Only five moderate and large earthquakes (Mw ≥5.7) in India—three in the Indian shield region and two in the Himalayan arc region—have given rise to multiple strong ground-motion recordings. Near-source data are available for only two of these events. The Bhuj earthquake (Mw 7.6), which occurred in the shield region, gave rise to useful recordings at distances exceeding 550 km. Because of the scarcity of the data, we use the stochastic method to estimate ground motions. We assume that (1) S waves dominate at R < 100 km and Lg waves at R ≥ 100 km, (2) Q = 508f0.48 is valid for the Indian shield as well as the Himalayan arc region, (3) the effective duration is given by fc-1 + 0.05R, where fc is the corner frequency, and R is the hypocentral distance in kilometer, and (4) the acceleration spectra are sharply cut off beyond 35 Hz. We use two finite-source stochastic models. One is an approximate model that reduces to the ω2-source model at distances greater that about twice the source dimension. This model has the advantage that the ground motion is controlled by the familiar stress parameter, Δσ. In the other finite-source model, which is more reliable for near-source ground-motion estimation, the high-frequency radiation is controlled by the strength factor, sfact, a quantity that is physically related to the maximum slip rate on the fault. We estimate Δσ needed to fit the observed Amax and Vmax data of each earthquake (which are mostly in the far field). The corresponding sfact is obtained by requiring that the predicted curves from the two models match each other in the far field up to a distance of about 500 km. The results show: (1) The Δσ that explains Amax data for shield events may be a function of depth, increasing from ∼50 bars at 10 km to ∼400 bars at 36 km. The corresponding sfact values range from 1.0-2.0. The Δσ values for the two Himalayan arc events are 75 and 150 bars (sfact = 1.0 and 1.4). (2) The Δσ required to explain Vmax data is, roughly, half the corresponding value for Amax, while the same sfact explains both sets of data. (3) The available far-field Amax and Vmax data for the Bhuj mainshock are well explained by Δσ = 200 and 100 bars, respectively, or, equivalently, by sfact = 1.4. The predicted Amax and Vmax in the epicentral region of this earthquake are 0.80 to 0.95 g and 40 to 55 cm/sec, respectively.
In Africa the variability of rainfall in space and time is high, and the general availability of historical gauge data is low. This makes many food security and hydrologic preparedness activities difficult. In order to help overcome this limitation, we have created the Collaborative Historical African Rainfall Model (CHARM). CHARM combines three sources of information: climatologically aided interpolated (CAI) rainfall grids (monthly/0.5° ), National Centers for Environmental Prediction reanalysis precipitation fields (daily/1.875° ) and orographic enhancement estimates (daily/0.1° ). The first set of weights scales the daily reanalysis precipitation fields to match the gridded CAI monthly rainfall time series. This produces data with a daily/0.5° resolution. A diagnostic model of orographic precipitation, VDELB—based on the dot-product of the surface wind V and terrain gradient (DEL) and atmospheric buoyancy B—is then used to estimate the precipitation enhancement produced by complex terrain. Although the data are produced on 0.1° grids to facilitate integration with satellite-based rainfall estimates, the ‘true’ resolution of the data will be less than this value, and varies with station density, topography, and precipitation dynamics. The CHARM is best suited, therefore, to applications that integrate rainfall or rainfall-driven model results over large regions.
\nThe CHARM time series is compared with three independent datasets: dekadal satellite-based rainfall estimates across the continent, dekadal interpolated gauge data in Mali, and daily interpolated gauge data in western Kenya. These comparisons suggest reasonable accuracies (standard errors of about half a standard deviation) when data are aggregated to regional scales, even at daily time steps. Thus constrained, numerical weather prediction precipitation fields do a reasonable job of representing large-scale diurnal variations.
\nMixing models provide a useful null hypothesis against which to evaluate processes controlling stream water chemical data. Because conservative mixing of end‐members with constant concentration is a linear process, a number of simple mathematical and multivariate statistical methods can be applied to this problem. Although mixing models have been most typically used in the context of mixing soil and groundwater end‐members, an extension of the mathematics of mixing models is presented that assesses the “fit” of a multivariate data set to a lower dimensional mixing subspace without the need for explicitly identified end‐members. Diagnostic tools are developed to determine the approximate rank of the data set and to assess lack of fit of the data. This permits identification of processes that violate the assumptions of the mixing model and can suggest the dominant processes controlling stream water chemical variation. These same diagnostic tools can be used to assess the fit of the chemistry of one site into the mixing subspace of a different site, thereby permitting an assessment of the consistency of controlling end‐members across sites. This technique is applied to a number of sites at the Panola Mountain Research Watershed located near Atlanta, Georgia.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2002WR001528","usgsCitation":"Hooper, R.P., 2003, Diagnostic tools for mixing models of stream water chemistry: Water Resources Research, v. 39, no. 3, p. 2-1-2-13, https://doi.org/10.1029/2002WR001528.","productDescription":"Article 1055; 13 p.","startPage":"2-1","endPage":"2-13","costCenters":[],"links":[{"id":235052,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"39","issue":"3","noUsgsAuthors":false,"publicationDate":"2003-03-14","publicationStatus":"PW","scienceBaseUri":"505a00a3e4b0c8380cd4f82a","contributors":{"authors":[{"text":"Hooper, Richard P.","contributorId":19144,"corporation":false,"usgs":true,"family":"Hooper","given":"Richard","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":407090,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70025801,"text":"70025801 - 2003 - Bayesian Estimations of Peak Ground Acceleration and 5% Damped Spectral Acceleration from Modified Mercalli Intensity Data","interactions":[],"lastModifiedDate":"2012-03-12T17:20:32","indexId":"70025801","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1436,"text":"Earthquake Spectra","active":true,"publicationSubtype":{"id":10}},"title":"Bayesian Estimations of Peak Ground Acceleration and 5% Damped Spectral Acceleration from Modified Mercalli Intensity Data","docAbstract":"We describe a new probabilistic method that uses observations of modified Mercalli intensity (MMI) from past earthquakes to make quantitative estimates of ground shaking parameters (i.e., peak ground acceleration, peak ground velocity, 5% damped spectral acceleration values, etc.). The method uses a Bayesian approach to make quantitative estimates of the probabilities of different levels of ground motions from intensity data given an earthquake of known location and magnitude. The method utilizes probability distributions from an intensity/ground motion data set along with a ground motion attenuation relation to estimate the ground motion from intensity. The ground motions with the highest probabilities are the ones most likely experienced at the site of the MMI observation. We test the method using MMI/ground motion data from California and published ground motion attenuation relations to estimate the ground motions for several earthquakes: 1999 Hector Mine, California (M7.1); 1988 Saguenay, Quebec (M5.9); and 1982 Gaza, New Hampshire (M4.4). In an example where the method is applied to a historic earthquake, we estimate that the peak ground accelerations associated with the 1727 (M???5.2) earthquake at Newbury, Massachusetts, ranged from 0.23 g at Newbury to 0.06 g at Boston.