Accurate estimates of watershed denudation absent anthropogenic effects are required to develop strategies for mitigating accelerated physical erosion resulting from human activities, to model global geochemical cycles, and to examine interactions among climate, weathering, and uplift. We present a simple approach to estimate predevelopment denudation rates using in-situ-produced cosmogenic 10Be in fluvial sediments. Denudation processes in an agricultural watershed (Cayaguas River Basin, Puerto Rico) and a matched undisturbed watershed (Icacos River Basin) were compared using 10Be concentrations in quartz for various size fractions of bed material. The coarse fractions in both watersheds bear the imprint of long subsurface residence times. Fine material from old shallow soils contributes little, however, to the present-day sediment output of the Cayaguas. This confirms the recent and presumably anthropogenic origin of the modern high denudation rate in the Cayaguas Basin and suggests that pre-agricultural erosional conditions were comparable to those of the present-day Icacos.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Earth and Planetary Science Letters","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0012-821X(98)00123-X","issn":"0012821X","usgsCitation":"Brown, E., Stallard, R., Larsen, M.C., Bourles, D., Raisbeck, G., and Yiou, F., 1998, Determination of predevelopment denudation rates of an agricultural watershed (Cayaguas River, Puerto Rico) using in-situ-produced 10Be in river-borne quartz: Earth and Planetary Science Letters, v. 160, no. 3-4, p. 723-728, https://doi.org/10.1016/S0012-821X(98)00123-X.","productDescription":"6 p.","startPage":"723","endPage":"728","numberOfPages":"6","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":156,"text":"Caribbean Water Science Center","active":true,"usgs":true}],"links":[{"id":230234,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206565,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0012-821X(98)00123-X"}],"volume":"160","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ffbfe4b0c8380cd4f390","contributors":{"authors":[{"text":"Brown, E.T.","contributorId":6636,"corporation":false,"usgs":true,"family":"Brown","given":"E.T.","email":"","affiliations":[],"preferred":false,"id":387656,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Stallard, R.F.","contributorId":30247,"corporation":false,"usgs":true,"family":"Stallard","given":"R.F.","email":"","affiliations":[],"preferred":false,"id":387659,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Larsen, M. C.","contributorId":66287,"corporation":false,"usgs":true,"family":"Larsen","given":"M.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":387660,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Bourles, D.L.","contributorId":22630,"corporation":false,"usgs":true,"family":"Bourles","given":"D.L.","email":"","affiliations":[],"preferred":false,"id":387658,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Raisbeck, G.M.","contributorId":21031,"corporation":false,"usgs":true,"family":"Raisbeck","given":"G.M.","email":"","affiliations":[],"preferred":false,"id":387657,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Yiou, F.","contributorId":94829,"corporation":false,"usgs":true,"family":"Yiou","given":"F.","email":"","affiliations":[],"preferred":false,"id":387661,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70021129,"text":"70021129 - 1998 - Sedimentary facies and environmental ichnology of a ?Permian playa-lake complex in western Argentina","interactions":[],"lastModifiedDate":"2012-03-12T17:19:49","indexId":"70021129","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2996,"text":"Palaeogeography, Palaeoclimatology, Palaeoecology","printIssn":"0031-0182","active":true,"publicationSubtype":{"id":10}},"title":"Sedimentary facies and environmental ichnology of a ?Permian playa-lake complex in western Argentina","docAbstract":"A moderately diverse arthropod icnofauna occurs in ?Permian ephemeral lacustrine deposits of the Paganzo Basin that crop out at Bordo Atravesado, Cuesta de Miranda, western Argentina. Sedimentary successions are interpreted as having accumulated in a playa-lake complex. Deposits include three sedimentary facies: (A) laminated siltstone and mudstone: (B) current-rippled cross-laminated very fine grained sandstone: and (C) climbing and wave-rippled cross-laminated fine-grained sandstone deposited by sheet floods under wave influence in the playa-lake complex. Analysis of facies sequences suggests that repeated vertical facies associations result from transgressive regressive episodes of variable time spans. The Bordo Atravesado ichnofauna includes Cruziana problematica, Diplocraterion isp., cf. Diplopadichnus biformis, Kouphichnium? isp., Merostomichnites aicunai, Mirandaichnium famatinense, Monomorphichnus lineatus, Palaeophyeus tubularis, Umfolozia sinuosa and Umfolozia ef. U. longula. The assemblage is largely dominated by arthropod trackways and represents an example of the Scoyenia ichnofacies. Trace fossils are mostly preserved as hypichnial ridges on the soles of facies C beds, being comparatively rare in facies A and B. Ichnofossil preservation was linked to rapid influx of sand via sheet floods entering into the lake. Four taphonomic variants (types 1-4) are recognized, each determined by substrate consistency and time averaging. Type 1 is recorded by the presence of low density assemblages consisting of poorly defined trackways, which suggests that arthropods crawled in soft, probably slightly subaqueous substrates. Type 2 is represented by low to moderate density suites that include sharply defined trackways commonly associated with mud cracks, suggesting that the tracemakers inhabited a firm, desiccated lacustrine substrate. Type 3 displays features of types 1 and 2 and represents palimpsestic bedding surfaces, resulting from the overprint of terrestrial ichnocoenoses over previously formed softground suites. Type 4 differs from type 2 only in that assemblages display a high density of traces, recorded by numerous superimposed trackways, which suggests a major time gap of subaerial exposure before sheet flood entrance. Therefore, type 4 surfaces are mostly interpreted as track imprinted omission surfaces.