactions":[],"lastModifiedDate":"2012-03-12T17:19:20","indexId":"70019527","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1596,"text":"European Space Agency, (Special Publication) ESA SP","active":true,"publicationSubtype":{"id":10}},"title":"Crustal deformation in southern California using SAR interferometry","docAbstract":"By combining pairs of ERS-1/2 SAR images of Southern California spanning long time intervals (1-4 years), we were able to measure the rate of slow deformation processes along faults activated during the Landers 1992 earthquake. Interferograms revealed several centimeters of post-seismic rebound in step-overs of the 1992 break, with a characteristic decay rate of -280 days. We interpreted this process as due to pore fluid flow as pore pressure gradients caused by coseismic stress changes dissipate. The data also revealed evidence of after-slip on different sections of the fault. The southern branches of the 1992 break experienced surface creep producing sharp phase cuts hi the interferometric maps. The same approach was used in the Los Angeles basin, which is currently undergoing NS shortening at a rate of ???8 mm/yr. The tectonic signal in imerferograms of the Los Angeles basin is intermingled with signals due to other sources such as ground subsidence caused by oil and water withdrawal.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"European Space Agency, (Special Publication) ESA SP","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"03796566","usgsCitation":"Peltzer, G., Rosen, P., Rogez, F., and Hudnut, K., 1997, Crustal deformation in southern California using SAR interferometry: European Space Agency, (Special Publication) ESA SP, no. 414 PART 1, p. 545-548.","startPage":"545","endPage":"548","numberOfPages":"4","costCenters":[],"links":[{"id":227916,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"issue":"414 PART 1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fcdce4b0c8380cd4e48b","contributors":{"authors":[{"text":"Peltzer, G.","contributorId":41157,"corporation":false,"usgs":true,"family":"Peltzer","given":"G.","email":"","affiliations":[],"preferred":false,"id":383069,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rosen, P.","contributorId":48920,"corporation":false,"usgs":true,"family":"Rosen","given":"P.","email":"","affiliations":[],"preferred":false,"id":383070,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rogez, F.","contributorId":26458,"corporation":false,"usgs":true,"family":"Rogez","given":"F.","email":"","affiliations":[],"preferred":false,"id":383068,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hudnut, K.","contributorId":92439,"corporation":false,"usgs":true,"family":"Hudnut","given":"K.","affiliations":[],"preferred":false,"id":383071,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70019290,"text":"70019290 - 1997 - Petrography and geochemistry of selected lignite beds in the Gibbons Creek mine (Manning Formation, Jackson Group, Paleocene) of east-central Texas","interactions":[],"lastModifiedDate":"2018-02-01T12:50:02","indexId":"70019290","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2033,"text":"International Journal of Coal Geology","active":true,"publicationSubtype":{"id":10}},"title":"Petrography and geochemistry of selected lignite beds in the Gibbons Creek mine (Manning Formation, Jackson Group, Paleocene) of east-central Texas","docAbstract":"This study examined the petrographic and geochemical characteristics of two lignite beds (3500 and 4500 beds, Manning Formation, Jackson Group, Eocene) that are mined at the Gibbons Creek mine in east-central Texas. The purpose of the study was to identify the relations among sample ash yield, coal petrography, and trace-element concentrations in lignite and adjoining rock layers of the Gibbons Creek mine. Particular interest was given to the distribution of 12 environmentally sensitive trace elements (As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, and U) that have been identified as potentially hazardous air pollutants (HAPs) in the United States Clean Air Act Amendments of 1990. Eleven lignite, floor, and rock parting samples were collected from incremental channel samples of the 3500 and 4500 beds that were exposed in a highwall of pit A3 at the Gibbons Creek mine. Short proximate and ultimate and forms of sulfur analyses were performed on all lignite samples, and lignite and rock samples were analyzed for 60 major, minor and trace elements. Representative splits of all lignite samples were ground and cast into pellets, and polished for petrographic analyses in blue-light fluorescence and reflected white light to determine liptinite, inertinite, and huminite maceral group percentages. The following observations summarize our results and conclusions about the geochemistry, petrography, and sedimentology of the 3500 and 4500 beds of the Gibbons Creek lignite deposit: (1) Weighted average dry (db) ash yield for the two beds is 29.7%, average total