Approximately 2550 km of single-channel high-resolution seismic reflection profiles have been interpreted and calibrated with lithological and geochronological information from four representative piston cores and one grab sample to provide a regional stratigraphie framework for the subbottom deposits of Lake Ontario. Five units overlying Paleozoic bedrock were identified and mapped. These are classified as informal units and represent, from oldest to youngest: (A) subglacial till (?) deposited by the Port Huron ice at the end of the Wisconsin glaciation; (B) an ice-marginal (?) unit confined to the western part of the lake that was probably deposited during retreat of the Port Huron ice shortly after 13 ka; (C) a regionally extensive unit of laminated glacio-lacustrine clay that accumulated until about 11 ka; (D) a weakly laminated to more massive lake clay deposited during a period of reduced water supply and rising water levels after the drawdown of the high-level glacial lakes (Iroquois and successors); and (E) modern lake clay less than 10 m thick that began accumulating around 6-8 ka with the subsequent return of upper Great Lakes drainage through the Ontario basin. Seismic reflections also define the configuration of the bedrock surface and pre-glacial stream valleys incised in the bedrock surface. Several anomalous bottom and subbottom features in the surficial sediments are mapped, such as discontinuous and offset reflections, furrows, gas pockets, and areas of large subbottom relief. None of these features appear to be spatially correlative with the diffuse seismicity that characterizes the lake area or with deeper structures such as Paleozoic bedrock faults or crustal-penetrating faults in the Precambrian basement.
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Site-characterization activities supported by this model include characterizing the three-dimensional geometry of lithologic units and faults, and providing boundary conditions for geostatistical models and site-scale fluid flow modeling. This model supports the conceptual design as well as construction efforts for the proposed ramps of the ESF and potential high-level nuclear waste repository.
","largerWorkType":{"id":24,"text":"Conference Paper"},"largerWorkTitle":"FOCUS'93: Site Characterization and Model Validation","conferenceTitle":"FOCUS'93: Site Characterization and Model Validation","conferenceDate":"September 26-29, 1993","conferenceLocation":"Las Vegas, NV","language":"English","publisher":"American Nuclear Society","usgsCitation":"Buesch, D.C., Spengler, R., Nelson, J., and Dickerson, R., 1993, Three-dimensional lithostratigraphic model at Yucca Mountain, Nevada: A framework for fluid transport modeling and engineering design, in FOCUS'93: Site Characterization and Model Validation, Las Vegas, NV, September 26-29, 1993, p. 226-231.","productDescription":"6 p.","startPage":"226","endPage":"231","costCenters":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"links":[{"id":354848,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":354847,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://www.osti.gov/servlets/purl/145313"}],"country":"United States","state":"Nevada","otherGeospatial":"Yucca Mountain","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -116.69677734375,\n 36.12012758978146\n ],\n [\n -115.55419921875,\n 36.12012758978146\n ],\n [\n -115.55419921875,\n 37.00255267215955\n ],\n [\n -116.69677734375,\n 37.00255267215955\n ],\n [\n -116.69677734375,\n 36.12012758978146\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5c1119fde4b034bf6a81919c","contributors":{"authors":[{"text":"Buesch, David C. 0000-0002-4978-5027 dbuesch@usgs.gov","orcid":"https://orcid.org/0000-0002-4978-5027","contributorId":1154,"corporation":false,"usgs":true,"family":"Buesch","given":"David","email":"dbuesch@usgs.gov","middleInitial":"C.","affiliations":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true},{"id":309,"text":"Geology and Geophysics Science Center","active":true,"usgs":true},{"id":234,"text":"Earthquake Hazards Program","active":true,"usgs":true}],"preferred":true,"id":737495,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Spengler, R.W.","contributorId":7281,"corporation":false,"usgs":true,"family":"Spengler","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":737496,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Nelson, J.E.","contributorId":50306,"corporation":false,"usgs":true,"family":"Nelson","given":"J.E.","email":"","affiliations":[],"preferred":false,"id":737497,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Dickerson, R. P.","contributorId":23968,"corporation":false,"usgs":true,"family":"Dickerson","given":"R. P.","affiliations":[],"preferred":false,"id":737498,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70199876,"text":"70199876 - 1993 - Transport and natural attenuation of Cu, Zn, As, and Fe in the acid mine drainage of Leviathan and Bryant Creeks","interactions":[],"lastModifiedDate":"2018-10-02T09:43:46","indexId":"70199876","displayToPublicDate":"1993-12-20T09:43:11","publicationYear":"1993","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Transport and natural attenuation of Cu, Zn, As, and Fe in the acid mine drainage of Leviathan and Bryant Creeks","docAbstract":"The Leviathan and Bryant Creek (LBC) drainage system, on the border of California and Nevada, flows through overburden and waste from a former open-pit sulfur mine. The drainage contains acid mine waters with high concentrations of several trace elements, including Cu, Zn, and As, derived from oxidative weathering of sulfides in the wastes and altered bedrock. In June and October, 1982, the mainstream and tributary flows of the LBC drainage were measured and the waters sampled and analyzed for major and trace elements. Empirical mass flow and metal attenuation rates were determined, and chemical models were used to examine mechanisms of trace element removal during downstream transport. In June the flow in the mainstream was 2-5 times greater than in October, and with higher contributions from the acid mine effluent. Seasonal variations in the attenuation rates of Cu, Zn, and As were directly related to this increase in acid mine-effluent production, and to the consequent increase in the acidity of the mainstream drainage. Although As concentrations immediately below the mine site were high in June, As was readily removed from solution by adsorption onto an assumed iron(III) oxyhydroxysulfate precipitate, whereas Cu was incompletely adsorbed and Zn remained unaffected by adsorption. In October, the smaller discharge of acidic LBC drainage waters were more readily diluted (and neutralized) by other regional tributaries. Arsenic concentrations remained low, and both Cu and Zn were removed from solution by adsorption onto iron(III) oxyhydroxysulfate in the lower regions of the LBC drainage system.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Environmental geochemistry of sulfide oxidation","largerWorkSubtype":{"id":12,"text":"Conference publication"},"language":"English","publisher":"American Chemical Society","doi":"10.1021/bk-1994-0550.ch017","isbn":"9780841227729","usgsCitation":"Webster, J.G., Nordstrom, D.K., and Smith, K.S., 1993, Transport and natural attenuation of Cu, Zn, As, and Fe in the acid mine drainage of Leviathan and Bryant Creeks, chap. of Environmental geochemistry of sulfide oxidation, v. 550, p. 244-260, https://doi.org/10.1021/bk-1994-0550.ch017.","productDescription":"17 p.","startPage":"244","endPage":"260","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":358007,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California, Nevada","otherGeospatial":"Leviathan Creek, Bryant Creek","volume":"550","noUsgsAuthors":false,"publicationDate":"2009-07-23","publicationStatus":"PW","scienceBaseUri":"5c111a1ce4b034bf6a8194db","contributors":{"authors":[{"text":"Webster, Jenny G.","contributorId":208417,"corporation":false,"usgs":false,"family":"Webster","given":"Jenny","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":747093,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Nordstrom, D. Kirk 0000-0003-3283-5136 dkn@usgs.gov","orcid":"https://orcid.org/0000-0003-3283-5136","contributorId":749,"corporation":false,"usgs":true,"family":"Nordstrom","given":"D.","email":"dkn@usgs.gov","middleInitial":"Kirk","affiliations":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":false,"id":747094,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Smith, Kathleen S. 0000-0001-8547-9804 ksmith@usgs.gov","orcid":"https://orcid.org/0000-0001-8547-9804","contributorId":182,"corporation":false,"usgs":true,"family":"Smith","given":"Kathleen","email":"ksmith@usgs.gov","middleInitial":"S.","affiliations":[{"id":211,"text":"Crustal Geophysics and Geochemistry Science Center","active":true,"usgs":true}],"preferred":true,"id":747095,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70186724,"text":"70186724 - 1993 - Formation of left-lateral fractures within the Summit Ridge Shear Zone, 1989 Loma Prieta, California, Earthquake","interactions":[],"lastModifiedDate":"2017-04-07T14:21:50","indexId":"70186724","displayToPublicDate":"1993-12-10T00:00:00","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Formation of left-lateral fractures within the Summit Ridge Shear Zone, 1989 Loma Prieta, California, Earthquake","docAbstract":"The 1989 Loma Prieta, California, earthquake is characterized by the lack of major, throughgoing, coseismic, right-lateral faulting along strands of the San Andreas fault zone in the epicentral area. Instead, throughout the Summit Ridge area there are zones of tension cracks and left-lateral fracture zones oriented about N45°W, that is, roughly parallel to the San Andreas fault in this area. The left-lateral fractures zones are enigmatic because their left-lateral slip is opposite to the right-lateral sense of the relative motion between the Pacific and North American plates. We suggest that the enigmatic fractures can be understood if we assume that coseismic deformation was by right-lateral shear across a broad zone, about 0.5 km wide and 4 km long, beneath Summit Ridge. The shear zone has an orientation of about N70° W and is oblique to the San Andreas fault zone, which has a trend of N45° to 50°W, so that right-lateral shearing, along with some dilation, can account for the orientation of the fracture zones. Using an analog, kinematic model of the Summit Ridge shear zone and the observable geometric parameters (a shear zone about 0.5 km wide, an acute angle of 25° between the tension cracks and the shear-zone walls, left-lateral slip of 5 cm, and spacing of about 100 m in the tension cracks) we estimate that the amount of right-lateral shift across the Summit Ridge shear zone was on the order of 1.4 m. This is comparable to the amount of slip for coseismic faulting at depth, 1.9 to 2.4 m, as computed by several investigators. Thus contrary to most previous reports on the Loma Prieta earthquake, which assert that coseismic, right-lateral ground rupture was restricted to considerable (greater than 4 km) depths in the epicentral area, we find that nearly all the right-lateral offset is represented at the ground surface by the Summit Ridge shear zone.
