Trenching-a widely used method for evaluating fault activity-has limitations that can mislead investigators. Some segments of fault strands in trench walls may not be visible, and this nonvisibility can lead to incorrect interpretations of time of most recent displacement and recurrence intervals on a fault.
We examined the logs of 163 trench exposures and tabulated data on more than 1,200 fault strands to investigate three categories of nonvisibility: (1) strands with obscure (invisible or poorly visible) segments, (2) strands that die out upward, and (3) strands that die out downward. About 14 percent of all the strands have obscure segments. Of the 143 strands on which it is possible to recognize dieout up (limited to strands for which position of ground surface at time of faulting is known), 45 percent do die out upward, and the fraction exceeds 70 percent for strike-slip and reverse faults. Thus a fault strand overlain by an apparently undisturbed deposit is not necessarily older than the deposit. More than 30 percent of all the strands die out downward, providing more evidence that fault strands can end for reasons other than being covered by deposits younger than the fault.
Analysis of trench-log data revealed various relations between geologic factors and nonvisibility of fault strands. For example, fault type affects the incidence of nonvisibility, which is generally most common on strike-slip faults, less common on reverse faults, and least common on normal fau Its. The type of material penetrated by the fault also influences nonvisibility, which tends to be more common in soil horizons and sand, and less common in gravel. Dieout down is weakly influenced by fault displacement, decreasing in frequency with increase in displacement; the frequencies of obscure segments and dieout up do not vary consistently with fault displacement. Frequency of obscure segments generally decreases with increase in length of obscure segments, and frequency of dieout up generally decreases with depth of dieout up. Length of obscure segments and depth of dieout up are typically less than the effective thickness of associated beds. On the basis of few data, obscure segments seem to be more common on faults with younger, rather than older, ages of latest displacement.
Our study revealed additional relations not directly related to nonvisibility. For example, the median widths of faults crossed by the trenches vary by fault type, strike-slip faults being narrower than dip-slip faults. In the shallow and mostly unconsolidated materials cut by the trenches, fault widths show only an erratic and, at best, weak relationship to fault displacements. Hanging walls are deformed more frequently than footwalls in dip-slip faults, but both walls are deformed at more than 30 percent of the exposures.
We tabulated several phenomena that may indicate faulting or provide evidence of prehistorical earthquakes. Rotation of pebbles was identified in 41 percent of the exposures having gravel in the fault zone; type of fault has no strong influence on the incidence of pebble rotation. Fissures were recorded at 52 percent of the exposures and were more common in strike-slip and normal faults than in reverse fau Its. Gouge was reported at 1 5 percent of the exposures; fault type has no significant influence on its frequency. Slickensides were noted at 10 percent of the exposures, and fault type has an unknown influence on their incidence. Slickensides in unconsolidated materials were restricted to clay, silt, and gouge. Other mechanical or hydrologic effects related to faulting or earthquakesrubble, breccia, mixing, crushing, polishing, water barriers, c;ind probable liquefaction effects-were reported at fewer than 1 0 percent of the exposures.
","language":"English","publisher":"U.S. Government Printing Office","publisherLocation":"Washington, D.C.","doi":"10.3133/b1947","usgsCitation":"Bonilla, M.G., and Lienkaemper, J.J., 1991, Factors affecting the recognition of faults exposed in exploratory trenches: U.S. Geological Survey Bulletin 1947, Report: v, 54 p.; Appendix: 71 p., https://doi.org/10.3133/b1947.","productDescription":"Report: v, 54 p.; Appendix: 71 p.","costCenters":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"links":[{"id":61708,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/bul/1947/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":342144,"rank":3,"type":{"id":3,"text":"Appendix"},"url":"https://pubs.usgs.gov/bul/1947/appendix.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":167172,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/bul/1947/report-thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a05e4b07f02db5f879e","contributors":{"authors":[{"text":"Bonilla, Manuel G.","contributorId":74384,"corporation":false,"usgs":true,"family":"Bonilla","given":"Manuel","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":211961,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lienkaemper, James J. 0000-0002-7578-7042 jlienk@usgs.gov","orcid":"https://orcid.org/0000-0002-7578-7042","contributorId":1941,"corporation":false,"usgs":true,"family":"Lienkaemper","given":"James","email":"jlienk@usgs.gov","middleInitial":"J.","affiliations":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"preferred":true,"id":211960,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":26899,"text":"wri914053 - 1991 - Ground-water levels, flow, and quality in northwestern Elkhart County, Indiana, 1980-89","interactions":[],"lastModifiedDate":"2024-01-11T22:00:08.313645","indexId":"wri914053","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"91-4053","title":"Ground-water levels, flow, and quality in northwestern Elkhart County, Indiana, 1980-89","docAbstract":"Ground-water data were collected in northwestern Elkhart County, Indiana, from 1980 through 1989 to monitor hydrologic conditions and to provide information necessary for waterresources managers to evaluate the ground-water resources in this area. The area of study includes a closed industrial landfill and several areas of industrial and municipal pumping. Water levels were measured twice a year in 68 wells, and water samples were collected once a year from 32 wells. The wells were screened in unconsolidated glacial-outwash deposits primarily sand and gravel.
\nDuring the study, measured ground-water levels ranged from about 6 feet above ground level to about 29 feet below ground level. The average depth to water for all wells was 10 feet, and the average water-level fluctuation for the entire study period was 4.8 feet. In the study area, ground water flows toward the St. Joseph River. Water levels near the river are higher than the stage of the river, indicating that ground water is discharged to the river.
\nWater samples were collected and analyzed to determine concentrations of dissolved bromide. Onsite measurements of specific conductance, pH, water temperature, and concentrations of dissolved oxygen and alkalinity were made at the time of sampling. The water samples had a median specific conductance of 516 microsiemens per centimeter at 25 degrees Celsius, a median ph of 7.6, a median alkalinity of 216 milligrams per liter (as calcium carbonate), and a median dissolved-bromide concentration of 0.08 milligrams per liter.
\nWater-quality data were grouped according to the depth and position of the wells in the flow system with respect to the closed industrial landfill. Shallow wells are those less than 100 feet deep; deep wells are those more than 100 feet deep. Comparison among groups indicates that water from shallow wells downgradient from the landfill had larger values of specific conductance, larger concentrations of alkalinity and dissolved bromide, and smaller values of pH than did water from shallow wells upgradient from the landfill and water from deep wells throughout the study area.
\nConcentrations of dissolved bromide were used to estimate the extent of the landfill's effect on ground-water quality by plotting and contouring the concentration values on maps and hydrogeologic sections. The maps show a plume of bromide extending south of the landfill along the direction of groundwater flow. The hydrogeologic sections indicate that water containing bromide is moving vertically downward in the unconfined aquifer beneath and downgrfldient from the landfill. Maps and sections for different time periods were compared to determine how the distribution of bromide was changing. Although dissolved-bromide concentrations in water from individual wells were variable, the distribution of dissolved bromide did not change substantially during the study period.
