Diffuse emissions of CO2 are known to be large around some volcanoes and hydrothermal areas. Accumulation-chamber measurements of CO2 flux are increasingly used to estimate the total magmatic or metamorphic CO2 released from such areas. To assess the performance of accumulation chamber systems at fluxes one to three orders of magnitude higher than normally encountered in soil respiration studies, a test system was constructed in the laboratory where known fluxes could be maintained through dry sand. Steady-state gas concentration profiles and fractionation effects observed in the 30-cm sand column nearly match those predicted by the Stefan-Maxwell equations, indicating that the test system was functioning successfully as a uniform porous medium. Eight groups of investigators tested their accumulation chamber equipment, all configured with continuous infrared gas analyzers (IRGA), in this system. Over a flux range of ∼200–12,000 g m−2day−1, 90% of their 203 flux measurements were 0–25% lower than the imposed flux with a mean difference of −12.5%. Although this difference would seem to be within the range of acceptability for many geologic investigations, some potential sources for larger errors were discovered. A steady-state pressure gradient of −20 Pa/m was measured in the sand column at a flux of 11,200 g m−2 day−1. The derived permeability (50 darcies) was used in the dusty-gas model (DGM) of transport to quantify various diffusive and viscous flux components. These calculations were used to demonstrate that accumulation chambers, in addition to reducing the underlying diffusive gradient, severely disrupt the steady-state pressure gradient. The resultant diversion of the net gas flow is probably responsible for the systematically low flux measurements. It was also shown that the fractionating effects of a viscous CO2 efflux against a diffusive influx of air will have a major impact on some important geochemical indicators, such as N2/Ar, δ15N–N2, and 4He/22Ne.
Genetic markers that differ in mode of inheritance and rate of evolution (a sex-linked Z-specific microsatellite locus, five biparentally inherited microsatellite loci, and maternally inherited mitochondrial [mtDNA] sequences) were used to evaluate the degree of spatial genetic structuring at macro- and microgeographic scales, among breeding regions and local nesting populations within each region, respectively, for a migratory sea duck species, the spectacled eider (Somateria fisheri). Disjunct and declining breeding populations coupled with sex-specific differences in seasonal migratory patterns and life history provide a series of hypotheses regarding rates and directionality of gene flow among breeding populations from the Indigirka River Delta, Russia, and the North Slope and Yukon-Kuskokwim Delta, Alaska. The degree of differentiation in mtDNA haplotype frequency among breeding regions and populations within regions was high (ϕCT = 0.189, P < 0.01; ϕSC = 0.059, P < 0.01, respectively). Eleven of 17 mtDNA haplotypes were restricted to a single breeding region. Genetic differences among regions were considerably lower for nuclear DNA loci (sex-linked: ϕST = 0.001, P > 0.05; biparentally inherited microsatellites: mean θ = 0.001, P > 0.05) than was observed for mtDNA. Using models explicitly designed for uniparental and biparentally inherited genes, estimates of spatial divergence based on nuclear and mtDNA data together with elements of the species' breeding ecology were used to estimate effective population size and degree of male and female gene flow. Differences in the magnitude and spatial patterns of gene correlations for maternally inherited and nuclear genes revealed that females exhibit greater natal philopatry than do males. Estimates of generational female and male rates of gene flow among breeding regions differed markedly (3.67 × 10−4 and 1.28 × 10−2, respectively). Effective population size for mtDNA was estimated to be at least three times lower than that for biparental genes (30,671 and 101,528, respectively). Large disparities in population sizes among breeding areas greatly reduces the proportion of total genetic variance captured by dispersal, which may accelerate rates of inbreeding (i.e., promote higher coancestries) within populations due to nonrandom pairing of males with females from the same breeding population.
","language":"English","publisher":"Society for the Study of Evolution","doi":"10.1554/0014-3820(2001)055[2105:SBGFIS]2.0.CO;2","issn":"00143820","usgsCitation":"Scribner, K.T., Petersen, M.R., Fields, R.L., Talbot, S.L., Pearce, J.M., and Chesser, R.K., 2001, Sex-biased gene flow in spectacled eiders (Anatidae): Inferences from molecular markers with contrasting modes of inheritance: Evolution, v. 55, no. 10, p. 2105-2115, https://doi.org/10.1554/0014-3820(2001)055[2105:SBGFIS]2.0.CO;2.","productDescription":"11 p.","startPage":"2105","endPage":"2115","costCenters":[{"id":114,"text":"Alaska Science Center","active":true,"usgs":true}],"links":[{"id":233748,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Russia, United States","state":"Alaska","otherGeospatial":"Bering Sea, Indigirka River Delta, North Slope [Alaska], Yukon-Kuskokwim Delta, Alaska","volume":"55","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8daee4b08c986b3184d3","contributors":{"authors":[{"text":"Scribner, Kim T.","contributorId":146113,"corporation":false,"usgs":false,"family":"Scribner","given":"Kim","email":"","middleInitial":"T.","affiliations":[{"id":16582,"text":"Department of Fisheries and Wildlife and Department of Zoology, 480 Wilson Rd. 13 Natural Resources Building, Michigan State University, East Lansing, MI 48824","active":true,"usgs":false},{"id":135,"text":"Biological Resources Division","active":false,"usgs":true}],"preferred":false,"id":394743,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Petersen, Margaret R. 0000-0001-6082-3189 mrpetersen@usgs.gov","orcid":"https://orcid.org/0000-0001-6082-3189","contributorId":167729,"corporation":false,"usgs":true,"family":"Petersen","given":"Margaret","email":"mrpetersen@usgs.gov","middleInitial":"R.","affiliations":[{"id":117,"text":"Alaska Science Center Biology WTEB","active":true,"usgs":true}],"preferred":true,"id":394742,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Fields, Raymond L.","contributorId":182354,"corporation":false,"usgs":true,"family":"Fields","given":"Raymond","email":"","middleInitial":"L.","affiliations":[{"id":106,"text":"Alaska Biological Science Center","active":false,"usgs":true}],"preferred":false,"id":394739,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Talbot, Sandra L. 0000-0002-3312-7214 stalbot@usgs.gov","orcid":"https://orcid.org/0000-0002-3312-7214","contributorId":140512,"corporation":false,"usgs":true,"family":"Talbot","given":"Sandra","email":"stalbot@usgs.gov","middleInitial":"L.","affiliations":[{"id":117,"text":"Alaska Science Center Biology WTEB","active":true,"usgs":true},{"id":114,"text":"Alaska Science Center","active":true,"usgs":true}],"preferred":true,"id":394741,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Pearce, John M. 0000-0002-8503-5485 jpearce@usgs.gov","orcid":"https://orcid.org/0000-0002-8503-5485","contributorId":181766,"corporation":false,"usgs":true,"family":"Pearce","given":"John","email":"jpearce@usgs.gov","middleInitial":"M.","affiliations":[{"id":117,"text":"Alaska Science Center Biology WTEB","active":true,"usgs":true},{"id":114,"text":"Alaska Science Center","active":true,"usgs":true}],"preferred":true,"id":394744,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Chesser, Ronald K.","contributorId":113098,"corporation":false,"usgs":true,"family":"Chesser","given":"Ronald","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":394740,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70022734,"text":"70022734 - 2001 - Coastline complexity: A parameter for functional classification of coastal environments","interactions":[],"lastModifiedDate":"2012-03-12T17:20:40","indexId":"70022734","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Coastline complexity: A parameter for functional classification of coastal environments","docAbstract":"To understand the role of the world's coastal zone (CZ) in global biogeochemical fluxes (particularly those of carbon, nitrogen, phosphorus, and sediments) we must generalise from a limited number of observations associated with a few well-studied coastal systems to the global scale. Global generalisation must be based on globally available data and on robust techniques for classification and upscaling. These requirements impose severe constraints on the set of variables that can be used to extract information about local CZ functions such as advective and metabolic fluxes, and differences resulting from changes in biotic communities. Coastal complexity (plan-view tortuosity of the coastline) is a potentially useful parameter, since it interacts strongly with both marine and terrestrial forcing functions to determine coastal energy regimes and water residence times, and since 'open' vs. 