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Palaeogeography, Palaeoclimatology, Palaeoecology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0031-0182(97)00116-8","issn":"00310182","usgsCitation":"Zhang, G., Buatois, L., Mangano, M., and Acenolaza, F., 1998, Sedimentary facies and environmental ichnology of a ?Permian playa-lake complex in western Argentina: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 138, no. 1-4, p. 221-243, https://doi.org/10.1016/S0031-0182(97)00116-8.","startPage":"221","endPage":"243","numberOfPages":"23","costCenters":[],"links":[{"id":206455,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0031-0182(97)00116-8"},{"id":229814,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"138","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8a20e4b08c986b31704d","contributors":{"authors":[{"text":"Zhang, G.","contributorId":12636,"corporation":false,"usgs":true,"family":"Zhang","given":"G.","email":"","affiliations":[],"preferred":false,"id":388750,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Buatois, L.A.","contributorId":40740,"corporation":false,"usgs":true,"family":"Buatois","given":"L.A.","affiliations":[],"preferred":false,"id":388751,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mangano, M.G.","contributorId":7432,"corporation":false,"usgs":true,"family":"Mangano","given":"M.G.","email":"","affiliations":[],"preferred":false,"id":388749,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Acenolaza, F.G.","contributorId":101836,"corporation":false,"usgs":true,"family":"Acenolaza","given":"F.G.","email":"","affiliations":[],"preferred":false,"id":388752,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70021125,"text":"70021125 - 1998 - The tectonic significance of pre-Scandian 40Ar/39Ar phengite cooling ages in the Caledonides of western Norway","interactions":[],"lastModifiedDate":"2024-05-14T15:49:51.570617","indexId":"70021125","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2545,"text":"Journal of the Geological Society","active":true,"publicationSubtype":{"id":10}},"displayTitle":"The tectonic significance of pre-Scandian 40Ar/39Ar phengite cooling ages in the Caledonides of western Norway","title":"The tectonic significance of pre-Scandian 40Ar/39Ar phengite cooling ages in the Caledonides of western Norway","docAbstract":"Pre-Silurian continental-margin deposits in western Norway, non-conformably overlying allochthonous continental orthogneisses retain Ordovician 40Ar/39Ar cooling ages for phengites, implying either rapid cooling immediately after a Late Ordovician orogenic event, or less likely, a slow cooling following an Early Ordovician or older orogeny. The Dalsfjord Suite–Høyvik Group basement–cover pair are probably a lateral equivalent to Late Proterozoic sandstones (‘sparagmites’) covering the Jotun Nappe gneisses of the Middle Allochthon in central-south Norway. The Høyvik Group underwent polyphase deformation, greenschist-facies metamorphism (Tmax<450°C) and exhumation prior to deposition of the unconformably overlying Wenlockian continental-margin deposits of the Herland Group. The Høyvik Group was only weakly metamorphosed during obduction of the Solund–Stavfjord Ophiolite and the Scandian continental collision between Baltica and Laurentia. Phengitic white micas from the Høyvik Group yield cooling ages of 446.1± 3.0, 449.1±2.2 and 447.5±4.0 Ma, respectively, identical within experimental error. One sample gives a plateau over 72% of the gas analysed, whereas the other samples were slightly disturbed after initial cooling, as indicated by systematically lower apparent ages at low experimental extraction temperatures. Minor 40Ar loss probably occurred during subsequent Scandian deformation and late to post-orogenic extension.The Høyvik Group rocks were unroofed before the Wenlock time (423–428 Ma) and cooled through the temperature for argon retention in phengite at c. 447±4 Ma, indicating a maximum cooling rate between 14 and 22C/Ma-1 through Ashgill and Llandovery times before being subjected to low-grade metamorphism during the Scandian orogeny. Rapid pre-Scandian cooling, combined with peak metamorphic conditions of 450C or less, may indicate that the Dalsfjord–Høyvik basement–cover pair were aVected by an orogenic event during the Late Ordovician (Caradoc) time. The data also suggest that the Caledonian margin of Baltica may have experienced a more protracted tectonism during the Caledonian cycle than previously models focusing on Early Caledonian and Tremadoc (or older) ophiolite obduction and the Scandian continental collision between Baltica and Laurentia.
","language":"English","publisher":"Geological Society of London","doi":"10.1144/gsjgs.155.2.0297","issn":"00167649","usgsCitation":"Andersen, T., Berry, H.N., Lux, D.R., and Andresen, A., 1998, The tectonic significance of pre-Scandian 40Ar/39Ar phengite cooling ages in the Caledonides of western Norway: Journal of the Geological Society, v. 155, no. 2, p. 297-309, https://doi.org/10.1144/gsjgs.155.2.0297.","productDescription":"13 p.","startPage":"297","endPage":"309","numberOfPages":"13","costCenters":[],"links":[{"id":229773,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"155","issue":"2","noUsgsAuthors":false,"publicationDate":"2022-06-06","publicationStatus":"PW","scienceBaseUri":"505bb0eae4b08c986b32511c","contributors":{"authors":[{"text":"Andersen, T.B.","contributorId":75715,"corporation":false,"usgs":true,"family":"Andersen","given":"T.B.","email":"","affiliations":[],"preferred":false,"id":388736,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Berry, H. N. IV","contributorId":99326,"corporation":false,"usgs":true,"family":"Berry","given":"H.","suffix":"IV","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":388737,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lux, D. R.","contributorId":50581,"corporation":false,"usgs":true,"family":"Lux","given":"D.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":388734,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Andresen, A.","contributorId":74157,"corporation":false,"usgs":true,"family":"Andresen","given":"A.","email":"","affiliations":[],"preferred":false,"id":388735,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70020820,"text":"70020820 - 1998 - Estimation of density of mongooses with capture-recapture and distance sampling","interactions":[],"lastModifiedDate":"2012-03-12T17:19:51","indexId":"70020820","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2373,"text":"Journal of Mammalogy","onlineIssn":"1545-1542","printIssn":"0022-2372","active":true,"publicationSubtype":{"id":10}},"title":"Estimation of density of mongooses with capture-recapture and distance sampling","docAbstract":"We captured mongooses (Herpestes javanicus) in live traps arranged in trapping webs in Antigua, West Indies, and used capture-recapture and distance sampling to estimate density. Distance estimation and program DISTANCE were used to provide estimates of density from the trapping-web data. Mean density based on trapping webs was 9.5 mongooses/ha (range, 5.9-10.2/ha); estimates had coefficients of variation ranging from 29.82-31.58% (X?? = 30.46%). Mark-recapture models were used to estimate abundance, which was converted to density using estimates of effective trap area. Tests of model assumptions provided by CAPTURE indicated pronounced heterogeneity in capture probabilities and some indication of behavioral response and variation over time. Mean estimated density was 1.80 mongooses/ha (range, 1.37-2.15/ha) with estimated coefficients of variation of 4.68-11.92% (X?? = 7.46%). Estimates of density based on mark-recapture data depended heavily on assumptions about animal home ranges; variances of densities also may be underestimated, leading to unrealistically narrow confidence intervals. Estimates based on trap webs require fewer assumptions, and estimated variances may be a more realistic representation of sampling variation. Because trap webs are established easily and provide adequate data for estimation in a few sample occasions, the method should be efficient and reliable for estimating densities of mongooses.