\nThe time of peak dissolved-bromide concentrations in water from shallow wells downgradient from the landfill was used to estimate a rate of horizontal flow of water in the unconfined aquifer. The average rate of flow between shallow wells downgradient from the landfill was estimated to be 1.2 feet per day. This rate is within the range of values for ground-water flow calculated according to Darcy's law.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Indianapolis, IN","doi":"10.3133/wri914053","collaboration":"Elkhart Water Works","usgsCitation":"Duwelius, R., and Silcox, C., 1991, Ground-water levels, flow, and quality in northwestern Elkhart County, Indiana, 1980-89: U.S. Geological Survey Water-Resources Investigations Report 91-4053, v, 66 p., https://doi.org/10.3133/wri914053.","productDescription":"v, 66 p.","numberOfPages":"71","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":346,"text":"Indiana Water Science Center","active":true,"usgs":true}],"links":[{"id":424355,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_47477.htm","linkFileType":{"id":5,"text":"html"}},{"id":121571,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1991/4053/report-thumb.jpg"},{"id":55780,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1991/4053/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"country":"United States","state":"Indiana","county":"Elkhart County","geographicExtents":"{\"type\":\"FeatureCollection\",\"features\":[{\"type\":\"Feature\",\"geometry\":{\"type\":\"Polygon\",\"coordinates\":[[[-85.7874,41.7615],[-85.7591,41.7613],[-85.6606,41.7608],[-85.6589,41.699],[-85.6575,41.6122],[-85.6554,41.5251],[-85.6542,41.4733],[-85.6552,41.4384],[-85.7704,41.4377],[-85.8874,41.4379],[-86.0008,41.4375],[-86.059,41.4367],[-86.0594,41.4644],[-86.0593,41.474],[-86.0593,41.479],[-86.0592,41.4935],[-86.0598,41.4999],[-86.0624,41.7619],[-85.932,41.7623],[-85.7874,41.7615]]]},\"properties\":{\"name\":\"Elkhart\",\"state\":\"IN\"}}]}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4aa8e4b07f02db667496","contributors":{"authors":[{"text":"Duwelius, R.F.","contributorId":28250,"corporation":false,"usgs":true,"family":"Duwelius","given":"R.F.","affiliations":[],"preferred":false,"id":197212,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Silcox, C.A.","contributorId":90778,"corporation":false,"usgs":true,"family":"Silcox","given":"C.A.","affiliations":[],"preferred":false,"id":197213,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":25671,"text":"wri904111 - 1991 - Methods, instrumentation, and preliminary evaluation of data for the hydrologic budget assessment of Lake Lucerne, Polk County, Florida","interactions":[],"lastModifiedDate":"2012-02-02T00:08:24","indexId":"wri904111","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"90-4111","title":"Methods, instrumentation, and preliminary evaluation of data for the hydrologic budget assessment of Lake Lucerne, Polk County, Florida","language":"ENGLISH","publisher":"U.S. Dept. of the Interior, U.S. Geological Survey ;\r\nBooks and Open-File Reports [distributor],","doi":"10.3133/wri904111","usgsCitation":"Lee, T.M., Adams, D.B., Tihansky, A., and Swancar, A., 1991, Methods, instrumentation, and preliminary evaluation of data for the hydrologic budget assessment of Lake Lucerne, Polk County, Florida: U.S. Geological Survey Water-Resources Investigations Report 90-4111, vi, 42 p. :ill., maps ;28 cm., https://doi.org/10.3133/wri904111.","productDescription":"vi, 42 p. :ill., maps ;28 cm.","costCenters":[],"links":[{"id":121891,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1990/4111/report-thumb.jpg"},{"id":54440,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1990/4111/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a56e4b07f02db62d5ef","contributors":{"authors":[{"text":"Lee, T. M.","contributorId":67855,"corporation":false,"usgs":true,"family":"Lee","given":"T.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":194594,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Adams, D. B.","contributorId":59030,"corporation":false,"usgs":true,"family":"Adams","given":"D.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":194593,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Tihansky, A. B. 0000-0003-1681-1601","orcid":"https://orcid.org/0000-0003-1681-1601","contributorId":77956,"corporation":false,"usgs":true,"family":"Tihansky","given":"A. B.","affiliations":[],"preferred":false,"id":194595,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Swancar, Amy aswancar@usgs.gov","contributorId":450,"corporation":false,"usgs":true,"family":"Swancar","given":"Amy","email":"aswancar@usgs.gov","affiliations":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"preferred":false,"id":194592,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":30446,"text":"wri894204 - 1991 - Hydrology of Lakes Clara and Vandercook in north-central Wisconsin","interactions":[],"lastModifiedDate":"2025-01-13T21:35:23.536972","indexId":"wri894204","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"89-4204","title":"Hydrology of Lakes Clara and Vandercook in north-central Wisconsin","docAbstract":"Lakes Clara and Vandercook are 33- and 43-hectare lakes, respectively, located in predominantly sandy outwash in north-central Wisconsin. Annual precipitation at National Weather Service stations during the 1951-80 calendar years averaged 794 millimeters near Lake Clara and 834 millimeters near Vandercook Lake. During the 1981 water year, annual precipitation measured at the lakes as part of this study was 3 percent below average for Lake Clara and 16 percent below average for Vandercook Lake. Annual precipitation was 6 to 21 percent above average for the two lakes during the 1982 and 1983 water years. Lake stage and water-table altitudes were relatively constant at Lake Clara throughout the 3 water years of study and at Vandercook Lake during the 1981 and 1982 water years; however, Vandercook Lake stage increased 0.2 meter, and the upgradient water table increased 0.3 meter, during the 1983 water year.
\nHydrologic budgets show that lake inflow was dominated by precipitation (77 to 91 percent for Lake Clara and 79 to 87 percent for Vandercook Lake). Ground water accounted for the remaining inflow to Vandercook Lake; however, Lake Clara received approximately equal contributions from ground-water inflow and overland flow. Evaporation was the major form of lake outflow (59 to 75 percent for Lake Clara and 59 to 63 percent for Vandercook Lake). The remaining outflow from Vandercook Lake was to the ground-water system, but Lake Clara lost approximately equal amounts by surface and ground-water outflow. Hydraulic residence times were 4 to 5 years for both lakes. Chemical residence times for conservative constituents were 11 to 21 years for Lake Clara and 10 to 13 years for Vandercook Lake.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/wri894204","collaboration":"Prepared in cooperation with the Wisconsin Department of Natural Resources","usgsCitation":"Wentz, D., and Rose, W.J., 1991, Hydrology of Lakes Clara and Vandercook in north-central Wisconsin: U.S. Geological Survey Water-Resources Investigations Report 89-4204, iv, 24 p., https://doi.org/10.3133/wri894204.","productDescription":"iv, 24 p.","numberOfPages":"28","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":677,"text":"Wisconsin Water Science Center","active":true,"usgs":true}],"links":[{"id":119548,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1989/4204/report-thumb.jpg"},{"id":59229,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1989/4204/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":466165,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_47280.htm","text":"Lake Clara","linkFileType":{"id":5,"text":"html"}},{"id":466166,"rank":4,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_47281.htm","text":"Lake Vandercook","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"Wisconsin","county":"Lincoln County, Vilas County","otherGeospatial":"Lake Clara, Lake Vandercook","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -89.6917,\n 45.9889\n ],\n [\n -89.6917,\n 45.975\n ],\n [\n -89.675,\n 45.975\n ],\n [\n -89.675,\n 45.9889\n ],\n [\n -89.6917,\n 45.9889\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n },\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -89.57684112300198,\n 45.51811623533976\n ],\n [\n -89.57684112300198,\n 45.50813456388167\n ],\n [\n -89.56724596836187,\n 45.50813456388167\n ],\n [\n -89.56724596836187,\n 45.51811623533976\n ],\n [\n -89.57684112300198,\n 45.51811623533976\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a17e4b07f02db604895","contributors":{"authors":[{"text":"Wentz, D.A.","contributorId":85206,"corporation":false,"usgs":true,"family":"Wentz","given":"D.A.","email":"","affiliations":[],"preferred":false,"id":203269,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rose, W. J.","contributorId":14433,"corporation":false,"usgs":true,"family":"Rose","given":"W.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":203268,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":38447,"text":"pp1406C - 1991 - Geochemistry of ground water in alluvial basins of Arizona and adjacent parts of Nevada, New Mexico, and California","interactions":[],"lastModifiedDate":"2012-02-02T00:10:00","indexId":"pp1406C","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":331,"text":"Professional Paper","code":"PP","onlineIssn":"2330-7102","printIssn":"1044-9612","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"1406","chapter":"C","title":"Geochemistry of ground water in alluvial basins of Arizona and adjacent parts of Nevada, New Mexico, and California","docAbstract":"Chemical and isotope analyses of ground water from 28 basins in the Basin and Range physiographic province of Arizona and parts of adjacent States were used to evaluate ground-water quality, determine processes that control ground-water chemistry, provide independent insight into the hydrologic flow system, and develop information transfer. The area is characterized by north- to northwest-trending mountains separated by alluvial basins that form a regional topography of alternating mountains and valleys. On the basis of ground-water divides or zones of minimal basin interconnection, the area was divided into 72 basins, each representing an individual aquifer system. These systems are joined in a dendritic pattern and collectively constitute the major water resource in the region. \r\n\r\nGeochemical models were developed to identify reactions and mass transfer responsible for the chemical evolution of the ground water. On the basis of mineralogy and chemistry of the two major rock associations of the area, a felsic model and a mafic model were developed to illustrate geologic, climatic, and physiographic effects on ground-water chemistry. Two distinct hydrochemical processes were identified: (1) reactions of meteoric water with minerals and gases in recharge areas and (2) reactions of ground water as it moves down the hydraulic gradient. Reactions occurring in recharge and downgradient areas can be described by a 13-component system. Major reactions are the dissolution and precipitation of calcite and dolomite, the weathering of feldspars and ferromagnesian minerals, the formation of montmorillonite, iron oxyhydroxides, and probably silica, and, in some basins, ion exchange. \r\n\r\nThe geochemical modeling demonstrated that relatively few phases are required to derive the ground-water chemistry; 14 phases-12 mineral and 2 gas-consistently account for the chemical evolution in each basin. The final phases were selected through analysis of X-ray diffraction and fluorescence data, aqueous speciation and saturation data, and mass-balance and isotopic constraints and through chemical models developed from mineral combinations among the 27 phases that were considered realistic in these geologically and mineralogically complex basins. X-ray diffraction of basin-fill sediments confirm the presence of the postulated minerals and their weathering sequences. \r\n\r\nHigh partial pressures of soil CO2 and large concentrations of dissolved CO2 in recharge areas, and the rapid depletion of CO2 downgradient, accompanied by high weathering rates of the silicates which also decrease downgradient, indicate that carbonic acid is the impetus in the weathering process. Reactions in the soil zone and the unsaturated zone are influential and, in some instances, are as important as the mineralogy of the source rock in determining ground-water compositions. \r\n\r\nThe basins can be divided geochemically into two general categories-closed systems, which evolve under closed hydrologic conditions, and open systems, which are open to CO2 and other constituents along the flow path. The ground-water chemistry of the unconfined aquifers in the eastern part of the study area and of the aquifers underlying the flood plain along the Colorado River generally evolves under open conditions. The ground-water chemistry of most basins in the central and western parts and of the confined aquifers in the eastern part evolves under closed conditions. The factors that determine whether a basin is an open or closed system are the amount of and the spatial and seasonal distribution of annual precipitation and the presence or absence of fine-grained confining units. \r\n\r\nThe basins along the Colorado River are unique among basins in the region. Virtually all ground water underlying the flood plain originated as seepage or overbank flow from the Colorado River. Initial deuterium content of about -120 per mil is indicative of precipitation from the central part of Colorado. Using chemical m","language":"ENGLISH","doi":"10.3133/pp1406C","usgsCitation":"Robertson, F.N., 1991, Geochemistry of ground water in alluvial basins of Arizona and adjacent parts of Nevada, New Mexico, and California: U.S. Geological Survey Professional Paper 1406, p. C1-C90, https://doi.org/10.3133/pp1406C.","productDescription":"p. C1-C90","costCenters":[],"links":[{"id":119769,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/pp/1406c/report-thumb.jpg"},{"id":64922,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/pp/1406c/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b1fe4b07f02db6aad69","contributors":{"authors":[{"text":"Robertson, Frederick N.","contributorId":108160,"corporation":false,"usgs":true,"family":"Robertson","given":"Frederick","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":219838,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":28835,"text":"wri884230 - 1991 - Hydrology, water quality, and simulation of ground-water flow at a taconite-tailings basin near Keewatin, Minnesota","interactions":[],"lastModifiedDate":"2018-03-19T10:33:44","indexId":"wri884230","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"88-4230","title":"Hydrology, water quality, and simulation of ground-water flow at a taconite-tailings basin near Keewatin, Minnesota","docAbstract":"Taconite tailings, a waste product from processing of iron ore, have been deposited in a 2.5-square-mile containment basin near Keewatin, Minnesota, The basin, which is bounded by earthen dikes of compacted drift and clayey bouldery till, contains saturated tailings consisting of chert and other silica-rich particles that range from clay to coarse-sand size.