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Earthquake Spectra","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1193/1.1596549","issn":"87552930","usgsCitation":"Ebel, J., and Wald, D., 2003, Bayesian Estimations of Peak Ground Acceleration and 5% Damped Spectral Acceleration from Modified Mercalli Intensity Data: Earthquake Spectra, v. 19, no. 3, p. 511-529, https://doi.org/10.1193/1.1596549.","startPage":"511","endPage":"529","numberOfPages":"19","costCenters":[],"links":[{"id":208870,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1193/1.1596549"},{"id":234938,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"19","issue":"3","noUsgsAuthors":false,"publicationDate":"2003-08-01","publicationStatus":"PW","scienceBaseUri":"5059f029e4b0c8380cd4a609","contributors":{"authors":[{"text":"Ebel, J.E.","contributorId":54619,"corporation":false,"usgs":true,"family":"Ebel","given":"J.E.","email":"","affiliations":[],"preferred":false,"id":406630,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wald, D.J. 0000-0002-1454-4514","orcid":"https://orcid.org/0000-0002-1454-4514","contributorId":43809,"corporation":false,"usgs":true,"family":"Wald","given":"D.J.","affiliations":[],"preferred":false,"id":406629,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70025797,"text":"70025797 - 2003 - An empirical approach to inversion of an unconventional helicopter electromagnetic dataset","interactions":[],"lastModifiedDate":"2012-03-12T17:20:32","indexId":"70025797","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2165,"text":"Journal of Applied Geophysics","active":true,"publicationSubtype":{"id":10}},"title":"An empirical approach to inversion of an unconventional helicopter electromagnetic dataset","docAbstract":"A helicopter electromagnetic (HEM) survey acquired at the U.S. Idaho National Engineering and Environmental Laboratory (INEEL) used a modification of a traditional mining airborne method flown at low levels for detailed characterization of shallow waste sites. The low sensor height, used to increase resolution, invalidates standard assumptions used in processing HEM data. Although the survey design strategy was sound, traditional interpretation techniques, routinely used in industry, proved ineffective. Processed data and apparent resistivity maps were severely distorted, and hence unusable, due to low flight height effects, high magnetic permeability of the basalt host, and the conductive, three-dimensional nature of the waste site targets.To accommodate these interpretation challenges, we modified a one-dimensional inversion routine to include a linear term in the objective function that allows for the magnetic and three-dimensional electromagnetic responses in the in-phase data. Although somewhat ad hoc, the use of this term in the inverse routine, referred to as the shift factor, was successful in defining the waste sites and reducing noise due to the low flight height and magnetic characteristics of the host rock. Many inversion scenarios were applied to the data and careful analysis was necessary to determine the parameters appropriate for interpretation, hence the approach was empirical. Data from three areas were processed with this scheme to highlight different interpretational aspects of the method. Wastes sites were delineated with the shift terms in two of the areas, allowing for separation of the anthropomorphic targets from the natural one-dimensional host. In the third area, the estimated resistivity and the shift factor were used for geological mapping. The high magnetic content of the native soil enabled the mapping of disturbed soil with the shift term. Published by Elsevier Science B.V.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Applied Geophysics","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0926-9851(03)00011-9","issn":"09269851","usgsCitation":"Pellerin, L., and Labson, V., 2003, An empirical approach to inversion of an unconventional helicopter electromagnetic dataset: Journal of Applied Geophysics, v. 53, no. 1, p. 49-61, https://doi.org/10.1016/S0926-9851(03)00011-9.","startPage":"49","endPage":"61","numberOfPages":"13","costCenters":[],"links":[{"id":208831,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0926-9851(03)00011-9"},{"id":234864,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"53","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ea33e4b0c8380cd486d7","contributors":{"authors":[{"text":"Pellerin, L.","contributorId":94073,"corporation":false,"usgs":true,"family":"Pellerin","given":"L.","email":"","affiliations":[],"preferred":false,"id":406613,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Labson, V.F.","contributorId":20506,"corporation":false,"usgs":true,"family":"Labson","given":"V.F.","email":"","affiliations":[],"preferred":false,"id":406612,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70025794,"text":"70025794 - 2003 - Timing of recent accelerations of Pine Island Glacier, Antarctica","interactions":[],"lastModifiedDate":"2018-11-01T14:28:56","indexId":"70025794","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1807,"text":"Geophysical Research Letters","active":true,"publicationSubtype":{"id":10}},"title":"Timing of recent accelerations of Pine Island Glacier, Antarctica","docAbstract":"We have used Interferometric Synthetic Aperture Radar (InSAR) data and sequential Landsat imagery to identify and temporally constrain two acceleration events on Pine Island Glacier (PIG). These two events are separated by a period of at least seven years (1987 - 1994). The change in discharge between two flux gates indicates that the majority of the increase in discharge associated with the second acceleration originates well inland (>80 km) from the grounding line. An analysis indicates that changes in driving stress consistent with observed thinning rates are sufficient in magnitude to explain much of the acceleration.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geophysical Research Letters","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"American Geophysical Union","doi":"10.1029/2003GL017609","issn":"00948276","usgsCitation":"Joughin, I., Rignot, E., Rosanova, C.E., Lucchitta, B.K., and Bohlander, J., 2003, Timing of recent accelerations of Pine Island Glacier, Antarctica: Geophysical Research Letters, v. 30, no. 13, 4 p., https://doi.org/10.1029/2003GL017609.","productDescription":"4 p.","costCenters":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"links":[{"id":478473,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://escholarship.org/uc/item/00m2p7sb","text":"External Repository"},{"id":234823,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Antarctica","otherGeospatial":"Pine Island Glacier","volume":"30","issue":"13","noUsgsAuthors":false,"publicationDate":"2003-07-11","publicationStatus":"PW","scienceBaseUri":"505bb3f5e4b08c986b3260bd","contributors":{"authors":[{"text":"Joughin, I.","contributorId":105084,"corporation":false,"usgs":true,"family":"Joughin","given":"I.","affiliations":[],"preferred":false,"id":406607,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rignot, Eric","contributorId":34760,"corporation":false,"usgs":true,"family":"Rignot","given":"Eric","email":"","affiliations":[],"preferred":false,"id":406604,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rosanova, Christine E.","contributorId":77239,"corporation":false,"usgs":true,"family":"Rosanova","given":"Christine","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":406605,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Lucchitta, Baerbel K. blucchitta@usgs.gov","contributorId":3649,"corporation":false,"usgs":true,"family":"Lucchitta","given":"Baerbel","email":"blucchitta@usgs.gov","middleInitial":"K.","affiliations":[],"preferred":true,"id":406603,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Bohlander, J.","contributorId":82101,"corporation":false,"usgs":true,"family":"Bohlander","given":"J.","email":"","affiliations":[],"preferred":false,"id":406606,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70025792,"text":"70025792 - 2003 - Hilbert-Huang transform analysis of dynamic and earthquake motion recordings","interactions":[],"lastModifiedDate":"2016-01-25T15:48:04","indexId":"70025792","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2252,"text":"Journal of Engineering Mechanics","active":true,"publicationSubtype":{"id":10}},"title":"Hilbert-Huang transform analysis of dynamic and earthquake motion recordings","docAbstract":"This study examines the rationale of Hilbert-Huang transform (HHT) for analyzing dynamic and earthquake motion recordings in studies of seismology and engineering. In particular, this paper first provides the fundamentals of the HHT method, which consist of the empirical mode decomposition (EMD) and the Hilbert spectral analysis. It then uses the HHT to analyze recordings of hypothetical and real wave motion, the results of which are compared with the results obtained by the Fourier data processing technique. The analysis of the two recordings indicates that the HHT method is able to extract some motion characteristics useful in studies of seismology and engineering, which might not be exposed effectively and efficiently by Fourier data processing technique. Specifically, the study indicates that the decomposed components in EMD of HHT, namely, the intrinsic mode function (IMF) components, contain observable, physical information inherent to the original data. It also shows that the grouped IMF components, namely, the EMD-based low- and high-frequency components, can faithfully capture low-frequency pulse-like as well as high-frequency wave signals. Finally, the study illustrates that the HHT-based Hilbert spectra are able to reveal the temporal-frequency energy distribution for motion recordings precisely and clearly.