Hydrogenetic ferromanganese crusts reflect the chemical conditions of the sewater from which they formed. Fine-scale geochemical analysis of crust layers in combination with age determinations can therefore be used to investigate paleoceanographic changes which are recorded in geochemical gradients in the crusts. At Tropic seamount (off northwest Africa), uniform crust growth influenced by terrigenous input from the African continent occurred during approximately the past 12 Ma. Phosphatization of these crusts is minor. In contrast, crusts from Lion seamount, located between Madeira and the Portuguese coast, display a much more variable growth history. A pronounced increase in Ni, Cu, and Zn is observed in some intervals of the crusts, which probably reflects increased surface productivity. A thick older phosphatized generation occurs in many samples. Hydrographic profiles indicate that Mediterranean outflow water (MOW) may play an important role in the composition of these crusts.10Be dating of one sample confirms that the interruption of the MOW during the Messinian salinity crisis (6.2–5 Ma ago) resulted in changes in element composition. Sr-isotope dating of the apatite phase of the old crust generation has been carried out to obtain a minimum age for the older generation of Atlantic crusts and to determine whether crust phosphatization in the Atlantic can be related to phosphatization episodes recorded in Pacific crusts. The preliminary data show that the old phosphatized crust generation might be as old as approximately 30–40 Ma.
","language":"English","publisher":"Springer","doi":"10.1007/BF02369011","usgsCitation":"Koschinsky, A., Halbach, P., Hein, J., and Mangini, A., 1996, Ferromanganese crusts as indicators for paleoceanographic events in the NE Atlantic: Geologische Rundschau, v. 85, no. 3, p. 567-576, https://doi.org/10.1007/BF02369011.","productDescription":"10 p.","startPage":"567","endPage":"576","numberOfPages":"10","costCenters":[],"links":[{"id":227054,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Northeast Atlantic","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -30.25,\n 40\n ],\n [\n -30.25,\n 18\n ],\n [\n -1,\n 18\n ],\n [\n -1,\n 40\n ],\n [\n -30.25,\n 40\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"85","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0f86e4b0c8380cd5392e","contributors":{"authors":[{"text":"Koschinsky, A.","contributorId":42724,"corporation":false,"usgs":true,"family":"Koschinsky","given":"A.","affiliations":[],"preferred":false,"id":378665,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Halbach, P.","contributorId":101396,"corporation":false,"usgs":true,"family":"Halbach","given":"P.","affiliations":[],"preferred":false,"id":378667,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hein, J.R. 0000-0002-5321-899X","orcid":"https://orcid.org/0000-0002-5321-899X","contributorId":61429,"corporation":false,"usgs":true,"family":"Hein","given":"J.R.","affiliations":[],"preferred":false,"id":378666,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Mangini, A.","contributorId":22101,"corporation":false,"usgs":true,"family":"Mangini","given":"A.","email":"","affiliations":[],"preferred":false,"id":378664,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70018661,"text":"70018661 - 1996 - The Springdale, Utah, landslide: An extraordinary event","interactions":[],"lastModifiedDate":"2023-12-17T15:18:49.508245","indexId":"70018661","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"The Springdale, Utah, landslide: An extraordinary event","docAbstract":"The most dramatic geologic effect of the M-5.7 St. George, Utah earthquake of 2 September 1992 was the triggering of the 14,000,000-m3 Springdale, Utah landslide. The roughly 10 m of landslide movement destroyed three houses, threatened several condominiums, disrupted utility lines, and temporarily closed the southwest entrance to Zion National Park. The seismic triggering of this landslide is puzzling because its distance from the earthquake epicenter, 44 km, is much greater than the farthest distance (18 km) at which similar landslides have been triggered in worldwide earthquakes of the same magnitude. Other Colorado Plateau earthquakes also have produced landslides far beyond worldwide distance limits, which suggests that regional variations in ground-shaking attenuation may require different landslide-triggering distance limits for different seismotectonic regions. Slope stability analysis and historical records of landslide movement suggest that the Springdale landslide was only slightly above limit-equilibrium conditions at the time of the earthquake. Dynamic stability analysis using Newmark's permanent-displacement method indicates coseismic landslide displacement of only 1-8 cm; this rather modest displacement probably induced enough deformation in the montmorillonitic clays along the failure surface to reduce shear strength and destabilize the slide, which continued to move for several hours after the earthquake.","language":"English","publisher":"Environmental Engineering Geologists","doi":"10.2113/gseegeosci.II.2.137","issn":"10787275","usgsCitation":"Jibson, R., and Harp, E.L., 1996, The Springdale, Utah, landslide: An extraordinary event: Environmental & Engineering Geoscience, v. 2, no. 2, p. 137-150, https://doi.org/10.2113/gseegeosci.II.2.137.","productDescription":"14 p.","startPage":"137","endPage":"150","numberOfPages":"14","costCenters":[],"links":[{"id":227002,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Utah","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -113.35586933298275,\n 37.55683192885232\n ],\n [\n -113.35586933298275,\n 36.971021423655\n ],\n [\n -111.99356464548232,\n 36.971021423655\n ],\n [\n -111.99356464548232,\n 37.55683192885232\n ],\n [\n -113.35586933298275,\n 37.55683192885232\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"2","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba904e4b08c986b321fe1","contributors":{"authors":[{"text":"Jibson, R.W.","contributorId":8467,"corporation":false,"usgs":true,"family":"Jibson","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":380357,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Harp, E. L.","contributorId":59026,"corporation":false,"usgs":true,"family":"Harp","given":"E.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":380358,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018748,"text":"70018748 - 1996 - Denitrification and nitrogen transport in a coastal aquifer receiving wastewater discharge","interactions":[],"lastModifiedDate":"2012-03-12T17:19:25","indexId":"70018748","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Denitrification and nitrogen transport in a coastal aquifer receiving wastewater discharge","docAbstract":"Denitrification and nitrogen transport were quantified in a sandy glacial aquifer receiving wastewater from a septage-treatment facility on Cape Cod, MA. The resulting groundwater plume contained high concentrations of NO3- (32 mg of NL-1), total dissolved nitrogen (40.5 mg of N L-1), and dissolved organic carbon (1.9 mg of C L-1) and developed a central anoxic zone after 17 months of effluent discharge. Denitrifying activity was measured using four approaches throughout the major biogeochemical zones of the plume. Three approaches that maintained the structure of aquifer materials yielded comparable rates: acetylene block in intact sediment cores, 9.6 ng of N cm-3 d-1 (n = 61); in situ N2 production, 3.0 ng of N cm-3 d-1 (n = 11); and in situ NO3- depletion, 7.1 ng of N cm-3 d-1 (n = 3). In contrast, the mixing of aquifer materials using a standard slurry method yielded rates that were more than 15-fold higher (150 ng of N cm-3 d-1, n = 16) than other methods. Concentrations and ??15N of groundwater and effluent N2, NO3-, and NH4+ were consistent with the lower rates of denitrification determined by the intact-core or in situ methods. These methods and a plumewide survey of excess N2 indicate that 2-9% of the total mass of fixed nitrogen recharged to the anoxic zone of the plume was denitrified during the 34-month study period. Denitrification was limited by organic carbon (not NO3-) concentrations, as evidenced by a nitrate and carbon addition experiment, the correlation of denitrifying activity with in situ concentrations of dissolved organic carbon, and the assessments of available organic carbon in plume sediments. Carbon limitation is consistent with the observed conservative transport of 85-96% of the nitrate in the anoxic zone. Although denitrifying activity removed a significant amount (46250 kg) of fixed nitrogen during transport, the effects of aquifer denitrification on the nitrogen load to receiving ecosystems are likely to be small (<10%).","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Science and Technology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1021/es950366p","issn":"0013936X","usgsCitation":"DeSimone, L., and Howes, B., 1996, Denitrification and nitrogen transport in a coastal aquifer receiving wastewater discharge: Environmental Science & Technology, v. 30, no. 4, p. 1152-1162, https://doi.org/10.1021/es950366p.","startPage":"1152","endPage":"1162","numberOfPages":"11","costCenters":[],"links":[{"id":205962,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es950366p"},{"id":227664,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"30","issue":"4","noUsgsAuthors":false,"publicationDate":"1996-03-26","publicationStatus":"PW","scienceBaseUri":"5059fe98e4b0c8380cd4edf8","contributors":{"authors":[{"text":"DeSimone, L.A.","contributorId":79132,"corporation":false,"usgs":true,"family":"DeSimone","given":"L.A.","email":"","affiliations":[],"preferred":false,"id":380645,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Howes, B.L.","contributorId":41854,"corporation":false,"usgs":true,"family":"Howes","given":"B.L.","email":"","affiliations":[],"preferred":false,"id":380644,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018758,"text":"70018758 - 1996 - Seismic reflection evidence against a shallow detachment beneath Yucca Mountain, Nevada","interactions":[],"lastModifiedDate":"2012-03-12T17:19:27","indexId":"70018758","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Seismic reflection evidence against a shallow detachment beneath Yucca Mountain, Nevada","docAbstract":"Intermediate-depth seismic reflection profile across Crater Flat and Yucca Mountain is obtained. The aim of the seismic profiling are discrimination the subsurface geometry of faults and imaging of the boundary between the pre-Tertiary sedimentary strata and the Miocene volcanic rocks of Yucca Mountain. Of major interest is the existence and geometry of a postulated west-dipping detachment fault beneath Yucca Mountain. These reflection profiles provide critical input to efforts