'sheltered' categories are important components of most coastal habitat classification schemes. This study employs the World Vector Shoreline (WVS) dataset, originally developed at a scale of 1:250 000. Coastline complexity measures are generated using a modification of the Angle Measurement Technique (AMT), in which the basic measurement is the angle between two lines of specified length drawn from a selected point to the closest points of intersection with the coastline. Repetition of these measurements for different lengths at the same point yields a distribution of angles descriptive of the extent and scale of complexity in the vicinity of that point; repetition of the process at different points on the coast provides a basis for comparing both the extent and the characteristic scale of coastline variation along different reaches of the coast. The coast of northwestern Mexico (Baja California and the Gulf of California) was used as a case study for initial development and testing of the method. The characteristic angle distribution plots generated by the AMT analysis were clustered using LOICZVIEW, a high dimensionality clustering routine developed for large-scale coastal classification studies. The results show distinctive differences in coastal environments that have the potential for interpretation in terms of both biotic and hydrogeochemical environments, and that can be related to the resolution limits and uncertainties of the shoreline data used. These objective, quantitative measures of coastal complexity as a function of scale can be further developed and combined with other data sets to provide a key component of functional classification of coastal environments. ?? 2001 Elsevier Science B.V. All rights reserved.","largerWorkTitle":"Journal of Sea Research","language":"English","doi":"10.1016/S1385-1101(01)00073-9","issn":"13851101","usgsCitation":"Bartley, J., Buddemeier, R., and Bennett, D., 2001, Coastline complexity: A parameter for functional classification of coastal environments, in Journal of Sea Research, v. 46, no. 2, p. 87-97, https://doi.org/10.1016/S1385-1101(01)00073-9.","startPage":"87","endPage":"97","numberOfPages":"11","costCenters":[],"links":[{"id":478858,"rank":10000,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.589.3057","text":"External Repository"},{"id":208127,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S1385-1101(01)00073-9"},{"id":233602,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"46","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f794e4b0c8380cd4cbbc","contributors":{"authors":[{"text":"Bartley, J.D.","contributorId":88533,"corporation":false,"usgs":true,"family":"Bartley","given":"J.D.","email":"","affiliations":[],"preferred":false,"id":394701,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Buddemeier, R. W.","contributorId":86492,"corporation":false,"usgs":true,"family":"Buddemeier","given":"R. W.","affiliations":[],"preferred":false,"id":394700,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bennett, D.A.","contributorId":98919,"corporation":false,"usgs":true,"family":"Bennett","given":"D.A.","email":"","affiliations":[],"preferred":false,"id":394702,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024035,"text":"70024035 - 2001 - Experimental observations of pressure oscillations and flow regimes in an analogue volcanic system","interactions":[],"lastModifiedDate":"2022-11-17T18:23:02.915833","indexId":"70024035","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","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":"Experimental observations of pressure oscillations and flow regimes in an analogue volcanic system","docAbstract":"Gas-liquid flows, designed to be analogous to those in volcanic conduits, are generated in the laboratory using organic gas-gum rosin mixtures expanding in a vertically mounted tube. The expanding fluid shows a range of both flow and pressure oscillation behaviors. Weakly supersaturated source liquids produce a low Reynolds number flow with foam expanding from the top surface of a liquid that exhibits zero fluid velocity at the tube wall; i.e., the conventional \"no-slip\" boundary condition. Pressure oscillations, often with strong long-period characteristics and consistent with longitudinal and radial resonant oscillation modes, are detected in these fluids. Strongly supersaturated source liquids generate more energetic flows that display a number of flow regimes. These regimes include a static liquid source, viscous flow, detached flow (comprising gas-pockets-at-wall and foam-in-gas annular flow, therefore demonstrating strong radial heterogeneity), and a fully turbulent transonic fragmented or mist flow. Each of these flow regimes displays characteristic pressure oscillations that can be related to resonance of flow features or wall impact phenomena. The pressure oscillations are produced by the degassing processes without the need of elastic coupling to the confining medium or flow restrictors and valvelike features. The oscillatory behavior of the experimental flows is compared to seismoacoustic data from a range of volcanoes where resonant oscillation of the fluid within the conduit is also often invoked as controlling the observed oscillation frequencies. On the basis of the experimental data we postulate on the nature of seismic signals that may be measured during large-scale explosive activity.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000JB900376","issn":"01480227","usgsCitation":"Lane, S., Chouet, B., Phillips, J., Dawson, P., Ryan, G., and Hurst, E., 2001, Experimental observations of pressure oscillations and flow regimes in an analogue volcanic system: Journal of Geophysical Research B: Solid Earth, v. 106, no. B4, p. 6461-6476, https://doi.org/10.1029/2000JB900376.","productDescription":"16 p.","startPage":"6461","endPage":"6476","costCenters":[],"links":[{"id":478866,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2000jb900376","text":"Publisher Index Page"},{"id":232097,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"106","issue":"B4","noUsgsAuthors":false,"publicationDate":"2001-04-10","publicationStatus":"PW","scienceBaseUri":"505a0dd9e4b0c8380cd53212","contributors":{"authors":[{"text":"Lane, S.J.","contributorId":28771,"corporation":false,"usgs":true,"family":"Lane","given":"S.J.","email":"","affiliations":[],"preferred":false,"id":399752,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chouet, B. A.","contributorId":31813,"corporation":false,"usgs":true,"family":"Chouet","given":"B. A.","affiliations":[],"preferred":false,"id":399753,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Phillips, J.C.","contributorId":69329,"corporation":false,"usgs":true,"family":"Phillips","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":399756,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Dawson, P. 0000-0003-4065-0588","orcid":"https://orcid.org/0000-0003-4065-0588","contributorId":49529,"corporation":false,"usgs":true,"family":"Dawson","given":"P.","affiliations":[],"preferred":false,"id":399755,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Ryan, G.A.","contributorId":82089,"corporation":false,"usgs":true,"family":"Ryan","given":"G.A.","email":"","affiliations":[],"preferred":false,"id":399757,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Hurst, E.","contributorId":36711,"corporation":false,"usgs":true,"family":"Hurst","given":"E.","email":"","affiliations":[],"preferred":false,"id":399754,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70023149,"text":"70023149 - 2001 - Ancient drainage basin of the Tharsis region, Mars: Potential source for outflow channel systems and putative oceans or paleolakes","interactions":[],"lastModifiedDate":"2022-12-02T18:06:44.713397","indexId":"70023149","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","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":"Ancient drainage basin of the Tharsis region, Mars: Potential source for outflow channel systems and putative oceans or paleolakes","docAbstract":"Paleotopographic reconstructions based on a synthesis of published geologic information and high-resolution topography, including topographic profiles, reveal the potential existence of an enormous drainage basin/aquifer system in the eastern part of the Tharsis region during the Noachian Period. Large topographic highs formed the margin of the gigantic drainage basin. Subsequently, lavas, sediments, and volatiles partly infilled the basin, resulting in an enormous and productive regional aquifer. The stacked sequences of water-bearing strata were then deformed locally and, in places, exposed by magmatic-driven uplifts, tectonic deformation, and erosion. This basin model provides a potential source of water necessary to carve the large outflow channel systems of the Tharsis and surrounding regions and to contribute to the formation of putative northern-plains ocean(s) and/or paleolakes.