\nRunoff from the tailings is slight and occurs only after heavy rains and snowmelt. Average discharge from the basin from April 1982 through June 1984 was about 0.6 cubic foot per second. Instantaneous discharge ranged from zero during much of the period to about 140 cubic feet per second following snowmelt in spring 1982. Daily mean discharge from the basin exceeded 20 cubic feet per second on two days during the period of study.
\nWater levels in wells range from 0 to 25 feet below the tailings surface; seasonal fluctuations range from 2 to 8 feet. Ground water flows radially from a mound in the north-central part of the basin under a hydraulic gradient of 4.7 x 10-3 feet per foot. Vertical flow also is downward to drift deposits beneath the tailings. Vertical gradients range from 7.0 x 10-3 to 6.0 x 10-1 feet per foot.
\nSaturated thickness of the tailings ranges from about 1 to 35 feet. Estimated horizontal hydraulic conductivity ranges from about 1 to 500 feet per day. Transmissivities range from about 25 feet squared per day in fine tailings to about 350 feet squared per day in coarse tailings. Ground-water recharge from precipitation was 11.8 inches from October 1982 through September 1983. Ground-water outflow as leakage to the underlying drift deposits was 9.9 inches for the same period.
\nWater collected from wells completed in the tailings and from the drainage ditch at the basin outlet is of a mixed type in which the magnesium concentration only slightly exceeds concentrations of calcium and sodium plus potassium, expressed in milliequivalents, and concentrations of sulfate and bicarbonate, expressed in milliequivalents, are equal. Concentrations of arsenic, fluoride, and nitrite plus nitrate in water from the tailings were notably greater than in water from adjacent aquifers. However, only fluoride, manganese, and nitrite plus nitrate concentrations equalled or exceeded State drinking-water standards. Suspended-sediment concentrations in streamflow ranged from less than 1 milligram per liter during low-flow periods to about 4,600 milligrams per liter following snowmelt in the spring of 1982.
\nNumerical-model simulations of ground-water flow near the vicinity of the tailings basin indicate that, if areal recharge were doubled during spring and fall, water levels in wells could average about 4 feet above 1983 levels during these periods. Model results indicate that water levels in the tailings could possibly remain about 5 feet above 1983 levels at the end of the year. Water levels in the tailings at the outlet of the basin could be about 1 foot above 1983 levels during the spring stress period and could be nearly 1.5 feet above 1983 levels during the fall stress period. Under these hypothetical climatic conditions, ground-water contribution to discharge at the outlet could be about 50 cubic feet per second during spring and about 80 cubic feet per second during fall.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"St. Paul, MN","doi":"10.3133/wri884230","collaboration":"Prepared in cooperation with the Iron Range Resources and Rehabilitation Board and the Minnesota Pollution Control Agency","usgsCitation":"Myette, C., 1991, Hydrology, water quality, and simulation of ground-water flow at a taconite-tailings basin near Keewatin, Minnesota: U.S. Geological Survey Water-Resources Investigations Report 88-4230, vi, 61 p., https://doi.org/10.3133/wri884230.","productDescription":"vi, 61 p.","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":392,"text":"Minnesota Water Science Center","active":true,"usgs":true}],"links":[{"id":57711,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1988/4230/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":122981,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1988/4230/report-thumb.jpg"}],"country":"United States","state":"Minnesota","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -93.083333,\n 47.404167\n ],\n [\n -93.083333,\n 47.358333\n ],\n [\n -93,\n 47.358333\n ],\n [\n -93,\n 47.404167\n ],\n [\n -93.083333,\n 47.404167\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4afde4b07f02db696c0f","contributors":{"authors":[{"text":"Myette, C. F.","contributorId":97115,"corporation":false,"usgs":true,"family":"Myette","given":"C. F.","affiliations":[],"preferred":false,"id":200482,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70162175,"text":"70162175 - 1991 - Time-courses in the retention of food material in the bivalves Potamocorbula amurensis and Macoma balthica significance to the absorption of carbon and chromium","interactions":[],"lastModifiedDate":"2019-03-28T06:22:18","indexId":"70162175","displayToPublicDate":"1992-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2663,"text":"Marine Ecology Progress Series","active":true,"publicationSubtype":{"id":10}},"title":"Time-courses in the retention of food material in the bivalves Potamocorbula amurensis and Macoma balthica significance to the absorption of carbon and chromium","docAbstract":"Time courses for ingestion, retention and release via feces of microbial food was investigated using 2 bivalves with different feeding strategies, Potamocorbula amurensis and Macoma balthica. The results showed 2 pathways for the uptake of food material in these clams. The first is represented by an initial label pulse in the feces. The second pathway operates over longer time periods. Inert 51Cr-labeled beads were used to determine time frames for these pathways. The first pathway, involving extracellular digestion and intestinal uptake, is relatively inefficient in the digestion of bacterial cells by P. amurensis but more efficient in M. balthica. The second pathway, involving intracellular digestion within the digestive gland of both clams, was highly efficient in absorbing bacterial carbon, and was responsible for most chromium uptake. Differences in the overall retention of microbial 51Cr and 14C relate not to gut-passage times but to the processing and release strategies of the food material by these 2 clams.
","language":"English","publisher":"Inter Research","usgsCitation":"Decho, A.W., and Luoma, S.N., 1991, Time-courses in the retention of food material in the bivalves Potamocorbula amurensis and Macoma balthica significance to the absorption of carbon and chromium: Marine Ecology Progress Series, v. 78, p. 303-314.","productDescription":"12 p.","startPage":"303","endPage":"314","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":314360,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":314359,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://www.int-res.com/abstracts/meps/v78/"}],"volume":"78","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5698d4d3e4b0fbd3f7fa4c6f","contributors":{"authors":[{"text":"Decho, Alan W.","contributorId":22107,"corporation":false,"usgs":true,"family":"Decho","given":"Alan","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":588765,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Luoma, Samuel N. 0000-0001-5443-5091 snluoma@usgs.gov","orcid":"https://orcid.org/0000-0001-5443-5091","contributorId":2287,"corporation":false,"usgs":true,"family":"Luoma","given":"Samuel","email":"snluoma@usgs.gov","middleInitial":"N.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":588766,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70126465,"text":"70126465 - 1991 - A modeling assessment of the thermal regime for an urban sport fishery","interactions":[],"lastModifiedDate":"2014-09-23T11:24:46","indexId":"70126465","displayToPublicDate":"1991-11-01T11:21:06","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1547,"text":"Environmental Management","active":true,"publicationSubtype":{"id":10}},"title":"A modeling assessment of the thermal regime for an urban sport fishery","docAbstract":"Water temperature is almost certainly a limiting factor in the maintenance of a self-sustaining rainbow trout (Oncorhynchus mykiss, formerly Salmo gairdneri) and brown trout (Salmo trutta) fishery in the lower reaches of the Cache la Poudre River near Fort Collins, Colorado, USA. Irrigation diversions dewater portions of the river, but cold reservoir releases moderate water temperatures during some periods. The US Fish and Wildlife Service’s Stream Network Temperature Model (SNTEMP) was applied to a 31-km segment of the river using readily available stream geometry and hydrological and meteorological data. The calibrated model produced satisfactory water temperature predictions (R2=0.88,P<0.001, N=49) for a 62-day summer period. It was used to evaluate a variety of flow and nonflow alternatives to keep water temperatures below 23.3°C for the trout. Supplemental flows or reduced diversions of 3 m3/sec would be needed to maintain suitable summer temperatures throughout most of the study area. Such flows would be especially beneficial during weekends when current irrigation patterns reduce flows. The model indicated that increasing the riparian shade would result in little improvement in water temperatures but that decreasing the stream width would result in significant temperature reductions. Introduction of a more thermally tolerant redband trout (Oncorhynchus sp.), or smallmouth bass (Micropterus dolomieui) might prove beneficial to the fishery. Construction of deep pools for thermal refugia might also be helpful.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Management","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Springer-Verlag","publisherLocation":"New York","doi":"10.1007/BF02394821","usgsCitation":"Bartholow, J.M., 1991, A modeling assessment of the thermal regime for an urban sport fishery: Environmental Management, v. 15, no. 6, p. 833-845, https://doi.org/10.1007/BF02394821.","productDescription":"13 p.","startPage":"833","endPage":"845","numberOfPages":"13","costCenters":[],"links":[{"id":294317,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":294316,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF02394821"}],"volume":"15","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5422bb07e4b08312ac7ceeb1","contributors":{"authors":[{"text":"Bartholow, John M.","contributorId":77598,"corporation":false,"usgs":true,"family":"Bartholow","given":"John","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":502067,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70126917,"text":"70126917 - 1991 - Global warming and prairie wetlands: potential consequences for waterfowl habitat","interactions":[],"lastModifiedDate":"2014-09-25T09:49:44","indexId":"70126917","displayToPublicDate":"1991-10-01T09:29:53","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":997,"text":"BioScience","active":true,"publicationSubtype":{"id":10}},"title":"Global warming and prairie wetlands: potential consequences for waterfowl habitat","docAbstract":"The accumulation of greenhouse gasses in the atmosphere is expected to warm the earth's climate at an unprecedented rate (Ramanathan 1988, Schneider 1989). If the climate models are correct, within 100 years the earth will not only be warmer than it has been during the past million years, but the change will have occurred more rapidly than any on record. Many profound changes in the earth's environment are expected, including rising sea level, increasing aridity in continental interiors, and melting permafrost.
