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.
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":70018538,"text":"70018538 - 1996 - Reactive solute transport in acidic streams","interactions":[],"lastModifiedDate":"2019-02-20T09:09:10","indexId":"70018538","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3728,"text":"Water, Air, & Soil Pollution","onlineIssn":"1573-2932","printIssn":"0049-6979","active":true,"publicationSubtype":{"id":10}},"title":"Reactive solute transport in acidic streams","docAbstract":"Spatial and temporal profiles of Ph and concentrations of toxic metals in streams affected by acid mine drainage are the result of the interplay of physical and biogeochemical processes. This paper describes a reactive solute transport model that provides a physically and thermodynamically quantitative interpretation of these profiles. The model combines a transport module that includes advection-dispersion and transient storage with a geochemical speciation module based on MINTEQA2. Input to the model includes stream hydrologic properties derived from tracer-dilution experiments, headwater and lateral inflow concentrations analyzed in field samples, and a thermodynamic database. Simulations reproduced the general features of steady-state patterns of observed pH and concentrations of aluminum and sulfate in St. Kevin Gulch, an acid mine drainage stream near Leadville, Colorado. These patterns were altered temporarily by injection of sodium carbonate into the stream. A transient simulation reproduced the observed effects of the base injection.","language":"English","publisher":"Kluwer Academic Publishers","doi":"10.1007/BF00619281","issn":"00496979","usgsCitation":"Broshears, R.E., 1996, Reactive solute transport in acidic streams: Water, Air, & Soil Pollution, v. 90, no. 1-2, p. 195-204, https://doi.org/10.1007/BF00619281.","productDescription":"10 p.","startPage":"195","endPage":"204","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":227076,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205843,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00619281"}],"volume":"90","issue":"1-2","noUsgsAuthors":false,"publicationDate":"1996-07-01","publicationStatus":"PW","scienceBaseUri":"505a9585e4b0c8380cd81a81","contributors":{"authors":[{"text":"Broshears, R. E.","contributorId":75552,"corporation":false,"usgs":true,"family":"Broshears","given":"R.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":379973,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70018539,"text":"70018539 - 1996 - Climate change and northern prairie wetlands: Simulations of long-term dynamics","interactions":[],"lastModifiedDate":"2018-03-12T15:53:45","indexId":"70018539","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2620,"text":"Limnology and Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"Climate change and northern prairie wetlands: Simulations of long-term dynamics","docAbstract":"A mathematical model (WETSIM 2.0) was used to simulate wetland hydrology and vegetation dynamics over a 32-yr period (1961–1992) in a North Dakota prairie wetland. A hydrology component of the model calculated changes in water storage based on precipitation, evapotranspiration, snowpack, surface runoff, and subsurface inflow. A spatially explicit vegetation component in the model calculated changes in distribution of vegetative cover and open water, depending on water depth, seasonality, and existing type of vegetation.
The model reproduced four known dry periods and one extremely wet period during the three decades. One simulated dry period in the early 1980s did not actually occur. Simulated water levels compared favorably with continuous observed water levels outside the calibration period (1990–1992). Changes in vegetative cover were realistic except for years when simulated water levels were significantly different than actual levels. These generally positive results support the use of the model for exploring the effects of possible climate changes on wetland resources.
","language":"English","publisher":"ASLO","doi":"10.4319/lo.1996.41.5.0871","issn":"00243590","usgsCitation":"Poiani, K.A., Johnson, W.C., Swanson, G.A., and Winter, T.C., 1996, Climate change and northern prairie wetlands: Simulations of long-term dynamics: Limnology and Oceanography, v. 41, no. 5, p. 871-881, https://doi.org/10.4319/lo.1996.41.5.0871.","productDescription":"11 p.","startPage":"871","endPage":"881","numberOfPages":"11","costCenters":[{"id":478,"text":"North Dakota Water Science Center","active":true,"usgs":true},{"id":34685,"text":"Dakota Water Science Center","active":true,"usgs":true}],"links":[{"id":227077,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"41","issue":"5","noUsgsAuthors":false,"publicationDate":"2003-12-22","publicationStatus":"PW","scienceBaseUri":"5059f64ce4b0c8380cd4c68e","contributors":{"authors":[{"text":"Poiani, Karen A.","contributorId":86280,"corporation":false,"usgs":true,"family":"Poiani","given":"Karen","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":379976,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Johnson, W. Carter","contributorId":189219,"corporation":false,"usgs":false,"family":"Johnson","given":"W.","email":"","middleInitial":"Carter","affiliations":[],"preferred":false,"id":379977,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Swanson, George A.","contributorId":49654,"corporation":false,"usgs":true,"family":"Swanson","given":"George","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":379975,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Winter, Thomas C.","contributorId":84736,"corporation":false,"usgs":true,"family":"Winter","given":"Thomas","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":379974,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70018546,"text":"70018546 - 1996 - Cyclic stressing and seismicity at strongly coupled subduction zones","interactions":[],"lastModifiedDate":"2024-11-13T17:19:12.979693","indexId":"70018546","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":"Cyclic stressing and seismicity at strongly coupled subduction zones","docAbstract":"We use the finite element method to analyze stress variations in and near a strongly coupled subduction zone during an earthquake cycle. Deformation is assumed to be uniform along strike (plane strain on a cross section normal to the trench axis), and periodic earthquake slip is imposed consistent with the long-term rate of plate convergence and degree of coupling. Simulations of stress and displacement rate fields represent periodic fluctuations in time superimposed on an average field. The oceanic plate, descending slab, and continental lithosphere are assumed here to respond elastically to these fluctuations, and the remaining mantle under and between plates is assumed to respond as Maxwell viscoelastic. In the first part of the analysis we find that computed stress fluctuations in space and time are generally consistent with observed earthquake mechanism variations with time since a great thrust event. In particular, trench-normal extensional earthquakes tend to occur early in the earthquake cycle toward the outer rise but occur more abundantly late in the cycle in the subducting slab downdip of the main thrust zone. Compressional earthquakes, when they occur at all, have the opposite pattern. Our results suggest also that the actual timing of extensional outer rise events is controlled by the rheology of the shallow aseismic portion of the thrust interface. The second part of the analysis shows the effects of mantle relaxation on the rate of ground surface deformation during the earthquake cycle. Models without relaxation predict a strong overall compressional strain rate in the continental plate above the main thrust zone, with the strain rate constant between mainshocks. However with significant relaxation present, a localized region of unusually low compressional, or even slightly extensional, strain rate develops along the surface of the continental plate above and somewhat inland from the downdip edge of the locked main thrust zone. The low strain rate starts in the middle or late part of the cycle, depending on position. This result suggests that the negligible or small contraction measured on the Shumagin Islands, Alaska, during 1980 to 1991, may not invalidate an interpretation of that region as being a moderately coupled subduction zone. In contrast, mantle relaxation causes only modest temporal nonuniformity of uplift rates in the overriding plate and of extensional stress rates in the subducting plate, even when the Maxwell time is an order of magnitude less than the recurrence interval.