sulfur content is 2.6%, and average calorific value is 7832 Btu (18.22 MJ/kg). Ash yields are greatest in the lower bench (59.33% db) of the 3500 bed and in the upper bench of the 4500 bed (74.61% db). (2) For lignite samples (on a whole-coal basis), the distributions of two of the HAPs (Pb and Sb) are positively related to ash yield, probably indicating an inorganic affinity for these elements. By using cluster analysis we found that Be and Cd were poorly associated with ash yield, indicating a possible organic affinity, and that Ni, Se, Hg, U, and Pb cluster with most of the rare-earth elements. (3) The dominance of the crypto-eugelinite maceral subgroup over the crypto-humotelinite subgroup suggests that all Gibbons Creek lignites were subjected to peat-forming conditions (either biogenic or chemical) conducive to the degradation of wood cellular material into matrix gels, or that original plant material was not very woody and was prone to formation of matrix gels. The latter idea is supported by pollen studies of Gibbons Creek lignite beds; results indicate that the peat was derived in part from marsh plants low in wood tissue. (4) The occurrence of siliceous sponge spicules in the lower benches of the 3500 bed suggests the original peat in this part of the bed was deposited in standing, fresh water. (5) The petrographic data indicate that the upper sample interval of the 3500 bed contains more inertinite (3%) than the other samples studied. Increases in inertinite content in the upper part of the 3500 bed may have been associated with alteration of the peat by acids derived from the volcanic ash or could have been caused by fire, oxidation and drying, or biologic alteration of the peat in the paleo-mire.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0166-5162(97)00028-1","usgsCitation":"Warwick, P.D., Crowley, S.S., Ruppert, L.F., and Pontolillo, J., 1997, Petrography and geochemistry of selected lignite beds in the Gibbons Creek mine (Manning Formation, Jackson Group, Paleocene) of east-central Texas: International Journal of Coal Geology, v. 34, no. 3-4, p. 307-326, https://doi.org/10.1016/S0166-5162(97)00028-1.","productDescription":"20 p.","startPage":"307","endPage":"326","costCenters":[],"links":[{"id":226548,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"34","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a779de4b0c8380cd78533","contributors":{"authors":[{"text":"Warwick, Peter D. 0000-0002-3152-7783 pwarwick@usgs.gov","orcid":"https://orcid.org/0000-0002-3152-7783","contributorId":762,"corporation":false,"usgs":true,"family":"Warwick","given":"Peter","email":"pwarwick@usgs.gov","middleInitial":"D.","affiliations":[{"id":241,"text":"Eastern Energy Resources Science Center","active":true,"usgs":true}],"preferred":false,"id":382252,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Crowley, Sharon S.","contributorId":78325,"corporation":false,"usgs":true,"family":"Crowley","given":"Sharon","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":382251,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ruppert, Leslie F. 0000-0002-7453-1061 lruppert@usgs.gov","orcid":"https://orcid.org/0000-0002-7453-1061","contributorId":660,"corporation":false,"usgs":true,"family":"Ruppert","given":"Leslie","email":"lruppert@usgs.gov","middleInitial":"F.","affiliations":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true},{"id":241,"text":"Eastern Energy Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":382253,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Pontolillo, James jpontoli@usgs.gov","contributorId":2033,"corporation":false,"usgs":true,"family":"Pontolillo","given":"James","email":"jpontoli@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":382250,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70019716,"text":"70019716 - 1997 - Effect of flagellates on free-living bacterial abundance in an organically contaminated aquifer","interactions":[],"lastModifiedDate":"2019-02-13T06:20:46","indexId":"70019716","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1621,"text":"FEMS Microbiology Reviews","active":true,"publicationSubtype":{"id":10}},"title":"Effect of flagellates on free-living bacterial abundance in an organically contaminated aquifer","docAbstract":"Little is known about the role of protists in the saturated subsurface. Porous media microcosms containing bacteria and protists, were used to determine whether flagellates from an organically contaminated aquifer could substantively affect the number of free- living bacteria (FLB). When flagellates were present, the 3-40% maximum breakthrough of fluorescent y labelled FLB injected into the microcosms was much lower than the 60-130% observed for killed controls Grazing and clearance rates (3-27 FLB flag-1 h-1 and 12-23 nI flag-1 h-1, respectively) calculated from the data were in the range reported for flagellates in other aqueous environments. The data provide evidence that flagellate bacterivory is an