\nEcosystems are expected to respond variously to a rapidly changing climate. Tree ranges in eastern North American are expected to shift northward, and seed dispersal may not be adequate to maintain current diversity (Cohn 1989, Johnson and Webb 1989). In coastal wetlands, rising sea level from melting icecaps and thermal expansion could flood salt-grass marshes and generally reduce the size and productivity of the intertidal zone (Peters and Darling 1985).
\nAs yet, little attention has been given to the possible effects of climatic warming on inland prairie wetland ecosystems. These wetlands, located in the glaciated portion of the North American Great Plains (Figure 1), constitute the single most important breeding area for waterfowl on this continent (Hubbard 1988). This region annually produces 50-80% of the continent's total duck production (Batt et al. 1989). These marshes also support a variety of other wildlife, including many species of nongame birds, muskrat, and mink (Kantrud et al. 1989a).
\nPrairie wetlands are relatively shallow, water-holding depressions that vary in size, water permanence, and water chemistry. Permanence types include temporary ponds (typically holding water for a few weeks in the springs), seasonal ponds (holding water from spring until early summer), semipermanent ponds (holding water throughout the growing season during most years), and large permanent lakes (Stewart and Kantrud 1971). Refilling usually occurs in spring from precipitation and runoff from melting snow on frozen or saturated soils (Figure 2). Annual water levels fluctuate widely due to climate variability in the Great Plains (Borchert 1950, Kantrud et al. 1989b).
\nClimate affects the quality of habitat for breeding waterfowl by controlling regional water conditions--water depth, areal extent, and length of wet/dry cycles (Cowardin et al. 1988)--and vegetation patterns such as the cover ration (the ratio of emergent plant cover to open water). With increased levels of atmospheric carbon dioxide, climate models project warmer and, in some cases, drier conditions for the northern Great Plains (Karl et al. 1991, Manabe and Wetherald 1986, Mitchell 1983, Rind and Lebedeff 1984). In general, a warmer, drier climate could lower waterfowl production directly by increasing the frequency of dry basins and indirectly by producing less favorable cover rations (i.e., heavy emergent cover with few or no open-water areas).
\nThe possibility of diminished waterfowl production in a greenhouse climate comes at a time when waterfowl numbers have sharply declined for other reasons (Johnson and Shaffer 1987). Breeding habitat continues to be lost or altered by agriculture, grazing, burning, mowing, sedimentation, and drainage (Kantrud et al. 1989b). For example, it has been estimated that 60% of the wetland area in North Dakota has been drained (Tiner 1984). Pesticides entering wetlands from adjacent agricultural fields have been destructive to aquatic invertebrate populations and have significantly lowered duckling survival (Grue et al. 1988).
\nIn this article, we discuss current understanding and projections of global warming; review wetland vegetation dynamics to establish the strong relationship among climate, wetland hydrology, vegetation patterns, and waterflow habitat; discuss the potential effects of a greenhouse warming on these relationships; and illustrate the potential effects of climate change on wetland habitat by using a simulation model.
\nThe extent to which intensive management of the waterfowl resource will be needed in the future strongly depends on whether a changing climate exacerbates the current problem of waterfowl decline. Should this occur, efforts outlined the recent North American Waterfowl Management Plan between the United States and Canada to reduce the current decline (Patterson and Nelson 1988) may need to be redoubled in coming years.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"BioScience","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"American Institute of Biological Sciences","publisherLocation":"Washington, D.C.","doi":"10.2307/1311698","usgsCitation":"Poiani, K.A., and Johnson, W., 1991, Global warming and prairie wetlands: potential consequences for waterfowl habitat: BioScience, v. 41, no. 9, p. 611-618, https://doi.org/10.2307/1311698.","productDescription":"8 p.","startPage":"611","endPage":"618","numberOfPages":"8","costCenters":[],"links":[{"id":294462,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":294461,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.2307/1311698"}],"volume":"41","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"54252eb5e4b0e641df8a6ffa","contributors":{"authors":[{"text":"Poiani, Karen A.","contributorId":57385,"corporation":false,"usgs":true,"family":"Poiani","given":"Karen","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":502194,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Johnson, W. Carter","contributorId":97237,"corporation":false,"usgs":true,"family":"Johnson","given":"W. Carter","affiliations":[],"preferred":false,"id":502195,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70185806,"text":"70185806 - 1991 - Ground-penetrating radar: A tool for mapping reservoirs and lakes","interactions":[],"lastModifiedDate":"2019-03-28T06:31:10","indexId":"70185806","displayToPublicDate":"1991-10-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2456,"text":"Journal of Soil and Water Conservation","active":true,"publicationSubtype":{"id":10}},"title":"Ground-penetrating radar: A tool for mapping reservoirs and lakes","docAbstract":"Ground-penetrating radar was evaluated as a tool for mapping reservoir and lake bottoms and providing stage-storage information. An impulse radar was used on a 1.4-ha (3.5-acre) reservoir with 31 transects located 6.1 m (20 feet) apart. Depth of water and lateral extent of the lake bottom were accurately measured by ground-penetrating radar. A linear (positive) relationship existed between measured water depth and ground-penetrating radar-determined water depth (R2=0.989). Ground-penetrating radar data were used to create a contour map of the lake bottom. Relationships between water (contour) elevation and water surface area and volume were established. Ground-penetrating radar proved to be a useful tool for mapping lakes, detecting lake bottom variations, locating old stream channels, and determining water depths. The technology provides accurate, continuous profile data in a relatively short time compared to traditional surveying and depth-sounding techniques.
","language":"English","publisher":"Soil and Water Conservation Society","usgsCitation":"Truman, C., Asmussen, L., and Allison, H., 1991, Ground-penetrating radar: A tool for mapping reservoirs and lakes: Journal of Soil and Water Conservation, v. 46, no. 5, p. 370-373.","productDescription":"4 p. ","startPage":"370","endPage":"373","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338566,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":338565,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://www.jswconline.org/content/46/5/370.abstract"}],"volume":"46","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58dcc81fe4b02ff32c68572a","contributors":{"authors":[{"text":"Truman, C.C.","contributorId":190010,"corporation":false,"usgs":false,"family":"Truman","given":"C.C.","email":"","affiliations":[],"preferred":false,"id":686780,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Asmussen, L.E.","contributorId":16276,"corporation":false,"usgs":true,"family":"Asmussen","given":"L.E.","email":"","affiliations":[],"preferred":false,"id":686781,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Allison, H.D.","contributorId":190009,"corporation":false,"usgs":false,"family":"Allison","given":"H.D.","email":"","affiliations":[],"preferred":false,"id":686782,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70185492,"text":"70185492 - 1991 - Geochemistry of dissolved inorganic carbon in a Coastal Plain aquifer. 2. Modeling carbon sources, sinks, and δ13C evolution","interactions":[],"lastModifiedDate":"2017-03-22T14:35:17","indexId":"70185492","displayToPublicDate":"1991-10-01T00:00:00","publicationYear":"1991","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":"Geochemistry of dissolved inorganic carbon in a Coastal Plain aquifer. 2. Modeling carbon sources, sinks, and δ13C evolution","docAbstract":"Stable isotope data for dissolved inorganic carbon (DIC), carbonate shell material and cements, and microbial CO2 were combined with organic and inorganic chemical data from aquifer and confining-bed pore waters to construct geochemical reaction models along a flowpath in the Black Creek aquifer of South Carolina. Carbon-isotope fractionation between DIC and precipitating cements was treated as a Rayleigh distillation process. Organic matter oxidation was coupled to microbial fermentation and sulfate reduction. All reaction models reproduced the observed chemical and isotopic compositions of final waters. However, model 1, in which all sources of carbon and electron-acceptors were assumed to be internal to the aquifer, was invalidated owing to the large ratio of fermentation CO2 to respiration CO2 predicted by the model (5–49) compared with measured ratios (two or less). In model 2, this ratio was reduced by assuming that confining beds adjacent to the aquifer act as sources of dissolved organic carbon and sulfate. This assumption was based on measured high concentrations of dissolved organic acids and sulfate in confining-bed pore waters (60–100 μM and 100–380 μM, respectively) relative to aquifer pore waters (from less than 30 μM and 2–80 μM, respectively). Sodium was chosen as the companion ion to organic-acid and sulfate transport from confining beds because it is the predominant cation in confining-bed pore waters. As a result, excessive amounts of Na-for-Ca ion exchange and calcite precipitation (three to four times more cement than observed in the aquifer) were required by model 2 to achieve mass and isotope balance of final water. For this reason, model 2 was invalidated. Agreement between model-predicted and measured amounts of carbonate cement and ratios of fermentation CO2 to respiration CO2 were obtained in a reaction model that assumed confining beds act as sources of DIC, as well as organic acids and sulfate. This assumption was supported by measured high concentrations of DIC in confining beds (2.6–2.7 mM). Results from this study show that geochemical models of confined aquifer systems must incorporate the effects of adjacent confining beds to reproduce observed groundwater chemistry accurately.