to evaluate tectonic models, probabilistic seismic hazards, and potential volcanic hazards near Yucca Mountain, site of investigations for a potential permanent repository for high-level nuclear waste.","largerWorkTitle":"High Level Radioactive Waste Management - Proceedings of the Annual International Conference","conferenceTitle":"Proceedings of the 1996 7th Annual International Conference on High Radioactive Waste Management","conferenceDate":"29 April 1996 through 3 May 1996","conferenceLocation":"Las Vegas, NV, USA","language":"English","publisher":"ASCE","publisherLocation":"New York, NY, United States","usgsCitation":"Brocher, T.M., and Hunter, W.C., 1996, Seismic reflection evidence against a shallow detachment beneath Yucca Mountain, Nevada, in High Level Radioactive Waste Management - Proceedings of the Annual International Conference, Las Vegas, NV, USA, 29 April 1996 through 3 May 1996, p. 148-150.","startPage":"148","endPage":"150","numberOfPages":"3","costCenters":[],"links":[{"id":227088,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8b40e4b08c986b3176d4","contributors":{"authors":[{"text":"Brocher, Thomas M. 0000-0002-9740-839X brocher@usgs.gov","orcid":"https://orcid.org/0000-0002-9740-839X","contributorId":262,"corporation":false,"usgs":true,"family":"Brocher","given":"Thomas","email":"brocher@usgs.gov","middleInitial":"M.","affiliations":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"preferred":true,"id":380669,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hunter, W. Clay","contributorId":75704,"corporation":false,"usgs":true,"family":"Hunter","given":"W.","email":"","middleInitial":"Clay","affiliations":[],"preferred":false,"id":380670,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018139,"text":"70018139 - 1996 - Tectonic model explaining divergent contraction directions along the Cascadia subduction margin, Washington","interactions":[],"lastModifiedDate":"2024-01-20T01:33:25.151527","indexId":"70018139","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1796,"text":"Geology","active":true,"publicationSubtype":{"id":10}},"title":"Tectonic model explaining divergent contraction directions along the Cascadia subduction margin, Washington","docAbstract":"Differential motion across the central Cascadia subduction boundary in Washington results in a complex pattern of folds and faults within the shelf and onshore parts of the accretionary margin. Faults and folds above a coastal, north-northwest–trending thrust system provide evidence of ongoing subduction-related contraction. South of this coastal thrust system many fold axes and thrust faults trend east-northeast, in the direction of convergence. These structures are not consistent with a simple subduction system undergoing northeastward convergence. This deformation, adjacent to the boundary between the subduction complex and the Siletz terrane, may be driven by relative convergence between the northward-translating Siletz terrane and the subduction complex. The regional pattern of modern uplift rates is consistent with ongoing north-south contraction across this boundary and the north-south compressional stress field in the area.
The response of water in the unsaturated zone to seasonal changes of temperature (T) is determined analytically using the theory of nonisothermal water transport in porous media, and the solutions are tested against field observations of moisture potential and bomb fallout isotopic (36Cl and 3H) concentrations. Seasonally varying land surface temperatures and the resulting subsurface temperature gradients induce thermal vapor diffusion. The annual mean vertical temperature gradient is close to zero; however, the annual mean thermal vapor flux is downward, because the temperature‐dependent vapor diffusion coefficient is larger, on average, during downward diffusion (occurring at high T) than during upward diffusion (low T). The annual mean thermal vapor flux is shown to decay exponentially with depth; the depth (about 1 m) at which it decays to e−1of its surface value is one half of the corresponding decay depth for the amplitude of seasonal temperature changes. This depth‐dependent annual mean flux is effectively a source of water, which must be balanced by a flux divergence associated with other transport processes. In a relatively humid environment the liquid fluxes greatly exceed the thermal vapor fluxes, so such a balance is readily achieved without measurable effect on the dynamics of water in the unsaturated zone. However, if the mean vertical water flux through the unsaturated zone is very small (<1 mm y−1), as it may be at many locations in a desert landscape, the thermal vapor flux must be balanced mostly by a matric‐potential‐induced upward flux of water. This return flux may include both vapor and liquid components. Below any near‐surface zone of weather‐related fluctuations of matric potential, maintenance of this upward flux requires an increase with depth in the annual mean matric potential; this theoretical prediction is supported by long‐term field measurements in the Chihuahuan Desert. The analysis also makes predictions, confirmed by the field observations, regarding the seasonal variations of matric potential at a given depth. The conceptual model of unsaturated zone water transport developed here implies the possibility of near‐surface trapping of any aqueous constituent introduced at the surface.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/95WR03489","usgsCitation":"Milly, P., 1996, Effects of thermal vapor diffusion on seasonal dynamics of water in the unsaturated zone: Water Resources Research, v. 32, no. 3, p. 509-518, https://doi.org/10.1029/95WR03489.","productDescription":"10 p.","startPage":"509","endPage":"518","costCenters":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"links":[{"id":227386,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"32","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a080ae4b0c8380cd51947","contributors":{"authors":[{"text":"Milly, Paul C.D. 0000-0003-4389-3139 cmilly@usgs.gov","orcid":"https://orcid.org/0000-0003-4389-3139","contributorId":2119,"corporation":false,"usgs":true,"family":"Milly","given":"Paul C.D.","email":"cmilly@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":false,"id":379872,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70018519,"text":"70018519 - 1996 - Elemental composition and molecular structure of Botryococcus alginite in Westphalian cannel coals from Kentucky","interactions":[],"lastModifiedDate":"2012-03-12T17:19:24","indexId":"70018519","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2958,"text":"Organic Geochemistry","active":true,"publicationSubtype":{"id":10}},"title":"Elemental composition and molecular structure of Botryococcus alginite in Westphalian cannel coals from Kentucky","docAbstract":"Botryococcus-derived alginites from the Westphalian Skyline, No. 5 Block, Leatherwood (eastern Kentucky) and Breckinridge (western Kentucky) coal beds have been analyzed for elemental composition and functional group distribution using an electron microprobe and micro-FTIR, respectively. The alginites from Kentucky show a carbon range of 81.6 to 92% and oxygen content of 3.5 to 9.5%. Sulphur content ranges from 0.66 to 0.84% and Fe, Si, Al and Ca occur in minor quantities. FTIR analysis demonstrates dominant CH2, CH3 bands and subordinate aromatic carbon in all alginites. The major differences between alginites are in the ratios of CH2 and CH3 groups and ratios between aromatic bands in the out-of-plane region. These differences suggest that, although the ancient Botryococcus derives from a selective preservation of a resistant polymer, it undergoes molecular and some elemental changes through the rank equivalent to vitrinite reflectance of 0.5-0.85%. Other differences, such as intensities of ether bridges and those of carboxyl/carbonyl groups, are attributed to differences in depositional environments.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Organic Geochemistry","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/0146-6380(96)00027-7","issn":"01466380","usgsCitation":"Mastalerz, M., and Hower, J., 1996, Elemental composition and molecular structure of Botryococcus alginite in Westphalian cannel coals from Kentucky: Organic Geochemistry, v. 24, no. 3, p. 301-308, https://doi.org/10.1016/0146-6380(96)00027-7.","startPage":"301","endPage":"308","numberOfPages":"8","costCenters":[],"links":[{"id":205931,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0146-6380(96)00027-7"},{"id":227521,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"24","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a08bae4b0c8380cd51c47","contributors":{"authors":[{"text":"Mastalerz, Maria","contributorId":78065,"corporation":false,"usgs":true,"family":"Mastalerz","given":"Maria","affiliations":[],"preferred":false,"id":379912,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hower, J.C.","contributorId":100541,"corporation":false,"usgs":true,"family":"Hower","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":379913,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018521,"text":"70018521 - 1996 - Key sources of uncertainty in QUAL2E model of passaic river","interactions":[],"lastModifiedDate":"2024-05-23T14:36:52.663818","indexId":"70018521","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2501,"text":"Journal of Water Resources Planning and Management","active":true,"publicationSubtype":{"id":10}},"title":"Key sources of uncertainty in QUAL2E model of passaic river","docAbstract":"Application of stream water-quality models in decision making has been hampered by a lack of data appropriate for minimization of model-simulation uncertainty. A method for determining data needed to reduce model-prediction uncertainty is illustrated in this paper. First-order reliability analysis is applied to determine (1) the model parameters that significantly affect model-prediction uncertainty; and (2) the constituents for which model-prediction uncertainty is unacceptable. Additional data are required to reduce uncertainty in the parameters that significantly affect constituents with high prediction uncertainty and consequently in model prediction. The method is demonstrated for multiconstituent water-quality modeling on the Passaic River in New Jersey applying QUAL2E. The model-prediction uncertainty of dissolved oxygen, biochemical oxygen demand, ammonia, and chlorphyll a is considered. For this example, only the reaeration rate and the algal maximum-specific-growth rate contribute significant uncertainty to model prediction. The effect of reducing the uncertainty in the reaeration rate and algal maximum-specific-growth rate on the uncertainty on predicted dissolved oxygen and chlorphyll a, respectively, is demonstrated.