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/95JB03561","issn":"01480227","usgsCitation":"Taylor, M., Zheng, G., Rice, J., Stuart, W., and Dmowska, R., 1996, Cyclic stressing and seismicity at strongly coupled subduction zones: Journal of Geophysical Research B: Solid Earth, v. 101, no. 4, p. 8363-8381, https://doi.org/10.1029/95JB03561.","productDescription":"19 p.","startPage":"8363","endPage":"8381","numberOfPages":"19","costCenters":[],"links":[{"id":227212,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"101","issue":"4","noUsgsAuthors":false,"publicationDate":"1996-04-10","publicationStatus":"PW","scienceBaseUri":"5059fd25e4b0c8380cd4e669","contributors":{"authors":[{"text":"Taylor, M.A.J.","contributorId":14586,"corporation":false,"usgs":true,"family":"Taylor","given":"M.A.J.","email":"","affiliations":[],"preferred":false,"id":379996,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Zheng, G.","contributorId":20920,"corporation":false,"usgs":true,"family":"Zheng","given":"G.","email":"","affiliations":[],"preferred":false,"id":379998,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rice, J.R.","contributorId":14964,"corporation":false,"usgs":true,"family":"Rice","given":"J.R.","email":"","affiliations":[],"preferred":false,"id":379997,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Stuart, W.D.","contributorId":65865,"corporation":false,"usgs":true,"family":"Stuart","given":"W.D.","email":"","affiliations":[],"preferred":false,"id":380000,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Dmowska, R.","contributorId":37907,"corporation":false,"usgs":true,"family":"Dmowska","given":"R.","affiliations":[],"preferred":false,"id":379999,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70018548,"text":"70018548 - 1996 - Diagenesis, compaction, and fluid chemistry modeling of a sandstone near a pressure seal: Lower Tuscaloosa Formation, Gulf Coast","interactions":[],"lastModifiedDate":"2023-01-20T17:05:59.703758","indexId":"70018548","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":701,"text":"American Association of Petroleum Geologists Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Diagenesis, compaction, and fluid chemistry modeling of a sandstone near a pressure seal: Lower Tuscaloosa Formation, Gulf Coast","docAbstract":"Petrographic, isotopic, and fluid-inclusion evidence from normally and overpressured sand-stones of the lower Tuscaloosa Formation (Upper Cretaceous) in the Gulf Coast documents quartz-overgrowth precipitation at 90°C or less, calcite cement precipitation at approximately 100° and 135°C, and prismatic quartz cement precipitation at about 125°C. Textural evidence suggests that carbonate cement dissolution occurred before the second phases of calcite and quartz precipitation, and was followed by precipitation of grain-rimming chlorite and pore-filling kaolinite. Geochemical calculations demonstrate that present-day lower Tuscaloosa Formation water from 5500 m depth could either dissolve or precipitate calcite cements in model simulations of upward water low. Calcite dissolution or precipitation depends on PCO2 variability with depth (i.e., whether there is one or two-phase flow) or on the rate of generation of CO2 with depth. Calculations suggest that 105-106 rock volumes of water are required to flow through the section to precipitate 1-10% calcite cement.
Compaction analysis suggests that late-stage compaction occurred in normally pressured sandstones after dissolution of carbonate cements, but was hindered in overpressured sandstones despite the presence of high porosity. These results document the inhibition of compaction by overpressured fluids and constrain the timing of pressure seal formation. Modeling results demonstrate that the proposed paragenesis used to constrain timing of pressure seal formation is feasible, and that most of the cement diagenesis occurred before the pressure seal became effective as a permeability barrier.
","language":"English","publisher":"American Association of Petroleum Geologists","doi":"10.1306/64ED8C8C-1724-11D7-8645000102C1865D","usgsCitation":"Weedman, S., Brantley, S.L., Shiraki, R., and Poulson, S.R., 1996, Diagenesis, compaction, and fluid chemistry modeling of a sandstone near a pressure seal: Lower Tuscaloosa Formation, Gulf Coast: American Association of Petroleum Geologists Bulletin, v. 80, no. 7, p. 1045-1063, https://doi.org/10.1306/64ED8C8C-1724-11D7-8645000102C1865D.","productDescription":"19 p.","startPage":"1045","endPage":"1063","costCenters":[],"links":[{"id":227256,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Louisiana","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -92.16262732679756,\n 30.939723848711253\n ],\n [\n -92.16262732679756,\n 30.464362041821246\n ],\n [\n -90.94537494973406,\n 30.464362041821246\n ],\n [\n -90.94537494973406,\n 30.939723848711253\n ],\n [\n -92.16262732679756,\n 30.939723848711253\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"80","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0099e4b0c8380cd4f7f2","contributors":{"authors":[{"text":"Weedman, Suzanne","contributorId":87411,"corporation":false,"usgs":true,"family":"Weedman","given":"Suzanne","email":"","affiliations":[],"preferred":false,"id":380008,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Brantley, Susan L. 0000-0003-4320-2342","orcid":"https://orcid.org/0000-0003-4320-2342","contributorId":184201,"corporation":false,"usgs":false,"family":"Brantley","given":"Susan","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":380009,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Shiraki, R.","contributorId":107443,"corporation":false,"usgs":true,"family":"Shiraki","given":"R.","email":"","affiliations":[],"preferred":false,"id":380011,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Poulson, Simon R.","contributorId":187411,"corporation":false,"usgs":false,"family":"Poulson","given":"Simon","email":"","middleInitial":"R.","affiliations":[{"id":33648,"text":"Department of Geological Sciences and Engineering, University of Nevada","active":true,"usgs":false}],"preferred":false,"id":380010,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70018552,"text":"70018552 - 1996 - Grazing trails formed by soldier fly larvae (Diptera: Stratiomyidae) and their paleoenvironmental and paleoecological implications for the fossil record","interactions":[],"lastModifiedDate":"2018-03-06T15:43:32","indexId":"70018552","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1965,"text":"Ichnos: An International Journal for Plant and Animal Traces","onlineIssn":"1563-5236","printIssn":"1042-0940","active":true,"publicationSubtype":{"id":10}},"title":"Grazing trails formed by soldier fly larvae (Diptera: Stratiomyidae) and their paleoenvironmental and paleoecological implications for the fossil record","docAbstract":"Recent trails formed by soldier fly larvae (Díptera: Stratiomyidae) were examined in a shallow pond in the floodplain of a braided river in Jujuy Province, northwestern Argentina. Collected specimens were identified as Stratiomys convexa van der Wulp. Simple, irregularly meandering trails were produced across the surface of a muddy‐silty substrate. Since soldier fly larvae extend their caudal respiratory tube to the water‐air interface, they are restricted to extremely shallow water. The presence of benthic algal remains within the mouthparts of the larvae suggests a feeding habit of algal grazing. If preserved, these trails would be included in the ichno‐genus Helminthopsis, a common element in ancient freshwater ichno‐faunas. Helminthopsis preserved in pond and lacustrine margin deposits younger than Late Jurassic is regarded as one possible trace fossil analogue of the trails documented herein. Additionally, it is suggested that larvae of many aquatic Diptera with similar ecologic restrictions are potential tracemakers of Helminthopsis and other simple trails in these environments, particularly in post‐Paleozoic deposits. Studies of modern shallow aquatic habitats and reex‐amination of the ichnologic record stress the importance of fly larvae as tracemakers in lake margin and pond ecosystems. Ecologic requirements of soldier fly larvae make them inappropriate analogues of Helminthopsis tracemakers in deeper water, lacustrine settings.