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Engineering Mechanics","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"American Society of Civil Engineers","publisherLocation":"New York","doi":"10.1061/(ASCE)0733-9399(2003)129:8(861)","issn":"07339399","usgsCitation":"Zhang, R., Ma, S., Safak, E., and Hartzell, S., 2003, Hilbert-Huang transform analysis of dynamic and earthquake motion recordings: Journal of Engineering Mechanics, v. 129, no. 8, p. 861-875, https://doi.org/10.1061/(ASCE)0733-9399(2003)129:8(861).","productDescription":"15 p.","startPage":"861","endPage":"875","numberOfPages":"15","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":300,"text":"Geologic Hazards Science Center","active":true,"usgs":true}],"links":[{"id":234786,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":208790,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1061/(ASCE)0733-9399(2003)129:8(861)"}],"volume":"129","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a314ce4b0c8380cd5dde6","contributors":{"authors":[{"text":"Zhang, R.R.","contributorId":18942,"corporation":false,"usgs":true,"family":"Zhang","given":"R.R.","email":"","affiliations":[],"preferred":false,"id":406598,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ma, S.","contributorId":59189,"corporation":false,"usgs":true,"family":"Ma","given":"S.","email":"","affiliations":[],"preferred":false,"id":406599,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Safak, E.","contributorId":104070,"corporation":false,"usgs":true,"family":"Safak","given":"E.","email":"","affiliations":[],"preferred":false,"id":406600,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hartzell, S.","contributorId":12603,"corporation":false,"usgs":true,"family":"Hartzell","given":"S.","email":"","affiliations":[],"preferred":false,"id":406597,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70025925,"text":"70025925 - 2003 - Using regression methods to estimate stream phosphorus loads at the Illinois River, Arkansas","interactions":[],"lastModifiedDate":"2022-04-08T17:25:41.134531","indexId":"70025925","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":833,"text":"Applied Engineering in Agriculture","active":true,"publicationSubtype":{"id":10}},"title":"Using regression methods to estimate stream phosphorus loads at the Illinois River, Arkansas","docAbstract":"The development of total maximum daily loads (TMDLs) requires evaluating existing constituent loads in streams. Accurate estimates of constituent loads are needed to calibrate watershed and reservoir models for TMDL development. The best approach to estimate constituent loads is high frequency sampling, particularly during storm events, and mass integration of constituents passing a point in a stream. Most often, resources are limited and discrete water quality samples are collected on fixed intervals and sometimes supplemented with directed sampling during storm events. When resources are limited, mass integration is not an accurate means to determine constituent loads and other load estimation techniques such as regression models are used. The objective of this work was to determine a minimum number of water-quality samples needed to provide constituent concentration data adequate to estimate constituent loads at a large stream. Twenty sets of water quality samples with and without supplemental storm samples were randomly selected at various fixed intervals from a database at the Illinois River, northwest Arkansas. The random sets were used to estimate total phosphorus (TP) loads using regression models. The regression-based annual TP loads were compared to the integrated annual TP load estimated using all the data. At a minimum, monthly sampling plus supplemental storm samples (six samples per year) was needed to produce a root mean square error of less than 15%. Water quality samples should be collected at least semi-monthly (every 15 days) in studies less than two years if seasonal time factors are to be used in the regression models. Annual TP loads estimated from independently collected discrete water quality samples further demonstrated the utility of using regression models to estimate annual TP loads in this stream system.","language":"English","publisher":"American Society of Agricultural and Biological Engineers","doi":"10.13031/2013.13110","issn":"08838542","usgsCitation":"Haggard, B., Soerens, T.S., Green, W.R., and Richards, R.P., 2003, Using regression methods to estimate stream phosphorus loads at the Illinois River, Arkansas: Applied Engineering in Agriculture, v. 19, no. 2, p. 187-194, https://doi.org/10.13031/2013.13110.","productDescription":"8 p.","startPage":"187","endPage":"194","costCenters":[],"links":[{"id":234578,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arkansas","otherGeospatial":"Illinois River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": 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E.","contributorId":69755,"corporation":false,"usgs":true,"family":"Haggard","given":"B. E.","affiliations":[],"preferred":false,"id":407122,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Soerens, T. S.","contributorId":53573,"corporation":false,"usgs":true,"family":"Soerens","given":"T.","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":407119,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Green, W. R.","contributorId":68354,"corporation":false,"usgs":true,"family":"Green","given":"W.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":407121,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Richards, R. P.","contributorId":60792,"corporation":false,"usgs":true,"family":"Richards","given":"R.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":407120,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70025926,"text":"70025926 - 2003 - An empirical model for earthquake probabilities in the San Francisco Bay region, California, 2002-2031","interactions":[],"lastModifiedDate":"2023-10-17T00:58:00.370015","indexId":"70025926","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","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":"An empirical model for earthquake probabilities in the San Francisco Bay region, California, 2002-2031","docAbstract":"The moment magnitude M 7.8 earthquake in 1906 profoundly changed the rate of seismic activity over much of northern California. The low rate of seismic activity in the San Francisco Bay region (SFBR) since 1906, relative to that of the preceding 55 yr, is often explained as a stress-shadow effect of the 1906 earthquake. However, existing elastic and visco-elastic models of stress change fail to fully account for the duration of the lowered rate of earthquake activity. We use variations in the rate of earthquakes as a basis for a simple empirical model for estimating the probability of M ≥6.7 earthquakes in the SFBR. The model preserves the relative magnitude distribution of sources predicted by the Working Group on California Earthquake Probabilities' (WGCEP, 1999; WGCEP, 2002) model of characterized ruptures on SFBR faults and is consistent with the occurrence of the four M ≥6.7 earthquakes in the region since 1838. When the empirical model is extrapolated 30 yr forward from 2002, it gives a probability of 0.42 for one or more M ≥6.7 in the SFBR. This result is lower than the probability of 0.5 estimated by WGCEP (1988), lower than the 30-yr Poisson probability of 0.60 obtained by WGCEP (1999) and WGCEP (2002), and lower than the 30-yr time-dependent probabilities of 0.67, 0.70, and 0.63 obtained by WGCEP (1990), WGCEP (1999), and WGCEP (2002), respectively, for the occurrence of one or more large earthquakes. This lower probability is consistent with the lack of adequate accounting for the 1906 stress-shadow in these earlier reports. The empirical model represents one possible approach toward accounting for the stress-shadow effect of the 1906 earthquake. However, the discrepancy between our result and those obtained with other modeling methods underscores the fact that the physics controlling the timing of earthquakes is not well understood. Hence, we advise against using the empirical model alone (or any other single probability model) for estimating the earthquake hazard and endorse the use of all credible earthquake probability models for the region, including the empirical model, with appropriate weighting, as was done in WGCEP (2002).