","language":"English","publisher":"ASCE","doi":"10.1061/(ASCE)0733-9496(1996)122:2(105)","issn":"07339496","usgsCitation":"Melching, C., and Yoon, C., 1996, Key sources of uncertainty in QUAL2E model of passaic river: Journal of Water Resources Planning and Management, v. 122, no. 2, p. 105-113, https://doi.org/10.1061/(ASCE)0733-9496(1996)122:2(105).","productDescription":"9 p.","startPage":"105","endPage":"113","numberOfPages":"9","costCenters":[],"links":[{"id":227565,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"122","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a407ce4b0c8380cd64dd5","contributors":{"authors":[{"text":"Melching, Charles S.","contributorId":23973,"corporation":false,"usgs":true,"family":"Melching","given":"Charles S.","affiliations":[],"preferred":false,"id":379926,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Yoon, C.G.","contributorId":12217,"corporation":false,"usgs":true,"family":"Yoon","given":"C.G.","email":"","affiliations":[],"preferred":false,"id":379925,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018523,"text":"70018523 - 1996 - Chemical and isotopic characteristics of fluids along the cameroon volcanic line, cameroon","interactions":[],"lastModifiedDate":"2019-04-17T14:14:47","indexId":"70018523","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2147,"text":"Journal of African Earth Sciences","active":true,"publicationSubtype":{"id":10}},"title":"Chemical and isotopic characteristics of fluids along the cameroon volcanic line, cameroon","docAbstract":"Results of the chemical and isotopic analysis of the water and gases discharged from volcanic crater lakes and soda springs located along the Cameroon Volcanic Line were used to characterize and infer their genetic relationships. Variations in the solute compositions of the waters indicate the dominant influence of silicate hydrolysis. Na+ (40-95%) constitutes the major cation in the springs while Fe2+ + Mg2+ (70%) dominate in the CO2-rich lakes. The principal anion is HCO3 (>90%), except in the coastal springs where Cl predominates. Lakes Nyos and Monoun have Fe-Mg-Ca-HCO3 type signatures; the soda springs are essentially Na-HCO3 type, while all other lakes show similar ionic compositions to dilute surface waters. Dissolved gases show essentially CO2 (>90%), with small amounts of Ar and N2, while CH4 constitutes the principal component in the non-gassy lakes. Active volcanic gases are generally absent, except in the Lobe spring with detectable H2S. Stable isotope ratio evidence indicates that the bicarbonate waters are essentially of meteoric origin. CO2 (??13C = -2 to -8???) and He (3He/4He = 1 to 5.6Ra) infer a mantle contribution to the total CO2. CH4 has a biogenic source, while Ar and N2 are essentially atmospheric in origin, but mixing is quite common.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of African Earth Sciences","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/0899-5362(96)00025-5","issn":"08995362","usgsCitation":"Tanyileke, G., Kusakabe, M., and Evans, W.C., 1996, Chemical and isotopic characteristics of fluids along the cameroon volcanic line, cameroon: Journal of African Earth Sciences, v. 22, no. 4, p. 433-441, https://doi.org/10.1016/0899-5362(96)00025-5.","startPage":"433","endPage":"441","numberOfPages":"9","costCenters":[{"id":615,"text":"Volcano Hazards Program","active":true,"usgs":true}],"links":[{"id":227567,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205948,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0899-5362(96)00025-5"}],"volume":"22","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f540e4b0c8380cd4c137","contributors":{"authors":[{"text":"Tanyileke, G.Z.","contributorId":20486,"corporation":false,"usgs":true,"family":"Tanyileke","given":"G.Z.","email":"","affiliations":[],"preferred":false,"id":379929,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kusakabe, M.","contributorId":94437,"corporation":false,"usgs":true,"family":"Kusakabe","given":"M.","email":"","affiliations":[],"preferred":false,"id":379930,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Evans, William C.","contributorId":104903,"corporation":false,"usgs":true,"family":"Evans","given":"William","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":379931,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":1013473,"text":"1013473 - 1996 - Results of Bayesian methods depend on details of implementation: An example of estimating salmon escapement goals","interactions":[],"lastModifiedDate":"2023-10-31T11:04:09.458816","indexId":"1013473","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1661,"text":"Fisheries Research","active":true,"publicationSubtype":{"id":10}},"title":"Results of Bayesian methods depend on details of implementation: An example of estimating salmon escapement goals","docAbstract":"Bayesian methods have been proposed to estimate optimal escapement \r\n goals, using both knowledge about physical determinants of salmon \r\n productivity and stock-recruitment data. The Bayesian approach has \r\n several advantages over many traditional methods for estimating stock \r\n productivity: it allows integration of information from diverse \r\n sources and provides a framework for decision-making that takes into \r\n account uncertainty reflected in the data. However, results can be \r\n critically dependent on details of implementation of this approach. \r\n For instance, unintended and unwarranted confidence about \r\n stock-recruitment relationships can arise if the range of relationships \r\n examined is too narrow, if too few discrete alternatives are \r\n considered, or if data are contradictory. This unfounded confidence \r\n can result in a suboptimal choice of a spawning escapement goal.","language":"English","publisher":"Elsevier","doi":"10.1016/0165-7836(95)00405-X","usgsCitation":"Adkison, M.D., and Peterman, R.M., 1996, Results of Bayesian methods depend on details of implementation: An example of estimating salmon escapement goals: Fisheries Research, v. 25, p. 155-170, https://doi.org/10.1016/0165-7836(95)00405-X.","productDescription":"16 p.","startPage":"155","endPage":"170","numberOfPages":"16","costCenters":[{"id":106,"text":"Alaska Biological Science Center","active":false,"usgs":true}],"links":[{"id":129683,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a19e4b07f02db6059fc","contributors":{"authors":[{"text":"Adkison, Milo D.","contributorId":100791,"corporation":false,"usgs":false,"family":"Adkison","given":"Milo","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":318685,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Peterman, R. M.","contributorId":83871,"corporation":false,"usgs":false,"family":"Peterman","given":"R.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":318684,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018722,"text":"70018722 - 1996 - Air pollutant intrusion into the Wieliczka Salt Mine","interactions":[],"lastModifiedDate":"2012-03-12T17:19:27","indexId":"70018722","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Air pollutant intrusion into the Wieliczka Salt Mine","docAbstract":"The Wieliczka Salt Mine World Cultural Heritage Site contains many rock salt sculptures that are threatened by water vapor condensation from the mine ventilation air. Gaseous and particulate air pollutant concentrations have been measured both outdoors and within the Wieliczka Salt Mine, along with pollutant deposition fluxes to surfaces within the mine. One purpose of these measurements was to determine whether or not low deliquescence point ionic materials (e.g., NH4NO3) are accumulating on surfaces to an extent that would exacerbate the water vapor condensation problems in the mine. It was found that pollutant gases including SO2 and HNO3 present in outdoor air are removed rapidly and almost completely from the air within the mine by deposition to surfaces. Sulfur isotope analyses confirm the accumulation of air pollutant-derived sulfur in liquid dripping from surfaces within the mine. Particle deposition onto interior surfaces in the mine is apparent, with resulting soiling of some of those sculptures that have been carved from translucent rock salt. Water accumulation by salt sculpture surfaces was studied both experimentally and by approximate thermodynamic calculations. Both approaches suggest that the pollutant deposits on the sculpture surfaces lower the relative humidity (RH) at which a substantial amount of liquid water will accumulate by 1% to several percent. The extraordinarily low SO2 concentrations within the mine may explain the apparent success of a respiratory sanatorium located deep within the mine.