","language":"English","publisher":"Elseiver","doi":"10.1016/0022-1694(91)90111-T","usgsCitation":"McMahon, P.B., and Chapelle, F.H., 1991, Geochemistry of dissolved inorganic carbon in a Coastal Plain aquifer. 2. Modeling carbon sources, sinks, and δ13C evolution: Journal of Hydrology, v. 127, no. 1-4, p. 109-135, https://doi.org/10.1016/0022-1694(91)90111-T.","productDescription":"27 p. ","startPage":"109","endPage":"135","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338088,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"South Carolina","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -81.91955566406249,\n 33.38099943104024\n ],\n [\n -81.903076171875,\n 33.33511774753217\n ],\n [\n -81.80419921875,\n 33.224903086263964\n ],\n [\n -81.551513671875,\n 33.063924198120645\n ],\n [\n -81.4141845703125,\n 32.8149783969858\n ],\n [\n -81.3922119140625,\n 32.60698915452777\n ],\n [\n -81.199951171875,\n 32.47732919639942\n ],\n [\n -81.123046875,\n 32.091882620021806\n ],\n [\n -80.8319091796875,\n 31.94750122367064\n ],\n [\n -79.9749755859375,\n 32.560703522325156\n ],\n [\n -79.156494140625,\n 33.19273094190692\n ],\n [\n -78.5577392578125,\n 33.8521697014074\n ],\n [\n -79.5025634765625,\n 34.66935854524543\n ],\n [\n -80.4583740234375,\n 34.252676117101515\n ],\n [\n -81.91955566406249,\n 33.38099943104024\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"127","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58d38d61e4b0236b68f98f76","contributors":{"authors":[{"text":"McMahon, Peter B. 0000-0001-7452-2379 pmcmahon@usgs.gov","orcid":"https://orcid.org/0000-0001-7452-2379","contributorId":724,"corporation":false,"usgs":true,"family":"McMahon","given":"Peter","email":"pmcmahon@usgs.gov","middleInitial":"B.","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"preferred":true,"id":685729,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chapelle, Francis H. chapelle@usgs.gov","contributorId":1350,"corporation":false,"usgs":true,"family":"Chapelle","given":"Francis","email":"chapelle@usgs.gov","middleInitial":"H.","affiliations":[{"id":559,"text":"South Carolina Water Science Center","active":true,"usgs":true},{"id":13634,"text":"South Atlantic Water Science Center","active":true,"usgs":true}],"preferred":true,"id":685730,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70125922,"text":"70125922 - 1991 - Hydrologic pathways and chemical composition of runoff during snowmelt in Loch Vale Watershed, Rocky Mountain National Park, Colorado, USA","interactions":[],"lastModifiedDate":"2018-02-21T17:43:35","indexId":"70125922","displayToPublicDate":"1991-09-01T09:22:19","publicationYear":"1991","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":"Hydrologic pathways and chemical composition of runoff during snowmelt in Loch Vale Watershed, Rocky Mountain National Park, Colorado, USA","docAbstract":"Intensive sampling of a stream draining an alpine-subalpine basin revealed that depressions in pH and acid neutralizing capacity (ANC) of surface water at the beginning of the spring snowmelt in 1987 and 1988 were not accompanied by increases in strong acid anions, and that surface waters did not become acidic (ANC<0). Samples of meltwater collected at the base of the snowpack in 1987 were acidic and exhibited distinct ‘pulses’ of nitrate and sulfate. Solutions collected with lysimeters in forest soils adjacent to the stream revealed high levels of dissolved organic carbon (DOC) and total Al. Peaks in concentration of DOC, Al, and nutrient species in the stream samples indicate a flush of soil solution into the surface water at the beginning of the melt. Infiltration of meltwater into soils and spatial heterogeneity in the timing of melting across the basin prevented stream and lake waters from becoming acidic.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Water, Air, and Soil Pollution","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Kluwer Academic Publishers","publisherLocation":"Dordrecht","doi":"10.1007/BF00283175","usgsCitation":"Denning, A.S., Baron, J., Mast, M.A., and Arthur, M., 1991, Hydrologic pathways and chemical composition of runoff during snowmelt in Loch Vale Watershed, Rocky Mountain National Park, Colorado, USA: Water, Air, & Soil Pollution, v. 59, no. 1-2, p. 107-123, https://doi.org/10.1007/BF00283175.","productDescription":"17 p.","startPage":"107","endPage":"123","numberOfPages":"17","costCenters":[],"links":[{"id":294095,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00283175"},{"id":294096,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","otherGeospatial":"Rocky Mountain National Park","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -105.913714,40.158067 ], [ -105.913714,40.553787 ], [ -105.493583,40.553787 ], [ -105.493583,40.158067 ], [ -105.913714,40.158067 ] ] ] } } ] }","volume":"59","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"541bf432e4b0e96537ddf722","contributors":{"authors":[{"text":"Denning, A. Scott","contributorId":70710,"corporation":false,"usgs":true,"family":"Denning","given":"A.","email":"","middleInitial":"Scott","affiliations":[],"preferred":false,"id":501689,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Baron, Jill 0000-0002-5902-6251 jill_baron@usgs.gov","orcid":"https://orcid.org/0000-0002-5902-6251","contributorId":194124,"corporation":false,"usgs":true,"family":"Baron","given":"Jill","email":"jill_baron@usgs.gov","affiliations":[{"id":291,"text":"Fort Collins Science Center","active":true,"usgs":true}],"preferred":true,"id":501690,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mast, M. Alisa 0000-0001-6253-8162 mamast@usgs.gov","orcid":"https://orcid.org/0000-0001-6253-8162","contributorId":827,"corporation":false,"usgs":true,"family":"Mast","given":"M.","email":"mamast@usgs.gov","middleInitial":"Alisa","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"preferred":true,"id":501688,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Arthur, Mary","contributorId":99484,"corporation":false,"usgs":true,"family":"Arthur","given":"Mary","email":"","affiliations":[],"preferred":false,"id":501691,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70171484,"text":"70171484 - 1991 - Water-resources development and its influence on the water budget for the aquifer system in the Salinas to Patillas area","interactions":[],"lastModifiedDate":"2016-06-02T10:29:51","indexId":"70171484","displayToPublicDate":"1991-07-17T14:30:00","publicationYear":"1991","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Water-resources development and its influence on the water budget for the aquifer system in the Salinas to Patillas area","largerWorkType":{"id":24,"text":"Conference Paper"},"largerWorkTitle":"Regional aquifer systems of the United States, aquifers of the Caribbean Islands : papers presented at AWRA International Symposium on Tropical Hydrology","largerWorkSubtype":{"id":19,"text":"Conference Paper"},"conferenceTitle":"International Symposium on Tropical Hydrology","conferenceDate":"July 23-27, 1990","conferenceLocation":"San Juan, Puerto Rico","publisher":"American Water Resources Association","publisherLocation":"Bethesda, MD","usgsCitation":"Quinones-Aponte, V., 1991, Water-resources development and its influence on the water budget for the aquifer system in the Salinas to Patillas area, in Regional aquifer systems of the United States, aquifers of the Caribbean Islands : papers presented at AWRA International Symposium on Tropical Hydrology, San Juan, Puerto Rico, July 23-27, 1990, p. 37-55.","productDescription":"19 p.","startPage":"37","endPage":"55","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":156,"text":"Caribbean Water Science Center","active":true,"usgs":true}],"links":[{"id":322027,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"57500786e4b0ee97d51bb854","contributors":{"editors":[{"text":"Gomez-Gomez, Fernando","contributorId":169637,"corporation":false,"usgs":false,"family":"Gomez-Gomez","given":"Fernando","email":"","affiliations":[],"preferred":false,"id":631270,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"Johnson, A.I.","contributorId":82676,"corporation":false,"usgs":true,"family":"Johnson","given":"A.I.","email":"","affiliations":[],"preferred":false,"id":631271,"contributorType":{"id":2,"text":"Editors"},"rank":2}],"authors":[{"text":"Quinones-Aponte, Vicente","contributorId":48552,"corporation":false,"usgs":true,"family":"Quinones-Aponte","given":"Vicente","email":"","affiliations":[],"preferred":false,"id":631268,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70185485,"text":"70185485 - 1991 - Quartz dissolution in organic-rich aqueous systems","interactions":[],"lastModifiedDate":"2017-03-22T13:59:31","indexId":"70185485","displayToPublicDate":"1991-07-01T00:00:00","publicationYear":"1991","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":"Quartz dissolution in organic-rich aqueous systems","docAbstract":"Organic electrolytes are a common component of natural waters and are known to be important in many rock-water interactions. The influence of organic electrolytes on silica mobility, quartz solubility, and quartz dissolution kinetics, however, is less well understood. While there is mounting evidence supporting the presence of an aqueous organic-silica complex in natural waters, the significance of this species is difficult to characterize because of competing interactions in mixed inorganic-organic electrolyte environments. In the experiments reported here, the kinetics of quartz dissolution in dilute aqueous organic-acid solutions between 25 and 70°C were investigated to determine the influence of both organic and inorganic electrolytes.