","language":"English","publisher":"Wiley","doi":"10.1029/93JB02385","usgsCitation":"Johnson, A.M., and Fleming, R.W., 1993, Formation of left-lateral fractures within the Summit Ridge Shear Zone, 1989 Loma Prieta, California, Earthquake: Journal of Geophysical Research B: Solid Earth, v. 98, no. B12, p. 21823-21837, https://doi.org/10.1029/93JB02385.","productDescription":"15 p. ","startPage":"21823","endPage":"21837","costCenters":[],"links":[{"id":339452,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"98","issue":"B12","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"58e8a54ae4b09da6799d63e7","contributors":{"authors":[{"text":"Johnson, Arvid M.","contributorId":99547,"corporation":false,"usgs":true,"family":"Johnson","given":"Arvid","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":690366,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fleming, Robert W.","contributorId":102062,"corporation":false,"usgs":true,"family":"Fleming","given":"Robert","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":690367,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70186657,"text":"70186657 - 1993 - Importance of model parameterization in finite fault inversions: Application to the 1974 Mw 8.0 Peru Earthquake","interactions":[],"lastModifiedDate":"2017-04-06T14:22:38","indexId":"70186657","displayToPublicDate":"1993-12-10T00:00:00","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Importance of model parameterization in finite fault inversions: Application to the 1974 Mw 8.0 Peru Earthquake","docAbstract":"The spatial and temporal slip distributions for the October 3, 1974 (Mw = 8.0), Peru subduction zone earthquake and its largest aftershock on November 9 (Ms = 7.1) are calculated and analyzed in terms of the inversion parameterization and tectonic significance. Teleseismic, long-period World-Wide Standard Seismograph Network, P and SH waveforms are inverted to obtain the rupture histories. We demonstrate that erroneous results are obtained if a parameterization is used that does not allow for a sufficiently complex source, involving spatial variation in slip amplitude, risetime, and rupture time. The inversion method utilizes a parameterization of the fault that allows for a discretized source risetime and rupture time. Well-located aftershocks recorded on a local network have the same general pattern as teleseismically determined hypocenters and help to constrain the geometry of the subduction zone. For the main shock a hinged fault is preferred having a shallow plane with a dip of 11° and a deeper, landward plane with a dip of 30°. The preferred nucleation depth lies between 11 and 15 km. A bilateral rupture is obtained with two major concentrations of slip, one 60 to 70 km to the northwest of the epicenter and a second 80 to 100 km to the south and southeast of the epicenter. For these source regions, risetimes vary from 6 to 18 s. Our estimates of risetimes are consistent with the time for the rupture to traverse the dominant local asperity. The slip distribution for the November 9 aftershock falls within a conspicuous hole in the main shock rupture pattern, near the hypocenter of the main shock. The November 9 event has a simple risetime function with a duration of 2 s. Aftershocks recorded by the local network are shown to cluster near the hypocenter of the impending November 9 event and downdip from the largest main shock source region. Slip during the main shock is concentrated at shallow depths above 15 km and extends updip from the hypocenter to near the plate boundary at the trench axis. The large amount of slip at shallow depths is attributed to the absence of any significant accretionary wedge of sediments, and the relatively young age and high convergence rate of the subducted plate, which results in good seismic coupling near the trench axis.
","language":"English","publisher":"Wiley","doi":"10.1029/93JB02453","usgsCitation":"Hartzell, S.H., and Langer, C., 1993, Importance of model parameterization in finite fault inversions: Application to the 1974 Mw 8.0 Peru Earthquake: Journal of Geophysical Research B: Solid Earth, v. 98, no. B12, p. 22123-22134, https://doi.org/10.1029/93JB02453.","productDescription":"12 p. ","startPage":"22123","endPage":"22134","costCenters":[],"links":[{"id":479420,"rank":0,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/93jb02453","text":"Publisher Index Page"},{"id":339357,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"98","issue":"B12","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"58e75407e4b09da6799c0c8a","contributors":{"authors":[{"text":"Hartzell, Stephen H. 0000-0003-0858-9043 shartzell@usgs.gov","orcid":"https://orcid.org/0000-0003-0858-9043","contributorId":2594,"corporation":false,"usgs":true,"family":"Hartzell","given":"Stephen","email":"shartzell@usgs.gov","middleInitial":"H.","affiliations":[{"id":300,"text":"Geologic Hazards Science Center","active":true,"usgs":true}],"preferred":true,"id":690180,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Langer, Charley","contributorId":190646,"corporation":false,"usgs":false,"family":"Langer","given":"Charley","email":"","affiliations":[],"preferred":false,"id":690181,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70207075,"text":"70207075 - 1993 - Deformation from 1973 through 1991 in the epicentral area of the 1992 Landers, California, Earthquake (Ms = 7.5)","interactions":[],"lastModifiedDate":"2020-05-28T13:52:07.17653","indexId":"70207075","displayToPublicDate":"1993-12-05T12:39:07","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Deformation from 1973 through 1991 in the epicentral area of the 1992 Landers, California, Earthquake (Ms = 7.5)","docAbstract":"Deformation of a 50 × 60 km trilateration network that spans the epicenter of the 1992 Landers earthquake(Ms = 7.5) was measured by seven surveys over the 19 years preceding the earthquake. Three moderate earthquakes (1979 Homestead Valley, Ms = 5.6; 1986 North Palm Springs, Ms = 6.0; and 1992 Joshua Tree, Ms = 6.1) occurred within the network during those 19 years. Here we use geodetic and seismic data to construct a dislocation model for each of the three moderate earthquakes. Coseismic changes due to these three moderate earthquakes as predicted by the dislocation models are then removed from the trilateration data. The residual geodetic changes appear to be uniform in time. We take those changes to represent secular strain accumulation. This strain accumulation clearly shows right‐lateral shear across the San Andreas fault but also suggests a northwest‐southeast extension northeast of the eastern end of the “Big Bend” of the San Andreas fault. The Landers earthquake ruptured along a north‐northwest trend across this region of northwest‐southeast extension.
No abstract available.