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Mammalogy","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"00222372","usgsCitation":"Corn, J., and Conroy, M., 1998, Estimation of density of mongooses with capture-recapture and distance sampling: Journal of Mammalogy, v. 79, no. 3, p. 1009-1015.","startPage":"1009","endPage":"1015","numberOfPages":"7","costCenters":[],"links":[{"id":230233,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"79","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0b82e4b0c8380cd52758","contributors":{"authors":[{"text":"Corn, J.L.","contributorId":72964,"corporation":false,"usgs":true,"family":"Corn","given":"J.L.","email":"","affiliations":[],"preferred":false,"id":387654,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Conroy, M.J.","contributorId":84690,"corporation":false,"usgs":true,"family":"Conroy","given":"M.J.","email":"","affiliations":[],"preferred":false,"id":387655,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70021119,"text":"70021119 - 1998 - Dynamic stress changes during earthquake rupture","interactions":[],"lastModifiedDate":"2023-10-22T14:53:43.138781","indexId":"70021119","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","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":"Dynamic stress changes during earthquake rupture","docAbstract":"We assess two competing dynamic interpretations that have been proposed for the short slip durations characteristic of kinematic earthquake models derived by inversion of earthquake waveform and geodetic data. The first interpretation would require a fault constitutive relationship in which rapid dynamic restrengthening of the fault surface occurs after passage of the rupture front, a hypothesized mechanical behavior that has been referred to as “self-healing.” The second interpretation would require sufficient spatial heterogeneity of stress drop to permit rapid equilibration of elastic stresses with the residual dynamic friction level, a condition we refer to as “geometrical constraint.” These interpretations imply contrasting predictions for the time dependence of the fault-plane shear stresses. We compare these predictions with dynamic shear stress changes for the 1992 Landers (M 7.3), 1994 Northridge (M 6.7), and 1995 Kobe (M 6.9) earthquakes. Stress changes are computed from kinematic slip models of these earthquakes, using a finite-difference method. For each event, static stress drop is highly variable spatially, with high stress-drop patches embedded in a background of low, and largely negative, stress drop. The time histories of stress change show predominantly monotonic stress change after passage of the rupture front, settling to a residual level, without significant evidence for dynamic restrengthening. The stress change at the rupture front is usually gradual rather than abrupt, probably reflecting the limited resolution inherent in the underlying kinematic inversions. On the basis of this analysis, as well as recent similar results obtained independently for the Kobe and Morgan Hill earthquakes, we conclude that, at the present time, the self-healing hypothesis is unnecessary to explain earthquake kinematics.
Using strong-motion data recorded in the Los Angeles region from the 1992 (Mw 7.3) Landers earthquake, we have tested the accuracy of existing three-dimensional (3D) velocity models on the simulation of long-period (≧2 sec) ground motions in the Los Angeles basin and surrounding San Fernando and San Gabriel Valleys. First, the overall pattern and degree of long-period excitation of the basins were identified in the observations. Within the Los Angeles basin, the recorded amplitudes are about three to four times larger than at sites outside the basins; amplitudes within the San Fernando and San Gabriel Valleys are nearly a factor of 3 greater than surrounding bedrock sites. Then, using a 3D finite-difference numerical modeling approach, we analyzed how variations in 3D earth structure affect simulated waveforms, amplitudes, and the fit to the observed patterns of amplification. Significant differences exist in the 3D velocity models of southern California that we tested (Magistrale et al., 1996; Graves, 1996a; Hauksson and Haase, 1997). Major differences in the models include the velocity of the assumed background models; the depth of the Los Angeles basin; and the depth, location, and geometry of smaller basins. The largest disparities in the response of the models are seen for the San Fernando Valley and the deepest portion of the Los Angeles basin. These arise in large part from variations in the structure of the basins, particularly the effective depth extent, which is mainly due to alternative assumptions about the nature of the basin sediment fill. The general ground-motion characteristics are matched by the 3D model simulations, validating the use of 3D modeling with geologically based velocity-structure models. However, significant shortcomings exist in the overall patterns of amplification and the duration of the long-period response. The successes and limitations of the models for reproducing the recorded ground motions as discussed provide the basis and direction for necessary improvements to earth structure models, whether geologically or tomographically derived. The differences in the response of the earth models tested also translate to variable success in the ability to successfully model the data and add uncertainty to estimates of the basin response given input “scenario” earthquake source models.
The distribution and isotopic composition of helium in sedimentary basins can be used to interpret the ages of very old ground waters. The piston-flow model commonly used in such interpretation, however, does not account for several important factors and as such works well only in very simple flow regimes. In this study of helium transport in a hypothetical sedimentary basin, we develop a numerical model that accounts for the magnitude and distribution of the basal helium flux, hydrodynamic dispersion, and complexities in flow regimes such as subregional flow cells. The modeling shows that these factors exert strong controls on the helium distribution and isotopic composition. The simulations may provide a basis for more accurate interpretations of observed helium concentrations and isotopic ratios in sedimentary basins.