","language":"English","publisher":"Taylor & Francis","doi":"10.1080/10420949609380124","usgsCitation":"Mángano, M., Buatois, L.A., and Claps, G.L., 1996, Grazing trails formed by soldier fly larvae (Diptera: Stratiomyidae) and their paleoenvironmental and paleoecological implications for the fossil record: Ichnos: An International Journal for Plant and Animal Traces, v. 4, no. 3, p. 163-167, https://doi.org/10.1080/10420949609380124.","productDescription":"5 p.","startPage":"163","endPage":"167","costCenters":[],"links":[{"id":227345,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"4","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2a50e4b0c8380cd5b087","contributors":{"authors":[{"text":"Mángano, M. Gabriela","contributorId":57619,"corporation":false,"usgs":false,"family":"Mángano","given":"M. Gabriela","affiliations":[{"id":35641,"text":"Kansas Geological Survey","active":true,"usgs":false}],"preferred":false,"id":380020,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Buatois, Luis A. 0000-0001-9523-750X","orcid":"https://orcid.org/0000-0001-9523-750X","contributorId":195823,"corporation":false,"usgs":false,"family":"Buatois","given":"Luis","email":"","middleInitial":"A.","affiliations":[{"id":35641,"text":"Kansas Geological Survey","active":true,"usgs":false}],"preferred":false,"id":380021,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Claps, Guillermo L.","contributorId":92444,"corporation":false,"usgs":false,"family":"Claps","given":"Guillermo","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":380022,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018559,"text":"70018559 - 1996 - Genetic characteristics of fluid inclusions in sphalerite from the Silesian-Cracow ores, Poland","interactions":[],"lastModifiedDate":"2012-03-12T17:19:24","indexId":"70018559","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3108,"text":"Prace - Panstwowego Instytutu Geologicznego","active":true,"publicationSubtype":{"id":10}},"title":"Genetic characteristics of fluid inclusions in sphalerite from the Silesian-Cracow ores, Poland","docAbstract":"Fluid inclusion studies in sphalerite from early-stage Zn-Pb mineralization in the Silesian-Cracow region (southern Poland), yielded homogenization temperatures (Th) from 80 to 158??C. Vertical thermal gradient of the parent fluids was 6 to 10??C, and the ore crystallization temperature ranges varied from <10??C at deep levels to 25??C at shallow levels. The peculiarities of formation of primary and secondary fluid inclusions from organic-matter-bearing water-dominated medium, position of the inclusions in crystals, features of secondary inclusions, the inclusion refilling phenomena, their formation on recrystallization of ores, and Th distribution in single fissure fillings were considered. The ore-forming fluids were liquid-hydrocarbon-bearing aqueous solutions of Na-Ca-Cl type with lower Ca contents in the south and higher Ca contents in the north of the region. The ore-forming fluids had salinities from nul to about 23 weight percent of NaCl equivalent. Three types of fluids were recognized, that mixed during ore precipitation: a) ascending fluids of low-to-moderate salinity and high, b) formation brines of high salinity and moderate Th, and c) descending waters of low salinity and low-to-moderate Th.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Prace - Panstwowego Instytutu Geologicznego","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"08669465","usgsCitation":"Kozlowski, A., Leach, D.L., and Viets, J., 1996, Genetic characteristics of fluid inclusions in sphalerite from the Silesian-Cracow ores, Poland: Prace - Panstwowego Instytutu Geologicznego, v. 154, p. 72-84.","startPage":"72","endPage":"84","numberOfPages":"13","costCenters":[],"links":[{"id":227431,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"154","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a1568e4b0c8380cd54dd0","contributors":{"authors":[{"text":"Kozlowski, A.","contributorId":49124,"corporation":false,"usgs":true,"family":"Kozlowski","given":"A.","email":"","affiliations":[],"preferred":false,"id":380038,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Leach, D. L.","contributorId":18758,"corporation":false,"usgs":true,"family":"Leach","given":"D.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":380037,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Viets, J.G.","contributorId":82300,"corporation":false,"usgs":true,"family":"Viets","given":"J.G.","affiliations":[],"preferred":false,"id":380039,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018561,"text":"70018561 - 1996 - Integrating a geographic information system, a scientific visualization system and an orographic precipitation model","interactions":[],"lastModifiedDate":"2012-03-12T17:19:25","indexId":"70018561","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1934,"text":"IAHS-AISH Publication","active":true,"publicationSubtype":{"id":10}},"title":"Integrating a geographic information system, a scientific visualization system and an orographic precipitation model","docAbstract":"Investigating natural, potential, and man-induced impacts on hydrological systems commonly requires complex modelling with overlapping data requirements, and massive amounts of one- to four-dimensional data at multiple scales and formats. Given the complexity of most hydrological studies, the requisite software infrastructure must incorporate many components including simulation modelling, spatial analysis and flexible, intuitive displays. There is a general requirement for a set of capabilities to support scientific analysis which, at this time, can only come from an integration of several software components. Integration of geographic information systems (GISs) and scientific visualization systems (SVSs) is a powerful technique for developing and analysing complex models. This paper describes the integration of an orographic precipitation model, a GIS and a SVS. The combination of these individual components provides a robust infrastructure which allows the scientist to work with the full dimensionality of the data and to examine the data in a more intuitive manner.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"IAHS-AISH Publication","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"01447815","usgsCitation":"Hay, L., and Knapp, L., 1996, Integrating a geographic information system, a scientific visualization system and an orographic precipitation model: IAHS-AISH Publication, no. 235, p. 123-131.","startPage":"123","endPage":"131","numberOfPages":"9","costCenters":[],"links":[{"id":227480,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"issue":"235","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3c74e4b0c8380cd62d50","contributors":{"authors":[{"text":"Hay, L.","contributorId":72103,"corporation":false,"usgs":true,"family":"Hay","given":"L.","email":"","affiliations":[],"preferred":false,"id":380046,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Knapp, L.","contributorId":83290,"corporation":false,"usgs":true,"family":"Knapp","given":"L.","email":"","affiliations":[],"preferred":false,"id":380047,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018564,"text":"70018564 - 1996 - A top specified boundary layer (TSBL) approximation approach for the simulation of groundwater contamination processes","interactions":[],"lastModifiedDate":"2012-03-12T17:19:24","indexId":"70018564","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2233,"text":"Journal of Contaminant Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"A top specified boundary layer (TSBL) approximation approach for the simulation of groundwater contamination processes","docAbstract":"This paper presents improvements in the 'classical boundary layer' (CBL) approximation method to obtain simple but robust initial characterization of aquifer contamination processes. Contaminants are considered to penetrate into the groundwater through the free surface of the aquifer. The improved method developed in this study is termed the 'top specified boundary layer' (TSBL) approach. It involves the specification of the contaminant concentration at the top of the contaminated 'region of interest' (ROI), which is simulated as a boundary layer. the TSBL modification significantly improves the ability of the boundary layer method to predict the development of concentration profiles over both space and time. The TSBL method can be useful for the simulation of cases in which the contaminant concentration is prescribed at the aquifer's free surface as well as for cases in which the contaminant mass flux is prescribed at the surface.