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Science and Technology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1021/es950306j","issn":"0013936X","usgsCitation":"Salmon, L., Cass, G., Kozlowski, R., Hejda, A., Spiker, E., and Bates, A., 1996, Air pollutant intrusion into the Wieliczka Salt Mine: Environmental Science & Technology, v. 30, no. 3, p. 872-880, https://doi.org/10.1021/es950306j.","startPage":"872","endPage":"880","numberOfPages":"9","costCenters":[],"links":[{"id":205888,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es950306j"},{"id":227313,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"30","issue":"3","noUsgsAuthors":false,"publicationDate":"1996-02-26","publicationStatus":"PW","scienceBaseUri":"5059e918e4b0c8380cd480c3","contributors":{"authors":[{"text":"Salmon, L.G.","contributorId":62351,"corporation":false,"usgs":true,"family":"Salmon","given":"L.G.","email":"","affiliations":[],"preferred":false,"id":380550,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cass, G.R.","contributorId":91257,"corporation":false,"usgs":true,"family":"Cass","given":"G.R.","email":"","affiliations":[],"preferred":false,"id":380551,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kozlowski, R.","contributorId":42727,"corporation":false,"usgs":true,"family":"Kozlowski","given":"R.","email":"","affiliations":[],"preferred":false,"id":380549,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hejda, A.","contributorId":101032,"corporation":false,"usgs":true,"family":"Hejda","given":"A.","email":"","affiliations":[],"preferred":false,"id":380552,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Spiker, E.C.","contributorId":103275,"corporation":false,"usgs":true,"family":"Spiker","given":"E.C.","affiliations":[],"preferred":false,"id":380553,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Bates, A. L. 0000-0002-4875-4675","orcid":"https://orcid.org/0000-0002-4875-4675","contributorId":42357,"corporation":false,"usgs":true,"family":"Bates","given":"A. L.","affiliations":[],"preferred":false,"id":380548,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70018525,"text":"70018525 - 1996 - Extended history of a 3.5 Ga trondhjemitic gneiss, Wyoming Province, USA: Evidence from U-Pb systematics in zircon","interactions":[],"lastModifiedDate":"2025-06-26T14:44:35.840965","indexId":"70018525","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3112,"text":"Precambrian Research","active":true,"publicationSubtype":{"id":10}},"title":"Extended history of a 3.5 Ga trondhjemitic gneiss, Wyoming Province, USA: Evidence from U-Pb systematics in zircon","docAbstract":"The Beartooth-Bighorn magmatic zone (BBMZ) and the Montana metasedimentary province (MMP) are two major subprovinces of the Archean Wyoming province. In the northwestern Beartooth Mountains, these subprovinces are separated by a structurally, lithologically and metamorphically complex assemblage of lithotectonic units that include: (1) a strongly deformed complex of trondhjemitic gneiss and interlayered amphibolites; and (2) an amphibolite facies mafic unit that occurs in a nappe that structurally overlies the gneiss complex. Zircons from a trondhjemitic blastomylonite in the gneiss complex yield concordant U-Pb ages of 3.5 Ga, establishing it as the oldest rock yet documented in the Wyoming province. Two younger events are also recorded by zircons in this rock: (1) an apparently protracted period of high-grade metamorphism and/or intrusion of additional magmas at ∼ 3.25 Ga; and (2) growth of hydrothermal zircon at ∼ 2.55 Ga, apparently associated with ductile deformation that immediately preceded structural emplacement of the gneiss. Although this latter event appears confined to areas along the BBMZ-MMP boundary, evidence of ∼ 3.25 Ga igneous activity is found in the overlying amphibolite (3.24 Ga) and throughout the MMP. These data suggest that this boundary first developed as a major intracratonic zone of displacement at or before 3.25 Ga. The limited occurrences of 2.8 Ga magmatic activity in the MMP suggest that it had a controlling influence on late Archean magmatism as well.
","language":"English","publisher":"Elsevier","doi":"10.1016/0301-9268(95)00067-4","issn":"03019268","usgsCitation":"Mueller, P., Wooden, J.L., Mogk, D., Nutman, A., and Williams, I., 1996, Extended history of a 3.5 Ga trondhjemitic gneiss, Wyoming Province, USA: Evidence from U-Pb systematics in zircon: Precambrian Research, v. 78, no. 1-3, p. 41-52, https://doi.org/10.1016/0301-9268(95)00067-4.","productDescription":"12 p.","startPage":"41","endPage":"52","numberOfPages":"12","costCenters":[],"links":[{"id":227610,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"78","issue":"1-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0e3ee4b0c8380cd53373","contributors":{"authors":[{"text":"Mueller, P.A.","contributorId":86117,"corporation":false,"usgs":true,"family":"Mueller","given":"P.A.","email":"","affiliations":[],"preferred":false,"id":379937,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wooden, J. L.","contributorId":58678,"corporation":false,"usgs":true,"family":"Wooden","given":"J.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":379935,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mogk, D.W.","contributorId":61575,"corporation":false,"usgs":true,"family":"Mogk","given":"D.W.","affiliations":[],"preferred":false,"id":379936,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Nutman, A.P.","contributorId":16177,"corporation":false,"usgs":true,"family":"Nutman","given":"A.P.","affiliations":[],"preferred":false,"id":379933,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Williams, I.S.","contributorId":20094,"corporation":false,"usgs":true,"family":"Williams","given":"I.S.","email":"","affiliations":[],"preferred":false,"id":379934,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":1013474,"text":"1013474 - 1996 - Assessing variability and trends in Arctic sea ice distribution using satellite data","interactions":[],"lastModifiedDate":"2024-01-25T17:12:33.313987","indexId":"1013474","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Assessing variability and trends in Arctic sea ice distribution using satellite data","docAbstract":"Trends in the annual minimum, minimum monthly-mean, and the sea ice extent at the end of August were investigated for the Barents and western Kara Seas and adjacent parts of the Arctic Ocean during 1966 to 1994 using data from Russian ice maps (1974-1994), Kosmos-Okean and ALMAZ SAR satellite series (1984-1994), and published literature. Four definitions of sea ice extent were examined based on thresholds of ice concentration: >90%, >70%, >40% and >10% (E1, E2, E3, and E4, respectively). Root-mean-square differences between sea ice maps and satellite-image sea ice classifications for coincident areas were subjected to Monte-Carlo analyses to construct confidence intervals for the 20-year ice-map trends. With probability p=0.8, the average 20-year change in the minimum monthly-mean sea ice extent (followed in brackets by the average change in the absolute annual minimum ice extent) was between 30-60% [19-71%], 29-61% [15-67%], 31-63%[18-69%] and 18-48% [7-55%] in the Barents sea; (-24)-(-4)% [(-25)-(12)%], (-27)-(-9)% [(-34)-(-4)%], (-32)-(-15)% [(-39)-(-9)%] and (-33)-(-15)%[(-38)-(-8)%] in the western Kara sea; and (-3)-19% [(-8)-29%], (-4)-18% [(-11)-26%,] (-6)-16% [(-11)(-24)%] and (-7)-15% [(-12)-24%] in the combined Barents and Kara Seas, for sea ice concentration E1-E4, respectively. Including published data from 1966-1983, the trend in minimum monthly-mean sea ice extent for the combined 30-year period showed an average increasing of 11.8% in the Barents Sea and of 47.4% reduction in the western Kara Sea; sea ice extent at the end of August showed an average reduction of 4.7% in the Barents Sea.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Proceedings, IGARSS 1996","largerWorkSubtype":{"id":10,"text":"Journal Article"},"conferenceTitle":"IEEE International Symposium on Geoscience and Remote Sensing (IGARSS)","conferenceDate":"May 31, 1996","conferenceLocation":"Lincoln, NE","language":"English","publisher":"IEEE","doi":"10.1109/IGARSS.1996.516429","usgsCitation":"Belchansky, G., Mordvintsev, I.N., and Douglas, D., 1996, Assessing variability and trends in Arctic sea ice distribution using satellite data, in Proceedings, IGARSS 1996, Lincoln, NE, May 31, 1996, p. 642-644, https://doi.org/10.1109/IGARSS.1996.516429.","productDescription":"3 p.","startPage":"642","endPage":"644","numberOfPages":"3","costCenters":[{"id":106,"text":"Alaska Biological Science Center","active":false,"usgs":true}],"links":[{"id":131224,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49e4e4b07f02db5e5e39","contributors":{"authors":[{"text":"Belchansky, G. I.","contributorId":24301,"corporation":false,"usgs":false,"family":"Belchansky","given":"G. I.","affiliations":[],"preferred":false,"id":318687,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mordvintsev, Ilia N.","contributorId":91044,"corporation":false,"usgs":false,"family":"Mordvintsev","given":"Ilia","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":318688,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Douglas, David C. 0000-0003-0186-1104 ddouglas@usgs.gov","orcid":"https://orcid.org/0000-0003-0186-1104","contributorId":150115,"corporation":false,"usgs":true,"family":"Douglas","given":"David C.","email":"ddouglas@usgs.gov","affiliations":[{"id":114,"text":"Alaska Science Center","active":true,"usgs":true},{"id":117,"text":"Alaska Science Center Biology WTEB","active":true,"usgs":true},{"id":116,"text":"Alaska Science Center Biology MFEB","active":true,"usgs":true}],"preferred":true,"id":318686,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":1013475,"text":"1013475 - 1996 - Population delineation of polar bears using satellite collar data","interactions":[],"lastModifiedDate":"2017-08-29T21:29:03","indexId":"1013475","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1450,"text":"Ecological Applications","active":true,"publicationSubtype":{"id":10}},"title":"Population delineation of polar bears using satellite collar data","docAbstract":"To produce reliable estimates of the size or vital rates of a given population, it is important that the boundaries of the population under study are clearly defined. This is particularly critical for large, migratory animals where levels of sustainable harvest are based on these estimates, and where small errors may have serious long-term consequences for the population. Once populations are delineated, rates of exchange between adjacent populations can be determined and accounted/corrected for when calculating abundance (e.g., based on mark-recapture data). Using satellite radio-collar locations for polar bears in the western Canadian Arctic, we illustrate one approach to delineating wildlife populations that integrates cluster analysis methods for determining group membership with home range plotting procedures to define spatial utilization. This approach is flexible with respect to the specific procedures used and provides an objective and quantitative basis for defining population boundaries.","language":"English","publisher":"Wiley","doi":"10.2307/2269574","usgsCitation":"Bethke, R., Taylor, M.K., Amstrup, S.C., and Messier, F., 1996, Population delineation of polar bears using satellite collar data: Ecological Applications, v. 6, no. 1, p. 311-317, https://doi.org/10.2307/2269574.","productDescription":"pp. 311-317","startPage":"311","endPage":"317","numberOfPages":"7","costCenters":[{"id":106,"text":"Alaska Biological Science Center","active":false,"usgs":true}],"links":[{"id":134388,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"6","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4aa7e4b07f02db6670bc","contributors":{"authors":[{"text":"Bethke, R.","contributorId":30594,"corporation":false,"usgs":true,"family":"Bethke","given":"R.","email":"","affiliations":[],"preferred":false,"id":318690,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Taylor, Mitchell K.","contributorId":131049,"corporation":false,"usgs":false,"family":"Taylor","given":"Mitchell","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":318692,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Amstrup, Steven C.","contributorId":67034,"corporation":false,"usgs":false,"family":"Amstrup","given":"Steven","email":"","middleInitial":"C.","affiliations":[{"id":13182,"text":"Polar Bears International","active":true,"usgs":false}],"preferred":false,"id":318691,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Messier, Francois","contributorId":179093,"corporation":false,"usgs":false,"family":"Messier","given":"Francois","email":"","affiliations":[{"id":13248,"text":"University of Saskatchewan","active":true,"usgs":false}],"preferred":false,"id":318689,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70018135,"text":"70018135 - 1996 - Detailed observations of California foreshock sequences: Implications for the earthquake initiation process","interactions":[],"lastModifiedDate":"2024-11-12T17:37:32.413921","indexId":"70018135","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Detailed observations of California foreshock sequences: Implications for the earthquake initiation process","docAbstract":"We find that foreshocks provide clear evidence for an extended nucleation process before some earthquakes. In this study, we examine in detail the evolution of six California foreshock sequences, the 1986 Mount Lewis (ML = 5.5), the 1986 Chalfant (ML = 6.4), the 1986 Stone Canyon (ML = 4.7), the 1990 Upland (ML = 5.2), the 1992 Joshua Tree (MW = 6.1), and the 1992 Landers (MW = 7.3) sequence. Typically, uncertainties in hypocentral parameters are too large to establish the geometry of foreshock sequences and hence to understand their evolution. However, the similarity of location and focal mechanisms for the events in these sequences leads to similar foreshock waveforms that we cross correlate to obtain extremely accurate relative locations. We use these results to identify small-scale fault zone structures that could influence nucleation and to determine the stress evolution leading up to the mainshock. In general, these foreshock sequences are not compatible with a cascading failure nucleation model in which the foreshocks all occur on a single fault plane and trigger the mainshock by static stress transfer. Instead, the foreshocks seem to concentrate near structural discontinuities in the fault and may themselves be a product of an aseismic nucleation process. Fault zone heterogeneity may also be important in controlling the number of foreshocks, i.e., the stronger the heterogeneity, the greater the number of foreshocks. The size of the nucleation region, as measured by the extent of the foreshock sequence, appears to scale with mainshock moment in the same manner as determined independently by measurements of the seismic nucleation phase. We also find evidence for slip localization as predicted by some models of earthquake nucleation.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/96JB02269","issn":"01480227","usgsCitation":"Dodge, D., Beroza, G., and Ellsworth, W., 1996, Detailed observations of California foreshock sequences: Implications for the earthquake initiation process: Journal of Geophysical Research B: Solid Earth, v. 101, no. B10, p. 22371-22392, https://doi.org/10.1029/96JB02269.","productDescription":"22 p.","startPage":"22371","endPage":"22392","numberOfPages":"22","costCenters":[],"links":[{"id":227671,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"101","issue":"B10","noUsgsAuthors":false,"publicationDate":"1996-10-10","publicationStatus":"PW","scienceBaseUri":"5059ff53e4b0c8380cd4f11c","contributors":{"authors":[{"text":"Dodge, D.A.","contributorId":68324,"corporation":false,"usgs":true,"family":"Dodge","given":"D.A.","email":"","affiliations":[],"preferred":false,"id":378652,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Beroza, G. C.","contributorId":95626,"corporation":false,"usgs":false,"family":"Beroza","given":"G. C.","affiliations":[],"preferred":false,"id":378653,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ellsworth, W.L.","contributorId":48541,"corporation":false,"usgs":true,"family":"Ellsworth","given":"W.L.","email":"","affiliations":[],"preferred":false,"id":378651,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018527,"text":"70018527 - 1996 - Pattern recognition analysis and classification modeling of selenium-producing areas","interactions":[],"lastModifiedDate":"2024-04-16T23:05:03.611478","indexId":"70018527","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2210,"text":"Journal of Chemometrics","active":true,"publicationSubtype":{"id":10}},"title":"Pattern recognition analysis and classification modeling of selenium-producing areas","docAbstract":"Established chemometric and geochemical techniques were applied to water quality data from 23 National Irrigation Water Quality Program (NIWQP) study areas in the Western United States. These techniques were applied to the NIWQP data set to identify common geochemical processes responsible for mobilization of selenium and to develop a classification model that uses major-ion concentrations to identify areas that contain elevated selenium concentrations in water that could pose a hazard to water fowl. Pattern recognition modeling of the simple-salt data computed with the SNORM geochemical program indicate three principal components that explain 95% of the total variance. A three-dimensional plot of PC 1, 2 and 3 scores shows three distinct clusters that correspond to distinct hydrochemical facies denoted as facies 1, 2 and 3. Facies 1 samples are distinguished by water samples without the CaCO3 simple salt and elevated concentrations of NaCl, CaSO4, MgSO4 and Na2SO4 simple salts relative to water samples in facies 2 and 3. Water samples in facies 2 are distinguished from facies 1 by the absence of the MgSO4 simple salt and the presence of the CaCO3 simple salt. Water samples in facies 3 are similar to samples in facies 2, with the absence of both MgSO4 and CaSO4 simple salts. Water samples in facies 1 have the largest selenium concentration (10 μg l−1), compared to a median concentration of 2·0 μg l−1 and less than 1·0 μg l−1 for samples in facies 2 and 3. A classification model using the soft independent modeling by class analogy (SIMCA) algorithm was constructed with data from the NIWQP study areas. The classification model was successful in identifying water samples with a selenium concentration that is hazardous to some species of water-fowl from a test data set comprised of 2,060 water samples from throughout Utah and Wyoming. Application of chemometric and geochemical techniques during data synthesis analysis of multivariate environmental databases from other national-scale environmental programs such as the NIWQP could also provide useful insights for addressing ‘real world’ environmental problems.