","language":"English","publisher":"National Park Service","usgsCitation":"Hostetler, S.W., and Varley, J., 1993, Modeling the effects of climate change on the thermal structure of Yellowstone Lake: Park Science, v. 13, no. 1.","productDescription":"1 p.","startPage":"16","costCenters":[{"id":481,"text":"Northern Rocky Mountain Science Center","active":true,"usgs":true}],"links":[{"id":380860,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":380859,"rank":1,"type":{"id":11,"text":"Document"},"url":"https://irma.nps.gov/DataStore/DownloadFile/615001"}],"country":"United States","state":"Wyoming","otherGeospatial":"Yellowstone Lake","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -110.819091796875,\n 44.22748846630169\n ],\n [\n -110.03631591796875,\n 44.22748846630169\n ],\n [\n -110.03631591796875,\n 44.63934558051711\n ],\n [\n -110.819091796875,\n 44.63934558051711\n ],\n [\n -110.819091796875,\n 44.22748846630169\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"13","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Hostetler, Steven W. 0000-0003-2272-8302 swhostet@usgs.gov","orcid":"https://orcid.org/0000-0003-2272-8302","contributorId":3249,"corporation":false,"usgs":true,"family":"Hostetler","given":"Steven","email":"swhostet@usgs.gov","middleInitial":"W.","affiliations":[{"id":200,"text":"Coop Res Unit Seattle","active":true,"usgs":true},{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":805861,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Varley, John","contributorId":245304,"corporation":false,"usgs":false,"family":"Varley","given":"John","email":"","affiliations":[],"preferred":false,"id":805862,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70185445,"text":"70185445 - 1993 - Chlorofluorocarbons (CCl3F and CCl2F2) as dating tools and hydrologic tracers in shallow groundwater of the Delmarva Peninsula, Atlantic Coastal Plain, United States","interactions":[],"lastModifiedDate":"2018-03-21T15:25:58","indexId":"70185445","displayToPublicDate":"1993-12-01T00:00:00","publicationYear":"1993","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}},"displayTitle":"Chlorofluorocarbons (CCl3F and CCl2F2) as dating tools and hydrologic tracers in shallow groundwater of the Delmarva Peninsula, Atlantic Coastal Plain, United States","title":"Chlorofluorocarbons (CCl3F and CCl2F2) as dating tools and hydrologic tracers in shallow groundwater of the Delmarva Peninsula, Atlantic Coastal Plain, United States","docAbstract":"Concentrations of the Chlorofluorocarbons (CFCs) CFC-11 and CFC-12 were determined in groundwater from coastal plain sediments of the Delmarva Peninsula. CFC-modeled ages were calculated independently for CFC-11 and CFC-12, and agreed to within 2–3 years in the majority of the waters. Recharge temperatures, determined from dissolved nitrogen and argon concentrations, varied from 9±2°C over most of the peninsula to 14±2°C at the southernmost tip of the peninsula in Virginia. The CFC-modeled ages were examined in relation to the known hydrogeologic environment, both on regional scales and in more intensively sampled local scale networks. The CFC-modeled recharge years and measured tritium concentrations were used to reconstruct a tritium input function that was compared to the modeled tritium plus 3He distribution. Most of the present distribution of tritium in Delmarva groundwater is consistent with low dispersivities. The results of the study strongly support the use of CFCs for dating shallow, aerobic groundwater.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/93WR02073","usgsCitation":"Dunkle, S., Plummer, N., Busenberg, E., Phillips, P.J., Denver, J.M., Hamilton, P.A., Michel, R.L., and Coplen, T., 1993, Chlorofluorocarbons (CCl3F and CCl2F2) as dating tools and hydrologic tracers in shallow groundwater of the Delmarva Peninsula, Atlantic Coastal Plain, United States: Water Resources Research, v. 29, no. 12, p. 3837-3860, https://doi.org/10.1029/93WR02073.","productDescription":"24 p. ","startPage":"3837","endPage":"3860","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338035,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Delaware, Maryland ","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -75.7781982421875,\n 39.70718665682654\n ],\n [\n -76.0638427734375,\n 39.7240885773337\n ],\n [\n -76.3165283203125,\n 39.20671884491848\n ],\n [\n -76.4483642578125,\n 38.805470223177466\n ],\n [\n -76.2615966796875,\n 38.16911413556086\n ],\n [\n -76.025390625,\n 37.05079312980657\n ],\n [\n -75.43212890625,\n 37.13404537126446\n ],\n [\n -75.0091552734375,\n 38.58252615935333\n ],\n [\n -75.11352539062499,\n 38.91240739487225\n ],\n [\n -75.552978515625,\n 39.52946653645165\n ],\n [\n -75.4705810546875,\n 39.70718665682654\n ],\n [\n -75.4156494140625,\n 39.812755695478124\n ],\n [\n -75.574951171875,\n 39.842286020743394\n ],\n [\n -75.6683349609375,\n 39.825413103424786\n ],\n [\n -75.772705078125,\n 39.740986355883564\n ],\n [\n -75.7781982421875,\n 39.70718665682654\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"29","issue":"12","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"58d38d3ce4b0236b68f98ef4","contributors":{"authors":[{"text":"Dunkle, S.A.","contributorId":11248,"corporation":false,"usgs":true,"family":"Dunkle","given":"S.A.","email":"","affiliations":[],"preferred":false,"id":685595,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Plummer, Niel 0000-0002-4020-1013 nplummer@usgs.gov","orcid":"https://orcid.org/0000-0002-4020-1013","contributorId":190100,"corporation":false,"usgs":true,"family":"Plummer","given":"Niel","email":"nplummer@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":685596,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Busenberg, E.","contributorId":56796,"corporation":false,"usgs":true,"family":"Busenberg","given":"E.","affiliations":[],"preferred":false,"id":685597,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Phillips, P. J.","contributorId":31728,"corporation":false,"usgs":true,"family":"Phillips","given":"P.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":685598,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Denver, J. M.","contributorId":100356,"corporation":false,"usgs":true,"family":"Denver","given":"J.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":685599,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Hamilton, P. A.","contributorId":7247,"corporation":false,"usgs":true,"family":"Hamilton","given":"P.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":685600,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Michel, R. L.","contributorId":86375,"corporation":false,"usgs":true,"family":"Michel","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":685601,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Coplen, T.B.","contributorId":34147,"corporation":false,"usgs":true,"family":"Coplen","given":"T.B.","affiliations":[],"preferred":false,"id":685602,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}} ,{"id":70185443,"text":"70185443 - 1993 - Adaptive estimation of the log fluctuating conductivity from tracer data at the Cape Cod Site","interactions":[],"lastModifiedDate":"2020-01-07T15:41:22","indexId":"70185443","displayToPublicDate":"1993-12-01T00:00:00","publicationYear":"1993","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":"Adaptive estimation of the log fluctuating conductivity from tracer data at the Cape Cod Site","docAbstract":"An adaptive estimation scheme is used to obtain the integral scale and variance of the log-fluctuating conductivity at the Cape Cod site based on the fast Fourier transform/stochastic model of Deng et al. (1993) and a Kalmanlike filter. The filter incorporates prior estimates of the unknown parameters with tracer moment data to adaptively obtain improved estimates as the tracer evolves. The results show that significant improvement in the prior estimates of the conductivity can lead to substantial improvement in the ability to predict plume movement. The structure of the covariance function of the log-fluctuating conductivity can be identified from the robustness of the estimation. Both the longitudinal and transverse spatial moment data are important to the estimation.
Numerical simulation was used to study steady liquid water movement in a 5-m by 5-m vertical section containing a hypothetical fracture network under conditions of variable saturation. The fracture network was assumed to be embedded within an impermeable rock matrix. Three variations of a network were considered. The “mixed” network consisted of two fracture sets, a subvertical set containing five 125 μm average aperture fractures and a subhorizontal set containing four 25 μm average aperture fractures. The other two networks had identical fracture orientation and contained either all 125 μm or all 25 μm average aperture fractures. The TOUGH simulator was used to calculate the total steady liquid water flux through the network, the flux through individual fracture segments, and the pressure head at each fracture segment. A unit hydraulic gradient was imposed on the network by applying fixed pressure head boundaries (ranging from −0.25 to 0.0 m of water) of equal value to the top and bottom. Saturation and permeability versus pressure head relations for the two sets of fractures were determined with the VSFRAC model, which assumed that aperture was variable within an individual fracture. Results showed that the spatial distributions of pressure head and flux within the network, as well as the location of the dominant pathways, depended strongly on the prescribed boundary pressure head. For the mixed network, both pressure head and flux tended to become more spatially uniform when the boundary pressure head approached the pressure head at which the permeability thickness products of the large- and small-aperture fractures are equal (the crossover pressure head). These results imply that for systems similar to the one considered here, interpretation of actual measurements of pressure head and flux may be quite complex, and that representation of variably saturated fracture networks as an equivalent continuum may be more valid for some ranges in pressure head than for others. Equivalent permeability as a function of pressure head was calculated for the fracture network, illustrating how information collected on individual fractures may be used to estimate the flow properties of rock at larger scales.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/93WR02348","usgsCitation":"Kwicklis, E.M., and Healy, R.W., 1993, Numerical investigation of steady liquid water flow in a variably saturated fracture network: Water Resources Research, v. 29, no. 12, p. 4091-4102, https://doi.org/10.1029/93WR02348.","productDescription":"12 p. ","startPage":"4091","endPage":"4102","costCenters":[],"links":[{"id":339717,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"29","issue":"12","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"58f08e64e4b06911a29fa874","contributors":{"authors":[{"text":"Kwicklis, Edward M.","contributorId":25970,"corporation":false,"usgs":true,"family":"Kwicklis","given":"Edward","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":690984,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Healy, Richard W. 0000-0002-0224-1858 rwhealy@usgs.gov","orcid":"https://orcid.org/0000-0002-0224-1858","contributorId":658,"corporation":false,"usgs":true,"family":"Healy","given":"Richard","email":"rwhealy@usgs.gov","middleInitial":"W.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":690985,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70135745,"text":"70135745 - 1993 - Modelling the seasonality of subsurface light and primary production in the Arabian Sea","interactions":[],"lastModifiedDate":"2025-05-22T14:42:30.890779","indexId":"70135745","displayToPublicDate":"1993-11-25T12:00:00","publicationYear":"1993","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":"Modelling the seasonality of subsurface light and primary production in the Arabian Sea","docAbstract":"Seasonal changes in mixed-layer depth and phytoplankton biomass in the Arabian Sea are assessed with climatologies of ship-based hydrographic measurements and ocean-color observations from satellite. At the close of the intermonsoons in November and especially May, the open Arabian Sea resembles the stereotypic, unperturbed tropical ocean, with a thin oligotrophic mixed layer and a pronounced subsurface chlorophyll maximum. Both the northeast and southwest monsoons disrupt this typical tropical hydrography through mixed-layer deepening and eutrophication in the central and northern Arabian Sea. Computations using a spectral model of light penetration suggest that seasonal changes in mixed-layer thickness and phytoplankton concentration result in pronounced fluctuations through the annual cycle in the radiant flux reaching the base of the mixed layer. At the close of the fall and spring intermonsoons the base of the model euphotic zone is in the thermocline across all of the open Arabian Sea. The euphotic zone appears to rise into the mixed layer of the northern Arabian Sea during both the winter and summer monsoons. Strong seasonality in total primary production and its partitioning between the mixed layer and thermocline is predicted byb a photo-synthesis-irradiance model for a site in the western Arabian Sea (14.36° N, 57.38° E). Modeled mixed-layer primary production depicts an intense peak for the southwest monsoon and a secondary northeast monsoon peak separated by intermonsoon period of low production. During the fall and spring intermonsoons, in the presence of a subsurface clorophyll maximum, the model estimate of primary production in the thermocline exceeds that in the mixed layer. Our model calculations suggest that the subsurface clorophyll maximum present in the Arabian Sea during the spring intermonsoon is a precursor of the regional, summer, phytoplankton bloom.