A p finite element scheme and parallel iterative solver are introduced for a modified form of the shallow water equations. The governing equations are the three-dimensional shallow water equations. After a harmonic decomposition in time and rearrangement, the resulting equations are a complex Helmholz problem for surface elevation, and a complex momentum equation for the horizontal velocity. Both equations are nonlinear and the resulting system is solved using the Picard iteration combined with a preconditioned biconjugate gradient (PBCG) method for the linearized subproblems. A subdomain-based parallel preconditioner is developed which uses incomplete LU factorization with thresholding (ILUT) methods within subdomains, overlapping ILUT factorizations for subdomain boundaries and under-relaxed iteration for the resulting block system. The method builds on techniques successfully applied to linear elements by introducing ordering and condensation techniques to handle uniform p refinement. The combined methods show good performance for a range of p (element order), h (element size), and N (number of processors). Performance and scalability results are presented for a field scale problem where up to 512 processors are used.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0309-1708(97)00006-7","usgsCitation":"Barragy, E.J., and Walters, R.A., 1998, Parallel iterative solution for h and p approximations of the shallow water equations: Advances in Water Resources, v. 21, no. 5, p. 327-337, https://doi.org/10.1016/S0309-1708(97)00006-7.","productDescription":"11 p.","startPage":"327","endPage":"337","numberOfPages":"11","costCenters":[],"links":[{"id":229934,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"21","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a74c9e4b0c8380cd77820","contributors":{"authors":[{"text":"Barragy, E. J.","contributorId":27631,"corporation":false,"usgs":true,"family":"Barragy","given":"E.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":388632,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Walters, R. A.","contributorId":34174,"corporation":false,"usgs":true,"family":"Walters","given":"R.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":388633,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70021088,"text":"70021088 - 1998 - Use of fault striations and dislocation models to infer tectonic shear stress during the 1995 Hyogo-Ken Nanbu (Kobe) earthquake","interactions":[],"lastModifiedDate":"2023-10-25T00:03:20.939178","indexId":"70021088","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","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":"Use of fault striations and dislocation models to infer tectonic shear stress during the 1995 Hyogo-Ken Nanbu (Kobe) earthquake","docAbstract":"Dislocation models of the 1995 Hyogo-ken Nanbu (Kobe) earthquake derived by Yoshida et al. (1996) show substantial changes in direction of slip with time at specific points on the Nojima and Rokko fault systems, as do striations we observed on exposures of the Nojima fault surface on Awaji Island. Spudich (1992) showed that the initial stress, that is, the shear traction on the fault before the earthquake origin time, can be derived at points on the fault where the slip rake rotates with time if slip velocity and stress change are known at these points. From Yoshida's slip model, we calculated dynamic stress changes on the ruptured fault surfaces. To estimate errors, we compared the slip velocities and dynamic stress changes of several published models of the earthquake. The differences between these models had an exponential distribution, not gaussian. We developed a Bayesian method to estimate the probability density function (PDF) of initial stress from the striations and from Yoshida's slip model. Striations near Toshima and Hirabayashi give initial stresses of about 13 and 7 MPa, respectively. We obtained initial stresses of about 7 to 17 MPa at depths of 2 to 10 km on a subset of points on the Nojima and Rokko fault systems. Our initial stresses and coseismic stress changes agree well with postearthquake stresses measured by hydrofracturing in deep boreholes near Hirabayashi and Ogura on Awaji Island. Our results indicate that the Nojima fault slipped at very low shear stress, and fractional stress drop was complete near the surface and about 32% below depths of 2 km. Our results at depth depend on the accuracy of the rake rotations in Yoshida's model, which are probably correct on the Nojima fault but debatable on the Rokko fault. Our results imply that curved or cross-cutting fault striations can be formed in a single earthquake, contradicting a common assumption of structural geology.","language":"English","publisher":"Seismological Society of America","doi":"10.1785/BSSA0880020413","issn":"00371106","usgsCitation":"Spudich, P., Guatteri, M., Otsuki, K., and Minagawa, J., 1998, Use of fault striations and dislocation models to infer tectonic shear stress during the 1995 Hyogo-Ken Nanbu (Kobe) earthquake: Bulletin of the Seismological Society of America, v. 88, no. 2, p. 413-427, https://doi.org/10.1785/BSSA0880020413.","productDescription":"13 p.","startPage":"413","endPage":"427","numberOfPages":"15","costCenters":[],"links":[{"id":229851,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Japan","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n 134.38242996352392,\n 34.880736815877626\n ],\n [\n 134.38242996352392,\n 34.45605646653874\n ],\n [\n 135.64585769789886,\n 34.45605646653874\n ],\n [\n 135.64585769789886,\n 34.880736815877626\n ],\n [\n 134.38242996352392,\n 34.880736815877626\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"88","issue":"2","noUsgsAuthors":false,"publicationDate":"1998-04-01","publicationStatus":"PW","scienceBaseUri":"505bbefce4b08c986b3298d4","contributors":{"authors":[{"text":"Spudich, P.","contributorId":85700,"corporation":false,"usgs":true,"family":"Spudich","given":"P.","affiliations":[],"preferred":false,"id":388609,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Guatteri, Mariagiovanna","contributorId":29979,"corporation":false,"usgs":true,"family":"Guatteri","given":"Mariagiovanna","email":"","affiliations":[],"preferred":false,"id":388606,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Otsuki, K.","contributorId":41616,"corporation":false,"usgs":true,"family":"Otsuki","given":"K.","email":"","affiliations":[],"preferred":false,"id":388608,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Minagawa, J.","contributorId":31141,"corporation":false,"usgs":true,"family":"Minagawa","given":"J.","email":"","affiliations":[],"preferred":false,"id":388607,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70021085,"text":"70021085 - 1998 - Mass collecting and the diet breadth model: A Great Basin example","interactions":[],"lastModifiedDate":"2024-04-15T16:50:09.085928","indexId":"70021085","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2182,"text":"Journal of Archaeological Science","active":true,"publicationSubtype":{"id":10}},"title":"Mass collecting and the diet breadth model: A Great Basin example","docAbstract":"The energetic return rates of many small animal and plant resources are often density dependent. When these resources are collected in mass, change in abundance can dramatically affect diet rank, and challenges the assumption that return rates are generally correlated with body size. When mass collecting is employed, as a result of either natural events (e.g. windrows) or technological developments (e.g. nets), population density may largely determine the overall return rate for a resource. Since a single food or resource type can be many prey types, an increase in the abundance of a food resource can change its diet rank. We examined this relationship at Lakeside Cave in northwestern Utah, and discovered that when the abundance of grasshoppers is high, and mass collecting is productive, the hunting of bighorn sheep and other large animal resources may have been abandoned, contradicting commonly held assumptions about prey size. In archaeological situations it may be necessary to determine what foraging technique was used before assuming that the presence of small animals and fish in the diet is a result of reduced foraging efficiency.
","language":"English","publisher":"Elsevier","doi":"10.1006/jasc.1997.0245","issn":"03054403","usgsCitation":"Madsen, D., and Schmitt, D., 1998, Mass collecting and the diet breadth model: A Great Basin example: Journal of Archaeological Science, v. 25, no. 5, p. 445-455, https://doi.org/10.1006/jasc.1997.0245.","productDescription":"11 p.","startPage":"445","endPage":"455","numberOfPages":"11","costCenters":[],"links":[{"id":229810,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a524be4b0c8380cd6c2e5","contributors":{"authors":[{"text":"Madsen, D.B.","contributorId":65615,"corporation":false,"usgs":true,"family":"Madsen","given":"D.B.","email":"","affiliations":[],"preferred":false,"id":388599,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Schmitt, D.N.","contributorId":103433,"corporation":false,"usgs":true,"family":"Schmitt","given":"D.N.","email":"","affiliations":[],"preferred":false,"id":388600,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70021082,"text":"70021082 - 1998 - A decision support model to assess vulnerability to salt water intrusion in the great bend prairie aquifer of Kansas","interactions":[],"lastModifiedDate":"2024-03-07T11:54:38.695071","indexId":"70021082","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3825,"text":"Groundwater","active":true,"publicationSubtype":{"id":10}},"title":"A decision support model to assess vulnerability to salt water intrusion in the great bend prairie aquifer of Kansas","docAbstract":"A relatively simple ground water decision support system (DSS) was developed to assist in identifying salt-water vulnerable areas and in developing management policies to prevent salt-water intrusion in central Kansas. The DSS is based on a combination of numerical modeling sensitivity analyses, multiple regression analyses, and classification procedures derived from our knowledge of the area. Six ground water salinity models are proposed to evaluate irrigation well permit applications. The choice of model depends on the availability of site-specific data. The DSS takes advantage of GIS database management procedures, and is applied to an actual salt-water intrusion problem site in south-central Kansas. This approach can help local ground water management districts make better decisions on protecting ground water use in salt water vulnerable areas.