important control on groundwater FLB populations.","language":"English","publisher":"Oxford","doi":"10.1016/S0168-6445(97)00011-9","issn":"01686445","usgsCitation":"Kinner, N., Harvey, R., and Kazmierkiewicz-Tabaka, M., 1997, Effect of flagellates on free-living bacterial abundance in an organically contaminated aquifer: FEMS Microbiology Reviews, v. 20, no. 3-4, p. 249-259, https://doi.org/10.1016/S0168-6445(97)00011-9.","productDescription":"11 p.","startPage":"249","endPage":"259","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":480034,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1016/s0168-6445(97)00011-9","text":"Publisher Index Page"},{"id":228288,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206098,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0168-6445(97)00011-9"}],"volume":"20","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a05dee4b0c8380cd50fd5","contributors":{"authors":[{"text":"Kinner, N.E.","contributorId":29583,"corporation":false,"usgs":true,"family":"Kinner","given":"N.E.","email":"","affiliations":[],"preferred":false,"id":383693,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Harvey, R.W. 0000-0002-2791-8503","orcid":"https://orcid.org/0000-0002-2791-8503","contributorId":11757,"corporation":false,"usgs":true,"family":"Harvey","given":"R.W.","affiliations":[],"preferred":false,"id":383691,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kazmierkiewicz-Tabaka, M.","contributorId":20923,"corporation":false,"usgs":true,"family":"Kazmierkiewicz-Tabaka","given":"M.","email":"","affiliations":[],"preferred":false,"id":383692,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70019219,"text":"70019219 - 1997 - Spring prey use by double-crested cormorants on the Penobscot River, Maine, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:19:10","indexId":"70019219","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3731,"text":"Waterbirds","onlineIssn":"19385390","printIssn":"15244695","active":true,"publicationSubtype":{"id":10}},"title":"Spring prey use by double-crested cormorants on the Penobscot River, Maine, USA","docAbstract":"We analyzed 2 sets of data for Double-crested Cormorant (Phalacrocorax auritus) stomach contents (including esophageal contents) that were collected from April through June of 1986-1988 (N = 580) and 1992-1993 (N = 200) on the Penobscot River, Maine. Our objectives were to examine temporal and spatial variation in the spring diet and estimate the importance of Atlantic salmon (Salmo salar) smolts to the cormorant diet. We analyzed stomach contents relative to samples from 3 river sections: 5 mainstem dams collectively, above the head of tide, and free-flowing areas above and below the head of tide. Between years composition of taxa lists were compared (P = 0.05) relative to time and river section. We estimated taxon importance for data collected during 1992-1993 by ranking taxa according to 3 statistics: frequency of occurrence, mean percent volume, and numerical abundance. Data from 1986-88 were analyzed by frequency of occurrence only. Across the 3 river sections, the number of prey species recovered from cormorant stomachs increased from 15 in late April to at least 31 through May. Cormorants collected above the head of tide consumed 12 fish species (including freshwater, anadromous, and catadromous types), whereas birds collected below the head of tide consumed 28 freshwater and seasonally-available estuarine, marine benthic, and pelagic species. Salmon smolts were not recovered from stomachs collected in April, rare in stomach samples during the first week of June, and absent from the diet thereafter. In contrast, smolts were among the 5 most frequently occurring (1986-88) and highest ranking (1992-1993) prey taxa across the 3 river sections through May.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Waterbirds","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"07386028","usgsCitation":"Blackwell, B., Krohn, W., Dube, N., and Godin, A., 1997, Spring prey use by double-crested cormorants on the Penobscot River, Maine, USA: Waterbirds, v. 20, no. 1, p. 77-86.","startPage":"77","endPage":"86","numberOfPages":"10","costCenters":[],"links":[{"id":226824,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"20","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9622e4b08c986b31b2fa","contributors":{"authors":[{"text":"Blackwell, B.F.","contributorId":45039,"corporation":false,"usgs":true,"family":"Blackwell","given":"B.F.","email":"","affiliations":[],"preferred":false,"id":382030,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Krohn, W.B.","contributorId":64355,"corporation":false,"usgs":true,"family":"Krohn","given":"W.B.","email":"","affiliations":[],"preferred":false,"id":382032,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dube, N.R.","contributorId":31924,"corporation":false,"usgs":true,"family":"Dube","given":"N.R.","email":"","affiliations":[],"preferred":false,"id":382029,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Godin, A.J.","contributorId":48680,"corporation":false,"usgs":true,"family":"Godin","given":"A.J.","email":"","affiliations":[],"preferred":false,"id":382031,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70020142,"text":"70020142 - 1997 - Application of two direct runoff prediction methods in Puerto Rico","interactions":[],"lastModifiedDate":"2024-05-08T14:33:33.484403","indexId":"70020142","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2341,"text":"Journal of Hydrologic Engineering","active":true,"publicationSubtype":{"id":10}},"title":"Application of two direct runoff prediction methods in Puerto Rico","docAbstract":"Two methods for predicting direct runoff from rainfall data were applied to several basins and the resulting hydrographs compared to measured values. The first method uses a geomorphology-based unit hydrograph to predict direct runoff through its convolution with the excess rainfall hyetograph. The second method shows how the resulting hydraulic routing flow equation from a kinematic wave approximation is solved using a spectral method based on the matrix representation of the spatial derivative with Chebyshev collocation and a fourth-order Runge-Kutta time discretization scheme. The calibrated Green-Ampt (GA) infiltration parameters are obtained by minimizing the sum, over several rainfall events, of absolute differences between the total excess rainfall volume computed from the GA equations and the total direct runoff volume computed from a hydrograph separation technique. The improvement made in predicting direct runoff using a geomorphology-based unit hydrograph with the ephemeral and perennial stream network instead of the strictly perennial stream network is negligible. The hydraulic routing scheme presented here is highly accurate in predicting the magnitude and time of the hydrograph peak although the much faster unit hydrograph method also yields reasonable results.
","language":"English","publisher":"ASCE","doi":"10.1061/(ASCE)1084-0699(1997)2:1(10)","issn":"10840699","usgsCitation":"Sepulveda, N., 1997, Application of two direct runoff prediction methods in Puerto Rico: Journal of Hydrologic Engineering, v. 2, no. 1, p. 10-17, https://doi.org/10.1061/(ASCE)1084-0699(1997)2:1(10).","productDescription":"8 p.","startPage":"10","endPage":"17","numberOfPages":"8","costCenters":[],"links":[{"id":228042,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"2","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ecbfe4b0c8380cd49465","contributors":{"authors":[{"text":"Sepulveda, N.","contributorId":56805,"corporation":false,"usgs":true,"family":"Sepulveda","given":"N.","email":"","affiliations":[],"preferred":false,"id":385181,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70019730,"text":"70019730 - 1997 - Evaluation of unconfined-aquifer parameters from pumping test data by nonlinear least squares","interactions":[],"lastModifiedDate":"2019-02-13T06:15:40","indexId":"70019730","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Evaluation of unconfined-aquifer parameters from pumping test data by nonlinear least squares","docAbstract":"Nonlinear least squares (NLS) with automatic differentiation was used to estimate aquifer parameters from drawdown data obtained from published pumping tests conducted in homogeneous, water-table aquifers. The method is based on a technique that seeks to minimize the squares of residuals between observed and calculated drawdown subject to bounds that are placed on the parameter of interest. The analytical model developed by Neuman for flow to a partially penetrating well of infinitesimal diameter situated in an infinite, homogeneous and anisotropic aquifer was used to obtain calculated drawdown. NLS was first applied to synthetic drawdown data from a hypothetical but realistic aquifer to demonstrate that the relevant hydraulic parameters (storativity, specific yield, and horizontal and vertical hydraulic conductivity) can be evaluated accurately. Next the method was used to estimate the parameters at three field sites with widely varying hydraulic properties. NLS produced unbiased estimates of the aquifer parameters that are close to the estimates obtained with the same data using a visual curve-matching approach. Small differences in the estimates are a consequence of subjective interpretation introduced in the visual approach.","language":"English","publisher":"Elsevier","doi":"10.1016/S0022-1694(96)03101-0","issn":"00221694","usgsCitation":"Heidari, M., and Moench, A., 1997, Evaluation of unconfined-aquifer parameters from pumping test data by nonlinear least squares: Journal of Hydrology, v. 192, no. 1-4, p. 300-313, https://doi.org/10.1016/S0022-1694(96)03101-0.","productDescription":"14 