","language":"English","publisher":"Inter-Research Science Publisher","publisherLocation":"Oldendorf","doi":"10.3354/meps101209","usgsCitation":"Brock, J., Sathyendranath, S., and Platt, T., 1993, Modelling the seasonality of subsurface light and primary production in the Arabian Sea: Marine Ecology Progress Series, v. 101, p. 209-221, https://doi.org/10.3354/meps101209.","productDescription":"13 p.","startPage":"209","endPage":"221","numberOfPages":"13","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":486976,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.3354/meps101209","text":"Publisher Index Page"},{"id":296708,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"101","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"549165cee4b0d0759afaad90","contributors":{"authors":[{"text":"Brock, John 0000-0002-5289-9332 jbrock@usgs.gov","orcid":"https://orcid.org/0000-0002-5289-9332","contributorId":2261,"corporation":false,"usgs":true,"family":"Brock","given":"John","email":"jbrock@usgs.gov","affiliations":[{"id":5061,"text":"National Cooperative Geologic Mapping and Landslide Hazards","active":true,"usgs":true}],"preferred":true,"id":536795,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sathyendranath, Shubha","contributorId":130995,"corporation":false,"usgs":false,"family":"Sathyendranath","given":"Shubha","email":"","affiliations":[],"preferred":false,"id":536796,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Platt, Trevor","contributorId":130996,"corporation":false,"usgs":false,"family":"Platt","given":"Trevor","email":"","affiliations":[],"preferred":false,"id":536797,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70186309,"text":"70186309 - 1993 - Impact crater outflows on Venus: Morphology and emplacement mechanisms","interactions":[],"lastModifiedDate":"2017-04-03T16:21:57","indexId":"70186309","displayToPublicDate":"1993-11-25T00:00:00","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2317,"text":"Journal of Geophysical Research E: Planets","active":true,"publicationSubtype":{"id":10}},"title":"Impact crater outflows on Venus: Morphology and emplacement mechanisms","docAbstract":"Many of the 932 impact craters discovered by the Magellan spacecraft at Venus are associated with lobate flows that originate at or near the crater rim. They extend for several to several hundred kilometers from the crater, and they commonly have a strong radar backscatter. A morphologic study of all identifiable crater outflows on Venus has revealed that many individual flows each consist of two areas, defined by distinct morphologic features. These two areas appear to represent two stages of deposition for each flow. The part of the flow that is generally deposited closest to the crater tends to be on the downrange side of the crater, flows in the downrange direction, and it is interpreted to be a late-stage ejecta. In many cases, this proximal part of the flow is too thin to completely bury the large blocks in subjacent ejecta deposits. Dendritic channels, present in many proximal flows, appear to have drained liquid from the proximal part in the downhill direction, and they debouch to feed the outer part of the flows. This distal part flows downhill, fills small grabens, and is ponded by ridges, behavior that mimics that of volcanic lava flows. The meandering and dendritic channels and the relation of the distal flows to topography strongly suggest that the distal portion is the result of coalescence and slow drainage of impact melt from the proximal portion. Impact melt forms a lining to the transient crater and mixes turbulently with solid clasts, and part of this mixture may be ejected to form the proximal part of the flow during the excavation stage of crater development. A statistical study of the Venusian craters has revealed that, in general, large craters produced by impacts with relatively low incidence angles to the surface are more likely to produce flows than small craters produced by higher-angle impacts. The greater flow production and downrange focusing of the proximal flows with decreasing incidence angle indicate a strong control of the flows by the impactor flight direction, and a high downrange velocity imparted to the proximal flow material in lower angle impacts. On the Moon, small flows interpreted to be composed of impact melt are observed atop the ejecta of large, fresh craters; on Earth, melt-rich suevite deposits form the uppermost layer of ejecta of some fresh craters. These features, albeit much smaller, may be analogous to the flows on Venus. Numerical models have predicted that larger volumes of impact melt would be produced on Venus than on the cooler terrestrial bodies due to high atmospheric and target temperatures, perhaps 3 times the volume produced on the Moon for a given crater diameter.
","language":"English","publisher":"Wiley","doi":"10.1029/93JE02605","usgsCitation":"Chadwick, D.J., and Schaber, G.G., 1993, Impact crater outflows on Venus: Morphology and emplacement mechanisms: Journal of Geophysical Research E: Planets, v. 98, no. E11, p. 20891-20902, https://doi.org/10.1029/93JE02605.","productDescription":"12 p.","startPage":"20891","endPage":"20902","costCenters":[],"links":[{"id":339099,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"98","issue":"E11","noUsgsAuthors":false,"publicationDate":"2012-09-21","publicationStatus":"PW","scienceBaseUri":"58e35f91e4b09da67997ed08","contributors":{"authors":[{"text":"Chadwick, D. John","contributorId":190382,"corporation":false,"usgs":false,"family":"Chadwick","given":"D.","email":"","middleInitial":"John","affiliations":[],"preferred":false,"id":688290,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Schaber, Gerald G.","contributorId":190383,"corporation":false,"usgs":false,"family":"Schaber","given":"Gerald","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":688291,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70186675,"text":"70186675 - 1993 - Rock-forming metals and Pb in modern Alaskan snow","interactions":[],"lastModifiedDate":"2017-04-07T09:39:47","indexId":"70186675","displayToPublicDate":"1993-11-20T00:00:00","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2316,"text":"Journal of Geophysical Research D: Atmospheres","active":true,"publicationSubtype":{"id":10}},"title":"Rock-forming metals and Pb in modern Alaskan snow","docAbstract":"Metal concentrations in annual and subannual increments of snowpack from the accumulation zone of a south central Alaska glacier indicate that the deposition of Pb with and upon snow is decoupled from that of rock dusts. Rock dusts accumulate, apparently as dry deposition, on the topmost, exposed surfaces of snowpacks in spring and summer, whereas Pb does not. Pb concentration is elevated throughout the latest one third of an annual snowpack, whereas that of rock dusts is not. For whole-year snowpacks, there is a generally sympathetic relationship among concentration of Pb, concentration of rock dust, degree of dominance of rock dusts over ocean solutes, and ferromagnesian character of the rock dusts; however, the fractional abundance of Pb in whole year samples may decrease when rock dust masses become large and/or when rock dusts dominate most strongly over salts. The metal suite chosen to characterize rock dusts and to distinguish them from ocean solutes gives detailed information about rock type of dust source areas and about the nature of the degraded rock products that are taken up, transported, and deposited by the atmosphere. Rock dusts are present at concentrations of only about 300 nanograms (ng) of dust per gram of snow in the Alaskan snowpacks. Concentrations of Pb in the Alaska snow samples are moderate, ranging from 0.1 to 0.3 ng Pb/g snow. This contrasts with larger Pb concentrations of 0.4 to 0.9 ng Pb/g snow in whole-year snowpack samples from the Sierra Nevada, California; with similar to smaller concentrations from north and south Greenland of about 0.04 ng Pb/g snow or less, and about 0.2 ng Pb/g snow or less, respectively, and with much smaller concentrations from Antarctica, now believed to range from a minimum of about 0.001 to a maximum of 0.005 (or 0.01) ng Pb/g snow.