Batch-reactor dissolution experiments in inorganic and organic electrolyte solutions were designed to investigate the hypothesis that organic acids at circum-neutral pH accelerate the dissolution and increase the solubility of quartz in water. Results suggest that multi-functional organic acids such as citrate and oxalate accelerate quartz dissolution by decreasing the activation energy by approximately 20%. The increase in dissolution rate was accompanied by a 100% increase in apparent quartz solubility at 25°C. Experiments using inorganic electrolytes, in contrast, increase the rate of quartz dissolution without decreasing the activation energy, and without increasing solubility.
From these data, a model for both a solution complex between dissolved organic acid and monomeric silicic acid, and an activated complex on quartz surfaces is proposed. The model suggests that dissolved organic compounds in natural waters at near-neutral pH and low temperatures are capable of accelerating the dissolution of quartz and increasing its solubility.
","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(91)90023-X","usgsCitation":"Bennett, P.C., 1991, Quartz dissolution in organic-rich aqueous systems: Geochimica et Cosmochimica Acta, v. 55, no. 7, p. 1781-1797, https://doi.org/10.1016/0016-7037(91)90023-X.","productDescription":"17 p. ","startPage":"1781","endPage":"1797","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338078,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"55","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58d38d61e4b0236b68f98f78","contributors":{"authors":[{"text":"Bennett, Philip C.","contributorId":30567,"corporation":false,"usgs":true,"family":"Bennett","given":"Philip","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":685705,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70185807,"text":"70185807 - 1991 - Evaluation of hydraulic conductivities calculated from multi-port permeameter measurements","interactions":[],"lastModifiedDate":"2017-03-29T11:07:39","indexId":"70185807","displayToPublicDate":"1991-07-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3825,"text":"Groundwater","active":true,"publicationSubtype":{"id":10}},"title":"Evaluation of hydraulic conductivities calculated from multi-port permeameter measurements","docAbstract":"A multiport permeameter was developed for use in estimating hydraulic conductivity over intact sections of aquifer core using the core liner as the permeameter body. Six cores obtained from one borehole through the upper 9 m of a stratified glacial-outwash aquifer were used to evaluate the reliability of the permeameter. Radiographs of the cores were used to assess core integrity and to locate 5- to 10-cm sections of similar grain size for estimation of hydraulic conductivity. After extensive testing of the permeameter, hydraulic conductivities were determined for 83 sections of the six cores. Other measurement techniques included permeameter measurements on repacked sections of core, estimates based on grain-size analyses, and estimates based on borehole flowmeter measurements. Permeameter measurements of 33 sections of core that had been extruded, homogenized, and repacked did not differ significantly from the original measurements. Hydraulic conductivities estimated from grain-size distributions were slightly higher than those calculated from permeameter measurements; the significance of the difference depended on the estimating equation used. Hydraulic conductivities calculated from field measurements, using a borehole flowmeter in the borehole from which the cores were extracted, were significantly higher than those calculated from laboratory measurements and more closely agreed with independent estimates of hydraulic conductivity based on tracer movement near the borehole. This indicates that hydraulic conductivities based on laboratory measurements of core samples may underestimate actual field hydraulic conductivities in this type of stratified glacial-outwash aquifer.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.1991.tb00543.x","usgsCitation":"Wolf, S.H., Celia, M.A., and Hess, K.M., 1991, Evaluation of hydraulic conductivities calculated from multi-port permeameter measurements: Groundwater, v. 29, no. 4, p. 516-525, https://doi.org/10.1111/j.1745-6584.1991.tb00543.x.","productDescription":"10 p. ","startPage":"516","endPage":"525","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338567,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"29","issue":"4","noUsgsAuthors":false,"publicationDate":"2005-08-04","publicationStatus":"PW","scienceBaseUri":"58dcc81fe4b02ff32c68572c","contributors":{"authors":[{"text":"Wolf, Steven H.","contributorId":189682,"corporation":false,"usgs":false,"family":"Wolf","given":"Steven","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":686783,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Celia, Michael A.","contributorId":189683,"corporation":false,"usgs":false,"family":"Celia","given":"Michael","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":686784,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hess, Kathryn M.","contributorId":49012,"corporation":false,"usgs":true,"family":"Hess","given":"Kathryn","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":686785,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70170198,"text":"70170198 - 1991 - Mechanisms controlling the transport of organic chemicals in subsurface environments","interactions":[],"lastModifiedDate":"2018-02-14T11:26:07","indexId":"70170198","displayToPublicDate":"1991-06-01T12:45:00","publicationYear":"1991","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Mechanisms controlling the transport of organic chemicals in subsurface environments","docAbstract":"No abstract available.
","largerWorkType":{"id":18,"text":"Report"},"largerWorkTitle":"U.S. Geological Survey Toxic Substances Hydrology Program---Proceedings of the technical meeting, Monterey, California, March 11-15, 1991","largerWorkSubtype":{"id":5,"text":"USGS Numbered Series"},"language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","usgsCitation":"Aiken, G., Capel, P., Furlong, E., Hult, M.F., and Thorn, K.A., 1991, Mechanisms controlling the transport of organic chemicals in subsurface environments, chap. of U.S. Geological Survey Toxic Substances Hydrology Program---Proceedings of the technical meeting, Monterey, California, March 11-15, 1991, p. 633-637.","productDescription":"5 p.","startPage":"633","endPage":"637","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":392,"text":"Minnesota Water Science Center","active":true,"usgs":true}],"links":[{"id":319957,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"570ccab6e4b0ef3b7ca14723","contributors":{"authors":[{"text":"Aiken, G. R. 0000-0001-8454-0984","orcid":"https://orcid.org/0000-0001-8454-0984","contributorId":14452,"corporation":false,"usgs":true,"family":"Aiken","given":"G. R.","affiliations":[],"preferred":false,"id":626367,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Capel, P. D. 0000-0003-1620-5185","orcid":"https://orcid.org/0000-0003-1620-5185","contributorId":95498,"corporation":false,"usgs":true,"family":"Capel","given":"P. D.","affiliations":[],"preferred":false,"id":626368,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"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":626369,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hult, M. F.","contributorId":29817,"corporation":false,"usgs":true,"family":"Hult","given":"M.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":626370,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Thorn, K. A.","contributorId":33294,"corporation":false,"usgs":true,"family":"Thorn","given":"K.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":626371,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70185494,"text":"70185494 - 1991 - Centrifugal techniques for measuring saturated hydraulic conductivity","interactions":[],"lastModifiedDate":"2018-02-27T11:49:07","indexId":"70185494","displayToPublicDate":"1991-06-01T00:00:00","publicationYear":"1991","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":"Centrifugal techniques for measuring saturated hydraulic conductivity","docAbstract":"Centrifugal force is an alternative to large pressure gradients for the measurement of low values of saturated hydraulic conductivity (Ksat). With a head of water above a porous medium in a centrifuge bucket, both constant-head and falling-head measurements are practical at forces up to at least 1800 times normal gravity. Darcy's law applied to the known centrifugal potential leads to simple formulas for Ksat that are analogous to those used in the standard gravity-driven constant- and falling-head methods. Both centrifugal methods were tested on several fine-textured samples of soil and ceramic with Ksat between about 10−10 and 10−9 m/s. The results were compared to falling-head gravity measurements. The comparison shows most measurements agreeing to within 20% for a given sample, much of the variation probably resulting from run-to-run changes in sample structure. The falling-head centrifuge method proved to be especially simple in design and operation and was more accurate than the constant-head method. With modified apparatus, Ksat measurements less than 10−10 m/s should be attainable.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/91WR00367","usgsCitation":"Nimmo, J.R., and Mello, K.A., 1991, Centrifugal techniques for measuring saturated hydraulic conductivity: Water Resources Research, v. 27, no. 6, p. 1263-1269, https://doi.org/10.1029/91WR00367.","productDescription":"7 p. ","startPage":"1263","endPage":"1269","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338090,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"27","issue":"6","noUsgsAuthors":false,"publicationDate":"2008-01-08","publicationStatus":"PW","scienceBaseUri":"58d38d61e4b0236b68f98f7a","contributors":{"authors":[{"text":"Nimmo, John R. 0000-0001-8191-1727 jrnimmo@usgs.gov","orcid":"https://orcid.org/0000-0001-8191-1727","contributorId":757,"corporation":false,"usgs":true,"family":"Nimmo","given":"John","email":"jrnimmo@usgs.gov","middleInitial":"R.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true}],"preferred":true,"id":685732,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mello, Karen A.","contributorId":189694,"corporation":false,"usgs":false,"family":"Mello","given":"Karen","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":685733,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70185802,"text":"70185802 - 1991 - Agricultural research to improve water quality","interactions":[],"lastModifiedDate":"2019-03-28T11:00:41","indexId":"70185802","displayToPublicDate":"1991-06-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2456,"text":"Journal of Soil and Water Conservation","active":true,"publicationSubtype":{"id":10}},"title":"Agricultural research to improve water quality","docAbstract":"ime courses for ingest~on, retention and release via feces of microbial food was investigated
using 2 b~valves w~th d~fferent feeding strategies, Potamocorbula amurensis and Macoma
balthica. The results showed 2 pathways for the uptake of food material in these clams. The first is
represented by an initlal label pulse in the feces. The second pathway operates over longer time
periods. Inert \"Cr-labeled beads were used to determine time frames for these pathways. The first
pathway, involving extracellular digestion and intestinal uptake, is relatively inefficient In the
digestion of bacter~al cells by P amurensis but more efficient in M. balthica. The second pathway,
involving intracellular digestion withln the digestive gland of both clams, was highly efficient in
absorb~ng bacterial carbon, and was responsible for most chromium uptake. Differences in the overall
retention of microbial \"Cr and I4C relate not to gut-passage times but to the processing and release
strategies of the food material by these 2 clams.