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Contaminant Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/0169-7722(95)00083-6","issn":"01697722","usgsCitation":"Rubin, H., and Buddemeier, R., 1996, A top specified boundary layer (TSBL) approximation approach for the simulation of groundwater contamination processes: Journal of Contaminant Hydrology, v. 22, no. 1-2, p. 123-144, https://doi.org/10.1016/0169-7722(95)00083-6.","startPage":"123","endPage":"144","numberOfPages":"22","costCenters":[],"links":[{"id":205933,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0169-7722(95)00083-6"},{"id":227525,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"22","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e5ffe4b0c8380cd470bc","contributors":{"authors":[{"text":"Rubin, H.","contributorId":54358,"corporation":false,"usgs":true,"family":"Rubin","given":"H.","email":"","affiliations":[],"preferred":false,"id":380052,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Buddemeier, R. W.","contributorId":86492,"corporation":false,"usgs":true,"family":"Buddemeier","given":"R. W.","affiliations":[],"preferred":false,"id":380053,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018566,"text":"70018566 - 1996 - Modeling reservoir density underflow and interflow from a chemical spill","interactions":[],"lastModifiedDate":"2018-03-08T15:20:52","indexId":"70018566","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Modeling reservoir density underflow and interflow from a chemical spill","docAbstract":"An integral simulation model has been developed for understanding and simulating the process of a density current and the transport of spilled chemicals in a stratified reservoir. The model is capable of describing flow behavior and mixing mechanisms in different flow regimes (plunging flow, underflow, and interflow). It computes flow rate, velocity, flow thickness, mixing parameterized by entrainment and dilution, depths of plunging, separation and intrusion, and time of travel. The model was applied to the Shasta Reservoir in northern California during the July 1991 Sacramento River chemical spill. The simulations were used to assist in the emergency response, confirm remediation measures, and guide data collection. Spill data that were available after the emergency response are used to conduct a postaudit of the model results. Predicted flow parameters are presented and compared with observed interflow intrusion depth, travel time, and measured concentrations of spilled chemicals. In the reservoir, temperature difference between incoming river flow and ambient lake water played a dominant role during the processes of flow plunging, separation, and intrusion. With the integral approach, the gross flow behavior can be adequately described and information useful in the analysis of contaminated flow in a reservoir after a spill is provided.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/95WR03486","usgsCitation":"Gu, R., McCutcheon, S.C., and Wang, P., 1996, Modeling reservoir density underflow and interflow from a chemical spill: Water Resources Research, v. 32, no. 3, p. 695-705, https://doi.org/10.1029/95WR03486.","productDescription":"11 p.","startPage":"695","endPage":"705","costCenters":[],"links":[{"id":227569,"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":"505a5c23e4b0c8380cd6fa7f","contributors":{"authors":[{"text":"Gu, Ruochuan","contributorId":152295,"corporation":false,"usgs":false,"family":"Gu","given":"Ruochuan","email":"","affiliations":[],"preferred":false,"id":380059,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McCutcheon, Steve C.","contributorId":84374,"corporation":false,"usgs":true,"family":"McCutcheon","given":"Steve","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":380060,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Wang, Pei-Fang","contributorId":176998,"corporation":false,"usgs":false,"family":"Wang","given":"Pei-Fang","email":"","affiliations":[],"preferred":false,"id":380058,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018569,"text":"70018569 - 1996 - Late Quaternary variations in relative sea level due to glacial cycle polar wander","interactions":[],"lastModifiedDate":"2024-02-12T12:06:01.178724","indexId":"70018569","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":"Late Quaternary variations in relative sea level due to glacial cycle polar wander","docAbstract":"Growth and decay of continental ice sheets can excite significant motion of the Earth's rotation pole and cause a complex spatio-temporal pattern of changes in relative sea level. These two effects have generally been considered separately, but may interact in important ways. In particular, a simple model of the melting of the Laurentide ice sheet causes a uniform eustatic sea level rise of 55 m, and also induces a motion of the rotation pole by 0.1 to 1 degree, depending on viscosity structure in the mantle. This motion produces a secular pole tide, which is a spherical harmonic degree 2, order 1 component of the relative sea level pattern, with peak-to-peak amplitude of 20 to 40 m. The maximum effect is along the great circle passing through the path of the pole and at latitudes of ±45°. This secular pole tide has been ignored in most previous attempts to estimate ice sheet loading history and mantle viscosity from global patterns of relative sea level change. It has a large influence along the East coast of North America and the West coast of South America, and significantly contributes to present day rates of relative sea level change.
The transport potential of the herbicide atrazine (2-chloro-4-ethyl-6-isopropyl-s-triazine) through a 1-meter-thick root zone of corn (Zea mays L.) in a silty-loam soil in Kansas was estimated for a 22-year period (1972-93) using the one-dimensional water-flow and solute-transport model LEACHM. Results demonstrate that, for this soil, atrazine transport is directly related to the amount and timing of rain that follows spring applications of atrazine. Two other critical transport factors were important in wet years — [1] variability in atrazine application rate, and [2] atrazine degradation rates below the root zone. Results demonstrate that the coincidence of heavy rain soon after atrazine application can cause herbicide to move below the rooting zone into depths at which biodegradation rates are assumed to be low but are often unknown. Atrazine that reaches below the rooting zone and persists in the underlying soil can subsequently be transported into ground water as soil water drains, typically after the growing season. A frequency analysis of atrazine concentrations in subsurface drainage, combined with field data, demonstrates the relative importance of critical transport factors and confirms a need for definitive estimates of atrazine-degradation rates below the root zone. The analysis indicates that periodic leaching of atrazine can be expected for this soil when rainfall that exceeds 20 cm/mo coincides with atrazine presence in soil.