We consider expected relationships between apparent stress τa and static stress drop Δτs using a standard energy balance and find τa = Δτs (0.5 - ξ), where ξ is stress overshoot. A simple implementation of this balance is to assume overshoot is constant; then apparent stress should vary linearly with stress drop, consistent with spectral theories (Brune, 1970) and dynamic crack models (Madariaga, 1976). Normalizing this expression by the static stress drop defines an efficiency ηsw = τsa/Δτs as follows from Savage and Wood (1971). We use this measure of efficiency to analyze data from one of a number of observational studies that find apparent stress to increase with seismic moment, namely earthquakes recorded in the Cajon Pass borehole by Abercrombie (1995). Increases in apparent stress with event size could reflect an increase in seismic efficiency; however, ηsw for the Cajon earthquakes shows no such increase and is approximately constant over the entire moment range. Thus, apparent stress and stress drop co-vary, as expected from the energy balance at constant overshoot. The median value of ηsw for the Cajon earthquakes is four times lower than ηsw for laboratory events. Thus, these Cajon-recorded earthquakes have relatively low and approximately constant efficiency. As the energy balance requires ηsw = 0.5 - ξ, overshoot can be estimated directly from the Savage-Wood efficiency; overshoot is positive for Cajon Pass earthquakes. Variations in apparent stress with seismic moment for these earthquakes result primarily from systematic variations in static stress drop with seismic moment and do not require a relative decrease in sliding resistance with increasing event size (dynamic weakening). Based on the comparison of field and lab determinations of the Savage-Wood efficiency, we suggest the criterion ηsw > 0.3 as a test for dynamic weakening in excess of that seen in the lab.
We develop a parameterization of the beta-binomial mixture that provides sensible inferences about the size of a closed population when probabilities of capture or detection vary among individuals. Three classes of mixture models (beta-binomial, logistic-normal, and latent-class) are fitted to recaptures of snowshoe hares for estimating abundance and to counts of bird species for estimating species richness. In both sets of data, rates of detection appear to vary more among individuals (animals or species) than among sampling occasions or locations. The estimates of population size and species richness are sensitive to model-specific assumptions about the latent distribution of individual rates of detection. We demonstrate using simulation experiments that conventional diagnostics for assessing model adequacy, such as deviance, cannot be relied on for selecting classes of mixture models that produce valid inferences about population size. Prior knowledge about sources of individual heterogeneity in detection rates, if available, should be used to help select among classes of mixture models that are to be used for inference.
","language":"English","publisher":"Wiley","doi":"10.1111/1541-0420.00042","issn":"0006341X","usgsCitation":"Dorazio, R., and Royle, J., 2003, Mixture models for estimating the size of a closed population when capture rates vary among individuals: Biometrics, v. 59, no. 2, p. 351-364, https://doi.org/10.1111/1541-0420.00042.","productDescription":"14 p.","startPage":"351","endPage":"364","costCenters":[],"links":[{"id":387235,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"59","issue":"2","noUsgsAuthors":false,"publicationDate":"2003-06-11","publicationStatus":"PW","scienceBaseUri":"505a5b8ae4b0c8380cd6f61b","contributors":{"authors":[{"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":405457,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Royle, J. Andrew 0000-0003-3135-2167","orcid":"https://orcid.org/0000-0003-3135-2167","contributorId":96221,"corporation":false,"usgs":true,"family":"Royle","given":"J. Andrew","affiliations":[],"preferred":false,"id":405458,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70025931,"text":"70025931 - 2003 - Mapping vegetation in Yellowstone National Park using spectral feature analysis of AVIRIS data","interactions":[],"lastModifiedDate":"2018-05-03T15:50:11","indexId":"70025931","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3254,"text":"Remote Sensing of Environment","printIssn":"0034-4257","active":true,"publicationSubtype":{"id":10}},"title":"Mapping vegetation in Yellowstone National Park using spectral feature analysis of AVIRIS data","docAbstract":"Knowledge of the distribution of vegetation on the landscape can be used to investigate ecosystem functioning. The sizes and movements of animal populations can be linked to resources provided by different plant species. This paper demonstrates the application of imaging spectroscopy to the study of vegetation in Yellowstone National Park (Yellowstone) using spectral feature analysis of data from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). AVIRIS data, acquired on August 7, 1996, were calibrated to surface reflectance using a radiative transfer model and field reflectance measurements of a ground calibration site. A spectral library of canopy reflectance signatures was created by averaging pixels of the calibrated AVIRIS data over areas of known forest and nonforest vegetation cover types in Yellowstone. Using continuum removal and least squares fitting algorithms in the US Geological Survey's Tetracorder expert system, the distributions of these vegetation types were determined by comparing the absorption features of vegetation in the spectral library with the spectra from the AVIRIS data. The 0.68 μm chlorophyll absorption feature and leaf water absorption features, centered near 0.98 and 1.20 μm, were analyzed. Nonforest cover types of sagebrush, grasslands, willows, sedges, and other wetland vegetation were mapped in the Lamar Valley of Yellowstone. Conifer cover types of lodgepole pine, whitebark pine, Douglas fir, and mixed Engelmann spruce/subalpine fir forests were spectrally discriminated and their distributions mapped in the AVIRIS images. In the Mount Washburn area of Yellowstone, a comparison of the AVIRIS map of forest cover types to a map derived from air photos resulted in an overall agreement of 74.1% (kappa statistic=0.62).