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000JE001468","issn":"01480227","usgsCitation":"Dohm, J.M., Ferris, J., Baker, V., Anderson, R.C., Hare, T., Strom, R., Barlow, N., Tanaka, K.L., Klemaszewski, J., and Scott, D.H., 2001, Ancient drainage basin of the Tharsis region, Mars: Potential source for outflow channel systems and putative oceans or paleolakes: Journal of Geophysical Research E: Planets, v. 106, no. E12, p. 32943-32958, https://doi.org/10.1029/2000JE001468.","productDescription":"16 p.","startPage":"32943","endPage":"32958","costCenters":[],"links":[{"id":501043,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://stars.library.ucf.edu/facultybib2000/7973","text":"External Repository"},{"id":233737,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Mars, Tharsis Region","volume":"106","issue":"E12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ebf5e4b0c8380cd48fc6","contributors":{"authors":[{"text":"Dohm, J. M.","contributorId":102150,"corporation":false,"usgs":true,"family":"Dohm","given":"J.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":396500,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ferris, J.C.","contributorId":13731,"corporation":false,"usgs":true,"family":"Ferris","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":396493,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Baker, V.R.","contributorId":47079,"corporation":false,"usgs":true,"family":"Baker","given":"V.R.","email":"","affiliations":[],"preferred":false,"id":396497,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Anderson, R. C.","contributorId":9755,"corporation":false,"usgs":true,"family":"Anderson","given":"R.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":396492,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Hare, T.M. 0000-0001-8842-389X","orcid":"https://orcid.org/0000-0001-8842-389X","contributorId":43828,"corporation":false,"usgs":true,"family":"Hare","given":"T.M.","affiliations":[],"preferred":false,"id":396495,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Strom, R.G.","contributorId":45744,"corporation":false,"usgs":true,"family":"Strom","given":"R.G.","email":"","affiliations":[],"preferred":false,"id":396496,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Barlow, N.G.","contributorId":107466,"corporation":false,"usgs":true,"family":"Barlow","given":"N.G.","email":"","affiliations":[],"preferred":false,"id":396501,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Tanaka, K. L.","contributorId":31394,"corporation":false,"usgs":false,"family":"Tanaka","given":"K.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":396494,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Klemaszewski, J.E.","contributorId":88102,"corporation":false,"usgs":true,"family":"Klemaszewski","given":"J.E.","email":"","affiliations":[],"preferred":false,"id":396499,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Scott, D. H.","contributorId":73565,"corporation":false,"usgs":true,"family":"Scott","given":"D.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":396498,"contributorType":{"id":1,"text":"Authors"},"rank":10}]}} ,{"id":70022732,"text":"70022732 - 2001 - Moss and lichen cover mapping at local and regional scales in the boreal forest ecosystem of central Canada","interactions":[],"lastModifiedDate":"2015-08-27T13:46:24","indexId":"70022732","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","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":"Moss and lichen cover mapping at local and regional scales in the boreal forest ecosystem of central Canada","docAbstract":"Mosses and lichens are important components of boreal landscapes [Vitt et al., 1994; Bubier et al., 1997]. They affect plant productivity and belowground carbon sequestration and alter the surface runoff and energy balance. We report the use of multiresolution satellite data to map moss and lichens over the BOREAS region at a 10 m, 30 m, and 1 km scales. Our moss and lichen classification at the 10 m scale is based on ground observations of associations among soil drainage classes, overstory composition, and cover type among four broad classes of ground cover (feather, sphagnum, and brown mosses and lichens). For our 30 m map, we used field observations of ground cover-overstory associations to map mosses and lichens in the BOREAS southern study area (SSA). To scale up to a 1 km (AVHRR) moss map of the BOREAS region, we used the TM SSA mosaics plus regional field data to identify AVHRR overstory-ground cover associations. We found that: 1) ground cover, overstory composition and density are highly correlated, permitting inference of moss and lichen cover from satellite-based land cover classifications; 2) our 1 km moss map reveals that mosses dominate the boreal landscape of central Canada, thereby a significant factor for water, energy, and carbon modeling; 3) TM and AVHRR moss cover maps are comparable; 4) satellite data resolution is important; particularly in detecting the smaller wetland features, lakes, and upland jack pine sites; and 5) distinct regional patterns of moss and lichen cover correspond to latitudinal and elevational gradients. Copyright 2001 by the American Geophysical Union.
","language":"English","publisher":"Wiley","doi":"10.1029/2001JD000509","issn":"01480227","usgsCitation":"Rapalee, G., Steyaert, L.T., and Hall, F., 2001, Moss and lichen cover mapping at local and regional scales in the boreal forest ecosystem of central Canada: Journal of Geophysical Research D: Atmospheres, v. 106, no. D24, p. 33551-33563, https://doi.org/10.1029/2001JD000509.","startPage":"33551","endPage":"33563","numberOfPages":"13","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":222,"text":"Earth Resources Observation and Science (EROS) Center","active":true,"usgs":true}],"links":[{"id":487430,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2001jd000509","text":"Publisher Index Page"},{"id":233566,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"106","issue":"D24","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5e88e4b0c8380cd70ad5","contributors":{"authors":[{"text":"Rapalee, G.","contributorId":35904,"corporation":false,"usgs":true,"family":"Rapalee","given":"G.","email":"","affiliations":[],"preferred":false,"id":394695,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Steyaert, L. T.","contributorId":71303,"corporation":false,"usgs":true,"family":"Steyaert","given":"L.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":394697,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hall, F.G.","contributorId":47099,"corporation":false,"usgs":true,"family":"Hall","given":"F.G.","email":"","affiliations":[],"preferred":false,"id":394696,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70023143,"text":"70023143 - 2001 - The roughness of natural terrain: A planetary and remote sensing perspective","interactions":[],"lastModifiedDate":"2019-02-18T08:35:53","indexId":"70023143","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","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":"The roughness of natural terrain: A planetary and remote sensing perspective","docAbstract":"We examine the various methods and parameters in common use for quantifying and reporting surface topographic \"roughness.