","language":"English","publisher":"Wiley","doi":"10.1029/93JD02257","usgsCitation":"Hinkley, T.K., 1993, Rock-forming metals and Pb in modern Alaskan snow: Journal of Geophysical Research D: Atmospheres, v. 98, no. D11, p. 20537-20545, https://doi.org/10.1029/93JD02257.","productDescription":"9 p.","startPage":"20537","endPage":"20545","costCenters":[],"links":[{"id":339384,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"98","issue":"D11","noUsgsAuthors":false,"publicationDate":"2012-09-21","publicationStatus":"PW","scienceBaseUri":"58e8a54be4b09da6799d63eb","contributors":{"authors":[{"text":"Hinkley, Todd K. 0000-0001-8507-6271 thinkley@usgs.gov","orcid":"https://orcid.org/0000-0001-8507-6271","contributorId":1497,"corporation":false,"usgs":true,"family":"Hinkley","given":"Todd","email":"thinkley@usgs.gov","middleInitial":"K.","affiliations":[{"id":211,"text":"Crustal Geophysics and Geochemistry Science Center","active":true,"usgs":true}],"preferred":true,"id":690252,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70017927,"text":"70017927 - 1993 - Controls on geyser periodicity","interactions":[],"lastModifiedDate":"2025-09-15T16:56:17.505891","indexId":"70017927","displayToPublicDate":"1993-11-05T00:00:00","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3338,"text":"Science","active":true,"publicationSubtype":{"id":10}},"title":"Controls on geyser periodicity","docAbstract":"Geyser eruption frequency is not constant over time and has been shown to vary with small (≤10–6) strains induced by seismic events, atmospheric loading, and Earth tides. The geyser system is approximated as a permeable conduit of intensely fractured rock surrounded by a less permeable rock matrix. Numerical simulation of this conceptual model yields a set of parameters that controls geyser existence and periodicity. Much of the responsiveness to remote seismicity and other small strains in the Earth can be explained in terms of variations in permeability and lateral recharge rates.
","language":"English","publisher":"American Association for the Advancement of Science","doi":"10.1126/science.262.5135.889","issn":"00368075","usgsCitation":"Ingebritsen, S.E., and Rojstaczer, S., 1993, Controls on geyser periodicity: Science, v. 262, no. 5135, p. 889-892, https://doi.org/10.1126/science.262.5135.889.","productDescription":"4 p.","startPage":"889","endPage":"892","costCenters":[],"links":[{"id":228636,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"262","issue":"5135","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fbcfe4b0c8380cd4df94","contributors":{"authors":[{"text":"Ingebritsen, S. E.","contributorId":8078,"corporation":false,"usgs":true,"family":"Ingebritsen","given":"S.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":377930,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rojstaczer, S.A.","contributorId":54620,"corporation":false,"usgs":true,"family":"Rojstaczer","given":"S.A.","email":"","affiliations":[],"preferred":false,"id":377931,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70128770,"text":"70128770 - 1993 - Estimation of lipids and lean mass of migrating sandpipers","interactions":[],"lastModifiedDate":"2014-10-14T14:06:49","indexId":"70128770","displayToPublicDate":"1993-11-01T14:04:16","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3551,"text":"The Condor","active":true,"publicationSubtype":{"id":10}},"title":"Estimation of lipids and lean mass of migrating sandpipers","docAbstract":"Estimation of lean mass and lipid levels in birds involves the derivation of predictive equations that relate morphological measurements and, more recently, total body electrical conductivity (TOBEC) indices to known lean and lipid masses. Using cross-validation techniques, we evaluated the ability of several published and new predictive equations to estimate lean and lipid mass of Semipalmated Sandpipers (Calidris pusilla) and White-rumped Sandpipers (C. fuscicollis). We also tested ideas of Morton et al. (1991), who stated that current statistical approaches to TOBEC methodology misrepresent precision in estimating body fat. Three published interspecific equations using TOBEC indices predicted lean and lipid masses of our sample of birds with average errors of 8-28% and 53-155%, respectively. A new two-species equation relating lean mass and TOBEC indices revealed average errors of 4.6% and 23.2% in predicting lean and lipid mass, respectively. New intraspecific equations that estimate lipid mass directly from body mass, morphological measurements, and TOBEC indices yielded about a 13% error in lipid estimates. Body mass and morphological measurements explained a substantial portion of the variance (about 90%) in fat mass of both species. Addition of TOBEC indices improved the predictive model more for the smaller than for the larger sandpiper. TOBEC indices explained an additional 7.8% and 2.6% of the variance in fat mass and reduced the minimum breadth of prediction intervals by 0.95 g (32%) and 0.39 g (13%) for Semipalmated and White-rumped Sandpipers, respectively. The breadth of prediction intervals for models used to predict fat levels of individual birds must be considered when interpreting the resultant lipid estimates.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"The Condor","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Cooper Ornithological Club","publisherLocation":"Santa Clara, CA","doi":"10.2307/1369430","usgsCitation":"Skagen, S.K., Knopf, F.L., and Cade, B.S., 1993, Estimation of lipids and lean mass of migrating sandpipers: The Condor, v. 95, no. 4, p. 944-956, https://doi.org/10.2307/1369430.","productDescription":"13 p.","startPage":"944","endPage":"956","numberOfPages":"13","costCenters":[],"links":[{"id":295312,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":295311,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.2307/1369430"}],"volume":"95","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"543e3b23e4b0fd76af69cf04","contributors":{"authors":[{"text":"Skagen, Susan K. 0000-0002-6744-1244 skagens@usgs.gov","orcid":"https://orcid.org/0000-0002-6744-1244","contributorId":2009,"corporation":false,"usgs":true,"family":"Skagen","given":"Susan","email":"skagens@usgs.gov","middleInitial":"K.","affiliations":[{"id":291,"text":"Fort Collins Science Center","active":true,"usgs":true}],"preferred":false,"id":503214,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Knopf, Fritz L.","contributorId":45650,"corporation":false,"usgs":true,"family":"Knopf","given":"Fritz","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":503215,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Cade, Brian S. 0000-0001-9623-9849 cadeb@usgs.gov","orcid":"https://orcid.org/0000-0001-9623-9849","contributorId":1278,"corporation":false,"usgs":true,"family":"Cade","given":"Brian","email":"cadeb@usgs.gov","middleInitial":"S.","affiliations":[{"id":291,"text":"Fort Collins Science Center","active":true,"usgs":true}],"preferred":true,"id":503213,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70187189,"text":"70187189 - 1993 - An analytic solution of the stochastic storage problem applicable to soil water","interactions":[],"lastModifiedDate":"2018-03-06T14:32:45","indexId":"70187189","displayToPublicDate":"1993-11-01T00:00:00","publicationYear":"1993","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":"An analytic solution of the stochastic storage problem applicable to soil water","docAbstract":"The accumulation of soil water during rainfall events and the subsequent depletion of soil water by evaporation between storms can be described, to first order, by simple accounting models. When the alternating supplies (precipitation) and demands (potential evaporation) are viewed as random variables, it follows that soil-water storage, evaporation, and runoff are also random variables. If the forcing (supply and demand) processes are stationary for a sufficiently long period of time, an asymptotic regime should eventually be reached where the probability distribution functions of storage, evaporation, and runoff are stationary and uniquely determined by the distribution functions of the forcing. Under the assumptions that the potential evaporation rate is constant, storm arrivals are Poisson-distributed, rainfall is instantaneous, and storm depth follows an exponential distribution, it is possible to derive the asymptotic distributions of storage, evaporation, and runoff analytically for a simple balance model. A particular result is that the fraction of rainfall converted to runoff is given by (1 - R−1)/(eα(1−R−1) − R−1), in which R is the ratio of mean potential evaporation to mean rainfall and a is the ratio of soil water-holding capacity to mean storm depth. The problem considered here is analogous to the well-known problem of storage in a reservoir behind a dam, for which the present work offers a new solution for reservoirs of finite capacity. A simple application of the results of this analysis suggests that random, intraseasonal fluctuations of precipitation cannot by themselves explain the observed dependence of the annual water balance on annual totals of precipitation and potential evaporation.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/93WR01934","usgsCitation":"Milly, P., 1993, An analytic solution of the stochastic storage problem applicable to soil water: Water Resources Research, v. 29, no. 11, p. 3755-3758, https://doi.org/10.1029/93WR01934.","productDescription":"4 p.","startPage":"3755","endPage":"3758","costCenters":[],"links":[{"id":340423,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"29","issue":"11","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"59006082e4b0e85db3a5df0f","contributors":{"authors":[{"text":"Milly, P. C. D.","contributorId":100489,"corporation":false,"usgs":true,"family":"Milly","given":"P. C. D.","affiliations":[],"preferred":false,"id":692976,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70185435,"text":"70185435 - 1993 - Modeling steady-state methanogenic degradation of phenols in groundwater","interactions":[],"lastModifiedDate":"2019-03-04T19:01:01","indexId":"70185435","displayToPublicDate":"1993-11-01T00:00:00","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2233,"text":"Journal of Contaminant Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Modeling steady-state methanogenic degradation of phenols in groundwater","docAbstract":"Field and microcosm observations of methanogenic phenolic compound degradation indicate that Monod kinetics governs the substrate disappearance but overestimates the observed biomass. In this paper we present modeling results from an ongoing multidisciplinary study of methanogenic biodegradation of phenolic compounds in a sand and gravel aquifer contaminated by chemicals and wastes used in wood treatment. Field disappearance rates of four phenols match those determined in batch microcosm studies previously performed by E.M. Godsy and coworkers. The degradation process appears to be at steady-state because even after a sustained influx over several decades, the contaminants still are disappearing in transport downgradient. The existence of a steady-state degradation profile of each substrate together with a low biomass density in the aquifer indicate that the bacteria population is exhibiting no net growth. This may be due to the oligotrophic nature of the biomass population in which utilization and growth are approximately independent of concentration for most of the concentration range. Thus a constant growth rate should exist over much of the contaminated area which may in turn be balanced by an unusually high decay or maintenance rate due to hostile conditions or predation.