","language":"English","publisher":"ACS Publications","doi":"10.1021/bk-1996-0630.ch009","usgsCitation":"Eckhardt, D.A., and Wagenet, R.J., 1996, Estimation of the potential for atrazine transport in a silt loam soil: ACS Symposium Series, v. 630, p. 101-116, https://doi.org/10.1021/bk-1996-0630.ch009.","productDescription":"16 p.","startPage":"101","endPage":"116","numberOfPages":"16","costCenters":[],"links":[{"id":226996,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"630","noUsgsAuthors":false,"publicationDate":"2009-07-23","publicationStatus":"PW","scienceBaseUri":"505a0bb5e4b0c8380cd52837","contributors":{"authors":[{"text":"Eckhardt, D. A. V.","contributorId":31127,"corporation":false,"usgs":true,"family":"Eckhardt","given":"D.","email":"","middleInitial":"A. V.","affiliations":[],"preferred":false,"id":380090,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wagenet, R. J.","contributorId":55584,"corporation":false,"usgs":true,"family":"Wagenet","given":"R.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":380091,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018582,"text":"70018582 - 1996 - Reactive transport modeling of acidic metal-contaminated ground water at a site with sparse spatial information","interactions":[],"lastModifiedDate":"2018-09-19T10:59:38","indexId":"70018582","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3280,"text":"Reviews in Mineralogy","active":true,"publicationSubtype":{"id":10}},"title":"Reactive transport modeling of acidic metal-contaminated ground water at a site with sparse spatial information","docAbstract":"No abstract available.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Reviews in Mineralogy","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"02750279","usgsCitation":"Glynn, P., and Brown, J., 1996, Reactive transport modeling of acidic metal-contaminated ground water at a site with sparse spatial information: Reviews in Mineralogy, v. 34, p. 377-438.","productDescription":"62 p.","startPage":"377","endPage":"438","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":227126,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"34","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a958ae4b0c8380cd81aa2","contributors":{"authors":[{"text":"Glynn, P.","contributorId":56394,"corporation":false,"usgs":true,"family":"Glynn","given":"P.","affiliations":[],"preferred":false,"id":380109,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Brown, J.","contributorId":57801,"corporation":false,"usgs":true,"family":"Brown","given":"J.","affiliations":[],"preferred":false,"id":380110,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018583,"text":"70018583 - 1996 - Scientific objectives of human exploration of Mars","interactions":[],"lastModifiedDate":"2012-03-12T17:19:26","indexId":"70018583","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":706,"text":"American Astronautical Society, Scientific Technology Series","active":true,"publicationSubtype":{"id":10}},"title":"Scientific objectives of human exploration of Mars","docAbstract":"While human exploration of Mars is unlikely to be undertaken for science reasons alone, science will be the main beneficiary. A wide range of science problems can be addressed at Mars. The planet formed in a different part of the solar system from the Earth and retains clues concerning compositional and environmental conditions in that part of the solar system when the planets formed. Mars has had a long and complex history that has involved almost as wide a range of processes as occurred on Earth. Elucidation of this history will require a comprehensive program of field mapping, geophysical sounding, in situ analyses, and return of samples to Earth that are representative of the planet's diversity. The origin and evolution of the Mars' atmosphere are very different from the Earth's, Mars having experienced major secular and cyclical changes in climate. Clues as to precisely how the atmosphere has evolved are embedded in its present chemistry, possibly in surface sinks of former atmosphere-forming volatiles, and in the various products of interaction between the atmosphere and surface. The present atmosphere also provides a means of testing general circulation models applicable to all planets. Although life is unlikely to be still extant on Mars, life may have started early in the planet's history. A major goal of any future exploration will, therefore, be to search for evidence of indigenous life.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"American Astronautical Society, Scientific Technology Series","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"02784017","usgsCitation":"Carr, M.H., 1996, Scientific objectives of human exploration of Mars: American Astronautical Society, Scientific Technology Series, v. 86, p. 515-535.","startPage":"515","endPage":"535","numberOfPages":"21","costCenters":[],"links":[{"id":227168,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8789e4b08c986b31652f","contributors":{"authors":[{"text":"Carr, M. H.","contributorId":84727,"corporation":false,"usgs":true,"family":"Carr","given":"M.","email":"","middleInitial":"H.","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":false,"id":380111,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70018589,"text":"70018589 - 1996 - A new high-precision borehole-temperature logging system used at GISP2, Greenland, and Taylor Dome, Antarctica","interactions":[],"lastModifiedDate":"2024-05-07T00:04:03.026088","indexId":"70018589","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2328,"text":"Journal of Glaciology","active":true,"publicationSubtype":{"id":10}},"title":"A new high-precision borehole-temperature logging system used at GISP2, Greenland, and Taylor Dome, Antarctica","docAbstract":"We describe a high-precision (0.1–1.0 mK) borehole-temperature (BT) logging system developed at the United States Geological Survey (USGS) for use in remote polar regions. We discuss calibration, operational and data-processing procedures, and present an analysis of the measurement errors. The system is modular to facilitate calibration procedures and field repairs. By interchanging logging cables and temperature sensors, measurements can be made in either shallow air-filled boreholes or liquid-filled holes up to 7 km deep. Data can be acquired in either incremental or continuous-logging modes. The precision of data collected by the new logging system is high enough to detect and quantify various thermal effects at the milli-Kelvin level. To illustrate this capability, we present sample data from the 3 km deep borehole at GISP2, Greenland, and from a 130 m deep air-filled hole at Taylor Dome, Antarctica. The precision of the processed GISP2 continuous temperature logs is 0.25–0.34 mK, while the accuracy is estimated to be 4.5 mK. The effects of fluid convection and the dissipation of the thermal disturbance caused by drilling the borehole are clearly visible in the data. The precision of the incremental Taylor Dome measurements varies from 0.11 to 0.32 mK. depending on the wind strength during the experiments. With this precision, we found that temperature fluctuations and multi-hour trends in the BT measurements correlate well with atmospheric-pressure changes.
The Santa Rosita Formation is one the most widely distributed lower Paleozoic units of northwest Argentina. At the Quebrada del Salto Alto section, east of Purmamarca, Jujuy Province, it is represented by four sedimentary facies: thick‐bedded planar cross‐stratified quartzose sandstones (A), thin‐bedded planar cross‐stratified quartzose sandstones and mudstones (B), wave‐rippled sandstones and bioturbated mudstones (C), and black and greenish gray shales (D). Paleocurrent data, sandstone architecture, and sedimentary structures from faciès A and B indicate bipolar/bimodal paleoflows, suggesting the action of tidal currents. The succession is interpreted as that of a tide‐dominated shelf, with only secondary influence of wave processes. Trace fossils are restricted to facies B and C.
The Cruziana ichnocoenosis is preserved on the soles of thin‐bedded planar cross‐stratified quartzose sandstones (faciès B). This ichnocoenosis consists of Conostichus isp., Cruziana omanica, C. semiplicata, C. cf. tortworthi, Cruziana isp. Helminthopsis abeli, Monomorphichnus bilinearis, M. multilineatus, Palaeophycus tubularis, Rusophycus carbonarias, R. latus, and R. isp. The occurrence of Cruziana semiplicata, C. omanica, C. cf. tortworthi, and Rusophycus latus supports a Late Cambrian‐Tremadoc age. Slabbing of Cruziana shows complex interactions between biologic and sedimentologic processes, and suggests a predominance of exhumed traces, washed out and recast by tractive sand deposition. Sandstone soles are densely packed with biogenic structures and exhibit distinctive clusters of Rusophycus isp. that most likely represent trilobite nesting burrows. The Cruziana ichnocoenosis records the resident fauna of a protected, lower intertidal to subtidal interbar setting.
The Skolithos ichnocoenosis is represented by high to low density vertical burrows of Skolithos linearis, which extend downwards to the quartzose sandstone soles of faciès B and cross the Cruziana ichnocoenosis. The Skolithos ichnocoenosis represents colonization by suspension‐feeding organisms following a major change in environmental conditions, related to the migration of lower intertidal to subtidal sandwaves.