Bobjonesite, V4+ O (SO4) (H2O)3, is a new mineral species from Temple Mountain, Emery County, Utah, U.S.A. It occurs as blue-green crusts and efflorescences in fractures in a fossil (Triassic) tree; individual crystals are <<1 mm and are intimately intergrown. Bobjonesite hydrates very easily, and is unstable in all but the driest atmosphere. Its structure was determined on a crystal of bobjonesite; however, the physical properties, optical properties and X-ray powder-diffraction pattern were recorded on the synthetic equivalent, and an electron-microprobe analysis was not possible. Bobjonesite has a pale blue streak, a vitreous luster and no observable fluorescence under ultraviolet light. It has no cleavage or parting. The Mohs hardness is ~1, and the calculated density is 2.28 g/cm3. Bobjonesite is biaxial positive, with α 1.555(2), β 1.561(1), γ 1.574(2), 2V(obs.) = 72(1)°, 2V(calc.) = 69°; it is non-pleochroic, X = b, Y ≈ a, Z ∧ c ≈ 19° (in β obtuse). Bobjonesite is monoclinic, space group P21/n, cell dimensions from single-crystal data: a 7.3940(5), b 7.4111(3), c 12.0597(9) Å, β 106.55(1)°, V 633.5(1) Å3, Z = 4. The strongest seven lines in the X-ray powder-diffraction pattern [d in Å(I)(hkl)] are as follows: 5.795(100)(002), 3.498(90)(112), 3.881(48)(1̅03), 5.408(37) (101), 4.571(20)(012), 6.962(11)(1̅01) and 6.254(11)(011). The chemical formula was derived from crystal-structure analysis; the end-member formula is V O (SO4) (H2O)3. The crystal structure of bobjonesite was refined to an R index of 3.6% for 1105 observed (| Fo | > 5>F) reflections measured with an automated four-circle X-ray diffractometer using MoKα X-radiation. There is one V site occupied by V4+ and surrounded by three O atoms and three (H2O) groups in an octahedral arrangement, with one short vanadyl bond (1.577 Å), four similar equatorial bonds (<2.022 Å>), and one longer V–O bond (2.278 Å) trans to the vanadyl bond. The structure consists of isolated [V4+2 O2 (H2O)6 (SO4)2] clusters linked by hydrogen bonds.
Distant as well as local earthquakes have induced groundwater-level changes persisting for days to weeks at Long Valley caldera, California. Four wells open to formations as deep as 300 m have responded to 16 earthquakes, and responses to two earthquakes in the 3-km-deep Long Valley Exploratory Well (LVEW) show that these changes are not limited to weathered or unconsolidated near-surface rocks. All five wells exhibit water-level variations in response to earth tides, indicating they can be used as low-resolution strainmeters. Earthquakes induce gradual water-level changes that increase in amplitude for as long as 30 days, then return more slowly to pre-earthquake levels. The gradual water-level changes are always drops at wells LKT, LVEW, and CH-10B, and always rises at well CW-3. At a dilatometer just outside the caldera, earthquake-induced strain responses consist of either a step followed by a contractional strain-rate increase, or a transient contractional signal that reaches a maximum in about seven days and then returns toward the pre-earthquake value. The sizes of the gradual water-level changes generally increase with earthquake magnitude and decrease with hypocentral distance. Local earthquakes in Long Valley produce coseismic water-level steps; otherwise the responses to local earthquakes and distant earthquakes are indistinguishable. In particular, water-level and strain changes in Long Valley following the 1992 M7.3 Landers earthquake, 450 km distant, closely resemble those initiated by a M4.9 local earthquake on November 22, 1997, during a seismic swarm with features indicative of fluid involvement. At the LKT well, many of the response time histories are identical for 20 days after each earthquake, and can be matched by a theoretical solution giving the pore pressure as a function of time due to diffusion of a nearby, instantaneous, pressure drop. Such pressure drops could be produced by accelerated inflation of the resurgent dome by amounts too small to be detected by the two-color electronic distance-measuring network. Opening-mode displacement in the south moat, inferred to have followed a M4.9 earthquake on November 22, 1997, could also create extensional strain on the dome and lead to water-level changes similar to those following dome inflation. Contractional strain that could account for earthquake-induced water-level rises at the CW-3 well is inconsistent with geodetic observations. We instead attribute these water-level rises to diffusion of elevated fluid pressure localized in the south moat thermal aquifer. For hydraulic diffusivities appropriate to the upper few hundred meters at Long Valley, an influx of material at temperatures of 300°C can thermally generate pressure of 6 m of water or more, an order of magnitude larger than needed to account for the CW-3 water-level rises. If magma or hot aqueous fluid rises to within 1 km of the surface in the eastern part of the south moat, then hydraulic diffusivities are high enough to allow fluid pressure to propagate to CW-3 on the time scale observed. The data indicate that seismic waves from large distant earthquakes can stimulate upward movement of fluid in the hydrothermal system at Long Valley.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0377-0273(03)00173-2","issn":"03770273","usgsCitation":"Roeloffs, E.A., Sneed, M., Galloway, D.L., Sorey, M.L., Farrar, C.D., Howle, J.F., and Hughes, J., 2003, Water-level changes induced by local and distant earthquakes at Long Valley caldera, California: Journal of Volcanology and Geothermal Research, v. p., no. 3-4, p. 269-303, https://doi.org/10.1016/S0377-0273(03)00173-2.","productDescription":"35 p.","startPage":"269","endPage":"303","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":35860,"text":"Ohio-Kentucky-Indiana Water Science Center","active":true,"usgs":true}],"links":[{"id":236122,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":209543,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0377-0273(03)00173-2"}],"country":"United States","state":"California","otherGeospatial":"Long Valley Caldera","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -118.93936157226562,\n 37.78645343442073\n ],\n [\n -119.10621643066408,\n 37.709899354855125\n ],\n [\n -119.04579162597656,\n 37.61477533148087\n ],\n [\n -118.82469177246095,\n 37.591383348725785\n ],\n [\n -118.62213134765626,\n 37.61586315165877\n ],\n [\n -118.64479064941406,\n 37.67729913640425\n ],\n [\n -118.71551513671876,\n 37.759858513184625\n ],\n [\n -118.93936157226562,\n 37.78645343442073\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"p.","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bcd50e4b08c986b32dfbd","contributors":{"authors":[{"text":"Roeloffs, Evelyn A. 0000-0002-4761-0469 evelynr@usgs.gov","orcid":"https://orcid.org/0000-0002-4761-0469","contributorId":2680,"corporation":false,"usgs":true,"family":"Roeloffs","given":"Evelyn","email":"evelynr@usgs.gov","middleInitial":"A.