In this, the first of two papers concerned with the use of numerical simulation to examine flow and transport parameters in heterogeneous porous media via Monte Carlo methods, various aspects of the modelling effort are examined. In particular, the need to save on core memory causes one to use only specific realizations that have certain initial characteristics; in effect, these transport simulations are conditioned by these characteristics. Also, the need to independently estimate length scales for the generated fields is discussed. The statistical uniformity of the flow field is investigated by plotting the variance of the seepage velocity for vector components in the x, y, and z directions. Finally, specific features of the velocity field itself are illuminated in this first paper. In particular, these data give one the opportunity to investigate the effective hydraulic conductivity in a flow field which is approximately statistically uniform; comparisons are made with first- and second-order perturbation analyses. The mean cloud velocity is examined to ascertain whether it is identical to the mean seepage velocity of the model. Finally, the variance in the cloud centroid velocity is examined for the effect of source size and differing strengths of local transverse dispersion.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/97WR02712","usgsCitation":"Naff, R., Haley, D., and Sudicky, E., 1998, High-resolution Monte Carlo simulation of flow and conservative transport in heterogeneous porous media: 1. Methodology and flow results: Water Resources Research, v. 34, no. 4, p. 663-677, https://doi.org/10.1029/97WR02712.","productDescription":"15 p.","startPage":"663","endPage":"677","costCenters":[],"links":[{"id":229694,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"34","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3110e4b0c8380cd5dbd1","contributors":{"authors":[{"text":"Naff, R.L.","contributorId":86349,"corporation":false,"usgs":true,"family":"Naff","given":"R.L.","affiliations":[],"preferred":false,"id":388583,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Haley, D.F.","contributorId":68480,"corporation":false,"usgs":true,"family":"Haley","given":"D.F.","email":"","affiliations":[],"preferred":false,"id":388582,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Sudicky, E.A.","contributorId":67237,"corporation":false,"usgs":true,"family":"Sudicky","given":"E.A.","email":"","affiliations":[],"preferred":false,"id":388581,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021068,"text":"70021068 - 1998 - An expandable radiocollar for elk calves","interactions":[],"lastModifiedDate":"2012-03-12T17:19:48","indexId":"70021068","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3779,"text":"Wildlife Society Bulletin","onlineIssn":"1938-5463","printIssn":"0091-7648","active":true,"publicationSubtype":{"id":10}},"title":"An expandable radiocollar for elk calves","docAbstract":"Expandable radiocollars, designed to monitor juvenile survival and movements, were placed on 132 neonatal elk (Cervus elaphus) in Yellowstone National Park during 1987-1990. A modified design of the same collar was placed on 164 neonates of the Jackson elk herd in northwest Wyoming during 1990-1992. One of the Yellowstone calves and 19 of the Jackson calves cast their collars before 15 July of their birth year. General deterioration of collar materials resulted in loss of the Yellowstone collars 12-18 months post-deployment. Separation of breakaway tabs resulted in loss of 13 collars from Jackson elk 504 ?? 60 days post-deployment, but the remaining collars remained on elk for ???4 years. These light-weight and adaptable collar designs achieved study objectives. We provide design recommendations for future monitoring of juvenile elk.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Wildlife Society Bulletin","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"00917648","usgsCitation":"Smith, B., Burger, W., and Singer, F.J., 1998, An expandable radiocollar for elk calves: Wildlife Society Bulletin, v. 26, no. 1, p. 113-117.","startPage":"113","endPage":"117","numberOfPages":"5","costCenters":[],"links":[{"id":230134,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"26","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ea61e4b0c8380cd48812","contributors":{"authors":[{"text":"Smith, B.L.","contributorId":39740,"corporation":false,"usgs":true,"family":"Smith","given":"B.L.","email":"","affiliations":[],"preferred":false,"id":388548,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Burger, W.P.","contributorId":33082,"corporation":false,"usgs":true,"family":"Burger","given":"W.P.","email":"","affiliations":[],"preferred":false,"id":388547,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Singer, F. J.","contributorId":97848,"corporation":false,"usgs":true,"family":"Singer","given":"F.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":388549,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021064,"text":"70021064 - 1998 - Physiological tolerances of juvenile robust redhorse, Moxostoma robustum: Conservation implications for an imperiled species","interactions":[],"lastModifiedDate":"2012-03-12T17:19:48","indexId":"70021064","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1528,"text":"Environmental Biology of Fishes","active":true,"publicationSubtype":{"id":10}},"title":"Physiological tolerances of juvenile robust redhorse, Moxostoma robustum: Conservation implications for an imperiled species","docAbstract":"The robust redhorse, Moxostoma robustum (Teleostei: Catostomidae), is an imperiled sucker native to large rivers of the Atlantic slope of the southeastern United States. Juvenile M. robustum were tested for tolerances to temperature, salinity, pH, and hypoxia in order to evaluate basic early life-history requirements. Static (acute) tests resulted in estimates of mean lower temperature tolerances (5.3-19.4 ??C) that varied with prior thermal acclimation and indicated no apparent difference in tolerance among fish 30, 60, and 90 days old. Fish acclimated to 20 ??C and 30 ??C had significantly different mean critical thermal maxima (34.9 ??C and 37.2 ??C, respectively) and exhibited pronounced increased opercular ventilation rates with elevated temperatures. Fish exposed to acute and chronic increases in salinity showed unusual patterns of mortality above the isosmotic point (9 ppt) that reflected possible differences in body mass and prior acclimation conditions (i.e., water ionic composition); small fish and those held in soft water were the least tolerant of increased salinity. Abrupt exposure to extreme pH values resulted in greater than 50% mortality at pH values below 4.3 and above 9.5 within a 96-hour period. Fish exposed to progressive hypoxia utilized aquatic surface respiration at a mean oxygen concentration of 0.72-0.80 mg O2 l-1 (20 ??C and 30 ??C acclimated fish, respectively), and lost equilibrium at 0.54-.57 mg O2 l-1. Juvenile M. robustum are moderately tolerant of a wide range of ambient physicochemical parameters, but further research is needed to determine how both abiotic and biotic factors have contributed to population decline and extirpation of this species.