The Planolites ichnocoenosis consists exclusively of Planolites montanus within mudstones overlying wave‐rippled sandstones (facies C). The Planolites ichnocoenosis records opportunistic colonization by inf aunal deposit feeders that mined the organic‐rich fine‐grained sediment during the waning phase of storms that scoured organic detritus from the sea bottom.
The section records, from base to top, a Cruziana‐Skolithos ichnofacies zone, a Skolithos ichnofacies zone and an unbioturbated zone typified by the thick‐bedded cross‐stratified quartzose sandstone (fades A). This trend reflects progressively higher energy conditions linked to the establishment of a large sand wave complex. The presence of a mixed Cruziana‐Skolithos ichnofacies in the lower interval reflects changes in substrate and energy levels, rather than water depth. Accordingly, contrasting ichnocoenoses from interbars (Cruziana) and sandwaves (Skolithos) must be considered an example of ichnofacies controlled by local parameters instead of general bathymétrie trends. Conversely, the vertical replacement of the Cruziana ichnofacies by the Skolithos ichnofacies towards the middle interval of the section reflects the environmental changes associated with the transition between the intertidal and subtidal zones. As overall tidal energy increases from supratidal to subtidal settings, the Skolithos ichnofacies tends to occur seaward of the Cruzianaichnofacies in tide‐dominated shallow marine environments. Therefore, onshore‐offshore ichnofacies replacement in tide‐dominated shallow seas is opposite to that in wave‐dominated marine settings.
","language":"English","publisher":"Taylor & Francis","doi":"10.1080/10420949609386406","usgsCitation":"Mángano, M., Buatois, L.A., and Acenolaza, G.F., 1996, Trace fossils and sedimentary facies from a Late Cambrian‐Early Ordovician tide‐dominated shelf (Santa Rosita Formation, northwest Argentina): Implications for ichnofacies models of shallow marine successions: Ichnos: An International Journal for Plant and Animal Traces, v. 5, no. 1, p. 53-88, https://doi.org/10.1080/10420949609386406.","productDescription":"36 p.","startPage":"53","endPage":"88","costCenters":[],"links":[{"id":227306,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Argentina","geographicExtents":"{\"type\":\"FeatureCollection\",\"features\":[{\"type\":\"Feature\",\"geometry\":{\"type\":\"MultiPolygon\",\"coordinates\":[[[[-65.5,-55.2],[-66.45,-55.25],[-66.95992,-54.89681],[-67.56244,-54.87001],[-68.63335,-54.8695],[-68.63401,-52.63637],[-68.25,-53.1],[-67.75,-53.85],[-66.45,-54.45],[-65.05,-54.7],[-65.5,-55.2]]],[[[-64.96489,-22.07586],[-64.37702,-22.79809],[-63.98684,-21.99364],[-62.84647,-22.03499],[-62.68506,-22.24903],[-60.84656,-23.88071],[-60.02897,-24.0328],[-58.80713,-24.77146],[-57.77722,-25.16234],[-57.63366,-25.60366],[-58.61817,-27.12372],[-57.60976,-27.3959],[-56.4867,-27.5485],[-55.69585,-27.38784],[-54.78879,-26.62179],[-54.62529,-25.73926],[-54.13005,-25.54764],[-53.62835,-26.12487],[-53.64874,-26.92347],[-54.49073,-27.47476],[-55.16229,-27.88192],[-56.2909,-28.85276],[-57.62513,-30.21629],[-57.87494,-31.01656],[-58.14244,-32.0445],[-58.13265,-33.04057],[-58.34961,-33.26319],[-58.42707,-33.90945],[-58.49544,-34.43149],[-57.22583,-35.28803],[-57.36236,-35.97739],[-56.73749,-36.41313],[-56.78829,-36.90157],[-57.74916,-38.18387],[-59.23186,-38.72022],[-61.23745,-38.92842],[-62.33596,-38.82771],[-62.12576,-39.4241],[-62.33053,-40.17259],[-62.14599,-40.6769],[-62.7458,-41.02876],[-63.77049,-41.16679],[-64.73209,-40.80268],[-65.11804,-41.06431],[-64.97856,-42.058],[-64.30341,-42.35902],[-63.75595,-42.04369],[-63.45806,-42.56314],[-64.3788,-42.87356],[-65.1818,-43.49538],[-65.32882,-44.50137],[-65.56527,-45.03679],[-66.50997,-45.03963],[-67.29379,-45.5519],[-67.58055,-46.30177],[-66.59707,-47.03392],[-65.64103,-47.23613],[-65.98509,-48.13329],[-67.16618,-48.69734],[-67.81609,-49.86967],[-68.72875,-50.26422],[-69.13854,-50.73251],[-68.81556,-51.7711],[-68.14999,-52.34998],[-68.57155,-52.29944],[-69.49836,-52.14276],[-71.9148,-52.00902],[-72.3294,-51.42596],[-72.30997,-50.67701],[-72.97575,-50.74145],[-73.32805,-50.37879],[-73.41544,-49.31844],[-72.64825,-48.87862],[-72.33116,-48.24424],[-72.44736,-47.73853],[-71.91726,-46.88484],[-71.55201,-45.56073],[-71.65932,-44.97369],[-71.22278,-44.78424],[-71.3298,-44.40752],[-71.79362,-44.20717],[-71.46406,-43.78761],[-71.91542,-43.40856],[-72.1489,-42.25489],[-71.7468,-42.05139],[-71.91573,-40.83234],[-71.68076,-39.80816],[-71.41352,-38.91602],[-70.81466,-38.553],[-71.11863,-37.57683],[-71.12188,-36.65812],[-70.36477,-36.00509],[-70.38805,-35.16969],[-69.81731,-34.19357],[-69.81478,-33.27389],[-70.0744,-33.09121],[-70.53507,-31.36501],[-69.91901,-30.33634],[-70.01355,-29.36792],[-69.65613,-28.45914],[-69.00123,-27.52121],[-68.29554,-26.89934],[-68.5948,-26.50691],[-68.386,-26.18502],[-68.41765,-24.51855],[-67.32844,-24.0253],[-66.98523,-22.98635],[-67.10667,-22.73592],[-66.27334,-21.83231],[-64.96489,-22.07586]]]]},\"properties\":{\"name\":\"Argentina\"}}]}","volume":"5","issue":"1","noUsgsAuthors":false,"publicationDate":"2008-12-17","publicationStatus":"PW","scienceBaseUri":"505bb665e4b08c986b326c3c","contributors":{"authors":[{"text":"Mángano, M. Gabriela","contributorId":57619,"corporation":false,"usgs":false,"family":"Mángano","given":"M. Gabriela","affiliations":[{"id":35641,"text":"Kansas Geological Survey","active":true,"usgs":false}],"preferred":false,"id":380163,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Buatois, Luis A. 0000-0001-9523-750X","orcid":"https://orcid.org/0000-0001-9523-750X","contributorId":195823,"corporation":false,"usgs":false,"family":"Buatois","given":"Luis","email":"","middleInitial":"A.","affiliations":[{"id":35641,"text":"Kansas Geological Survey","active":true,"usgs":false}],"preferred":false,"id":380165,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Acenolaza, Guillermo F.","contributorId":24936,"corporation":false,"usgs":false,"family":"Acenolaza","given":"Guillermo","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":380164,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018600,"text":"70018600 - 1996 - Experimental investigation and modeling of uranium (VI) transport under variable chemical conditions","interactions":[],"lastModifiedDate":"2019-02-20T08:50:46","indexId":"70018600","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Experimental investigation and modeling of uranium (VI) transport under variable chemical conditions","docAbstract":"The transport of adsorbing and complexing metal ions in porous media was investigated with a series of batch and column experiments and with reactive solute transport modeling. Pulses of solutions containing U(VI) were pumped through columns filled with quartz grains, and the breakthrough of U(VI) was studied as a function of variable solution composition (pH, total U(VI) concentration, total fluoride concentration, and pH-buffering capacity). Decreasing pH and the formation of nonadsorbing aqueous complexes with fluoride increased U(VI) mobility. A transport simulation with surface complexation model (SCM) parameters estimated from batch experiments was able to predict U(VI) retardation in the column experiments within 30%. SCM parameters were also estimated directly from transport data, using the results of three column experiments collected at different pH and U(VI) pulse concentrations. SCM formulations of varying complexity (multiple surface types and reaction stoichiometries) were tested to examine the trade-off between model simplicity and goodness of fit to breakthrough. A two-site model (weak- and strong-binding sites) with three surface complexation reactions fit these transport data well. With this reaction set the model was able to predict (1) the effects of fluoride complexation on U(VI) retardation at two different pH values and (2) the effects of temporal variability of pH on U(VI) transport caused by low pH buffering. The results illustrate the utility of the SCM approach in modeling the transport of adsorbing inorganic solutes under variable chemical conditions.