\" It is shown that scale-dependent roughness parameters are almost always required, though not widely used. We suggest a method of standardizing the parameters that are computed and reported so that topographic data gathered by different workers using different field techniques can be directly and easily intercompared. We illustrate the proposed method by analyzing topographic data from 60 different surfaces gathered by five different groups and examine the information for common features. We briefly discuss the implications of our analysis for studies of planetary surface roughness, lander safety, and radar remote sensing modeling and analysis.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Geophysical Research E: Planets","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"American Geophysical Union","publisherLocation":"Washington, D.C.","doi":"10.1029/2000JE001429","issn":"01480227","usgsCitation":"Shepard, M.K., Campbell, B.A., Bulmer, M.H., Gaddis, L.R., Farr, T.G., and Plaut, J.J., 2001, The roughness of natural terrain: A planetary and remote sensing perspective: Journal of Geophysical Research E: Planets, v. 106, no. E12, p. 32777-32795, https://doi.org/10.1029/2000JE001429.","productDescription":"19 p.","startPage":"32777","endPage":"32795","numberOfPages":"19","costCenters":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"links":[{"id":478912,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2000je001429","text":"Publisher Index Page"},{"id":233664,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"106","issue":"E12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bafabe4b08c986b324977","contributors":{"authors":[{"text":"Shepard, Michael K.","contributorId":200622,"corporation":false,"usgs":false,"family":"Shepard","given":"Michael","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":396463,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Campbell, Bruce A.","contributorId":39813,"corporation":false,"usgs":true,"family":"Campbell","given":"Bruce","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":396465,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bulmer, Mark H.","contributorId":213328,"corporation":false,"usgs":false,"family":"Bulmer","given":"Mark","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":396467,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Gaddis, Lisa R. 0000-0001-9953-5483 lgaddis@usgs.gov","orcid":"https://orcid.org/0000-0001-9953-5483","contributorId":2817,"corporation":false,"usgs":true,"family":"Gaddis","given":"Lisa","email":"lgaddis@usgs.gov","middleInitial":"R.","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":true,"id":396466,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Farr, Tom G.","contributorId":213329,"corporation":false,"usgs":false,"family":"Farr","given":"Tom","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":396464,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Plaut, Jeffrey J.","contributorId":63516,"corporation":false,"usgs":true,"family":"Plaut","given":"Jeffrey","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":396462,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70023119,"text":"70023119 - 2001 - Mountains on Io: High-resolution Galileo observations, initial interpretations, and formation models","interactions":[],"lastModifiedDate":"2022-12-01T17:37:05.095565","indexId":"70023119","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","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":"Mountains on Io: High-resolution Galileo observations, initial interpretations, and formation models","docAbstract":"During three close flybys in late 1999 and early 2000 the Galileo spacecraft acquired new observations of the mountains that tower above Io's surface. These images have revealed surprising variety in the mountains' morphologies. They range from jagged peaks several kilometers high to lower, rounded structures. Some are very smooth, others are covered by numerous parallel ridges. Many mountains have margins that are collapsing outward in large landslides or series of slump blocks, but a few have steep, scalloped scarps. From these observations we can gain insight into the structure and material properties of Io's crust as well as into the erosional processes acting on Io. We have also investigated formation mechanisms proposed for these structures using finite-element analysis. Mountain formation might be initiated by global compression due to the high rate of global subsidence associated with Io's high resurfacing rate; however, our models demonstrate that this hypothesis lacks a mechanism for isolating the mountains. The large fraction (∼40%) of mountains that are associated with paterae suggests that in some cases these features are tectonically related. Therefore we have also simulated the stresses induced in Io's crust by a combination of a thermal upwelling in the mantle with global lithospheric compression and have shown that this can focus compressional stresses. If this mechanism is responsible for some of Io's mountains, it could also explain the common association of mountains with paterae.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000JE001354","issn":"01480227","usgsCitation":"Turtle, E.P., Jaeger, W.L., Keszthelyi, L., McEwen, A.S., Milazzo, M.P., Moore, J., Phillips, C.B., Radebaugh, J., Simonelli, D.P., Schuster, P., and Galileo SSI Team, 2001, Mountains on Io: High-resolution Galileo observations, initial interpretations, and formation models: Journal of Geophysical Research E: Planets, v. 106, no. E12, p. 33175-33199, https://doi.org/10.1029/2000JE001354.","productDescription":"25 p.","startPage":"33175","endPage":"33199","costCenters":[],"links":[{"id":233914,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Io","volume":"106","issue":"E12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5ebbe4b0c8380cd70c3c","contributors":{"authors":[{"text":"Turtle, Elizabeth P.","contributorId":45443,"corporation":false,"usgs":false,"family":"Turtle","given":"Elizabeth","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":396277,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jaeger, Windy L.","contributorId":61679,"corporation":false,"usgs":true,"family":"Jaeger","given":"Windy","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":396297,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Keszthelyi, Laszlo P. 0000-0003-1879-4331 laz@usgs.gov","orcid":"https://orcid.org/0000-0003-1879-4331","contributorId":52802,"corporation":false,"usgs":true,"family":"Keszthelyi","given":"Laszlo P.","email":"laz@usgs.gov","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":true,"id":396231,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"McEwen, Alfred S.","contributorId":61657,"corporation":false,"usgs":false,"family":"McEwen","given":"Alfred","email":"","middleInitial":"S.","affiliations":[{"id":7042,"text":"University of Arizona","active":true,"usgs":false}],"preferred":false,"id":396232,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Milazzo, Moses P. 0000-0002-9101-2191 moses@usgs.gov","orcid":"https://orcid.org/0000-0002-9101-2191","contributorId":4811,"corporation":false,"usgs":true,"family":"Milazzo","given":"Moses","email":"moses@usgs.gov","middleInitial":"P.","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":true,"id":396319,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Moore, Jeff","contributorId":49059,"corporation":false,"usgs":true,"family":"Moore","given":"Jeff","email":"","affiliations":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"preferred":false,"id":396284,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Phillips, Cynthia B.","contributorId":210488,"corporation":false,"usgs":false,"family":"Phillips","given":"Cynthia","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":396365,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Radebaugh, Jani","contributorId":101792,"corporation":false,"usgs":true,"family":"Radebaugh","given":"Jani","email":"","affiliations":[],"preferred":false,"id":396260,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Simonelli, Damon P.","contributorId":210484,"corporation":false,"usgs":false,"family":"Simonelli","given":"Damon","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":396271,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Schuster, Peter","contributorId":61607,"corporation":false,"usgs":true,"family":"Schuster","given":"Peter","email":"","affiliations":[],"preferred":false,"id":396261,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Galileo SSI Team","contributorId":299582,"corporation":true,"usgs":false,"organization":"Galileo SSI