","language":"English","publisher":"Wiley","doi":"10.1002/(SICI)1099-128X(199607)10:4<309::AID-CEM426>3.0.CO;2-X","issn":"08869383","usgsCitation":"Naftz, D.L., 1996, Pattern recognition analysis and classification modeling of selenium-producing areas: Journal of Chemometrics, v. 10, no. 4, p. 309-324, https://doi.org/10.1002/(SICI)1099-128X(199607)10:4<309::AID-CEM426>3.0.CO;2-X.","productDescription":"16 p.","startPage":"309","endPage":"324","numberOfPages":"16","costCenters":[],"links":[{"id":227650,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"10","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a75b5e4b0c8380cd77cc3","contributors":{"authors":[{"text":"Naftz, D. L.","contributorId":40624,"corporation":false,"usgs":true,"family":"Naftz","given":"D.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":379942,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70018530,"text":"70018530 - 1996 - Is internal friction friction?","interactions":[],"lastModifiedDate":"2024-02-12T12:13:54.679111","indexId":"70018530","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Is internal friction friction?","docAbstract":"Mogi [1974] proposed a simple model of the incipient rupture surface to explain the Coulomb failure criterion. We show here that this model can plausibly be extended to explain the Mohr failure criterion. In Mogi's model the incipient rupture surface immediately before fracture consists of areas across which material integrity is maintained (intact areas) and areas across which it is not (cracks). The strength of the incipient rupture surface is made up of the inherent strength of the intact areas plus the frictional resistance to sliding offered by the cracked areas. Although the coefficient of internal friction (slope of the strength versus normal stress curve) depends upon both the frictional and inherent strengths, the phenomenon of internal friction can be identified with the frictional part. The curvature of the Mohr failure envelope is interpreted as a consequence of differences in damage (cracking) accumulated in prefailure loading at different confining pressures.
As a comparison to airborne infrared (IR) flux measurements, ground-based sampling of fumarole and soil gases was used to characterize the quiescent degassing of CO2 from Oldoinyo Lengai volcano. Aerial and ground-based measurements are in good agreement: ∼75% of the aerially measured CO2 flux at Lengai (0.05–0.06 × 1012 mol yr−1 or 6000–7200 tonnes CO2 d−1) can be attributed to seven large crater vents. In contrast to Etna and Vulcano Island, where 15–50% of the total CO2 flux emanates diffusely through the volcanic flanks, diffuse emissions were measured only within 500 m of the crater rim at Lengai, contributing <2% of the total flux. The lack of extensive flank emissions may reflect the dimensions of the magma chamber and/or the lack of a shallow fluid flow system. Thermodynamic restoration of fumarole analyses shows that gases are the most CO2-rich and H2O-poor reported for any volcano, containing 64–74% CO2, 24–34% H2O, 0.88–1.0% H2, 0.1–0.4% CO and <0.1% H2S, HCl, HF, and CH4. Volatile emissions of S, Cl, and F at Oldoiyno Lengai are estimated as 4.5, 1.5, and 1.0 × 107 mol yr−1, respectively. Accuracy of the airborne technique was also assessed by measuring the C emission rate from a coal-burning power plant. CO2 fluxes were measured within ±10% near the plant; however, poor resolution at increased distances caused an underestimation of the flux by a factor of 2. The relatively large CO2 fluxes measured for alkaline volcanoes such as Oldoinyo Lengai or Etna may indicate that midplate volcanoes represent a large, yet relatively unknown, natural source of CO2.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.1029/96JB00173","issn":"01480227","usgsCitation":"Koepenick, K., Brantley, S., Thompson, J., Rowe, G., Nyblade, A., and Moshy, C., 1996, Volatile emissions from the crater and flank of Oldoinyo Lengai volcano, Tanzania: Journal of Geophysical Research B: Solid Earth, v. 101, no. 6, p. 13819-13830, https://doi.org/10.1029/96JB00173.","productDescription":"12 p.","startPage":"13819","endPage":"13830","costCenters":[{"id":615,"text":"Volcano Hazards Program","active":true,"usgs":true}],"links":[{"id":226897,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"101","issue":"6","noUsgsAuthors":false,"publicationDate":"1996-06-10","publicationStatus":"PW","scienceBaseUri":"505bc2bfe4b08c986b32ad33","contributors":{"authors":[{"text":"Koepenick, K.W.","contributorId":98052,"corporation":false,"usgs":true,"family":"Koepenick","given":"K.W.","email":"","affiliations":[],"preferred":false,"id":381188,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Brantley, S.L.","contributorId":71676,"corporation":false,"usgs":true,"family":"Brantley","given":"S.L.","email":"","affiliations":[],"preferred":false,"id":381184,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Thompson, J. M.","contributorId":77142,"corporation":false,"usgs":true,"family":"Thompson","given":"J. M.","affiliations":[],"preferred":false,"id":381186,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Rowe, G.L.","contributorId":23978,"corporation":false,"usgs":true,"family":"Rowe","given":"G.L.","affiliations":[],"preferred":false,"id":381183,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Nyblade, A.A.","contributorId":75703,"corporation":false,"usgs":true,"family":"Nyblade","given":"A.A.","email":"","affiliations":[],"preferred":false,"id":381185,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Moshy, C.","contributorId":92441,"corporation":false,"usgs":true,"family":"Moshy","given":"C.","email":"","affiliations":[],"preferred":false,"id":381187,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70019078,"text":"70019078 - 1996 - Determination of nitroaromatic explosives and their degradation products in unsaturated-zone water samples by high-performance liquid chromatography with photodiode-array, mass spectrometric, and tandem mass spectrometric detection","interactions":[],"lastModifiedDate":"2021-05-28T17:24:53.176314","indexId":"70019078","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3615,"text":"TrAC - Trends in Analytical Chemistry","active":true,"publicationSubtype":{"id":10}},"title":"Determination of nitroaromatic explosives and their degradation products in unsaturated-zone water samples by high-performance liquid chromatography with photodiode-array, mass spectrometric, and tandem mass spectrometric detection","docAbstract":"Mass spectrometry and tandem mass spectrometry, coupled by a thermospray interface to a high-performance liguid chromatography system and equipped with a photodiode array detector, were used to determine the presence of nitroaromatic explosives and their degradation products in USA unsaturated-zone water samples. Using this approach, the lower limits of quantitation for explosives determined by mass spectrometry in this study typically ranged from 10 to 100 ng/l.","language":"English","publisher":"Elsevier","doi":"10.1016/0165-9936(96)00050-7","usgsCitation":"Gates, P.M., Furlong, E., Dorsey, T., and Burkhardt, M., 1996, Determination of nitroaromatic explosives and their degradation products in unsaturated-zone water samples by high-performance liquid chromatography with photodiode-array, mass spectrometric, and tandem mass spectrometric detection: TrAC - Trends in Analytical Chemistry, v. 15, no. 8, p. 319-325, https://doi.org/10.1016/0165-9936(96)00050-7.","productDescription":"7 p.","startPage":"319","endPage":"325","numberOfPages":"7","costCenters":[{"id":452,"text":"National Water Quality Laboratory","active":true,"usgs":true}],"links":[{"id":226903,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"15","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ffb9e4b0c8380cd4f369","contributors":{"authors":[{"text":"Gates, Paul M.","contributorId":31411,"corporation":false,"usgs":true,"family":"Gates","given":"Paul","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":381610,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Furlong, E. T. 0000-0002-7305-4603","orcid":"https://orcid.org/0000-0002-7305-4603","contributorId":98346,"corporation":false,"usgs":true,"family":"Furlong","given":"E. T.","affiliations":[],"preferred":false,"id":381613,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dorsey, T.F.","contributorId":34278,"corporation":false,"usgs":true,"family":"Dorsey","given":"T.F.","email":"","affiliations":[],"preferred":false,"id":381611,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Burkhardt, M.R.","contributorId":70410,"corporation":false,"usgs":true,"family":"Burkhardt","given":"M.R.","email":"","affiliations":[],"preferred":false,"id":381612,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70018531,"text":"70018531 - 1996 - Occurrence and accumulation of pesticides and organic contaminants in river sediment, water and clam tissues from the San Joaquin River and tributaries, California","interactions":[],"lastModifiedDate":"2021-03-31T14:11:00.224733","indexId":"70018531","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Occurrence and accumulation of pesticides and organic contaminants in river sediment, water and clam tissues from the San Joaquin River and tributaries, California","docAbstract":"A study was conducted in 1992 to assess the effects of anthropogenic activities and land use on the water quality of the San Joaquin River and its major tributaries. This study focused on pesticides and organic contaminants, looking at distributions of contaminants in water, bed and suspended sediment, and the bivalve Corbicula fluminea. Results indicated that this river system is affected by agricultural practices and urban runoff. Sediments from Dry Creek contained elevated concentrations of polycyclic aromatic hydrocarbons (PAHs), possibly derived from urban runoff from the city of Modesto; suspended sediments contained elevated amounts of chlordane. Trace levels of triazine herbicides atrazine and simazine were present in water at most sites. Sediments, water, and bivalves from Orestimba Creek, a westside tributary draining agricultural areas, contained the greatest levels of DDT (1,1,1-trichloro-2-2-bis[p-chlorophenyl]ethane), and its degradates DDD (1,1-dichloro-2,2-bis[p-chlorophenyl]ethane), and DDE (1,1-dichloro-2,2- bis[p-chlorophenyl]ethylene). Sediment adsorption co efficients (K(oc)), and bioconcentration factors (BCF) in Corbicula of DDT, DDD, and DDE at Orestimba Creek were greater than predicted values. Streams of the western San Joaquin Valley can potentially transport significant amounts of chlorinated pesticides to the San Joaquin River, the delta, and San Francisco Bay. Organochlorine compounds accumulate in bivalves and sediment and may pose a problem to other biotic species in this watershed.
","language":"English","publisher":"Wiley","doi":"10.1897/1551-5028(1996)015<0172:OAAOPA>2.3.CO;2","usgsCitation":"Pereira, W.E., Domagalski, J.L., Hostettler, F., Brown, L., and Rapp, J.B., 1996, Occurrence and accumulation of pesticides and organic contaminants in river sediment, water and clam tissues from the San Joaquin River and tributaries, California: Environmental Toxicology and Chemistry, v. 15, no. 2, p. 172-180, https://doi.org/10.1897/1551-5028(1996)015<0172:OAAOPA>2.3.CO;2.","productDescription":"9 p.","startPage":"172","endPage":"180","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":226992,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"San Joaquin River and tributaries","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -119.06982421874999,\n 36.87962060502676\n ],\n [\n -120.728759765625,\n 38.66835610151506\n ],\n [\n -121.17919921875001,\n 39.58875727696545\n ],\n [\n -121.728515625,\n 39.9434364619742\n ],\n [\n -122.728271484375,\n 39.53793974517628\n ],\n [\n -122.178955078125,\n 38.315801006824984\n ],\n [\n -122.135009765625,\n 38.06539235133249\n ],\n [\n -120.377197265625,\n 36.89719446989036\n ],\n [\n -119.06982421874999,\n 36.87962060502676\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"15","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6b27e4b0c8380cd74547","contributors":{"authors":[{"text":"Pereira, W. E.","contributorId":46981,"corporation":false,"usgs":true,"family":"Pereira","given":"W.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":379954,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Domagalski, Joseph L. 0000-0002-6032-757X joed@usgs.gov","orcid":"https://orcid.org/0000-0002-6032-757X","contributorId":1330,"corporation":false,"usgs":true,"family":"Domagalski","given":"Joseph","email":"joed@usgs.gov","middleInitial":"L.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":379953,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hostettler, F. D.","contributorId":99563,"corporation":false,"usgs":true,"family":"Hostettler","given":"F. D.","affiliations":[],"preferred":false,"id":379956,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Brown, L. R. 0000-0001-6702-4531","orcid":"https://orcid.org/0000-0001-6702-4531","contributorId":66391,"corporation":false,"usgs":true,"family":"Brown","given":"L. R.","affiliations":[],"preferred":false,"id":379955,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Rapp, J. B.","contributorId":28987,"corporation":false,"usgs":true,"family":"Rapp","given":"J.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":379952,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70018155,"text":"70018155 - 1996 - Shallow ground-water quality beneath a major urban center: Denver, Colorado, USA","interactions":[],"lastModifiedDate":"2017-04-14T09:14:43","indexId":"70018155","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Shallow ground-water quality beneath a major urban center: Denver, Colorado, USA","docAbstract":"A survey of the chemical quality of ground water in the unconsolidated alluvial aquifer beneath a major urban center (Denver, Colorado, USA) was performed in 1993 with the objective of characterizing the quality of shallow ground-water in the urban area and relating water quality to land use. Thirty randomly selected alluvial wells were each sampled once for a broad range of dissolved constituents. The urban land use at each well site was sub- classified into one of three land-use settings: residential, commercial, and industrial. Shallow ground-water quality was highly variable in the urban area and the variability could be related to these land-use setting classifications. Sulfate (SO4) was the predominant anion in most samples from the residential and commercial land-use settings, whereas bicarbonate (HCO3) was the predominant anion in samples from the industrial land-use setting, indicating a possible shift in redox conditions associated with land use. Only three of 30 samples had nitrate concentrations that exceeded the US national drinking-water standard of 10 mg l-1 as nitrogen, indicating that nitrate contamination of shallow ground water may not be a serious problem in this urban area. However, the highest median nitrate concentration (4.2 mg l-1) was in samples from the residential setting, where fertilizer application is assumed to be most intense. Twenty-seven of 30 samples had detectable pesticides and nine of 82 analyzed pesticide compounds were detected at low concentrations, indicating that pesticides are widely distributed in shallow ground water in this urban area. Although the highest median total pesticide concentration (0.17 ??g l-1) was in the commercial setting, the herbicides prometon and atrazine were found in each land-use setting. Similarly, 25 of 29 samples analyzed had detectable volatile organic compounds (VOCs) indicating these compounds are also widely distributed in this urban area. The total VOC concentrations in sampled wells ranged from nondetectable to 23 442 ??g l-1. Widespread detections and occasionally high concentrations point to VOCs as the major anthropogenic ground-water impact in this urban environment. Generally, the highest VOC concentrations occurred in samples from the industrial setting. The most frequently detected VOC was the gasoline additive methyl tertbutyl ether (MTBE, in 23 of 29 wells). Results from this study indicate that the quality of shallow ground water in major urban areas can be related to land-use settings. Moreover, some VOCs and pesticides may be widely distributed at low concentrations in shallow ground water throughout major urban areas. As a result, the differentiation between point and non-point sources for these compounds in urban areas may be difficult.","language":"English","publisher":"Elsevier","doi":"10.1016/S0022-1694(96)03031-4","issn":"00221694","usgsCitation":"Bruce, B.W., and McMahon, P., 1996, Shallow ground-water quality beneath a major urban center: Denver, Colorado, USA: Journal of Hydrology, v. 186, no. 1-4, p. 129-151, https://doi.org/10.1016/S0022-1694(96)03031-4.","productDescription":"23 p.","startPage":"129","endPage":"151","numberOfPages":"23","costCenters":[],"links":[{"id":227323,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"186","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8e27e4b08c986b318771","contributors":{"authors":[{"text":"Bruce, B. W.","contributorId":19577,"corporation":false,"usgs":true,"family":"Bruce","given":"B.