Short-term instability in the behaviour of a small, meandering alluvial channel is identified from the relation between sinuosity and either floodplain slope or channel slope within 17 reaches along an 81-kilometre section of the Belle Fourche River in western South Dakota. In reaches 1 to 4 and 11 to 17 the channel is relatively stable and sinuosity varies inversely with channel slope. In reaches 5 to 10, sinuosity is positively related to floodplain slope. Sinuosity increases markedly in reaches 5, 6, and 7 (which are immediately downstream from a discontinuity in the long profile of the floodplain) in association with an increase in floodplain slope. Immediately upstream from the discontinuity, bankfull channel depth and sinuosity decrease and the area of the floodplain reworked by meander migration between 1939 and 1981 increases, in association with a decrease in floodplain slope. Channel behaviour in reaches 5 to 10 is best explained as a consequence of neotectonic activity, as indicated by changes in elevation recorded along geodetic survey lines that cross lineaments that may delimit the eastern boundary of the Black Hills uplift. Sinuosity acts as a barometer of the effects of neotectonic activity on alluvial channels. Initial indications of channel and floodplain instability due to neotectonic activity may be derived from evidence of anomalously active channel migration, as documented from photographic or topographic sources.
","language":"English","publisher":"Wiley","doi":"10.1002/esp.3290160304","usgsCitation":"Gomez, B., and Marron, D.C., 1991, Neotectonic effects on sinuosity and channel migration, Belle Fourche River, Western South Dakota: Earth Surface Processes and Landforms, v. 16, no. 3, p. 227-235, https://doi.org/10.1002/esp.3290160304.","productDescription":"8 p. ","startPage":"227","endPage":"235","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338084,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"South Dakota","otherGeospatial":"Belle Fourche River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -103.34564208984375,\n 44.620287898534244\n ],\n [\n -103.32298278808594,\n 44.61637785698343\n ],\n [\n -103.21517944335938,\n 44.5435052132082\n ],\n [\n -103.11012268066405,\n 44.4190688110522\n ],\n [\n -103.02978515625,\n 44.38865427337759\n ],\n [\n -103.01193237304688,\n 44.422011314236634\n ],\n [\n -103.05587768554686,\n 44.476910857223224\n ],\n [\n -103.15887451171875,\n 44.61784415342067\n ],\n [\n -103.260498046875,\n 44.65839700490685\n ],\n [\n -103.37860107421875,\n 44.66865287227321\n ],\n [\n -103.52073669433594,\n 44.68476556953855\n ],\n [\n -103.623046875,\n 44.681348099056066\n ],\n [\n -103.71231079101562,\n 44.687694669498015\n ],\n [\n -103.78578186035156,\n 44.70868221820806\n ],\n [\n -103.79814147949219,\n 44.69111176558736\n ],\n [\n -103.77342224121092,\n 44.66767620116954\n ],\n [\n -103.70750427246094,\n 44.64423115768092\n ],\n [\n -103.63334655761719,\n 44.63445959194018\n ],\n [\n -103.34564208984375,\n 44.620287898534244\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"16","issue":"3","noUsgsAuthors":false,"publicationDate":"2006-07-25","publicationStatus":"PW","scienceBaseUri":"58d38d61e4b0236b68f98f80","contributors":{"authors":[{"text":"Gomez, Basil","contributorId":65475,"corporation":false,"usgs":true,"family":"Gomez","given":"Basil","email":"","affiliations":[],"preferred":false,"id":685715,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Marron, Donna C.","contributorId":6900,"corporation":false,"usgs":true,"family":"Marron","given":"Donna","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":685716,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70185800,"text":"70185800 - 1991 - Extent of reaction in open systems with multiple heterogeneous reactions","interactions":[],"lastModifiedDate":"2017-03-29T10:37:11","indexId":"70185800","displayToPublicDate":"1991-05-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":5349,"text":"American Institute of Chemical Engineers ","active":true,"publicationSubtype":{"id":10}},"title":"Extent of reaction in open systems with multiple heterogeneous reactions","docAbstract":"The familiar batch concept of extent of reaction is reexamined for systems of reactions occurring in open systems. Because species concentrations change as a result of transport processes as well as reactions in open systems, the extent of reaction has been less useful in practice in these applications. It is shown that by defining the extent of the equivalent batch reaction and a second contribution to the extent of reaction due to the transport processes, it is possible to treat the description of the dynamics of flow through porous media accompanied by many chemical reactions in a uniform, concise manner. This approach tends to isolate the reaction terms among themselves and away from the model partial differential equations, thereby enabling treatment of large problems involving both equilibrium and kinetically controlled reactions. Implications on the number of coupled partial differential equations necessary to be solved and on numerical algorithms for solving such problems are discussed. Examples provided illustrate the theory applied to solute transport in groundwater flow.
A large-scale natural gradient tracer test was conducted to examine the transport of reactive and nonreactive tracers in a sand and gravel aquifer on Cape Cod, Massachusetts. As part of this test the transport of bromide, a nonreactive tracer, was monitored for about 280 m and quantified using spatial moments. The calculated mass of bromide for each sampling date varied between 85% and 105% of the injected mass using an estimated porosity of 0.39, and the center of mass moved at a nearly constant horizontal velocity of 0.42 m per day. A nonlinear change in the bromide longitudinal variance was observed during the first 26 m of travel distance, but afterward the variance followed a linear trend, indicating the longitudinal dispersivity had reached a constant value of 0.96 m. The transverse dispersivities were much smaller; transverse horizontal dispersivity was 1.8 cm, and transverse vertical dispersivity was about 1.5 mm.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/91WR00242","usgsCitation":"Garabedian, S.P., LeBlanc, D.R., Gelhar, L.W., and Celia, M.A., 1991, Large-scale natural gradient tracer test in sand and gravel, Cape Cod, Massachusetts: 2. Analysis of spatial moments for a nonreactive tracer: Water Resources Research, v. 27, no. 5, p. 911-924, https://doi.org/10.1029/91WR00242.","productDescription":"14 p. ","startPage":"911","endPage":"924","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338083,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Massachusetts","otherGeospatial":"Cape Cod ","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -70.57273864746094,\n 41.6010669423553\n ],\n [\n -70.44708251953125,\n 41.6010669423553\n ],\n [\n -70.44708251953125,\n 41.697013213237994\n ],\n [\n -70.57273864746094,\n 41.697013213237994\n ],\n [\n -70.57273864746094,\n 41.6010669423553\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"27","issue":"5","noUsgsAuthors":false,"publicationDate":"2008-01-08","publicationStatus":"PW","scienceBaseUri":"58d38d61e4b0236b68f98f82","contributors":{"authors":[{"text":"Garabedian, Stephen P.","contributorId":91090,"corporation":false,"usgs":true,"family":"Garabedian","given":"Stephen","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":685711,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"LeBlanc, Dennis R.","contributorId":189689,"corporation":false,"usgs":false,"family":"LeBlanc","given":"Dennis","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":685712,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gelhar, Lynn W.","contributorId":189690,"corporation":false,"usgs":false,"family":"Gelhar","given":"Lynn","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":685713,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Celia, Michael A.","contributorId":189683,"corporation":false,"usgs":false,"family":"Celia","given":"Michael","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":685714,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70185490,"text":"70185490 - 1991 - Sampling design for groundwater solute transport: Tests of methods and analysis of Cape Cod tracer test data","interactions":[],"lastModifiedDate":"2018-02-27T11:36:12","indexId":"70185490","displayToPublicDate":"1991-05-01T00:00:00","publicationYear":"1991","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":"Sampling design for groundwater solute transport: Tests of methods and analysis of Cape Cod tracer test data","docAbstract":"Tests of a one-dimensional sampling design methodology on measurements of bromide concentration collected during the natural gradient tracer test conducted by the U.S. Geological Survey on Cape Cod, Massachusetts, demonstrate its efficacy for field studies of solute transport in groundwater and the utility of one-dimensional analysis. The methodology was applied to design of sparse two-dimensional networks of fully screened wells typical of those often used in engineering practice. In one-dimensional analysis, designs consist of the downstream distances to rows of wells oriented perpendicular to the groundwater flow direction and the timing of sampling to be carried out on each row. The power of a sampling design is measured by its effectiveness in simultaneously meeting objectives of model discrimination, parameter estimation, and cost minimization. One-dimensional models of solute transport, differing in processes affecting the solute and assumptions about the structure of the flow field, were considered for description of tracer cloud migration. When fitting each model using nonlinear regression, additive and multiplicative error forms were allowed for the residuals which consist of both random and model errors. The one-dimensional single-layer model of a nonreactive solute with multiplicative error was judged to be the best of those tested. Results show the efficacy of the methodology in designing sparse but powerful sampling networks. Designs that sample five rows of wells at five or fewer times in any given row performed as well for model discrimination as the full set of samples taken up to eight times in a given row from as many as 89 rows. Also, designs for parameter estimation judged to be good by the methodology were as effective in reducing the variance of parameter estimates as arbitrary designs with many more samples. Results further showed that estimates of velocity and longitudinal dispersivity in one-dimensional models based on data from only five rows of fully screened wells each sampled five or fewer times were practically equivalent to values determined from moments analysis of the complete three-dimensional set of 29,285 samples taken during 16 sampling times.