Team","id":858120,"contributorType":{"id":1,"text":"Authors"},"rank":11}]}} ,{"id":70023092,"text":"70023092 - 2001 - P-wave velocity structure of the uppermost mantle beneath Hawaii from traveltime tomography","interactions":[],"lastModifiedDate":"2012-03-12T17:20:07","indexId":"70023092","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1803,"text":"Geophysical Journal International","active":true,"publicationSubtype":{"id":10}},"title":"P-wave velocity structure of the uppermost mantle beneath Hawaii from traveltime tomography","docAbstract":"We examine the P-wave velocity structure beneath the island of Hawaii using P-wave residuals from teleseismic earthquakes recorded by the Hawaiian Volcano Observatory seismic network. The station geometry and distribution of events makes it possible to image the velocity structure between ~ 40 and 100 km depth with a lateral resolution of ~ 15 km and a vertical resolution of ~ 30 km. For depths between 40 and 80 km, P-wave velocities are up to 5 per cent slower in a broad elongated region trending SE-NW that underlies the island between the two lines defined by the volcanic loci. No direct correlation between the magnitude of the lithospheric anomaly and the current level of volcanic activity is apparent, but the slow region is broadened at ~ 19.8??N and narrow beneath Kilauea. In the case of the occanic lithosphere beneath Hawaii, slow seismic velocities are likely to be related to magma transport from the top of the melting zone at the base of the lithosphere to the surface. Thermal modelling shows that the broad elongated low-velocity zone cannot be explained in terms of conductive heating by one primary conduit per volcano but that more complicated melt pathways must exist.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geophysical Journal International","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1046/j.1365-246X.2001.00480.x","issn":"0956540X","usgsCitation":"Tilmann, F., Benz, H., Priestley, K., and Okubo, P.G., 2001, P-wave velocity structure of the uppermost mantle beneath Hawaii from traveltime tomography: Geophysical Journal International, v. 146, no. 3, p. 594-606, https://doi.org/10.1046/j.1365-246X.2001.00480.x.","startPage":"594","endPage":"606","numberOfPages":"13","costCenters":[],"links":[{"id":478946,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1046/j.1365-246x.2001.00480.x","text":"Publisher Index Page"},{"id":208055,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1046/j.1365-246X.2001.00480.x"},{"id":233440,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"146","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a731be4b0c8380cd76e73","contributors":{"authors":[{"text":"Tilmann, F.J.","contributorId":75305,"corporation":false,"usgs":true,"family":"Tilmann","given":"F.J.","email":"","affiliations":[],"preferred":false,"id":396147,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Benz, H.M.","contributorId":21594,"corporation":false,"usgs":true,"family":"Benz","given":"H.M.","email":"","affiliations":[],"preferred":false,"id":396145,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Priestley, K.F.","contributorId":64426,"corporation":false,"usgs":true,"family":"Priestley","given":"K.F.","email":"","affiliations":[],"preferred":false,"id":396146,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Okubo, P. 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Land disturbed by mining, however, has only recently been the focus of rehabilitation efforts. This research assesses the success of rehabilitation plans used to revegetate gypsum mine spoils within the environmental constraints of the north-west Indian hot-desert ecosystem. The rehabilitation plan first examined both mined and unmined areas and established assessments of existing vegetative cover and the quality of native soils and mine spoils. Tests were made on the effect of the use, and conservation, of available water through rainwater harvesting, amendment application (for physical and chemical spoil modification), plant establishment protocols, and the selection of appropriate germ plasm. Our results show that the resulting vegetative cover is capable of perpetuating itself under natural conditions while concurrently meeting the needs of farmers. Although the mine spoils are deficient in organic matter and phosphorus, they possess adequate amounts of all other nutrients. Total boron concentrations (>5.0 mg kg-1) in both the topsail and mine spoil indicate potentially phytotoxic conditions. Electrical conductance of mine spoil is 6-10 times higher than for topsail with a near-neutral pH. Populations of spoil fungi, Azotobactor, and nitrifying bacteria are low. The soil moisture storage in rainwater harvesting plots increased by 8% over the control and 48% over the unmined area. As a result of rehabilitation efforts, mine spoils show a steady buildup in organic carbon, and P and K due to the decomposition of farmyard manure and the contribution of nitrogen fixation by the established leguminous plant species. The rehabilitation protocol used at the site appears to have been successful. Following revegetation of the area with a mixture of trees, shrubs, and grasses, native implanted species have become established. Species diversity, measured in terms of species richness, increased after one year and then gradually declined over time; the decline was the result of the loss of annual species. The study not only develops methods of gypsum mine land rehabilitation but also helps in understanding processes of rehabilitation success in arid regions and emphasizes the importance of long-term monitoring of rehabilitation success. Copyright ?? 2001 Taylor & Francis.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Arid Soil Research and Rehabilitation","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1080/15324980119929","issn":"08903069","usgsCitation":"Sharma, K., Kumar, S., and Gough, L.P., 2001, Rehabilitation of gypsum-mined lands in the Indian desert: Arid Soil Research and Rehabilitation, v. 15, no. 1, p. 61-76, https://doi.org/10.1080/15324980119929.","startPage":"61","endPage":"76","numberOfPages":"16","costCenters":[],"links":[{"id":233487,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":265777,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1080/15324980119929"}],"volume":"15","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"50e4a601e4b0e8fec6cdc063","contributors":{"authors":[{"text":"Sharma, K.D.","contributorId":53545,"corporation":false,"usgs":true,"family":"Sharma","given":"K.D.","email":"","affiliations":[],"preferred":false,"id":394681,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kumar, S.","contributorId":89843,"corporation":false,"usgs":true,"family":"Kumar","given":"S.","affiliations":[],"preferred":false,"id":394683,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gough, L. P.","contributorId":64198,"corporation":false,"usgs":true,"family":"Gough","given":"L.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":394682,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70023087,"text":"70023087 - 2001 - Choosing between atmospheric pressure chemical ionization and electrospray ionization interfaces for the HPLC/MS analysis of pesticides","interactions":[],"lastModifiedDate":"2018-11-30T06:52:10","indexId":"70023087","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":761,"text":"Analytical Chemistry","active":true,"publicationSubtype":{"id":10}},"title":"Choosing between atmospheric pressure chemical ionization and electrospray ionization interfaces for the HPLC/MS analysis of pesticides","docAbstract":"An evaluation of over 75 pesticides by high-performance liquid chromatography/mass spectrometry (HPLC/MS) clearly shows that different classes of pesticides are more sensitive using either atmospheric pressure chemical ionization (APCI) or electrospray ionization (ESI). For example, neutral and basic pesticides (phenylureas, triazines) are more sensitive using APCI (especially positive ion). While cationic and anionic herbicides (bipyridylium ions, sulfonic acids) are more sensitive using ESI (especially negative ion). These data are expressed graphically in a figure called an ionization-continuum diagram, which shows that protonation in the gas phase (proton affinity) and polarity in solution, expressed as proton addition or subtraction (pKa), is useful in selecting APCI or ESI. Furthermore, sodium adduct formation commonly occurs using positive ion ESI but not using positive