We present a statistical model relating measurements of water quality to associated errors in laboratory methods. Estimation of the model allows us to correct trends in water quality for long-term and short-term variations in laboratory measurement errors. An illustration of the bias correction method for a large national set of stream water quality and quality assurance data shows that reductions in the bias of estimates of water quality trend slopes are achieved at the expense of increases in the variance of these estimates. Slight improvements occur in the precision of estimates of trend in bias by using correlative information on bias and water quality to estimate random variations in measurement bias. The results of this investigation stress the need for reliable, long-term quality assurance data and efficient statistical methods to assess the effects of measurement errors on the detection of water quality trends.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/93WR01708","usgsCitation":"Alexander, R.B., Smith, R.A., and Schwarz, G., 1993, Correction of stream quality trends for the effects of laboratory measurement bias: Water Resources Research, v. 29, no. 11, p. 3821-3833, https://doi.org/10.1029/93WR01708.","productDescription":"14 p. ","startPage":"3821","endPage":"3833","costCenters":[],"links":[{"id":338958,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"29","issue":"11","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"58df6acae4b02ff32c6aea8d","contributors":{"authors":[{"text":"Alexander, Richard B. 0000-0001-9166-0626 ralex@usgs.gov","orcid":"https://orcid.org/0000-0001-9166-0626","contributorId":541,"corporation":false,"usgs":true,"family":"Alexander","given":"Richard","email":"ralex@usgs.gov","middleInitial":"B.","affiliations":[{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true},{"id":503,"text":"Office of Water Quality","active":true,"usgs":true}],"preferred":true,"id":687852,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Smith, Richard A. 0000-0003-2117-2269 rsmith1@usgs.gov","orcid":"https://orcid.org/0000-0003-2117-2269","contributorId":580,"corporation":false,"usgs":true,"family":"Smith","given":"Richard","email":"rsmith1@usgs.gov","middleInitial":"A.","affiliations":[{"id":37778,"text":"WMA - Integrated Modeling and Prediction Division","active":true,"usgs":true},{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true},{"id":503,"text":"Office of Water Quality","active":true,"usgs":true}],"preferred":true,"id":687853,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Schwarz, Gregory E. 0000-0002-9239-4566 gschwarz@usgs.gov","orcid":"https://orcid.org/0000-0002-9239-4566","contributorId":543,"corporation":false,"usgs":true,"family":"Schwarz","given":"Gregory E.","email":"gschwarz@usgs.gov","affiliations":[{"id":5067,"text":"Northeast Regional Director's Office","active":true,"usgs":true},{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true}],"preferred":false,"id":687854,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70180493,"text":"70180493 - 1993 - Prolonged swimming performance of northern squawfish","interactions":[],"lastModifiedDate":"2026-04-06T15:54:39.605022","indexId":"70180493","displayToPublicDate":"1993-11-01T00:00:00","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3624,"text":"Transactions of the American Fisheries Society","active":true,"publicationSubtype":{"id":10}},"title":"Prolonged swimming performance of northern squawfish","docAbstract":"We determined the prolonged swimming performance of two size-classes of northern squawfish Ptychocheilus oregonensis at 12 and 18°C. The percentage of fish fatigued was positively related to water velocity and best described by an exponential model. At 12°C, the velocity at which 50% of the fish fatigued (FV50) was estimated to be 2.91 fork lengths per second (FL/s; 100 cm/s) for medium-sized fish (30–39 cm) and 2.45 FL/s (104 cm/s) for large fish (40–49 cm). At 18°C, estimated FV50 was 3.12 FL/s (107 cm/s) for medium fish and 2.65 FL/s (112 cm/s) for large fish. Rate of change in percent fatigue was affected by fish size and water temperature. Large fish fatigued at a higher rate than medium-sized fish; all fish fatigued faster at 12 than at 18°C. The mean times to fatigue at velocities of 102–115 cm/s ranged from 14 to 28 min and were not affected by fish size or water temperature. Our results indicate that water velocities from 100 to 130 cm/s may exclude or reduce predation by northern squawfish around juvenile salmonid bypass outfalls at Columbia River dams, at least during certain times of the year. We recommend that construction or modification of juvenile salmonid bypass facilities place the outfall in an area of high water velocity and distant from eddies, submerged cover, and littoral areas.
","language":"English","publisher":"American Fisheries Society","doi":"10.1577/1548-8659(0)122<1104:PSPONS>2.3.CO;2","usgsCitation":"Mesa, M.G., and Olson, T.M., 1993, Prolonged swimming performance of northern squawfish: Transactions of the American Fisheries Society, v. 122, no. 6, p. 1104-1110, https://doi.org/10.1577/1548-8659(0)122<1104:PSPONS>2.3.CO;2.","productDescription":"7 p.","startPage":"1104","endPage":"1110","costCenters":[{"id":654,"text":"Western Fisheries Research Center","active":true,"usgs":true}],"links":[{"id":334381,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Oregon, Washington","otherGeospatial":"Columbia River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -125.65623974647107,\n 49.01412527805786\n ],\n [\n -125.65623974647107,\n 44.77025605659105\n ],\n [\n -116.95972607862396,\n 44.77025605659105\n ],\n [\n -116.95972607862396,\n 49.01412527805786\n ],\n [\n -125.65623974647107,\n 49.01412527805786\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"122","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58905efbe4b072a7ac0cada9","contributors":{"authors":[{"text":"Mesa, Matthew G. mmesa@usgs.gov","contributorId":3423,"corporation":false,"usgs":true,"family":"Mesa","given":"Matthew","email":"mmesa@usgs.gov","middleInitial":"G.","affiliations":[{"id":654,"text":"Western Fisheries Research Center","active":true,"usgs":true}],"preferred":true,"id":661755,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Olson, Todd M.","contributorId":178862,"corporation":false,"usgs":false,"family":"Olson","given":"Todd","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":661756,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":1003157,"text":"1003157 - 1993 - Growth and mortality of larval sunfish in backwaters of the upper Mississippi River","interactions":[],"lastModifiedDate":"2026-04-06T15:44:24.315054","indexId":"1003157","displayToPublicDate":"1993-11-01T00:00:00","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3624,"text":"Transactions of the American Fisheries Society","active":true,"publicationSubtype":{"id":10}},"title":"Growth and mortality of larval sunfish in backwaters of the upper Mississippi River","docAbstract":"We estimated the growth and mortality of larval sunfish Lepomis spp. in backwater habitats of the upper Mississippi River with an otolith‐based method and a length‐based method. Fish were sampled with plankton nets at one station in Navigation Pools 8 and 14 in 1989 and at two stations in Pool 8 in 1990. For both methods, growth was modeled with an exponential equation, and instantaneous mortality was estimated by regressing the natural logarithm of fish catch for each 1‐mm size‐group against the estimated age of the group, which was derived from the growth equations. At two of the stations, the otolith‐based method provided more precise estimates of sunfish growth than the length‐based method. We were able to compare length‐based and otolith‐based estimates of sunfish mortality only at the two stations where we caught the largest numbers of sunfish. Estimates of mortality were similar for both methods in Pool 14, where catches were higher, but the length‐based method gave significantly higher estimates in Pool 8, where the catches were lower. The otolith‐based method required more laboratory analysis, but provided better estimates of the growth and mortality than the length‐based method when catches were low. However, the length‐based method was more cost‐effective for estimating growth and mortality when catches were large.