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/95WR02815","usgsCitation":"Kohler, M., Curtis, G., Kent, D., and Davis, J., 1996, Experimental investigation and modeling of uranium (VI) transport under variable chemical conditions: Water Resources Research, v. 32, no. 12, p. 3539-3551, https://doi.org/10.1029/95WR02815.","productDescription":"13 p.","startPage":"3539","endPage":"3551","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":227432,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"32","issue":"12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0dd4e4b0c8380cd531f4","contributors":{"authors":[{"text":"Kohler, M.","contributorId":32694,"corporation":false,"usgs":true,"family":"Kohler","given":"M.","affiliations":[],"preferred":false,"id":380188,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Curtis, G.P.","contributorId":65619,"corporation":false,"usgs":true,"family":"Curtis","given":"G.P.","email":"","affiliations":[],"preferred":false,"id":380189,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kent, D.B.","contributorId":16588,"corporation":false,"usgs":true,"family":"Kent","given":"D.B.","email":"","affiliations":[],"preferred":false,"id":380187,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Davis, J.A.","contributorId":71694,"corporation":false,"usgs":true,"family":"Davis","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":380190,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70018603,"text":"70018603 - 1996 - Identification of groundwater parameters at Columbus, Mississippi, using a 3D inverse flow and transport model","interactions":[],"lastModifiedDate":"2012-03-12T17:19:25","indexId":"70018603","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1934,"text":"IAHS-AISH Publication","active":true,"publicationSubtype":{"id":10}},"title":"Identification of groundwater parameters at Columbus, Mississippi, using a 3D inverse flow and transport model","docAbstract":"An extensive amount of data including hydraulic heads, hydraulic conductivities and concentrations of several solutes from controlled injections have been collected during the MADE 1 and MADE 2 experiments at a heterogeneous site near Columbus, Mississippi. In this paper the use of three-dimensional inverse groundwater models including simultaneous estimation of flow and transport parameters is proposed to help identify the dominant characteristics at the site. Simulations show that using a hydraulic conductivity distribution obtained from 2187 borehole flowmeter tests directly in the model produces poor matches to the measured hydraulic heads and tritium concentrations. Alternatively, time averaged hydraulic head maps are used to define zones of constant hydraulic conductivity to be estimated. Preliminary simulations suggest that in the case of conservative transport many, but not all, of the major plume characteristics can be explained by large-scale heterogeneity in recharge and hydraulic conductivity.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"IAHS-AISH Publication","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"01447815","usgsCitation":"Barlebo, H., Rosbjerg, D., and Hill, M.C., 1996, Identification of groundwater parameters at Columbus, Mississippi, using a 3D inverse flow and transport model: IAHS-AISH Publication, v. 237, p. 189-208.","startPage":"189","endPage":"208","numberOfPages":"20","costCenters":[],"links":[{"id":227481,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"237","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3829e4b0c8380cd6147f","contributors":{"authors":[{"text":"Barlebo, H.C.","contributorId":90484,"corporation":false,"usgs":true,"family":"Barlebo","given":"H.C.","email":"","affiliations":[],"preferred":false,"id":380198,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rosbjerg, D.","contributorId":108266,"corporation":false,"usgs":true,"family":"Rosbjerg","given":"D.","affiliations":[],"preferred":false,"id":380199,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hill, M. C.","contributorId":48993,"corporation":false,"usgs":true,"family":"Hill","given":"M.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":380197,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018605,"text":"70018605 - 1996 - Kinetic and mineralogic controls on the evolution of groundwater chemistry and 87Sr/86Sr in a sandy silicate aquifer, northern Wisconsin, USA","interactions":[],"lastModifiedDate":"2019-02-20T10:20:07","indexId":"70018605","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Kinetic and mineralogic controls on the evolution of groundwater chemistry and 87Sr/86Sr in a sandy silicate aquifer, northern Wisconsin, USA","docAbstract":"Substantial flowpath-related variability of 87Sr/86Sr is observed in groundwaters collected from the Trout Lake watershed of northern Wisconsin. In the extensive shallow aquifer composed of sandy glacial outwash, groundwater is recharged either by seepage from lakes or by precipitation that infiltrates the inter-lake uplands. 87Sr/86Sr of groundwater derived mainly as seepage from a precipitation-dominated lake near the head of the watershed decreases with progressive water chemical evolution along its flowpath due primarily to enhanced dissolution of relatively unradiogenic plagioclase. In contrast, 87Sr/86Sr of groundwater derived mainly from precipitation that infiltrates upland areas is substantially greater than that of precipitation collected from the watershed, due to suppression of plagioclase dissolution together with preferential leaching of Sr from radiogenic phases such as K-feldspar and biotite. The results of a column experiment that simulated the effects of changing residence time of water in the aquifer sand indicate that mobile waters obtain relatively unradiogenic Sr, whereas stagnant waters obtain relatively radiogenic Sr. Nearly the entire range of strontium-isotope composition observed in groundwaters from the watershed was measured in the experimental product waters. The constant mobility of water along groundwater recharge flowpaths emanating from the lakes promotes the dissolution of relatively unradiogenic plagioclase, perhaps due to effective dispersal of clay mineral nuclei resulting from dissolution reactions. In contrast, episodic stagnation in the unsaturated zone along the upland recharge flowpaths suppresses plagioclase dissolution, perhaps due to accumulation of clay mineral nuclei on its reactive surfaces. Differences in redox conditions along these contrasting flowpaths probably enhance the observed differences in strontium isotope behavior. This study demonstrates that factors other than the calculated state of mineral saturation must be considered when attempting to simulate chemical evolution along flowpaths, and that reaction models must be able to incorporate changing contributions from reacting minerals in the calculations.","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(96)00052-X","issn":"00167037","usgsCitation":"Bullen, T., Krabbenhoft, D., and Kendall, C., 1996, Kinetic and mineralogic controls on the evolution of groundwater chemistry and 87Sr/86Sr in a sandy silicate aquifer, northern Wisconsin, USA: Geochimica et