ion APCI, which reflects the different mechanisms of ionization and strengthens the usefulness of the ionization-continuum diagram. The data also show that the concept of \"wrong-way around\" ESI (the sensitivity of acidic pesticides in an acidic mobile phase) is a useful modification of simple pKa theory for mobile-phase selection. Finally, this finding is used to enhance the chromatographic separation of oxanilic and sulfonic acid herbicides while maintaining good sensitivity in LC/MS using ESI negative.","language":"English","doi":"10.1021/ac010506f","issn":"00032700","usgsCitation":"Thurman, E., Ferrer, I., and Barcelo, D., 2001, Choosing between atmospheric pressure chemical ionization and electrospray ionization interfaces for the HPLC/MS analysis of pesticides: Analytical Chemistry, v. 73, no. 22, p. 5441-5449, https://doi.org/10.1021/ac010506f.","productDescription":"9 p.","startPage":"5441","endPage":"5449","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":233370,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":208016,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/ac010506f"}],"volume":"73","issue":"22","noUsgsAuthors":false,"publicationDate":"2001-10-09","publicationStatus":"PW","scienceBaseUri":"5059f5d7e4b0c8380cd4c45e","contributors":{"authors":[{"text":"Thurman, E.M.","contributorId":102864,"corporation":false,"usgs":true,"family":"Thurman","given":"E.M.","affiliations":[],"preferred":false,"id":396089,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ferrer, I.","contributorId":97260,"corporation":false,"usgs":true,"family":"Ferrer","given":"I.","email":"","affiliations":[],"preferred":false,"id":396088,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Barcelo, D.","contributorId":24107,"corporation":false,"usgs":true,"family":"Barcelo","given":"D.","affiliations":[],"preferred":false,"id":396087,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024008,"text":"70024008 - 2001 - Remarks on the travelling wave decomposition","interactions":[],"lastModifiedDate":"2012-03-12T17:20:19","indexId":"70024008","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1803,"text":"Geophysical Journal International","active":true,"publicationSubtype":{"id":10}},"title":"Remarks on the travelling wave decomposition","docAbstract":"In elastic wave propagation on a spherically symmetric earth model, a normal mode sum is converted into a sum of equivalent travelling waves by means of a travelling wave decomposition (TWD). For two decades, seismologists have assumed that each travelling wave in the TWD is associated with only real phase velocities, that is, no evanescent waves travel on a spherically symmetric earth model. In this paper, this assumption is proven false. By including a countably infinite set of waves travelling as evanescent waves, several conceptual difficulties confronting the TWD are resolved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geophysical Journal International","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1046/j.1365-246X.2001.00271.x","issn":"0956540X","usgsCitation":"Pollitz, F., 2001, Remarks on the travelling wave decomposition: Geophysical Journal International, v. 144, no. 2, p. 233-246, https://doi.org/10.1046/j.1365-246X.2001.00271.x.","startPage":"233","endPage":"246","numberOfPages":"14","costCenters":[],"links":[{"id":487340,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1046/j.1365-246x.2001.00271.x","text":"Publisher Index Page"},{"id":231672,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":207077,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1046/j.1365-246X.2001.00271.x"}],"volume":"144","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505aa6cce4b0c8380cd85067","contributors":{"authors":[{"text":"Pollitz, F. F.","contributorId":108280,"corporation":false,"usgs":true,"family":"Pollitz","given":"F. F.","affiliations":[],"preferred":false,"id":399672,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70023086,"text":"70023086 - 2001 - Geologic structures related to New Madrid earthquakes near Memphis, Tennessee, based on gravity and magnetic interpretations","interactions":[],"lastModifiedDate":"2012-03-12T17:20:08","indexId":"70023086","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1517,"text":"Engineering Geology","active":true,"publicationSubtype":{"id":10}},"title":"Geologic structures related to New Madrid earthquakes near Memphis, Tennessee, based on gravity and magnetic interpretations","docAbstract":"New inversions of gravity and magnetic data in the region north of memphis. Tennessee, and south of latitude 36?? define boundaries of regional structures and igneous complexes in the upper crust. Microseismicity patterns near interpreted boundaries suggest that igneous complexes influence the locations of microseismicity. A weak seismicity cluster occurs near one intrusion (Covington pluton), at the intersection of the southwest margin of the Missouri batholith and the southeast margin of the Reelfoot rift. A narrow seismicity trend along the Reelfoot rift axis becomes diffuse near a second intrusion (Osceola intrusive complex) and changes direction to an area along the northwest flank of the intrusion. The axial seismicity trend also contains a tight cluster of earthquakes located just outside the Osceola intrusive complex. The mechanical explanation of the two seismicity patterns is uncertain, but the first cluster may be caused by stress concentration due to the high elastic stiffness and strength of the Covington intrusion. The spatially changing seismicity pattern near the Osceola complex may be caused by the preceding factors plus interaction with faulting along the rift axis. The axial seismicity strand itself is one of several connected and interacting active strands that may produce stress concentrations at strand ends and junctions. The microseismicity clusters at the peripheries of the two intrusions lead us to conclude that these stress concentrations or stressed volumes may be locations of future moderate to large earthquakes near Memphis. Published by Elsevier Science B.V.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Engineering Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0013-7952(01)00056-4","issn":"00137952","usgsCitation":"Hildenbrand, T., Stuart, W., and Talwani, P., 2001, Geologic structures related to New Madrid earthquakes near Memphis, Tennessee, based on gravity and magnetic interpretations: Engineering Geology, v. 62, no. 1-3, p. 105-121, https://doi.org/10.1016/S0013-7952(01)00056-4.","startPage":"105","endPage":"121","numberOfPages":"17","costCenters":[],"links":[{"id":208015,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0013-7952(01)00056-4"},{"id":233369,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"62","issue":"1-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a21eee4b0c8380cd56bf6","contributors":{"authors":[{"text":"Hildenbrand, T.G.","contributorId":83892,"corporation":false,"usgs":true,"family":"Hildenbrand","given":"T.G.","email":"","affiliations":[],"preferred":false,"id":396085,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Stuart, W.D.","contributorId":65865,"corporation":false,"usgs":true,"family":"Stuart","given":"W.D.","email":"","affiliations":[],"preferred":false,"id":396084,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Talwani, P.","contributorId":101420,"corporation":false,"usgs":true,"family":"Talwani","given":"P.","affiliations":[],"preferred":false,"id":396086,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70023085,"text":"70023085 - 2001 - Comparisons of ground motions from the 1999 Chi-Chi, earthquake with empirical predictions largely based on data from California","interactions":[],"lastModifiedDate":"2012-03-12T17:20:40","indexId":"70023085","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1135,"text":"Bulletin of the Seismological Society of America","onlineIssn":"1943-3573","printIssn":"0037-1106","active":true,"publicationSubtype":{"id":10}},"title":"Comparisons of ground motions from the 1999 Chi-Chi, earthquake with empirical predictions largely based on data from California","docAbstract":"This article has the modest goal of comparing the ground motions recorded during the 1999 Chi-Chi, Taiwan, mainshock with predictions from four empirical-based equations commonly used for western North America; these empirical predictions are largely based on data from California. Comparisons are made for peak acceleration and 5%-damped response