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/90WR02657","usgsCitation":"Knopman, D.S., Voss, C.I., and Garabedian, S.P., 1991, Sampling design for groundwater solute transport: Tests of methods and analysis of Cape Cod tracer test data: Water Resources Research, v. 27, no. 5, p. 925-949, https://doi.org/10.1029/90WR02657.","productDescription":"25 p. ","startPage":"925","endPage":"949","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338085,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"27","issue":"5","noUsgsAuthors":false,"publicationDate":"2008-01-08","publicationStatus":"PW","scienceBaseUri":"58d38d61e4b0236b68f98f7e","contributors":{"authors":[{"text":"Knopman, Debra S.","contributorId":51472,"corporation":false,"usgs":true,"family":"Knopman","given":"Debra","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":685719,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Voss, Clifford I. 0000-0001-5923-2752 cvoss@usgs.gov","orcid":"https://orcid.org/0000-0001-5923-2752","contributorId":1559,"corporation":false,"usgs":true,"family":"Voss","given":"Clifford","email":"cvoss@usgs.gov","middleInitial":"I.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":685720,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Garabedian, Stephen P.","contributorId":91090,"corporation":false,"usgs":true,"family":"Garabedian","given":"Stephen","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":685721,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70185491,"text":"70185491 - 1991 - Large-scale natural gradient tracer test in sand and gravel, Cape Cod, Massachusetts: 1. Experimental design and observed tracer movement","interactions":[],"lastModifiedDate":"2018-02-27T11:58:34","indexId":"70185491","displayToPublicDate":"1991-05-01T00:00:00","publicationYear":"1991","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":"Large-scale natural gradient tracer test in sand and gravel, Cape Cod, Massachusetts: 1. Experimental design and observed tracer movement","docAbstract":"A large-scale natural gradient tracer experiment was conducted on Cape Cod, Massachusetts, to examine the transport and dispersion of solutes in a sand and gravel aquifer. The nonreactive tracer, bromide, and the reactive tracers, lithium and molybdate, were injected as a pulse in July 1985 and monitored in three dimensions as they moved as far as 280 m down-gradient through an array of multilevel samplers. The bromide cloud moved horizontally at a rate of 0.42 m per day. It also moved downward about 4 m because of density-induced sinking early in the test and accretion of areal recharge from precipitation. After 200 m of transport, the bromide cloud had spread more than 80 m in the direction of flow, but was only 14 m wide and 4–6 m thick. The lithium and molybdate clouds followed the same path as the bromide cloud, but their rates of movement were retarded about 50% relative to bromide movement because of sorption onto the sediments.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/91WR00241","usgsCitation":"LeBlanc, D.R., Garabedian, S.P., Hess, K.M., Gelhar, L.W., Quadri, R.D., Stollenwerk, K.G., and Wood, W., 1991, Large-scale natural gradient tracer test in sand and gravel, Cape Cod, Massachusetts: 1. Experimental design and observed tracer movement: Water Resources Research, v. 27, no. 5, p. 895-910, https://doi.org/10.1029/91WR00241.","productDescription":"16 p. ","startPage":"895","endPage":"910","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338087,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Massachusetts","otherGeospatial":"Cape Cod","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -70.58303833007812,\n 41.60774162535756\n ],\n [\n -70.46905517578125,\n 41.60774162535756\n ],\n [\n -70.46905517578125,\n 41.703165313736655\n ],\n [\n -70.58303833007812,\n 41.703165313736655\n ],\n [\n -70.58303833007812,\n 41.60774162535756\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"27","issue":"5","noUsgsAuthors":false,"publicationDate":"2008-01-08","publicationStatus":"PW","scienceBaseUri":"58d38d61e4b0236b68f98f7c","contributors":{"authors":[{"text":"LeBlanc, Denis R. 0000-0002-4646-2628 dleblanc@usgs.gov","orcid":"https://orcid.org/0000-0002-4646-2628","contributorId":1696,"corporation":false,"usgs":true,"family":"LeBlanc","given":"Denis","email":"dleblanc@usgs.gov","middleInitial":"R.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":true,"id":685722,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Garabedian, Stephen P.","contributorId":91090,"corporation":false,"usgs":true,"family":"Garabedian","given":"Stephen","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":685723,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hess, Kathryn M.","contributorId":49012,"corporation":false,"usgs":true,"family":"Hess","given":"Kathryn","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":685724,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Gelhar, Lynn W.","contributorId":189690,"corporation":false,"usgs":false,"family":"Gelhar","given":"Lynn","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":685725,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Quadri, Richard D.","contributorId":189692,"corporation":false,"usgs":false,"family":"Quadri","given":"Richard","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":685726,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Stollenwerk, Kenneth G. kgstolle@usgs.gov","contributorId":578,"corporation":false,"usgs":true,"family":"Stollenwerk","given":"Kenneth","email":"kgstolle@usgs.gov","middleInitial":"G.","affiliations":[],"preferred":true,"id":685727,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Wood, Warren W.","contributorId":47770,"corporation":false,"usgs":false,"family":"Wood","given":"Warren W.","affiliations":[{"id":6601,"text":"Michigan State University","active":true,"usgs":false}],"preferred":false,"id":685728,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70185493,"text":"70185493 - 1991 - Comment on the treatment of residual water content in “A consistent set of parametric models for the two-phase flow of immiscible fluids in the subsurface” by L. Luckner et al.","interactions":[],"lastModifiedDate":"2018-02-27T11:52:58","indexId":"70185493","displayToPublicDate":"1991-04-01T00:00:00","publicationYear":"1991","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":"Comment on the treatment of residual water content in “A consistent set of parametric models for the two-phase flow of immiscible fluids in the subsurface” by L. Luckner et al.","docAbstract":"Luckner et al. [1989] (hereinafter LVN) present a clear summary and generalization of popular formulations used for convenient representation of porous media fluid flow characteristics, including water content (θ) related to suction (h) and hydraulic conductivity (K) related to θ or h. One essential but problematic element in the LVN models is the concept of residual water content (θr; in LVN, θw,r). Most studies using θr determine its value as a fitted parameter and make the assumption that liquid flow processes are negligible at θ values less than θr. While the LVN paper contributes a valuable discussion of the nature of θr, it leaves several problems unresolved, including fundamental difficulties in associating a definite physical condition with θr, practical inadequacies of the models at low θ values, and difficulties in designating a main wetting curve.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/91WR00165","usgsCitation":"Nimmo, J.R., 1991, Comment on the treatment of residual water content in “A consistent set of parametric models for the two-phase flow of immiscible fluids in the subsurface” by L. Luckner et al.: Water Resources Research, v. 27, no. 4, p. 661-662, https://doi.org/10.1029/91WR00165.","productDescription":"2 p. ","startPage":"661","endPage":"662","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338089,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"27","issue":"4","noUsgsAuthors":false,"publicationDate":"2008-01-08","publicationStatus":"PW","scienceBaseUri":"58d38d61e4b0236b68f98f84","contributors":{"authors":[{"text":"Nimmo, John R. 0000-0001-8191-1727 jrnimmo@usgs.gov","orcid":"https://orcid.org/0000-0001-8191-1727","contributorId":757,"corporation":false,"usgs":true,"family":"Nimmo","given":"John","email":"jrnimmo@usgs.gov","middleInitial":"R.","affiliations":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":685731,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70171301,"text":"70171301 - 1991 - Hydrochemistry of the south coastal plain aquifer system of Puerto Rico and its relation to surface water recharge","interactions":[],"lastModifiedDate":"2016-06-02T09:32:31","indexId":"70171301","displayToPublicDate":"1991-03-06T06:30:00","publicationYear":"1991","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Hydrochemistry of the south coastal plain aquifer system of Puerto Rico and its relation to surface water recharge","largerWorkType":{"id":24,"text":"Conference Paper"},"largerWorkTitle":"International Symposium on Tropical Hydrology","largerWorkSubtype":{"id":19,"text":"Conference Paper"},"conferenceTitle":"International Symposium on Tropical Hydrology","conferenceDate":"July 1990","conferenceLocation":"San Juan, Puerto Rico","language":"English","publisher":"American Water Resources Association","publisherLocation":"Bethesda, MD","usgsCitation":"Gomez-Gomez, F., 1991, Hydrochemistry of the south coastal plain aquifer system of Puerto Rico and its relation to surface water recharge, in International Symposium on Tropical Hydrology, v. 15, San Juan, Puerto Rico, July 1990, p. 57-75.","productDescription":"19 p.","startPage":"57","endPage":"75","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":156,"text":"Caribbean Water Science Center","active":true,"usgs":true}],"links":[{"id":321751,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"15","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"57481e33e4b07e28b664dbc0","contributors":{"editors":[{"text":"Gomez-Gomez, Fernando","contributorId":169637,"corporation":false,"usgs":false,"family":"Gomez-Gomez","given":"Fernando","email":"","affiliations":[],"preferred":false,"id":631647,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"Quinones-Aponte, Vicente","contributorId":48552,"corporation":false,"usgs":true,"family":"Quinones-Aponte","given":"Vicente","email":"","affiliations":[],"preferred":false,"id":631648,"contributorType":{"id":2,"text":"Editors"},"rank":2},{"text":"Johnson, A.I.","contributorId":82676,"corporation":false,"usgs":true,"family":"Johnson","given":"A.I.","email":"","affiliations":[],"preferred":false,"id":631649,"contributorType":{"id":2,"text":"Editors"},"rank":3}],"authors":[{"text":"Gomez-Gomez, Fernando","contributorId":169637,"corporation":false,"usgs":false,"family":"Gomez-Gomez","given":"Fernando","email":"","affiliations":[],"preferred":false,"id":630495,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ]}