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true},{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"preferred":true,"id":405470,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sneed, Michelle 0000-0002-8180-382X micsneed@usgs.gov","orcid":"https://orcid.org/0000-0002-8180-382X","contributorId":155,"corporation":false,"usgs":true,"family":"Sneed","given":"Michelle","email":"micsneed@usgs.gov","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":405471,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Galloway, Devin L. 0000-0003-0904-5355 dlgallow@usgs.gov","orcid":"https://orcid.org/0000-0003-0904-5355","contributorId":679,"corporation":false,"usgs":true,"family":"Galloway","given":"Devin","email":"dlgallow@usgs.gov","middleInitial":"L.","affiliations":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":5078,"text":"Southwest Regional Director's Office","active":true,"usgs":true},{"id":35860,"text":"Ohio-Kentucky-Indiana Water Science Center","active":true,"usgs":true},{"id":509,"text":"Office of the Associate Director for Water","active":true,"usgs":true},{"id":5058,"text":"Office of the Chief Scientist for Water","active":true,"usgs":true}],"preferred":true,"id":405472,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Sorey, Michael L.","contributorId":20726,"corporation":false,"usgs":true,"family":"Sorey","given":"Michael","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":405475,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Farrar, Christopher D. cdfarrar@usgs.gov","contributorId":1501,"corporation":false,"usgs":true,"family":"Farrar","given":"Christopher","email":"cdfarrar@usgs.gov","middleInitial":"D.","affiliations":[],"preferred":true,"id":405474,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Howle, James F. 0000-0003-0491-6203 jfhowle@usgs.gov","orcid":"https://orcid.org/0000-0003-0491-6203","contributorId":2225,"corporation":false,"usgs":true,"family":"Howle","given":"James","email":"jfhowle@usgs.gov","middleInitial":"F.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":405473,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Hughes, J.","contributorId":83725,"corporation":false,"usgs":true,"family":"Hughes","given":"J.","affiliations":[],"preferred":false,"id":405476,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70025534,"text":"70025534 - 2003 - The mechanics of unrest at Long Valley caldera, California. 2. Constraining the nature of the source using geodetic and micro-gravity data","interactions":[],"lastModifiedDate":"2012-03-12T17:20:26","indexId":"70025534","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2499,"text":"Journal of Volcanology and Geothermal Research","active":true,"publicationSubtype":{"id":10}},"title":"The mechanics of unrest at Long Valley caldera, California. 2. Constraining the nature of the source using geodetic and micro-gravity data","docAbstract":"We model the source of inflation of Long Valley caldera by combining geodetic and micro-gravity data. Uplift from GPS and leveling, two-color EDM measurements, and residual gravity change determinations are used to estimate the intrusion geometry, assuming a vertical prolate ellipsoidal source. The U.S. Geological Survey occupied the Long Valley gravity network six times from 1980 to 1985. We reoccupied this network twice, in the summer of 1998 (33 stations), and the summer of 1999 (37 stations). Before gravity data can be used to estimate the density of the intrusion, they must be corrected for the effect of vertical deformation (the free-air effect) and changes in the water table. We use geostatistical techniques to interpolate uplift and water table changes at the gravity stations. The inflation source (a vertical prolate ellipsoid) is located 5.9 km beneath the resurgent dome with an aspect ratio equal to 0.475, a volume change from 1982 to 1999 of 0.136 km3 and a density of around 1700 kg/m3. A bootstrap method was employed to estimate 95% confidence bounds for the parameters of the inflation model. We obtained a range of 0.105-0.187 km3 for the volume change, and 1180-2330 kg/m3 for the density. Our results do not support hydrothermal fluid intrusion as the primary cause of unrest, and confirm the intrusion of silicic magma beneath Long Valley caldera. Failure to account for the ellipsoidal nature of the source biases the estimated source depth by 2.9 km (a 33% increase), the volume change by 0.019 km3 (a 14% increase) and the density by about 1200 kg/m3 (a 40% increase). ?? 2003 Elsevier B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Volcanology and Geothermal Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0377-0273(03)00171-9","issn":"03770273","usgsCitation":"Battaglia, M., Segall, P., and Roberts, C., 2003, The mechanics of unrest at Long Valley caldera, California. 2. Constraining the nature of the source using geodetic and micro-gravity data: Journal of Volcanology and Geothermal Research, v. 127, no. 3-4, p. 219-245, https://doi.org/10.1016/S0377-0273(03)00171-9.","startPage":"219","endPage":"245","numberOfPages":"27","costCenters":[],"links":[{"id":209431,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0377-0273(03)00171-9"},{"id":235866,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"127","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505badc5e4b08c986b323ddc","contributors":{"authors":[{"text":"Battaglia, Maurizio","contributorId":32602,"corporation":false,"usgs":true,"family":"Battaglia","given":"Maurizio","affiliations":[],"preferred":false,"id":405549,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Segall, P.","contributorId":44231,"corporation":false,"usgs":false,"family":"Segall","given":"P.","affiliations":[],"preferred":false,"id":405550,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Roberts, C.","contributorId":28210,"corporation":false,"usgs":true,"family":"Roberts","given":"C.","affiliations":[],"preferred":false,"id":405548,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70025410,"text":"70025410 - 2003 - Habitat selection of the channel darter, Percina (Cottogaster) copelandi, a surrogate for the imperiled pearl darter, Percina aurora","interactions":[],"lastModifiedDate":"2017-09-13T16:26:30","indexId":"70025410","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2299,"text":"Journal of Freshwater Ecology","active":true,"publicationSubtype":{"id":10}},"displayTitle":"Habitat selection of the channel darter, Percina (Cottogaster) copelandi, a surrogate for the imperiled pearl darter, Percina aurora","title":"Habitat selection of the channel darter, Percina (Cottogaster) copelandi, a surrogate for the imperiled pearl darter, Percina aurora","docAbstract":"Percina (Cottogaster) aurora is an imperiled species under consideration for listing by the U.S. Fish and Wildlife Service. To better understand habitat use of P. aurora, we studied a related and more abundant Cottogasterspecies, Percina copelandi, from the Ouachita River, Arkansas. We used a laboratory stream system to examine mesohabitat selection (pools versus riffles) and microhabitat selection (substratum particle size) of P. copelandi over three temperature regimes (summer, spring, and winter). Percina copelandi selected pool habitats over riffles and selected pools with coarse substrata (e.g., cobble) over fine substrata (e.g., gravel). In riffles, P. copelandi selected large substrata during winter and spring but did not show particle size selection during summer. These data, and various published and unpublished field data for P. aurora, suggest that habitat use of P. aurora is also centered around deep runs and pools, with large substrata likely being more important at low water temperatures.