p.","startPage":"300","endPage":"313","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":227805,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205998,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0022-1694(96)03101-0"}],"volume":"192","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0d02e4b0c8380cd52dac","contributors":{"authors":[{"text":"Heidari, M.","contributorId":26430,"corporation":false,"usgs":true,"family":"Heidari","given":"M.","email":"","affiliations":[],"preferred":false,"id":383731,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Moench, A.","contributorId":12638,"corporation":false,"usgs":true,"family":"Moench","given":"A.","email":"","affiliations":[],"preferred":false,"id":383730,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70020141,"text":"70020141 - 1997 - A new approach for analyzing bird densities from variable circular-plot counts","interactions":[],"lastModifiedDate":"2012-03-12T17:19:19","indexId":"70020141","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2990,"text":"Pacific Science","active":true,"publicationSubtype":{"id":10}},"title":"A new approach for analyzing bird densities from variable circular-plot counts","docAbstract":"An approach for calculating bird densities from variable circular-plot counts is described. The approach differs from previous methods in that data from several surveys are pooled and detection distances are adjusted as if all distances were recorded by a single observer under a given set of field conditions. Adjustments for covariates that affect detection distances such as observer, weather, time of day, and vegetation type are made using coefficients calculated by multiple linear regression. The effective area surveyed under standard conditions is calculated from the pooled data set and then used to determine the effective area surveyed at each sampling station under the actual conditions when the station was sampled. The method was validated in two field studies where the density of birds could be determined by independent methods. Computer software for entering and analyzing data by this method is described.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Pacific Science","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"00308870","usgsCitation":"Fancy, S., 1997, A new approach for analyzing bird densities from variable circular-plot counts: Pacific Science, v. 51, no. 1, p. 107-114.","startPage":"107","endPage":"114","numberOfPages":"8","costCenters":[],"links":[{"id":228041,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"51","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e49be4b0c8380cd4676c","contributors":{"authors":[{"text":"Fancy, S.G.","contributorId":8957,"corporation":false,"usgs":true,"family":"Fancy","given":"S.G.","affiliations":[],"preferred":false,"id":385180,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70019231,"text":"70019231 - 1997 - Benthic boundary layer processes in the Lower Florida Keys","interactions":[],"lastModifiedDate":"2022-11-14T15:30:31.407711","indexId":"70019231","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1742,"text":"Geo-Marine Letters","active":true,"publicationSubtype":{"id":10}},"title":"Benthic boundary layer processes in the Lower Florida Keys","docAbstract":"This special issue of Geo-Marine Letters, \"Benthic Boundary Layer Processes in the Lower Florida Keys,\" includes 12 papers that present preliminary results from the Key West Campaign. The Dry Tortugas and Marquesas Keys test sites were selected by a group of 115 scientists and technicians to study benthic boundary layer processes in a carbonate environment controlled by bioturbation and biogeochemical processes. Major activities included remote sediment classification; high-frequency acoustic scattering experiments; sediment sampling for radiological, geotechnical, biological, biogeochemical, physical, and geoacoustic studies; and hydrodynamic studies using an instrumented tetrapod. All these data are being used to improve our understanding of the effects of environmental processes on sediment structure and behavior.
","language":"English","publisher":"Springer","doi":"10.1007/s003670050032","usgsCitation":"Lavoie, D.L., Richardson, M.D., and Holmes, C., 1997, Benthic boundary layer processes in the Lower Florida Keys: Geo-Marine Letters, v. 17, no. 4, p. 232-236, https://doi.org/10.1007/s003670050032.","productDescription":"5 p.","startPage":"232","endPage":"236","numberOfPages":"5","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":226326,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Florida","otherGeospatial":"Dry Tortugas, Marquesas Keys","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -81.86887794417834,\n 24.813884982383343\n ],\n [\n -83.1597001594551,\n 24.813884982383343\n ],\n [\n -83.1597001594551,\n 24.37971577423204\n ],\n [\n -81.86887794417834,\n 24.37971577423204\n ],\n [\n -81.86887794417834,\n 24.813884982383343\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"17","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f0b3e4b0c8380cd4a87d","contributors":{"authors":[{"text":"Lavoie, D. L.","contributorId":46640,"corporation":false,"usgs":true,"family":"Lavoie","given":"D.