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Biology of Fishes","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1023/A:1007486632102","issn":"03781909","usgsCitation":"Walsh, S., Haney, D.C., Timmerman, C.M., and Dorazio, R., 1998, Physiological tolerances of juvenile robust redhorse, Moxostoma robustum: Conservation implications for an imperiled species: Environmental Biology of Fishes, v. 51, no. 4, p. 429-444, https://doi.org/10.1023/A:1007486632102.","startPage":"429","endPage":"444","numberOfPages":"16","costCenters":[],"links":[{"id":206519,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1007486632102"},{"id":230089,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"51","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7b29e4b0c8380cd792b3","contributors":{"authors":[{"text":"Walsh, S. J. 0000-0002-1009-8537","orcid":"https://orcid.org/0000-0002-1009-8537","contributorId":62171,"corporation":false,"usgs":true,"family":"Walsh","given":"S. J.","affiliations":[],"preferred":false,"id":388514,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Haney, D. C.","contributorId":97854,"corporation":false,"usgs":true,"family":"Haney","given":"D.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":388515,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Timmerman, C. M.","contributorId":98898,"corporation":false,"usgs":true,"family":"Timmerman","given":"C.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":388516,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Dorazio, R.M. 0000-0003-2663-0468","orcid":"https://orcid.org/0000-0003-2663-0468","contributorId":23475,"corporation":false,"usgs":true,"family":"Dorazio","given":"R.M.","affiliations":[],"preferred":false,"id":388513,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70021063,"text":"70021063 - 1998 - Black Mats, Spring-Fed Streams, and Late-Glacial-Age Recharge in the Southern Great Basin","interactions":[],"lastModifiedDate":"2013-01-25T13:22:17","indexId":"70021063","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3218,"text":"Quaternary Research","active":true,"publicationSubtype":{"id":10}},"title":"Black Mats, Spring-Fed Streams, and Late-Glacial-Age Recharge in the Southern Great Basin","docAbstract":"Black mats are prominent features of the late Pleistocene and Holocene stratigraphic record in the southern Great Basin. Faunal, geochemical, and sedimentological evidence shows that the black mats formed in several microenvironments related to spring discharge, ranging from wet meadows to shallow ponds. Small land snails such as Gastrocopta tappaniana and Vertigo berryi are the most common mollusk taxa present. Semiaquatic and aquatic taxa are less abundant and include Catinellids, Fossaria parva, Gyraulus parvus, and others living today in and around perennial seeps and ponds. The ostracodes Cypridopsis okeechobi and Scottia tumida, typical of seeps and low-discharge springs today, as well as other taxa typical of springs and wetlands, are common in the black mats. Several new species that lived in the saturated subsurface also are present, but lacustrine ostracodes are absent. The ??13C values of organic matter in the black mats range from -12 to -26???, reflecting contributions of tissue from both C3 (sedges, most shrubs and trees) and C4 (saltbush, saltgrass) plants. Carbon-14 dates on the humate fraction of 55 black mats fall between 11,800 to 6300 and 2300 14C yr B.P. to modern. The total absence of mats in our sample between 6300 and 2300 14C yr B.P. likely reflects increased aridity associated with the mid-Holocene Altithermal. The oldest black mats date to 11,800-11,600 14C yr B.P., and the peak in the 14C black mat distribution falls at ???10,000 14C yr B.P. As the formation of black mats is spring related, their abundance reflects refilling of valley aquifers starting no later than 11,800 and peaking after 11,000 14C yrB.P. Reactivation of spring-fed channels shortly before 11,200 14C yr B.P. is also apparent in the stratigraphic records from the Las Vegas and Pahrump Valleys. This age distribution suggests that black mats and related spring-fed channels in part may have formed in response to Younger Dryas (YD)-age recharge in the region. However, the inception of black mat formation precedes that of the YD by at least 400 14C yr, and hydrological change is gradual, not rapid. ?? 1998 University of Washington.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Quaternary Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","publisherLocation":"Amsterdam, Netherlands","doi":"10.1006/qres.1997.1959","issn":"00335894","usgsCitation":"Quade, J., Forester, R.M., Pratt, W., and Carter, C., 1998, Black Mats, Spring-Fed Streams, and Late-Glacial-Age Recharge in the Southern Great Basin: Quaternary Research, v. 49, no. 2, p. 129-148, https://doi.org/10.1006/qres.1997.1959.","startPage":"129","endPage":"148","numberOfPages":"20","costCenters":[],"links":[{"id":230050,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":266457,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1006/qres.1997.1959"}],"volume":"49","issue":"2","noUsgsAuthors":false,"publicationDate":"2017-01-20","publicationStatus":"PW","scienceBaseUri":"5059f1d5e4b0c8380cd4ae54","contributors":{"authors":[{"text":"Quade, Jay","contributorId":22108,"corporation":false,"usgs":false,"family":"Quade","given":"Jay","affiliations":[{"id":7042,"text":"University of Arizona","active":true,"usgs":false}],"preferred":false,"id":388509,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Forester, R. M.","contributorId":76332,"corporation":false,"usgs":true,"family":"Forester","given":"R.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":388511,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Pratt, W.L.","contributorId":59972,"corporation":false,"usgs":true,"family":"Pratt","given":"W.L.","email":"","affiliations":[],"preferred":false,"id":388510,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Carter, C.","contributorId":96293,"corporation":false,"usgs":true,"family":"Carter","given":"C.","email":"","affiliations":[],"preferred":false,"id":388512,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70021059,"text":"70021059 - 1998 - Flow modeling and permeability estimation using borehole flow logs in heterogeneous fractured formations","interactions":[],"lastModifiedDate":"2018-03-16T09:56:24","indexId":"70021059","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","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":"Flow modeling and permeability estimation using borehole flow logs in heterogeneous fractured formations","docAbstract":"A numerical model of flow in the vicinity of a borehole is used to analyze flowmeter data obtained with high-resolution flowmeters. The model is designed to (1) precisely compute flow in a borehole, (2) approximate the effects of flow in surrounding aquifers on the measured borehole flow, (3) allow for an arbitrary number (N) of entry/exit points connected to M < N far-field aquifers, and (4) be consistent with the practical limitations of flowmeter measurements such as limits of resolution, typical measurement error, and finite measurement periods. The model is used in three modes: (1) a quasi-steady pumping mode where there is no ambient flow, (2) a steady flow mode where ambient differences in far-field water levels drive flow between fracture zones in the borehole, and (3) a cross-borehole test mode where pumping in an adjacent borehole drives flow in the observation borehole. The model gives estimates of transmissivity for any number of fractures in steady or quasi-steady flow experiments that agree with straddle-packer test data. Field examples show how these cross-borehole-type curves can be used to estimate the storage coefficient of fractures and bedding planes and to determine whether fractures intersecting a borehole at different locations are hydraulically connected in the surrounding rock mass.