","language":"English","publisher":"American Fisheries Society","doi":"10.1577/1548-8659(1993)122<1080:GAMOLS>2.3.CO;2","issn":"00028487","usgsCitation":"Zigler, S.J., and Jennings, C., 1993, Growth and mortality of larval sunfish in backwaters of the upper Mississippi River: Transactions of the American Fisheries Society, v. 122, no. 6, p. 1080-1087, https://doi.org/10.1577/1548-8659(1993)122<1080:GAMOLS>2.3.CO;2.","productDescription":"8 p.","startPage":"1080","endPage":"1087","costCenters":[{"id":606,"text":"Upper Midwest Environmental Sciences Center","active":true,"usgs":true}],"links":[{"id":186261,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"upper Mississippi River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -93.31281541718155,\n 45.107429570207614\n ],\n [\n -91.63708360378831,\n 43.51116443180767\n ],\n [\n -90.85224177489205,\n 42.0502181844025\n ],\n [\n -91.79669684428936,\n 40.28270221332478\n ],\n [\n -90.71586306496908,\n 38.373707744056794\n ],\n [\n -89.63502928564883,\n 36.46471327478881\n ],\n [\n -88.87584674381966,\n 36.522335909403296\n ],\n [\n -90.1090290077692,\n 38.868184796060966\n ],\n [\n -91.06453389998158,\n 40.02057200622481\n ],\n [\n -90.86123232947048,\n 40.72582832750582\n ],\n [\n -89.8408880753197,\n 41.99919878732316\n ],\n [\n -90.81776494730315,\n 43.077488380741585\n ],\n [\n -91.19446180434727,\n 43.98010067685425\n ],\n [\n -92.60242846451888,\n 45.27523959728171\n ],\n [\n -93.31281541718155,\n 45.107429570207614\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"122","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4afbe4b07f02db696120","contributors":{"authors":[{"text":"Zigler, S. J.","contributorId":21513,"corporation":false,"usgs":true,"family":"Zigler","given":"S.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":312850,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jennings, Cecil A.","contributorId":38504,"corporation":false,"usgs":true,"family":"Jennings","given":"Cecil A.","affiliations":[],"preferred":false,"id":312851,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70200704,"text":"70200704 - 1993 - Economics and the national oil and gas assessment: The case of onshore northern Alaska","interactions":[],"lastModifiedDate":"2023-01-23T18:02:25.657144","indexId":"70200704","displayToPublicDate":"1993-10-16T13:49:30","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":701,"text":"American Association of Petroleum Geologists Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Economics and the national oil and gas assessment: The case of onshore northern Alaska","docAbstract":"The National Oil and Gas Assessment of undiscovered recoverable conventional oil and gas resources assigned nearly 36% of the undiscovered U.S. onshore oil resources and 28% of the commercially developable undiscovered oil resources to onshore northern Alaska. Economic screening models were applied to the geologic play assessment to estimate the commercially developable resources. This paper presents the geologic and economic assessment methodology and results; it also focuses on the robustness of estimates of the commercially developable onshore resources to changes in economic assumptions.
With the economic assumptions used in the national assessment, about 60% or 6.49 billion bbl of oil of the recoverable undiscovered resources of 10.76 billion bbl of oil assessed in fields larger than 1 million bbl of oil are estimated to be commercially developable. Changes in facilities costs induced the most significant cost-related response in the commercially developable resource estimates. Price increases or cost reductions that reduce the minimum commercially developable field size to 250 million bbl from the base case size of 380 million bbl added 1 billion bbl of oil to the commercially developable resources. If, through facilities sharing or satellite-field development, the minimum commercial field size is reduced to just below 100 million bbl, estimated developable oil woul increase to 9.17 billion bbl of oil or more than 85% of the assessed recoverable oil in onshore plays.
","language":"English","publisher":"American Association of Petroleum Geologists","doi":"10.1306/BDFF8C72-1718-11D7-8645000102C1865D","usgsCitation":"Attanasi, E., Bird, K.J., and Mast, R.F., 1993, Economics and the national oil and gas assessment: The case of onshore northern Alaska: American Association of Petroleum Geologists Bulletin, v. 77, no. 3, p. 491-504, https://doi.org/10.1306/BDFF8C72-1718-11D7-8645000102C1865D.","productDescription":"14 p.","startPage":"491","endPage":"504","costCenters":[{"id":241,"text":"Eastern Energy Resources Science Center","active":true,"usgs":true},{"id":255,"text":"Energy Resources Program","active":true,"usgs":true}],"links":[{"id":358906,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Alaska","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -145.48080420268553,\n 72.71391257340173\n ],\n [\n -170.8889081934487,\n 72.71391257340173\n ],\n [\n -170.8889081934487,\n 66.46646934602157\n ],\n [\n -145.48080420268553,\n 66.46646934602157\n ],\n [\n -145.48080420268553,\n 72.71391257340173\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"77","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5c111a1ce4b034bf6a8194de","contributors":{"authors":[{"text":"Attanasi, Emil D. 0000-0001-6845-7160 attanasi@usgs.gov","orcid":"https://orcid.org/0000-0001-6845-7160","contributorId":198728,"corporation":false,"usgs":true,"family":"Attanasi","given":"Emil D.","email":"attanasi@usgs.gov","affiliations":[{"id":241,"text":"Eastern Energy Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":750176,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bird, Kenneth J. kbird@usgs.gov","contributorId":1015,"corporation":false,"usgs":true,"family":"Bird","given":"Kenneth","email":"kbird@usgs.gov","middleInitial":"J.","affiliations":[{"id":255,"text":"Energy Resources Program","active":true,"usgs":true}],"preferred":true,"id":750177,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mast, R. F.","contributorId":210210,"corporation":false,"usgs":false,"family":"Mast","given":"R.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":750178,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70243547,"text":"70243547 - 1993 - Optimization of an extraction procedure for the accurate determination of total tin in eighteen Geological Survey of Japan rock reference materials","interactions":[],"lastModifiedDate":"2023-05-11T13:31:55.596345","indexId":"70243547","displayToPublicDate":"1993-10-11T08:23:27","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":14421,"text":"Analytical Sciences","onlineIssn":"1348-2246","active":true,"publicationSubtype":{"id":10}},"title":"Optimization of an extraction procedure for the accurate determination of total tin in eighteen Geological Survey of Japan rock reference materials","docAbstract":"A fusion-extraction procedure for the determination of total tin in rocks and sediments by graphite furnace atomic absorption spectrometry (GFAAS) was reexamined and modified to obtain the optimum accuracy and precision. Several variations based on increases in the sample weight or extraction ratio were compared based on the determination of tin in 18 Geological Survey of Japan (GSJ) reference materials. The most accurate and precise procedure was found to be an 8:1 extraction of a 0.5 g rock sample fused with lithium metaborate and dissolved in 7.5% hydrochloric acid, using a 4% solution of trioctylphosphine oxide in methyl isobutyl ketone (TOPO-MIBK). Rocks containing <I ug/g total tin require a 0.5 g sample size for the utmost accuracy. Utilizing these modifications, tin concentrations were found to be within 0.1 ug/g for all of the GSJ reference standards with the exception of the rhyolites. Values are reported for the total tin content of three new GSJ reference materials, namely, JLk-1, JLs-1, and JDo-1.