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":382081,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Richardson, M. D.","contributorId":88094,"corporation":false,"usgs":true,"family":"Richardson","given":"M.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":382082,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Holmes, C.","contributorId":33067,"corporation":false,"usgs":true,"family":"Holmes","given":"C.","affiliations":[],"preferred":false,"id":382080,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70019732,"text":"70019732 - 1997 - Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution","interactions":[],"lastModifiedDate":"2019-02-13T05:48:05","indexId":"70019732","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution","docAbstract":"Fluid saturation, particle-size distribution, and porosity measurements were obtained from 269 core samples collected from six boreholes along a 90-m transect at a subregion of a crude-oil spill site, the north pool, near Bemidji, Minnesota. The oil saturation data, collected 11 years after the spill, showed an irregularly shaped oil body that appeared to be affected by sediment spatial variability. The particle-size distribution data were used to estimate the permeability (k) and retention curves for each sample. An additional 344 k estimates were obtained from samples previously collected at the north pool. The 613 k estimates were distributed bimodal lognormally with the two population distributions corresponding to the two predominant lithologies: a coarse glacial outwash deposit and fine-grained interbedded lenses. A two-step geostatistical approach was used to generate a conditioned realization of k representing the bimodal heterogeneity. A cross-sectional multiphase flow model was used to simulate the flow of oil and water in the presence of air along the north pool transect for an 11-year period. The inclusion of a representation of the bimodal aquifer heterogeneity was crucial for reproduction of general features of the observed oil body. If the bimodal heterogeneity was characterized, hysteresis did not have to be incorporated into the model because a hysteretic effect was produced by the sediment spatial variability. By revising the relative permeability functional relation, an improved reproduction of the observed oil saturation distribution was achieved. The inclusion of water table fluctuations in the model did not significantly affect the simulated oil saturation distribution.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/97WR00857","usgsCitation":"Dillard, L.A., Essaid, H.I., and Herkelrath, W.N., 1997, Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution: Water Resources Research, v. 33, no. 7, p. 1617-1632, https://doi.org/10.1029/97WR00857.","productDescription":"16 p.","startPage":"1617","endPage":"1632","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":480116,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/97wr00857","text":"Publisher Index Page"},{"id":227843,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"33","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6057e4b0c8380cd713b3","contributors":{"authors":[{"text":"Dillard, Leslie A.","contributorId":189405,"corporation":false,"usgs":false,"family":"Dillard","given":"Leslie","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":383736,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Essaid, Hedeff I. 0000-0003-0154-8628 hiessaid@usgs.gov","orcid":"https://orcid.org/0000-0003-0154-8628","contributorId":2284,"corporation":false,"usgs":true,"family":"Essaid","given":"Hedeff","email":"hiessaid@usgs.gov","middleInitial":"I.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":383735,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Herkelrath, William N. 0000-0002-6149-5524 wnherkel@usgs.gov","orcid":"https://orcid.org/0000-0002-6149-5524","contributorId":2612,"corporation":false,"usgs":true,"family":"Herkelrath","given":"William","email":"wnherkel@usgs.gov","middleInitial":"N.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":383737,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70019237,"text":"70019237 - 1997 - Harmonic Analysis of Sedimentary Cyclic Sequences in Kansas, Midcontinent, USA","interactions":[],"lastModifiedDate":"2013-03-01T15:15:46","indexId":"70019237","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2700,"text":"Mathematical Geology","active":true,"publicationSubtype":{"id":10}},"title":"Harmonic Analysis of Sedimentary Cyclic Sequences in Kansas, Midcontinent, USA","docAbstract":"Several stratigraphic sequences in the Upper Carboniferous (Pennsylvanian) in Kansas (Midcontinent, USA) were analyzed quantitatively for periodic repetitions. The sequences were coded by lithologic type into strings of datasets. The strings then were analyzed by an adaptation of a one-dimensional Fourier transform analysis and examined for evidence of periodicity. The method was tested using different states in coding to determine the robustness of the method and data. The most persistent response is in multiples of 8-10 ft (2.5-3.0 m) and probably is dependent on the depositional thickness of the original lithologic units. Other cyclicities occurred in multiples of the basic frequency of 8-10 with persistent ones at 22 and 30 feet (6.5-9.0 m) and large ones at 80 and 160 feet (25-50 m). These levels of thickness relate well to the basic cyclothem and megacyclothem as measured on outcrop. We propose that this approach is a suitable one for analyzing cyclic events in the stratigraphic record.