","language":"English","publisher":"Taylor and Francis","doi":"10.1080/02705060.2003.9664491","issn":"02705060","usgsCitation":"Schofield, P., and Ross, S.T., 2003, Habitat selection of the channel darter, Percina (Cottogaster) copelandi, a surrogate for the imperiled pearl darter, Percina aurora: Journal of Freshwater Ecology, v. 18, no. 2, p. 249-257, https://doi.org/10.1080/02705060.2003.9664491.","productDescription":"9 p.","startPage":"249","endPage":"257","costCenters":[],"links":[{"id":235665,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"18","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2f27e4b0c8380cd5cb2f","contributors":{"authors":[{"text":"Schofield, Pamela J. 0000-0002-8752-2797 pschofield@usgs.gov","orcid":"https://orcid.org/0000-0002-8752-2797","contributorId":138883,"corporation":false,"usgs":true,"family":"Schofield","given":"Pamela J.","email":"pschofield@usgs.gov","affiliations":[{"id":566,"text":"Southeast Ecological Science Center","active":true,"usgs":true}],"preferred":false,"id":405066,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ross, Stephen T.","contributorId":64111,"corporation":false,"usgs":true,"family":"Ross","given":"Stephen","email":"","middleInitial":"T.","affiliations":[{"id":12981,"text":"Department of Biological Sciences, University of Southern Mississippi","active":true,"usgs":false}],"preferred":false,"id":405065,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70025536,"text":"70025536 - 2003 - Structure and mechanics of the Hayward-Rodgers Creek Fault step-over, San Francisco Bay, California","interactions":[],"lastModifiedDate":"2021-07-26T14:15:06.716598","indexId":"70025536","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","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":"Structure and mechanics of the Hayward-Rodgers Creek Fault step-over, San Francisco Bay, California","docAbstract":"A dilatational step-over between the right-lateral Hayward and Rodgers Creek faults lies beneath San Pablo Bay in the San Francisco Bay area. A key seismic hazard issue is whether an earthquake on one of the faults could rupture through the step-over, enhancing its maximum possible magnitude. If ruptures are terminated at the step-over, then another important issue is how strain transfers through the step. We developed a combined seismic reflection and refraction cross section across south San Pablo Bay and found that the Hayward and Rodgers Creek faults converge to within 4 km of one another near the surface, about 2 km closer than previously thought. Interpretation of potential field data from San Pablo Bay indicated a low likelihood of strike-slip transfer faults connecting the Hayward and Rodgers Creek faults. Numerical simulations suggest that it is possible for a rupture to jump across a 4-km fault gap, although special stressing conditions are probably required (e.g., Harris and Day, 1993, 1999). Slip on the Hayward and Rodgers Creek faults is building an extensional pull-apart basin that could contain hazardous normal faults. We investigated strain in the pull-apart using a finite-element model and calculated a ∼0.02-MPa/yr differential stressing rate in the step-over on a least-principal-stress orientation nearly parallel to the strike-slip faults where they overlap. A 1- to 10-MPa stress-drop extensional earthquake is expected on normal faults oriented perpendicular to the strike-slip faults every 50-500 years. The last such earthquake might have been the 1898 M 6.0-6.5 shock in San Pablo Bay that apparently produced a small tsunami. Historical hydrographic surveys gathered before and after 1898 indicate abnormal subsidence of the bay floor within the step-over, possibly related to the earthquake. We used a hydrodynamic model to show that a dip-slip mechanism in north San Pablo Bay is the most likely 1898 rupture scenario to have caused the tsunami. While we find no strike-slip transfer fault between the Hayward and Rodgers Creek faults, a normal-fault link could enable through-going segmented rupture of both strike-slip faults and may pose an independent hazard of M ∼6 earthquakes like the 1898 event.
","language":"English","publisher":"Seismological Society of America","doi":"10.1785/0120020228","issn":"00371106","usgsCitation":"Parsons, T., Sliter, R., Geist, E., Jachens, R., Jaffe, B.E., Foxgrover, A., Hart, P., and McCarthy, J., 2003, Structure and mechanics of the Hayward-Rodgers Creek Fault step-over, San Francisco Bay, California: Bulletin of the Seismological Society of America, v. 93, no. 5, p. 2187-2200, https://doi.org/10.1785/0120020228.","productDescription":"14 p.","startPage":"2187","endPage":"2200","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":387417,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","city":"San Francisco","otherGeospatial":"San Francisco Bay","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -123.11279296875001,\n 37.10776507118514\n ],\n [\n -121.77246093750001,\n 37.10776507118514\n ],\n [\n -121.77246093750001,\n 38.58252615935333\n ],\n [\n -123.11279296875001,\n 38.58252615935333\n ],\n [\n -123.11279296875001,\n 37.10776507118514\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"93","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9c14e4b08c986b31d27a","contributors":{"authors":[{"text":"Parsons, T.","contributorId":48288,"corporation":false,"usgs":true,"family":"Parsons","given":"T.","email":"","affiliations":[],"preferred":false,"id":405555,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sliter, R.","contributorId":66311,"corporation":false,"usgs":true,"family":"Sliter","given":"R.","affiliations":[],"preferred":false,"id":405558,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Geist, E.L. 0000-0003-0611-1150","orcid":"https://orcid.org/0000-0003-0611-1150","contributorId":71993,"corporation":false,"usgs":true,"family":"Geist","given":"E.L.","affiliations":[],"preferred":false,"id":405559,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Jachens, R.C.","contributorId":55433,"corporation":false,"usgs":true,"family":"Jachens","given":"R.C.","email":"","affiliations":[],"preferred":false,"id":405557,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Jaffe, B. E.","contributorId":88327,"corporation":false,"usgs":true,"family":"Jaffe","given":"B.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":405561,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Foxgrover, A.","contributorId":80477,"corporation":false,"usgs":true,"family":"Foxgrover","given":"A.","email":"","affiliations":[],"preferred":false,"id":405560,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Hart, P. E.","contributorId":10773,"corporation":false,"usgs":true,"family":"Hart","given":"P. E.","affiliations":[],"preferred":false,"id":405554,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"McCarthy, J.","contributorId":50290,"corporation":false,"usgs":true,"family":"McCarthy","given":"J.","affiliations":[],"preferred":false,"id":405556,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}} ,{"id":70025537,"text":"70025537 - 2003 - Relationships between metabolic rate, muscle electromyograms and swim performance of adult chinook salmon","interactions":[],"lastModifiedDate":"2016-04-28T15:13:56","indexId":"70025537","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2285,"text":"Journal of Fish Biology","active":true,"publicationSubtype":{"id":10}},"title":"Relationships between metabolic rate, muscle electromyograms and swim performance of adult chinook salmon","docAbstract":"Oxygen consumption rates of adult spring chinook salmon Oncorhynchus tshawytscha increased with swim speed and, depending on temperature and fish mass, ranged from 609 mg O2 h-1 at 30 cm s-1 (c. 0.5 BLs-1) to 3347 mg O2 h-1 at 170 cm s -1 (c. 2.3 BLs-1). Corrected for fish mass, these values ranged from 122 to 670 mg O2 kg-1 h-1, and were similar to other Oncorhynchus species. At all temperatures (8, 12.5 and 17??C), maximum oxygen consumption values levelled off and slightly declined with increasing swim speed >170 cm s-1, and a third-order polynomial regression model fitted the data best. The upper critical swim speed (Ucrit) of fish tested at two laboratories averaged 155 cm s -1 (2.1 BLs-1), but Ucrit of fish tested at the Pacific Northwest National Laboratory were significantly higher (mean 165 cm s-1) than those from fish tested at the Columbia River Research Laboratory (mean 140 cm s-1). Swim trials using fish that had electromyogram (EMG) transmitters implanted in them suggested that at a swim speed of c. 135 cm s-1, red muscle EMG pulse rates slowed and white muscle EMG pulse rates increased. Although there was significant variation between individual fish, this swim speed was c. 80% of the Ucrit for the fish used in the EMG trials (mean Ucrit 168.2 cm s-1). Bioenergetic modelling of the upstream migration of adult chinook salmon should consider incorporating an anaerobic fraction of the energy budget when swim speeds are ???80% of the Ucrit. ?? 2003 The Fisheries Society of the British Isles.