","language":"English","publisher":"Springer","doi":"10.2116/analsci.9.681","usgsCitation":"Elsheimer, H., 1993, Optimization of an extraction procedure for the accurate determination of total tin in eighteen Geological Survey of Japan rock reference materials: Analytical Sciences, v. 9, p. 681-685, https://doi.org/10.2116/analsci.9.681.","productDescription":"5 p.","startPage":"681","endPage":"685","costCenters":[],"links":[{"id":494204,"rank":0,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.2116/analsci.9.681","text":"Publisher Index Page"},{"id":416962,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"9","noUsgsAuthors":false,"publicationDate":"1993-10-11","publicationStatus":"PW","contributors":{"authors":[{"text":"Elsheimer, H.N.","contributorId":77523,"corporation":false,"usgs":true,"family":"Elsheimer","given":"H.N.","email":"","affiliations":[],"preferred":false,"id":872304,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70185441,"text":"70185441 - 1993 - Simulating the volatilization of solvents in unsaturated soils during laboratory and field infiltration experiments","interactions":[],"lastModifiedDate":"2019-03-06T05:48:22","indexId":"70185441","displayToPublicDate":"1993-10-01T00:00:00","publicationYear":"1993","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":"Simulating the volatilization of solvents in unsaturated soils during laboratory and field infiltration experiments","docAbstract":"This paper describes laboratory and field experiments which were conducted to study the dynamics of trichloroethylene (TCE) as it volatilized from contaminated groundwater and diffused in the presence of infiltrating water through the unsaturated soil zone to the land surface. The field experiments were conducted at the Picatinny Arsenal, which is part of the United States Geological Survey Toxic Substances Hydrology Program. In both laboratory and field settings the gas and water phase concentrations of TCE were not in equilibrium during infiltration. Gas-water mass transfer rate constants were calibrated to the experimental data using a model in which the water phase was treated as two phases: a mobile water phase and an immobile water phase. The mass transfer limitations of a volatile organic compound between the gas and liquid phases were described explicitly in the model. In the laboratory experiment the porous medium was nonsorbing, and water infiltration rates ranged from 0.076 to 0.28 cm h−1. In the field experiment the water infiltration rate was 0.34 cm h−1, and sorption onto the soil matrix was significant. The laboratory-calibrated gas-water mass transfer rate constant is 3.3×10−4 h−1 for an infiltration rate of 0.076 cm h−1 and 1.4×10−3 h−1 for an infiltration rate of 0.28 cm h−1. The overall mass transfer rate coefficients, incorporating the contribution of mass transfer between mobile and immobile water phases and the variation of interfacial area with moisture content, range from 3×10−4 h−1 to 1×10−2 h−1. A power law model relates the gas-water mass transfer rate constant to the infiltration rate and the fraction of the water phase which is mobile. It was found that the results from the laboratory experiments could not be extrapolated to the field. In order to simulate the field experiment the very slow desorption of TCE from the soil matrix was incorporated into the mathematical model. When desorption from the soil matrix was added to the model, the calibrated gas-water mass transfer rate constant is 2 orders of magnitude lower than that predicted using the power law model developed for the nonsorbing laboratory soil.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/93WR01414","usgsCitation":"Cho, H.J., Jaffe, P.R., and Smith, J., 1993, Simulating the volatilization of solvents in unsaturated soils during laboratory and field infiltration experiments: Water Resources Research, v. 29, no. 10, p. 3329-3342, https://doi.org/10.1029/93WR01414.","productDescription":"14 p. ","startPage":"3329","endPage":"3342","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338031,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"29","issue":"10","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"58d38d3de4b0236b68f98efc","contributors":{"authors":[{"text":"Cho, H. Jean","contributorId":189545,"corporation":false,"usgs":false,"family":"Cho","given":"H.","email":"","middleInitial":"Jean","affiliations":[],"preferred":false,"id":685585,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jaffe, Peter R.","contributorId":22503,"corporation":false,"usgs":true,"family":"Jaffe","given":"Peter","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":685586,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Smith, James A.","contributorId":68718,"corporation":false,"usgs":true,"family":"Smith","given":"James A.","affiliations":[],"preferred":false,"id":685587,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70128741,"text":"70128741 - 1993 - Use of mesoscale models for simulation of seasonal weather and climate change for the Rocky Mountain States","interactions":[],"lastModifiedDate":"2018-02-21T15:51:54","indexId":"70128741","displayToPublicDate":"1993-09-30T12:41:00","publicationYear":"1993","noYear":false,"publicationType":{"id":4,"text":"Book"},"publicationSubtype":{"id":12,"text":"Conference publication"},"title":"Use of mesoscale models for simulation of seasonal weather and climate change for the Rocky Mountain States","docAbstract":"No abstract available.","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Second international conference/workshop on integrating geographic information systems and environmental modelling","largerWorkSubtype":{"id":12,"text":"Conference publication"},"conferenceTitle":"Second international conference/workshop on integrating geographic information systems and environmental modelling","conferenceDate":"September 26, 1993","conferenceLocation":"Breckenridge, CO","language":"English","publisher":"National center for Geographic Information and Analysis","publisherLocation":"Breckenridge, CO","usgsCitation":"Pielke, R.A., Baron, J., Chase, T., Copeland, J., Kittel, T.G., Lee, T.J., Walko, R., and Zeng, W., 1993, Use of mesoscale models for simulation of seasonal weather and climate change for the Rocky Mountain States, 1 p.","productDescription":"1 p.","numberOfPages":"1","costCenters":[],"links":[{"id":295289,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"543e3b33e4b0fd76af69cf3d","contributors":{"authors":[{"text":"Pielke, R. A.","contributorId":13163,"corporation":false,"usgs":true,"family":"Pielke","given":"R.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":503165,"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":503170,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Chase, T.","contributorId":74321,"corporation":false,"usgs":true,"family":"Chase","given":"T.","affiliations":[],"preferred":false,"id":503172,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Copeland, J.","contributorId":49293,"corporation":false,"usgs":true,"family":"Copeland","given":"J.","affiliations":[],"preferred":false,"id":503169,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Kittel, Timothy G.F.","contributorId":66612,"corporation":false,"usgs":true,"family":"Kittel","given":"Timothy","email":"","middleInitial":"G.F.","affiliations":[],"preferred":false,"id":503171,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Lee, T. J.","contributorId":26234,"corporation":false,"usgs":true,"family":"Lee","given":"T.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":503166,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Walko, R.","contributorId":28187,"corporation":false,"usgs":true,"family":"Walko","given":"R.","affiliations":[],"preferred":false,"id":503167,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Zeng, W.","contributorId":48893,"corporation":false,"usgs":true,"family":"Zeng","given":"W.","email":"","affiliations":[],"preferred":false,"id":503168,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}} ,{"id":70017978,"text":"70017978 - 1993 - Sharpness of upper-mantle discontinuities determined from high-frequency reflections","interactions":[],"lastModifiedDate":"2025-05-28T14:53:12.305109","indexId":"70017978","displayToPublicDate":"1993-09-09T00:00:00","publicationYear":"1993","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2840,"text":"Nature","active":true,"publicationSubtype":{"id":10}},"title":"Sharpness of upper-mantle discontinuities determined from high-frequency reflections","docAbstract":"An understanding of the nature of seismic discontinuities in the Earth's upper mantle is important for understanding mantle processes: in particular, the amplitude and sharpness of these discontinuities are critical for assessing models of upper-mantle phase changes and chemical layering. So far, seismic studies aimed at determining the thickness and lateral variability of upper-mantle discontinuities have yielded equivocal results, particularly for the discontinuity at 410km depth1,2. Here we present short-period (0.8–2.0 s) recordings of upper-mantle precursors to the seismic phase P′P′ (PKPPKP) from two South American earthquakes recorded by the ∼700-station short-period array in California. Our results show that the 410- and 660-km discontinuities beneath the Indian Ocean are locally simple and sharp, corresponding to transi-tion zones of 4 km or less. These observations pose problems for mineral physics models3–5, which predict a transitional thickness greater than 6 km for the peridotite to β-spinel phase transition. In contrast to the results of long-period studies6,7, we observe no short-period arrivals from near 520 km depth.
","language":"English","publisher":"Springer Nature","doi":"10.1038/365147a0","issn":"00280836","usgsCitation":"Benz, H., and Vidale, J., 1993, Sharpness of upper-mantle discontinuities determined from high-frequency reflections: Nature, v. 365, no. 6442, p. 147-150, https://doi.org/10.1038/365147a0.","productDescription":"4 p.","startPage":"147","endPage":"150","costCenters":[],"links":[{"id":228639,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"365","issue":"6442","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8e52e4b08c986b318888","contributors":{"authors":[{"text":"Benz, H.M.","contributorId":21594,"corporation":false,"usgs":true,"family":"Benz","given":"H.M.","email":"","affiliations":[],"preferred":false,"id":378094,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Vidale, J.E.","contributorId":55849,"corporation":false,"usgs":true,"family":"Vidale","given":"J.E.","email":"","affiliations":[],"preferred":false,"id":378095,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ]}