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":378707,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McMahon, P.B. 0000-0001-7452-2379","orcid":"https://orcid.org/0000-0001-7452-2379","contributorId":10762,"corporation":false,"usgs":true,"family":"McMahon","given":"P.B.","affiliations":[],"preferred":false,"id":378706,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":1012938,"text":"1012938 - 1996 - Alternative models of climatic effects on sockeye salmon, Oncorhynchus nerka, productivity in Bristol Bay, Alaska, and the Fraser River, British Columbia","interactions":[],"lastModifiedDate":"2023-10-30T16:07:15.947962","indexId":"1012938","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1660,"text":"Fisheries Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"Alternative models of climatic effects on sockeye salmon, Oncorhynchus nerka, productivity in Bristol Bay, Alaska, and the Fraser River, British Columbia","docAbstract":"We compare alternative models of sockeye salmon, Oncorhynchus nerka, productivity (returns per spawner) using more than 30 years of catch and escapement data for Bristol Bay, Alaska, and the Fraser River, British Columbia. The models examined include several alternative forms of models that incorporate climatic influences as well as models not based on climate. For most stocks, a stationary stock-recruitment relationship explains very little of the interannual variation in productivity. In Bristol Bay, productivity covaries among stocks and appears to be strongly related to fluctuations in climate. The best model for Bristol Bay sockeye involved a change in the 1970s in the parameters of the Ricker stock-recruitment curve; the stocks generally became more productive. In contrast, none of the models of Fraser River stocks that we examined explained much of the variability in their productivity.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1365-2419.1996.tb00113.x","usgsCitation":"Adkison, M., Peterman, R.M., Lapointe, M., Gillis, D., and Korman, J., 1996, Alternative models of climatic effects on sockeye salmon, Oncorhynchus nerka, productivity in Bristol Bay, Alaska, and the Fraser River, British Columbia: Fisheries Oceanography, v. 5, no. 3/4, p. 137-152, https://doi.org/10.1111/j.1365-2419.1996.tb00113.x.","productDescription":"16 p.","startPage":"137","endPage":"152","numberOfPages":"16","costCenters":[{"id":106,"text":"Alaska Biological Science Center","active":false,"usgs":true}],"links":[{"id":128559,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Canada, United States","state":"Alaska, British Columbia","otherGeospatial":"Bristol Bay, Fraser River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -163.08917539537347,\n 55.15894913740004\n ],\n [\n -159.65903895213302,\n 56.408726159786596\n ],\n [\n -158.17602722665475,\n 57.19195944055994\n ],\n [\n -157.29830935612335,\n 58.461147445772866\n ],\n [\n -156.79322102173407,\n 58.98280117370635\n ],\n [\n -157.9752794853864,\n 58.67730764289078\n ],\n [\n -158.49435227082103,\n 59.03661320736964\n ],\n [\n -158.9397596571492,\n 58.78915096520106\n ],\n [\n -158.89146570029132,\n 58.45509417523837\n ],\n [\n -159.69378831026978,\n 58.95507370498541\n ],\n [\n -159.850653950805,\n 58.80741292095564\n ],\n [\n -160.26784459821604,\n 59.08231392297492\n ],\n [\n -161.40189839361852,\n 58.72873938867144\n ],\n [\n -161.8147953272906,\n 58.612906621674114\n ],\n [\n -163.08917539537347,\n 55.15894913740004\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n },\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -122.7945920621268,\n 49.010316102691206\n ],\n [\n -121.63777796020763,\n 49.12024062648641\n ],\n [\n -121.27485556025441,\n 50.671610154564746\n ],\n [\n -118.41467539731029,\n 52.3631466622673\n ],\n [\n -120.2757998657401,\n 53.76177210227928\n ],\n [\n -124.82180432645121,\n 57.37084369674125\n ],\n [\n -126.55279133598167,\n 54.95493524366967\n ],\n [\n -125.28609801102313,\n 52.79760540626222\n ],\n [\n -122.7945920621268,\n 49.010316102691206\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"5","issue":"3/4","noUsgsAuthors":false,"publicationDate":"2007-10-05","publicationStatus":"PW","scienceBaseUri":"4f4e4adee4b07f02db687440","contributors":{"authors":[{"text":"Adkison, M.","contributorId":77086,"corporation":false,"usgs":true,"family":"Adkison","given":"M.","email":"","affiliations":[],"preferred":false,"id":318445,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Peterman, R. M.","contributorId":83871,"corporation":false,"usgs":false,"family":"Peterman","given":"R.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":318446,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lapointe, M.","contributorId":95006,"corporation":false,"usgs":false,"family":"Lapointe","given":"M.","email":"","affiliations":[],"preferred":false,"id":318447,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Gillis, D.","contributorId":37682,"corporation":false,"usgs":false,"family":"Gillis","given":"D.","email":"","affiliations":[],"preferred":false,"id":318444,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Korman, J.","contributorId":99925,"corporation":false,"usgs":true,"family":"Korman","given":"J.","affiliations":[],"preferred":false,"id":318448,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70018451,"text":"70018451 - 1996 - Origin and depositional environment of clastic deposits in the Hilo drill hole, Hawaii","interactions":[],"lastModifiedDate":"2019-03-15T10:42:16","indexId":"70018451","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Origin and depositional environment of clastic deposits in the Hilo drill hole, Hawaii","docAbstract":"Volcaniclastic units cored at depths of about 87, 164, 178, 226, and 246 m below sea level and carbonate units located between depths of 27 and 53 m below sea level in the Hilo drill core were found to be deposited at or near sea level. Four of these units are hydroclastic deposits, formed when subaerially erupted Mauna Loa lava flows entered the ocean and fragmented to produce quenched, glassy fragments during hydrovolcanic explosions. Ash units 24 and 26, at 178 m depth, accumulated at sea level in a freshwater bog. They contain pyroxenes crystallized from tholeiitic magma that we infer erupted explosively at the summit of Kilauea volcano. Two carbon‐rich layers from these ashes have a weighted average radiocarbon age of 38.6 ± 0.9 ka; the ashes probably correlate with the oldest and thickest part of the Pahala ash. Ash unit 44, at the transition from Mauna Kea to Mauna Loa lava flows, was probably nearly 3.2 m thick and is inferred to be equivalent to the lower thick part of the composite Homelani ash mapped in Hilo and on the flanks of Mauna Kea. The age of this part of Homelani ash is between 128 ± 33 and 200 ± 10 ka; it may have erupted subglacially during the Pohakuloa glacial maxima on Mauna Kea. Beach sand units 12 and 22 were derived from nearby Mauna Loa and Mauna Kea lava flows. The middle of beach sand unit 38 was derived mainly from lava erupted near the distal end of the subaerial east rift zone of Kilauea volcano; these sands were transported about 33 km northwest to Hilo Bay by prevailing longshore currents. Combined age, depth, and sea level markers in the core allow us to determine that lava flow recurrence intervals averaged one flow every 4 kyr during the past 86 kyr and one flow every 16 kyr between 86 and 200 ka at the drill site and that major explosive eruptions that deposit thick ash in Hilo have occurred only twice in the last 400 kyr. These recurrence intervals support the moderate lava flow hazard zonation (zone 3) for coastal Hilo previously determined from surficial mapping.
","language":"English","publisher":"AGU","doi":"10.1029/95JB03703","issn":"01480227","usgsCitation":"Beeson, M., Clague, D., and Lockwood, J.P., 1996, Origin and depositional environment of clastic deposits in the Hilo drill hole, Hawaii: Journal of Geophysical Research B: Solid Earth, v. 101, no. 5, p. 11617-11629, https://doi.org/10.1029/95JB03703.","productDescription":"13 p.","startPage":"11617","endPage":"11629","costCenters":[{"id":615,"text":"Volcano Hazards Program","active":true,"usgs":true}],"links":[{"id":227647,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"101","issue":"5","noUsgsAuthors":false,"publicationDate":"1996-05-10","publicationStatus":"PW","scienceBaseUri":"505a709de4b0c8380cd76125","contributors":{"authors":[{"text":"Beeson, M.H.","contributorId":83118,"corporation":false,"usgs":true,"family":"Beeson","given":"M.H.","email":"","affiliations":[],"preferred":false,"id":379621,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Clague, D.A.","contributorId":36129,"corporation":false,"usgs":true,"family":"Clague","given":"D.A.","email":"","affiliations":[],"preferred":false,"id":379620,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lockwood, J. P.","contributorId":104473,"corporation":false,"usgs":true,"family":"Lockwood","given":"J.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":379622,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ]}