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Mathematical Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Springer","doi":"10.1023/A:1022301417788","issn":"08828121","usgsCitation":"Merriam, D.F., and Robinson, J., 1997, Harmonic Analysis of Sedimentary Cyclic Sequences in Kansas, Midcontinent, USA: Mathematical Geology, v. 29, no. 8, p. 953-962, https://doi.org/10.1023/A:1022301417788.","startPage":"953","endPage":"962","numberOfPages":"10","costCenters":[],"links":[{"id":268638,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1022301417788"},{"id":226418,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"29","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2f77e4b0c8380cd5cdeb","contributors":{"authors":[{"text":"Merriam, D. F.","contributorId":63175,"corporation":false,"usgs":true,"family":"Merriam","given":"D.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":382105,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Robinson, J.E.","contributorId":53100,"corporation":false,"usgs":true,"family":"Robinson","given":"J.E.","email":"","affiliations":[],"preferred":false,"id":382104,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70019530,"text":"70019530 - 1997 - Estimation of αL, velocity, Kd and confidence limits from tracer injection test data","interactions":[],"lastModifiedDate":"2024-07-11T16:16:50.16129","indexId":"70019530","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3825,"text":"Groundwater","active":true,"publicationSubtype":{"id":10}},"displayTitle":"Estimation of αL, velocity, Kd and confidence limits from tracer injection test data","title":"Estimation of αL, velocity, Kd and confidence limits from tracer injection test data","docAbstract":"Bromide and boron were used as tracers during an injection experiment conducted at an artificial recharge facility near Stanton, Texas. The Ogallala aquifer at the Stanton site represents a heterogeneous alluvial environment and provides the opportunity to report scale dependent dispersivities at observation distances of 2 to 15 m in this setting. Values of longitudinal dispersivities are compared with other published values. Water samples were collected at selected depths both from piezometers and from fully screened observation wells at radii of 2, 5, 10 and 15 m. An exact analytical solution is used to simulate the concentration breakthrough curves and estimate longitudinal dispersivities and velocity parameters. Greater confidence can be placed on these data because the estimated parameters are error bounded using the bootstrap method. The non-conservative behavior of boron transport in clay rich sections of the aquifer were quantified with distribution coefficients by using bromide as a conservative reference tracer.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.1997.tb00179.x","issn":"0017467X","usgsCitation":"Broermann, J., Bassett, R., Weeks, E.P., and Borgstrom, M., 1997, Estimation of αL, velocity, Kd and confidence limits from tracer injection test data: Groundwater, v. 35, no. 6, p. 1066-1076, https://doi.org/10.1111/j.1745-6584.1997.tb00179.x.","productDescription":"11 p.","startPage":"1066","endPage":"1076","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":430979,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Texas","otherGeospatial":"northern Texas","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -102.74414062499999,\n 33.284619968887675\n ],\n [\n -99.84374999999999,\n 33.284619968887675\n ],\n [\n -99.84374999999999,\n 36.66841891894786\n ],\n [\n -102.74414062499999,\n 36.66841891894786\n ],\n [\n -102.74414062499999,\n 33.284619968887675\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"35","issue":"6","noUsgsAuthors":false,"publicationDate":"2005-08-04","publicationStatus":"PW","scienceBaseUri":"505a0b74e4b0c8380cd5271e","contributors":{"authors":[{"text":"Broermann, James","contributorId":98481,"corporation":false,"usgs":true,"family":"Broermann","given":"James","email":"","affiliations":[],"preferred":false,"id":383082,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bassett, R.L.","contributorId":13233,"corporation":false,"usgs":true,"family":"Bassett","given":"R.L.","email":"","affiliations":[],"preferred":false,"id":383079,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Weeks, Edwin