","language":"English","publisher":"Wiley","doi":"10.1046/j.1095-8649.2003.00217.x","issn":"00221112","usgsCitation":"Geist, D., Brown, R., Cullinan, V., Mesa, M., VanderKooi, S.P., and McKinstry, C., 2003, Relationships between metabolic rate, muscle electromyograms and swim performance of adult chinook salmon: Journal of Fish Biology, v. 63, no. 4, p. 970-989, https://doi.org/10.1046/j.1095-8649.2003.00217.x.","productDescription":"20 p.","startPage":"970","endPage":"989","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":654,"text":"Western Fisheries Research Center","active":true,"usgs":true}],"links":[{"id":235904,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":209448,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1046/j.1095-8649.2003.00217.x"}],"volume":"63","issue":"4","noUsgsAuthors":false,"publicationDate":"2003-09-26","publicationStatus":"PW","scienceBaseUri":"50e4a7a8e4b0e8fec6cdc52c","contributors":{"authors":[{"text":"Geist, D.R.","contributorId":45091,"corporation":false,"usgs":true,"family":"Geist","given":"D.R.","email":"","affiliations":[],"preferred":false,"id":405564,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Brown, R.S.","contributorId":68084,"corporation":false,"usgs":true,"family":"Brown","given":"R.S.","email":"","affiliations":[],"preferred":false,"id":405566,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Cullinan, V.I.","contributorId":51078,"corporation":false,"usgs":true,"family":"Cullinan","given":"V.I.","email":"","affiliations":[],"preferred":false,"id":405565,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Mesa, M.G.","contributorId":17386,"corporation":false,"usgs":true,"family":"Mesa","given":"M.G.","email":"","affiliations":[],"preferred":false,"id":405563,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"VanderKooi, S. P.","contributorId":12587,"corporation":false,"usgs":true,"family":"VanderKooi","given":"S.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":405562,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"McKinstry, C.A.","contributorId":90093,"corporation":false,"usgs":true,"family":"McKinstry","given":"C.A.","email":"","affiliations":[],"preferred":false,"id":405567,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70025868,"text":"70025868 - 2003 - Development of hardwood seed zones for Tennessee using a geographic information system","interactions":[],"lastModifiedDate":"2021-08-22T19:40:47.846942","indexId":"70025868","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3447,"text":"Southern Journal of Applied Forestry","active":true,"publicationSubtype":{"id":10}},"title":"Development of hardwood seed zones for Tennessee using a geographic information system","docAbstract":"For species that have no or limited information on genetic variation and adaptability to nonnative sites, there is a need for seed collection guidelines based on biological, climatological, and/or geographical criteria. Twenty-eight hardwood species are currently grown for reforestation purposes at the East Tennessee State Nursery. The majority of these species have had no genetic testing to define guidelines for seed collection location and can be distributed to sites that have a very different environment than that of seed origin(s). Poor survival and/or growth may result if seedlings are not adapted to environmental conditions at the planting location. To address this problem, 30 yr of Tennessee county precipitation and minimum temperature data were analyzed and grouped using a centroid hierarchical cluster analysis. The weather data and elevational data were entered into a Geographic Information System (GIS) and separately layered over Bailey's Ecoregions to develop a seed zone system for Tennessee. The seed zones can be used as a practical guideline for collecting seeds to ensure that the resulting seedlings will be adapted to planting environments.
","language":"English","publisher":"Oxford","doi":"10.1093/sjaf/27.3.172","issn":"01484419","usgsCitation":"Post, L., Schlarbaum, S., Van Manen, F., Cecich, R., Saxton, A., and Schneider, J., 2003, Development of hardwood seed zones for Tennessee using a geographic information system: Southern Journal of Applied Forestry, v. 27, no. 3, p. 172-175, https://doi.org/10.1093/sjaf/27.3.172.","productDescription":"4 p.","startPage":"172","endPage":"175","costCenters":[],"links":[{"id":478500,"rank":0,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1093/sjaf/27.3.172","text":"Publisher Index Page"},{"id":388337,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Tennessee","otherGeospatial":"East Tennessee Nursery","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -84.53704833984375,\n 35.3425748600064\n ],\n [\n -84.47113037109375,\n 35.3425748600064\n ],\n [\n -84.47113037109375,\n 35.39352808136067\n ],\n [\n -84.53704833984375,\n 35.39352808136067\n ],\n [\n -84.53704833984375,\n 35.3425748600064\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"27","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0058e4b0c8380cd4f6f0","contributors":{"authors":[{"text":"Post, L.S.","contributorId":80873,"corporation":false,"usgs":true,"family":"Post","given":"L.S.","email":"","affiliations":[],"preferred":false,"id":406884,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Schlarbaum, S.E.","contributorId":18943,"corporation":false,"usgs":true,"family":"Schlarbaum","given":"S.E.","affiliations":[],"preferred":false,"id":406881,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Van Manen, F.","contributorId":25329,"corporation":false,"usgs":true,"family":"Van Manen","given":"F.","email":"","affiliations":[],"preferred":false,"id":406882,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Cecich, R.A.","contributorId":84958,"corporation":false,"usgs":true,"family":"Cecich","given":"R.A.","email":"","affiliations":[],"preferred":false,"id":406885,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Saxton, A.M.","contributorId":36341,"corporation":false,"usgs":true,"family":"Saxton","given":"A.M.","email":"","affiliations":[],"preferred":false,"id":406883,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Schneider, J.F.","contributorId":16200,"corporation":false,"usgs":true,"family":"Schneider","given":"J.F.","email":"","affiliations":[],"preferred":false,"id":406880,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ]}