spectra at periods between 0.1 and 4 sec. The general finding is that the Chi-Chi ground motions are smaller than those predicted from the empirically based equations for periods less than about 1 sec by factors averaging about 0.4 but as small as 0.26 (depending on period, on which equation is used, and on whether the sites are assumed to be rock or soil). There is a trend for the observed motions to approach or even exceed the predicted motions for longer periods. Motions at similar distances (30-60 km) to the east and to the west of the fault differ dramatically at periods between about 2 and 20 sec: Long-duration wave trains are present on the motions to the west, and when normalized to similar amplitudes at short periods, the response spectra of the motions at the western stations are as much as five times larger than those of motions from eastern stations. The explanation for the difference is probably related to site and propagation effects; the western stations are on the Coastal Plain, whereas the eastern stations are at the foot of young and steep mountains, either in the relatively narrow Longitudinal Valley or along the eastern coast-the sediments underlying the eastern stations are probably shallower and have higher velocity than those under the western stations.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Bulletin of the Seismological Society of America","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1785/0120000733","issn":"00371106","usgsCitation":"Boore, D., 2001, Comparisons of ground motions from the 1999 Chi-Chi, earthquake with empirical predictions largely based on data from California: Bulletin of the Seismological Society of America, v. 91, no. 5, p. 1212-1217, https://doi.org/10.1785/0120000733.","startPage":"1212","endPage":"1217","numberOfPages":"6","costCenters":[],"links":[{"id":233913,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":208278,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1785/0120000733"}],"volume":"91","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f8c2e4b0c8380cd4d2a2","contributors":{"authors":[{"text":"Boore, D.M. 0000-0002-8605-9673","orcid":"https://orcid.org/0000-0002-8605-9673","contributorId":64226,"corporation":false,"usgs":true,"family":"Boore","given":"D.M.","affiliations":[],"preferred":false,"id":396083,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70023998,"text":"70023998 - 2001 - Differential rates of feldspar weathering in granitic regoliths","interactions":[],"lastModifiedDate":"2012-03-12T17:20:19","indexId":"70023998","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","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":"Differential rates of feldspar weathering in granitic regoliths","docAbstract":"Differential rates of plagioclase and K-feldspar weathering commonly observed in bedrock and soil environments are examined in terms of chemical kinetic and solubility controls and hydrologic permeability. For the Panola regolith, in the Georgia Piedmont Province of southeastern United States, petrographic observations, coupled with elemental balances and 87Sr/86Sr ratios, indicate that plagioclase is being converted to kaolinite at depths > 6 m in the granitic bedrock. K-feldspar remains pristine in the bedrock but subsequently weathers to kaolinite at the overlying saprolite. In contrast, both plagioclase and K-feldspar remain stable in granitic bedrocks elsewhere in Piedmont Province, such as Davis Run, Virginia, where feldspars weather concurrently in an overlying thick saprolite sequence. Kinetic rate constants, mineral surface areas, and secondary hydraulic conductivities are fitted to feldspar losses with depth in the Panola and Davis Run regoliths using a time-depth computer spreadsheet model. The primary hydraulic conductivities, describing the rates of meteoric water penetration into the pristine granites, are assumed to be equal to the propagation rates of weathering fronts, which, based on cosmogenic isotope dating, are 7 m/106 yr for the Panola regolith and 4 m/106 yr for the Davis Run regolith. Best fits in the calculations indicate that the kinetic rate constants for plagioclase in both regoliths are factors of two to three times faster than K-feldspar, which is in agreement with experimental findings. However, the range for plagioclase and K-feldspar rates (kr = 1.5 x 10-17 to 2.8 x 10-16 mol m-2 s-1) is three to four orders of magnitude lower than for that for experimental feldspar dissolution rates and are among the slowest yet recorded for natural feldspar weathering. Such slow rates are attributed to the relatively old geomorphic ages of the Panola and Davis Run regoliths, implying that mineral surface reactivity decreases significantly with time. Differential feldspar weathering in the low-permeability Panola bedrock environment is more dependent on relative feldspar solubilities than on differences in kinetic reaction rates. Such weathering is very sensitive to primary and secondary hydraulic conductivities (qp and qs), which control both the fluid volumes passing through the regolith and the thermodynamic saturation of the feldspars. Bedrock permeability is primarily intragranular and is created by internal weathering of networks of interconnected plagioclase phenocrysts. Saprolite permeability is principally intergranular and is the result of dissolution of silicate phases during isovolumetric weathering. A secondary to primary hydraulic conductivity ratio of qs/qp = 150 in the Panola bedrock results in kinetically controlled plagioclase dissolution but thermodynamically inhibited K-feldspar reaction. This result is in accord with calculated chemical saturation states for groundwater sampled in the Panola Granite. In contrast, greater secondary conductivities in the Davis Run saprolite, qs/qp = 800, produces both kinetically controlled plagioclase and K-feldspar dissolution. Faster plagioclase reaction, leading to bedrock weathering in the Panola Granite but not at Davis Run, is attributed to a higher anorthite component of the plagioclase and a wetter and warmer climate. In addition, the Panola Granite has an abnormally high content of disseminated calcite, the dissolution of which precedes the plagioclase weathering front, thus creating additional secondary permeability. Copyright ?? 2001 Elsevier Science Ltd.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geochimica et Cosmochimica Acta","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0016-7037(00)00577-9","issn":"00167037","usgsCitation":"White, A.F., Bullen, T., Schulz, M.S., Blum, A., Huntington, T., and Peters, N., 2001, Differential rates of feldspar weathering in granitic regoliths: Geochimica et Cosmochimica Acta, v. 65, no. 6, p. 847-869, https://doi.org/10.1016/S0016-7037(00)00577-9.","startPage":"847","endPage":"869","numberOfPages":"23","costCenters":[],"links":[{"id":231522,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206996,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0016-7037(00)00577-9"}],"volume":"65","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a00ffe4b0c8380cd4fa30","contributors":{"authors":[{"text":"White, A. F.","contributorId":36546,"corporation":false,"usgs":true,"family":"White","given":"A.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":399634,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bullen, T.D.","contributorId":79911,"corporation":false,"usgs":true,"family":"Bullen","given":"T.D.","email":"","affiliations":[],"preferred":false,"id":399636,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Schulz, M. S.","contributorId":7299,"corporation":false,"usgs":true,"family":"Schulz","given":"M.","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":399632,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Blum, A.E.","contributorId":100514,"corporation":false,"usgs":true,"family":"Blum","given":"A.E.","email":"","affiliations":[],"preferred":false,"id":399637,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Huntington, T.G. 0000-0002-9427-3530","orcid":"https://orcid.org/0000-0002-9427-3530","contributorId":64675,"corporation":false,"usgs":true,"family":"Huntington","given":"T.G.