Cosmochimica Acta, v. 60, no. 10, p. 1807-1821, https://doi.org/10.1016/0016-7037(96)00052-X.","productDescription":"15 p.","startPage":"1807","endPage":"1821","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":227526,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205934,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0016-7037(96)00052-X"}],"volume":"60","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a40a3e4b0c8380cd64f0d","contributors":{"authors":[{"text":"Bullen, T.D.","contributorId":79911,"corporation":false,"usgs":true,"family":"Bullen","given":"T.D.","email":"","affiliations":[],"preferred":false,"id":380202,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Krabbenhoft, D. P. 0000-0003-1964-5020","orcid":"https://orcid.org/0000-0003-1964-5020","contributorId":90765,"corporation":false,"usgs":true,"family":"Krabbenhoft","given":"D. P.","affiliations":[],"preferred":false,"id":380203,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kendall, C. 0000-0002-0247-3405","orcid":"https://orcid.org/0000-0002-0247-3405","contributorId":35050,"corporation":false,"usgs":true,"family":"Kendall","given":"C.","affiliations":[],"preferred":false,"id":380201,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018607,"text":"70018607 - 1996 - The long-term salinity field in San Francisco Bay","interactions":[],"lastModifiedDate":"2019-02-20T09:36:12","indexId":"70018607","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1333,"text":"Continental Shelf Research","active":true,"publicationSubtype":{"id":10}},"title":"The long-term salinity field in San Francisco Bay","docAbstract":"Data are presented on long-term salinity behaviour in San Francisco Bay, California. A two-level, width averaged model of the tidally averaged salinity and circulation has been written in order to interpret the long-term (days to decades) salinity variability. The model has been used to simulate daily averaged salinity in the upper and lower levels of a 51 segment discretization of the Bay over the 22-yr period 1967-1988. Monthly averaged surface salinity from observations and monthly-averaged simulated salinity are in reasonable agreement. Good agreement is obtained from comparison with daily averaged salinity measured in the upper reaches of North Bay. The salinity variability is driven primarily by freshwater inflow with relatively minor oceanic influence. All stations exhibit a marked seasonal cycle in accordance with the Mediterranean climate, as well as a rich spectrum of variability due to extreme inflow events and extended periods of drought. Monthly averaged salinity intrusion positions have a pronounced seasonal variability and show an approximately linear response to the logarithm of monthly averaged Delta inflow. Although few observed data are available for studies of long-term salinity stratification, modelled stratification is found to be strongly dependent on freshwater inflow; the nature of that dependence varies throughout the Bay. Near the Golden Gate, stratification tends to increase up to very high inflows. In the central reaches of North Bay, modelled stratification maximizes as a function of inflow and further inflow reduces stratification. Near the head of North Bay, lowest summer inflows are associated with the greatest modelled stratification. Observations from the central reaches of North Bay show marked spring-neap variations in stratification and gravitational circulation, both being stronger at neap tides. This spring-neap variation is simulated by the model. A feature of the modelled stratification is a hysteresis in which, for a given spring-neap tidal range and fairly steady inflows, the stratification is higher progressing from neaps to springs than from springs to neaps. The simulated responses of the Bay to perturbations in coastal sea salinity and Delta inflow have been used to further delineate the time-scales of salinity variability. Simulations have been performed about low inflow, steady-state conditions for both salinity and Delta inflow perturbations. For salinity perturbations a small, sinusoidal salinity signal with a period of 1 yr has been applied at the coastal boundary as well as a pulse of salinity with a duration of one day. For Delta inflow perturbations a small, sinusoidally varying inflow signal with a period of 1 yr has been superimposed on an otherwise constant Delta inflow, as well as a pulse of inflow with a duration of one day. Perturbations is coastal salinity dissipate as they move through the Bay. Seasonal perturbations require about 40-45 days to propagate from the coastal ocean to the Delta and to the head of South Bay. The response times of the model to perturbations in freshwater inflow are faster than this in North Bay and comparable in South Bay. In North Bay, time-scales are consistent with advection due to lower level, up-estuary transport of coastal salinity perturbations; for inflow perturbations, faster response times arise from both upper level, down-estuary advection and much faster, down-estuary migration of isohalines in response to inflow volume continuity. In South Bay, the dominant time-scales are governed by tidal dispersion.
","language":"English","publisher":"Elsevier","doi":"10.1016/0278-4343(96)00032-5","issn":"02784343","usgsCitation":"Uncles, R., and Peterson, D.H., 1996, The long-term salinity field in San Francisco Bay: Continental Shelf Research, v. 16, no. 15, p. 2005-2039, https://doi.org/10.1016/0278-4343(96)00032-5.","productDescription":"35 p.","startPage":"2005","endPage":"2039","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"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":227571,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205950,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0278-4343(96)00032-5"}],"volume":"16","issue":"15","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bada5e4b08c986b323d44","contributors":{"authors":[{"text":"Uncles, R.J.","contributorId":33468,"corporation":false,"usgs":true,"family":"Uncles","given":"R.J.","affiliations":[],"preferred":false,"id":380208,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Peterson, D. H.","contributorId":92229,"corporation":false,"usgs":true,"family":"Peterson","given":"D.","middleInitial":"H.","affiliations":[],"preferred":false,"id":380209,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018608,"text":"70018608 - 1996 - A scan-angle correction for thermal infrared multispectral data using side lapping images","interactions":[],"lastModifiedDate":"2024-02-10T14:49:52.892313","indexId":"70018608","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":"A scan-angle correction for thermal infrared multispectral data using side lapping images","docAbstract":"Thermal infrared multispectral scanner (TIMS) images, acquired with side lapping flight lines, provide dual angle observations of the same area on the ground and can thus be used to estimate variations in the atmospheric transmission with scan angle. The method was tested using TIMS aircraft data for six flight lines with about 30% sidelap for an area within Joshua Tree National Park, California. Generally the results correspond to predictions for the transmission scan-angle coefficient based on a standard atmospheric model although some differences were observed at the longer wavelength channels. A change was detected for the last pair of lines that may indicate either spatial or temporal atmospheric variation. The results demonstrate that the method provides information for correcting regional survey data (requiring multiple adjacent flight lines) that can be important in detecting subtle changes in lithology.