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/98WR00268","usgsCitation":"Paillet, F.L., 1998, Flow modeling and permeability estimation using borehole flow logs in heterogeneous fractured formations: Water Resources Research, v. 34, no. 5, p. 997-1010, https://doi.org/10.1029/98WR00268.","productDescription":"14 p.","startPage":"997","endPage":"1010","costCenters":[],"links":[{"id":230009,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"34","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a1247e4b0c8380cd5423e","contributors":{"authors":[{"text":"Paillet, Frederick L.","contributorId":63820,"corporation":false,"usgs":true,"family":"Paillet","given":"Frederick","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":388478,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70021055,"text":"70021055 - 1998 - Consequences of cannibalism and competition for food in a smallmouth bass population: An individual-based modeling study","interactions":[],"lastModifiedDate":"2016-01-05T14:56:13","indexId":"70021055","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","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":"Consequences of cannibalism and competition for food in a smallmouth bass population: An individual-based modeling study","docAbstract":"We used an individual-based modeling approach to study the consequences of cannibalism and competition for food in a freshwater fish population. We simulated the daily foraging, growth, and survival of the age-0 fish and older juvenile individuals of a sample population to reconstruct patterns of density dependence in the age-0 fish during the growth season. Cannibalism occurs as a part of the foraging process. For age-0 fish, older juvenile fish are both potential cannibals and competitors of food. We found that competition and cannibalism produced intraclass and interclass density dependence. Our modeling results suggested the following. (1) With low density of juvenile fish and weak interclass interactions, the age-0 fish recruitment shows a Beverton-Holt type of density dependence. (2) With high density of juvenile fish and strong interclass interactions, the age-0 fish recruitment shows a Ricker type of density dependence, and overcompensation occurs. (3) Interclass competition of food is responsible for much of the overcompensation. (4) Cannibalism intensifies the changes in the recruitment that are brought about by competition. Cannibalism can (a) generally reduce the recruitment, (b) particularly reduce the maximum level of recruitment, (c) cause overcompensation to occur at lower densities, and (d) produce a stronger overcompensation. (5) Growth is also a function of density. Cannibalism generally improves average growth of cannibals. (6) Variation in the lengths of age-0 fish increases with density and with a decreased average growth. These results imply that cannibalism and competition for food could strongly affect recruitment dynamics. Our model also showed that the rate of cannibalism either could be fairly even through the whole season or could vary dramatically. The individual-based modeling approach can help ecologists understand the mechanistic connection between daily behavioral and physiological processes operating at the level of individual organisms and seasonal patterns of population structure and dynamics. ?? Copyright by the American Fisheries Society 1998.
","language":"English","publisher":"Taylor & Francis","doi":"10.1577/1548-8659(1998)127<0174:COCACF>2.0.CO;2","usgsCitation":"Dong, Q., and DeAngelis, D., 1998, Consequences of cannibalism and competition for food in a smallmouth bass population: An individual-based modeling study: Transactions of the American Fisheries Society, v. 127, no. 2, p. 174-189, https://doi.org/10.1577/1548-8659(1998)127<0174:COCACF>2.0.CO;2.","productDescription":"16 p.","startPage":"174","endPage":"189","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":487385,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1577/1548-8659(1998)127<0174:cocacf>2.0.co;2","text":"Publisher Index Page"},{"id":229932,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"127","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f9d4e4b0c8380cd4d7da","contributors":{"authors":[{"text":"Dong, Q.","contributorId":39152,"corporation":false,"usgs":true,"family":"Dong","given":"Q.","email":"","affiliations":[],"preferred":false,"id":388470,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"DeAngelis, D.L. 0000-0002-1570-4057","orcid":"https://orcid.org/0000-0002-1570-4057","contributorId":32470,"corporation":false,"usgs":true,"family":"DeAngelis","given":"D.L.","affiliations":[],"preferred":false,"id":388469,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70020819,"text":"70020819 - 1998 - Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams","interactions":[],"lastModifiedDate":"2018-03-16T10:01:07","indexId":"70020819","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","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":"Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams","title":"Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams","docAbstract":"Groundwater and stream water data collected at three headwater catchments in the Neversink River watershed indicate that base flow is sustained by groundwater from two sources: a shallow flow system within the till and soil and a deep flow system within bedrock fractures and bedding planes that discharges as perennial springs. Data from eight wells finished near the till/bedrock interface indicate that saturated conditions are not maintained in the shallow flow system during most summers. In contrast, the discharge of a perennial spring remained constant during two summer rainstorms, providing evidence that the deep flow system is disconnected from the shallow flow system in summer. Discharge from perennial springs was the principal source of streamflow in a headwater reach during low flow. Mean NO3− concentrations were 20–25 μmol L−1 in five perennial springs during the summer but only 5–10 μmol L−1 in shallow groundwater. Thus the deep flow system does not reflect typical NO3− concentrations in the soil during summer. A hydrologic budget at a headwater drainage reveals that March and late fall are the principal groundwater recharge periods. Residence time modeling based on analyses of 18O and 35S indicates that groundwater in the deep flow system is 6–22 months old. These data indicate that summer base flow largely originates from previous dormant seasons when available soil NO3− is greater. In these Catskill watersheds, high base flow concentrations of NO3− during summer do not provide sufficient evidence that the atmospheric N deposition rate exceeds the demand of terrestrial vegetation.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/98WR01282","usgsCitation":"Burns, D.A., Murdoch, P.S., Lawrence, G.B., and Michel, R.L., 1998, Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams: Water Resources Research, v. 34, no. 8, p. 1987-1996, https://doi.org/10.1029/98WR01282.","productDescription":"10 p.","startPage":"1987","endPage":"1996","costCenters":[],"links":[{"id":487361,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/98wr01282","text":"Publisher Index Page"},{"id":230195,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","volume":"34","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a05e6e4b0c8380cd50ff8","contributors":{"authors":[{"text":"Burns, Douglas A. 0000-0001-6516-2869 daburns@usgs.gov","orcid":"https://orcid.org/0000-0001-6516-2869","contributorId":1237,"corporation":false,"usgs":true,"family":"Burns","given":"Douglas","email":"daburns@usgs.gov","middleInitial":"A.","affiliations":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"preferred":true,"id":387650,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Murdoch, Peter S. 0000-0001-9243-505X