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":false,"id":399635,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Peters, N.E.","contributorId":33332,"corporation":false,"usgs":true,"family":"Peters","given":"N.E.","email":"","affiliations":[],"preferred":false,"id":399633,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70023994,"text":"70023994 - 2001 - Crocoite: An unusual mode of occurrence for lead in coal","interactions":[],"lastModifiedDate":"2019-06-05T10:26:07","indexId":"70023994","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2033,"text":"International Journal of Coal Geology","active":true,"publicationSubtype":{"id":10}},"title":"Crocoite: An unusual mode of occurrence for lead in coal","docAbstract":"What is believed to be a very unusual mode of occurrence for lead in coal has been identified as crocoite (PbCrO4). As part of a larger study on trace elements and mineralogy in the Cretaceous Main Seam in New Zealand, crocoite was found in raw coal samples within the lower part of the coal seam. X-ray diffraction (XRD) and bulk chemical data from a SEM equipped with an energy dispersive X-ray analyser (EDXA) have confirmed the identity of this mineral. This is apparently the first time that crocoite has been reported in coal. Crocoite usually occurs only in the oxidised zone of lead mineral deposits. The occurrence of this mineral in the Main Seam coal implies that the deposit was exposed to an oxidising environment at some stage, most likely after coalification. Published by Elsevier Science B.V.","language":"English","publisher":"Elsevier","doi":"10.1016/S0166-5162(00)00024-0","issn":"01665162","usgsCitation":"Li, Z., Moore, T., Weaver, S., and Finkelman, R.B., 2001, Crocoite: An unusual mode of occurrence for lead in coal: International Journal of Coal Geology, v. 45, no. 4, p. 289-293, https://doi.org/10.1016/S0166-5162(00)00024-0.","productDescription":"5 p.","startPage":"289","endPage":"293","numberOfPages":"5","costCenters":[],"links":[{"id":232094,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"45","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fcb6e4b0c8380cd4e3cd","contributors":{"authors":[{"text":"Li, Z.","contributorId":29160,"corporation":false,"usgs":true,"family":"Li","given":"Z.","affiliations":[],"preferred":false,"id":399623,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Moore, T.A.","contributorId":91101,"corporation":false,"usgs":true,"family":"Moore","given":"T.A.","email":"","affiliations":[],"preferred":false,"id":399624,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Weaver, S.D.","contributorId":20914,"corporation":false,"usgs":true,"family":"Weaver","given":"S.D.","email":"","affiliations":[],"preferred":false,"id":399622,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Finkelman, R. B.","contributorId":20341,"corporation":false,"usgs":true,"family":"Finkelman","given":"R.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":399621,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70023992,"text":"70023992 - 2001 - Simulation of stream discharge and transport of nitrate and selected herbicides in the Mississippi River Basin","interactions":[],"lastModifiedDate":"2012-03-12T17:20:02","indexId":"70023992","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1924,"text":"Hydrological Processes","active":true,"publicationSubtype":{"id":10}},"title":"Simulation of stream discharge and transport of nitrate and selected herbicides in the Mississippi River Basin","docAbstract":"Stream discharge and the transport of nitrate, atrazine, and metolachlor in the Mississippi River Basin were simulated using the DAFLOW/BLTM hydrologic model. The simulated domain for stream discharge included river reaches downstream from the following stations in the National Stream Quality Accounting Network: Mississippi River at Clinton, IA; Missouri River at Hermann, MO: Ohio River at Grand Chain, IL: And Arkansas River at Little Rock, AR. Coefficients of hydraulic geometry were calibrated using data from water year 1996; the model was validated by favourable simulation of observed discharges in water years 1992-1994. The transport of nitrate, atrazine, and metolachlor was simulated downstream from the Mississippi River at Thebes, IL, and the Ohio River at Grand Chain. Simulated concentrations compared favourably with observed concentrations at Baton Rouge, LA. Development of this model is a preliminary step in gaining a more quantitative understanding of the sources and fate of nutrients and pesticides delivered from the Mississippi River Basin to the Gulf of Mexico.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrological Processes","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1002/hyp.208","issn":"08856087","usgsCitation":"Broshears, R.E., Clark, G.M., and Jobson, H., 2001, Simulation of stream discharge and transport of nitrate and selected herbicides in the Mississippi River Basin: Hydrological Processes, v. 15, no. 7, p. 1157-1167, https://doi.org/10.1002/hyp.208.","startPage":"1157","endPage":"1167","numberOfPages":"11","costCenters":[],"links":[{"id":232057,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":207257,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1002/hyp.208"}],"volume":"15","issue":"7","noUsgsAuthors":false,"publicationDate":"2001-05-25","publicationStatus":"PW","scienceBaseUri":"505b908ae4b08c986b319577","contributors":{"authors":[{"text":"Broshears, R. E.","contributorId":75552,"corporation":false,"usgs":true,"family":"Broshears","given":"R.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":399617,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Clark, G. M.","contributorId":90325,"corporation":false,"usgs":true,"family":"Clark","given":"G.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":399618,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Jobson, H.E.","contributorId":44952,"corporation":false,"usgs":true,"family":"Jobson","given":"H.E.","affiliations":[],"preferred":false,"id":399616,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70023987,"text":"70023987 - 2001 - Distribution of oxygen-18 and deuteriun in river waters across the United States","interactions":[],"lastModifiedDate":"2018-11-30T05:24:24","indexId":"70023987","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1924,"text":"Hydrological Processes","active":true,"publicationSubtype":{"id":10}},"title":"Distribution of oxygen-18 and deuteriun in river waters across the United States","docAbstract":"Reconstruction of continental palaeoclimate and palaeohydrology is currently hampered by limited information about isotopic patterns in the modern hydrologic cycle. To remedy this situation and to provide baseline data for other isotope hydrology studies, more than 4800, depth- and width-integrated, stream samples from 391 selected sites within the USGS National Stream Quality Accounting Network (NASQAN) and Hydrologic Benchmark Network (HBN) were analysed for δ18O and δ2H (http://water.usgs.gov/pubs/ofr/ofr00-160/pdf/ofr00-160.pdf). Each site was sampled bimonthly or quarterly for 2·5 to 3 years between 1984 and 1987. The ability of this dataset to serve as a proxy for the isotopic composition of modern precipitation in the USA is supported by the excellent agreement between the river dataset and the isotopic compositions of adjacent precipitation monitoring sites, the strong spatial coherence of the distributions of δ18O and δ2H, the good correlations of the isotopic compositions with climatic parameters, and the good agreement between the ‘national’ meteoric water line (MWL) generated from unweighted analyses of samples from the 48 contiguous states of δ2H=8·11δ18O+8·99 (r2=0·98) and the unweighted global MWL of sites from the Global Network for Isotopes in Precipitation (GNIP) of the International Atomic Energy Agency and the World Meteorological Organization (WMO) of δ2H=8·17δ18O+10·35.
\nThe national MWL is composed of water samples that arise in diverse local conditions where the local meteoric water lines (LMWLs) usually have much lower slopes. Adjacent sites often have similar LMWLs, allowing the datasets to be combined into regional MWLs. The slopes of regional MWLs probably reflect the humidity of the local air mass, which imparts a distinctive evaporative isotopic signature to rainfall and hence to stream samples. Deuterium excess values range from 6 to 15‰ in the eastern half of the USA, along the northwest coast and on the Colorado Plateau. In the rest of the USA, these values range from −2 to 6‰, with strong spatial correlations with regional aridity. The river samples have successfully integrated the spatial variability in the meteorological cycle and provide the best available dataset on the spatial distributions of δ18O and δ2H values of meteoric waters in the USA.
\n