P. epweeks@usgs.gov","contributorId":2576,"corporation":false,"usgs":true,"family":"Weeks","given":"Edwin","email":"epweeks@usgs.gov","middleInitial":"P.","affiliations":[],"preferred":true,"id":383081,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Borgstrom, Mark","contributorId":31538,"corporation":false,"usgs":true,"family":"Borgstrom","given":"Mark","email":"","affiliations":[],"preferred":false,"id":383080,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70019308,"text":"70019308 - 1997 - Efficacy of a vacuum benthos sampler for collecting demersal fish eggs from gravel substratum","interactions":[],"lastModifiedDate":"2023-10-12T15:15:36.603689","indexId":"70019308","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1471,"text":"Ecology of Freshwater Fish","active":true,"publicationSubtype":{"id":10}},"title":"Efficacy of a vacuum benthos sampler for collecting demersal fish eggs from gravel substratum","docAbstract":"We used two densities of eggs (low=900 eggs/m2; high=5100 eggs/m2) in laboratory experiments to estimate the recovery efficiency of the Brown benthos sampler for collecting fish eggs from gravel substrate and to determine if differences (e. g., 5-fold) in egg density in the substratum could be detected with the sampler. The mean egg recovery efficiency of the sampler in the low and high density treatments was 30% (SE=8.7) and 35% (SE=3.8), respectively. The difference between the treatment means was not significant. Therefore, data from the two treatments were pooled and used to estimate the recovery efficiency of the sampler (32.7%, SE=4.4). However, we were able to detect a 5× difference in the number of eggs collected with the sampler between the two treatments. Our estimate of the recovery efficiency of the sampler for collecting fish eggs was less than those reported for the sampler's efficiency for collecting benthic macroinvertebrates. The low recovery efficiency of the sampler for collecting fish eggs does not lessen the utility of the device. Rather, ecologists planning to use the sampler must estimate the recovery efficiency of target fauna, especially if density estimates are to be calculated, because recovery efficiency probably is less than 100%.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1600-0633.1997.tb00166.x","usgsCitation":"Ruetz, C.R., and Jennings, C., 1997, Efficacy of a vacuum benthos sampler for collecting demersal fish eggs from gravel substratum: Ecology of Freshwater Fish, v. 6, no. 4, p. 241-244, https://doi.org/10.1111/j.1600-0633.1997.tb00166.x.","productDescription":"4 p.","startPage":"241","endPage":"244","numberOfPages":"4","costCenters":[],"links":[{"id":226828,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"6","issue":"4","noUsgsAuthors":false,"publicationDate":"2006-06-30","publicationStatus":"PW","scienceBaseUri":"505a0856e4b0c8380cd51aa1","contributors":{"authors":[{"text":"Ruetz, Carl R. III","contributorId":62765,"corporation":false,"usgs":true,"family":"Ruetz","given":"Carl","suffix":"III","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":382307,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jennings, Cecil A.","contributorId":38504,"corporation":false,"usgs":true,"family":"Jennings","given":"Cecil A.","affiliations":[],"preferred":false,"id":382306,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70020140,"text":"70020140 - 1997 - Carbon isotopes in biological carbonates: Respiration and photosynthesis","interactions":[],"lastModifiedDate":"2023-12-14T23:20:30.71411","indexId":"70020140","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Carbon isotopes in biological carbonates: Respiration and photosynthesis","docAbstract":"Respired carbon dioxide is an important constituent in the carbonates of most air breathing animals but is much less important in the carbonates of most aquatic animals. This difference is illustrated using carbon isotope data from freshwater and terrestrial snails, ahermatypic corals, and chemoautotrophic and methanotrophic pelecypods. Literature data from fish otoliths and bird and mammal shell and bone carbonates are also considered.
Environmental CO2/O2 ratios appear to be the major controlling variable. Atmospheric CO2/O2 ratios are about thirty times lower than in most natural waters, hence air breathing animals absorb less environmental CO2 in the course of obtaining 02. Tissue CO2 therefore, does not isotopically equilibrate with environmental CO2 as thoroughly in air breathers as in aquatic animals, and this is reflected in skeletal carbonates. Animals having efficient oxygen transport systems, such as vertebrates, also accumulate more respired CO2 in their tissues.
Photosynthetic corals calcify mainly during the daytime when photosynthetic CO2 uptake is several times faster than respiratory CO2 release. Photosynthesis, therefore, affects skeletal δ13C more strongly than does respiration. Corals also illustrate how “metabolic” effects on skeletal isotopic composition can be estimated, despite the presence of much larger “kinetic” isotope effects.