pmurdoch@usgs.gov","orcid":"https://orcid.org/0000-0001-9243-505X","contributorId":2453,"corporation":false,"usgs":true,"family":"Murdoch","given":"Peter","email":"pmurdoch@usgs.gov","middleInitial":"S.","affiliations":[{"id":5067,"text":"Northeast Regional Director's Office","active":true,"usgs":true}],"preferred":true,"id":387651,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lawrence, Gregory B. 0000-0002-8035-2350 glawrenc@usgs.gov","orcid":"https://orcid.org/0000-0002-8035-2350","contributorId":867,"corporation":false,"usgs":true,"family":"Lawrence","given":"Gregory","email":"glawrenc@usgs.gov","middleInitial":"B.","affiliations":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"preferred":true,"id":387652,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Michel, Robert L. rlmichel@usgs.gov","contributorId":823,"corporation":false,"usgs":true,"family":"Michel","given":"Robert","email":"rlmichel@usgs.gov","middleInitial":"L.","affiliations":[{"id":148,"text":"Branch of Regional Research-Western Region","active":false,"usgs":true}],"preferred":true,"id":387653,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70020818,"text":"70020818 - 1998 - Oxygen and hydrogen isotope systematics of Lake Baikal, Siberia: Implications for paleoclimate studies","interactions":[],"lastModifiedDate":"2012-03-12T17:19:51","indexId":"70020818","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2620,"text":"Limnology and Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"Oxygen and hydrogen isotope systematics of Lake Baikal, Siberia: Implications for paleoclimate studies","docAbstract":"We interpret oxygen and hydrogen isotope data for water samples from Lake Baikal, Siberia, its tributaries and other local rivers, and local precipitation in terms of the known water budget for the modem lake in order to gain insight into past limnological and climatic processes that influenced the lake. Lake Baikal is remarkably uniform in its isotopic composition (??18O = -15.8 ?? 0.2???; ??D = -123 ?? 2???) and lies slightly to the right of the global meteoric water line, which suggests significant evaporation. Water is supplied to the lake by over 300 rivers and streams. The oxygen isotope values (??18O) of the rivers in the Baikal catchment range from -13.4 to -21.2???. The hydrogen isotope values (??D) for the same area range from -103 to -156???. Both these ranges generally conform to the global meteoric water line. The weighted average isotopic composition of input to the lake (rivers plus precipitation) is -15.2??? for ??18O and -116??? for ??D, values higher than those of the modem lake. Therefore, the isotopic composition of the modem lake cannot be related to the modem input through simple evaporation. Instead, modeling of the isotopic mass balance of the lake suggests that inputs (precipitation and influx from rivers) and outputs (evaporation and outflow) are not at a steady-state equilibrium under current climate conditions. We found previous input to the lake had lower ??18O and ??D values than modem input, which reflects cooler climates in the past compared with modern conditions. Under constant climate conditions, steady-state conditions are not expected to be reached by the lake for at least 700 yr because of its large size and the long residence time of water in the lake.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Limnology and Oceanography","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"00243590","usgsCitation":"Seal, R., and Shanks, W.C., 1998, Oxygen and hydrogen isotope systematics of Lake Baikal, Siberia: Implications for paleoclimate studies: Limnology and Oceanography, v. 43, no. 6, p. 1251-1261.","startPage":"1251","endPage":"1261","numberOfPages":"11","costCenters":[],"links":[{"id":230194,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"43","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7281e4b0c8380cd76b33","contributors":{"authors":[{"text":"Seal, R.R. II","contributorId":102097,"corporation":false,"usgs":true,"family":"Seal","given":"R.R.","suffix":"II","email":"","affiliations":[],"preferred":false,"id":387649,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Shanks, Wayne C. III","contributorId":100527,"corporation":false,"usgs":true,"family":"Shanks","given":"Wayne","suffix":"III","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":387648,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70020817,"text":"70020817 - 1998 - An empirical model of the tidal currents in the Gulf of the Farallones","interactions":[],"lastModifiedDate":"2012-03-12T17:19:51","indexId":"70020817","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1371,"text":"Deep-Sea Research Part II: Topical Studies in Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"An empirical model of the tidal currents in the Gulf of the Farallones","docAbstract":"Candela et al. (1990, 1992) showed that tides in an open ocean region can be resolved using velocity data from a ship-mounted ADCP. We use their method to build a spatially varying model of the tidal currents in the Gulf of the Farallones, an area of complicated bathymetry where the tidal velocities in some parts of the region are weak compared to the mean currents. We describe the tidal fields for the M2, S2, K1, and O1 constituents and show that this method is sensitive to the model parameters and the quantity of input data. In areas with complex bathymetry and tidal structures, a large amount of spatial data is needed to resolve the tides. A method of estimating the associated errors inherent in the model is described.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Deep-Sea Research Part II: Topical Studies in Oceanography","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0967-0645(98)80004-0","issn":"09670645","usgsCitation":"Steger, J., Collins, C.A., Schwing, F., Noble, M., Garfield, N., and Steiner, M., 1998, An empirical model of the tidal currents in the Gulf of the Farallones: Deep-Sea Research Part II: Topical Studies in Oceanography, v. 45, no. 8-9, p. 1471-1505, https://doi.org/10.1016/S0967-0645(98)80004-0.","startPage":"1471","endPage":"1505","numberOfPages":"35","costCenters":[],"links":[{"id":230193,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206555,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0967-0645(98)80004-0"}],"volume":"45","issue":"8-9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ea38e4b0c8380cd486fc","contributors":{"authors":[{"text":"Steger, J.M.","contributorId":10189,"corporation":false,"usgs":true,"family":"Steger","given":"J.M.","email":"","affiliations":[],"preferred":false,"id":387642,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Collins, C. A.","contributorId":43731,"corporation":false,"usgs":true,"family":"Collins","given":"C.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":387646,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Schwing, F.B.","contributorId":24516,"corporation":false,"usgs":true,"family":"Schwing","given":"F.B.","email":"","affiliations":[],"preferred":false,"id":387644,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Noble, M.","contributorId":15340,"corporation":false,"usgs":true,"family":"Noble","given":"M.","email":"","affiliations":[],"preferred":false,"id":387643,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Garfield, N.","contributorId":62364,"corporation":false,"usgs":true,"family":"Garfield","given":"N.","email":"","affiliations":[],"preferred":false,"id":387647,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Steiner, M.T.","contributorId":26102,"corporation":false,"usgs":true,"family":"Steiner","given":"M.T.","email":"","affiliations":[],"preferred":false,"id":387645,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ]}