Mid- to late-Holocene vegetation change from a remote high-desert site was reconstructed using plant macrofossils and pollen from 9 packrat middens ranging from 0 to 5400 yr in age. Presettlement middens consistently contained abundant macrofossils of plant species palatable to large herbivores that are now absent or reduced, such as winterfat (Ceratoides lanatd) and ricegrass (Stipa hymenoides). Macrofossils and pollen of pinyon pine (Pinus edulis), sagebrush (Artemisia spp.), and roundleaf buffaloberry (Shepherdia rotundifolia) were also recently reduced to their lowest levels for the 5400-yr record. Conversely, species typical of overgrazed range, such as snakeweed (Gutierrezia sarothrae), viscid rabbitbrush (Chrysothamnus visidiflorus), and Russian thistle (Salsola sp.), were not recorded prior to the historic introduction of grazing animals. Pollen of Utah juniper (Juniperus osteosperma) also increased during the last 200 yr. These records demonstrate that the most severe vegetation changes of the last 5400 yr occurred during the past 200 yr. The nature and timing of these changes suggest that they were primarily caused by 19th-century open-land sheep and cattle ranching. The reduction of pinyon and sagebrush concurrent with other grazing impacts suggests that effects of cattle grazing at modern stocking levels may be a poor analog for the effects of intense sheep grazing during drought.
","language":"English","publisher":"Monte L. Bean Life Science Museum, Brigham Young University","usgsCitation":"Cole, K., Henderson, N., and Shafer, D., 1997, Holocene vegetation and historic grazing impacts at Capitol Reef National Park reconstructed using packrat middens: Great Basin Naturalist, v. 57, no. 4, p. 315-326.","productDescription":"12 p.","startPage":"315","endPage":"326","costCenters":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true}],"links":[{"id":133489,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":349034,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://www.jstor.org/stable/41713018"}],"volume":"57","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a54e4b07f02db62bf2f","contributors":{"authors":[{"text":"Cole, K.L.","contributorId":87507,"corporation":false,"usgs":true,"family":"Cole","given":"K.L.","email":"","affiliations":[],"preferred":false,"id":323202,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Henderson, N.","contributorId":50120,"corporation":false,"usgs":true,"family":"Henderson","given":"N.","email":"","affiliations":[],"preferred":false,"id":323201,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Shafer, D.S.","contributorId":15573,"corporation":false,"usgs":true,"family":"Shafer","given":"D.S.","email":"","affiliations":[],"preferred":false,"id":323200,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70185275,"text":"70185275 - 1997 - Analysis of the Cape Cod tracer data","interactions":[],"lastModifiedDate":"2018-03-15T10:39:57","indexId":"70185275","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","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":"Analysis of the Cape Cod tracer data","docAbstract":"An analysis of the Cape Cod test was performed using several first- and higher-order theoretical models. We compare conditional and unconditional solutions of the transport equation and employ them for analysis of the experimental data. We consider spatial moments, mass breakthrough curves, and the distribution of the solute mass in space. The concentration measurements were also analyzed using theoretical models for the expected value and variance of concentration. The theoretical models we employed are based on the spatial correlation structure of the conductivity field, without any fitting of parameters to the tracer data, and hence we can test the predictive power of the theories tested. The effects of recharge on macrodispersion are investigated, and it is shown that recharge provides a reasonable explanation for the enhanced lateral spread of the Cape Cod plume. The compendium of the experimental results presented here is useful for testing of theoretical and numerical models.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/96WR02586","usgsCitation":"Ezzedine, S., and Rubin, Y., 1997, Analysis of the Cape Cod tracer data: Water Resources Research, v. 33, no. 1, p. 1-11, https://doi.org/10.1029/96WR02586.","productDescription":"11 p. ","startPage":"1","endPage":"11","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":479950,"rank":0,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/96wr02586","text":"Publisher Index Page"},{"id":337813,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"33","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58ccf5a0e4b0849ce97f0d08","contributors":{"authors":[{"text":"Ezzedine, Souheil","contributorId":189491,"corporation":false,"usgs":false,"family":"Ezzedine","given":"Souheil","email":"","affiliations":[],"preferred":false,"id":684982,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rubin, Yoram","contributorId":189432,"corporation":false,"usgs":false,"family":"Rubin","given":"Yoram","email":"","affiliations":[],"preferred":false,"id":684983,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70019280,"text":"70019280 - 1997 - Energy sources and ecological role of crayfishes in an Ozark stream: Insights from stable isotopes and gut analysis","interactions":[],"lastModifiedDate":"2012-03-12T17:19:11","indexId":"70019280","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1169,"text":"Canadian Journal of Fisheries and Aquatic Sciences","active":true,"publicationSubtype":{"id":10}},"title":"Energy sources and ecological role of crayfishes in an Ozark stream: Insights from stable isotopes and gut analysis","docAbstract":"Energy sources for the crayfishes Orconectes luteus and O. punctimanus in the Jacks Fork River, Missouri, were quantified using stable isotopes (??13C and ??15N) and gut-content analysis. A dual-isotope mixing model indicated that about two thirds of crayfish production originated from allochthonous carbon sources, and 30-50% of crayfish production was derived from direct consumption of animal matter. Young-of-the-year crayfishes and adult O. luteus were more carnivorous than the larger adult O. punctimanus. Contributions of energy sources determined using the stable isotope mixing model were similar to results of gut-content analysis corrected for differential assimilation of dietary components. Proportions of crayfish production attributed to animal matter by these two methods were four to five times greater than estimates derived from uncorrected gut-content analysis. Unadjusted gut-content analysis overestimated the percentage of crayfish production from feeding directly on detritus. Production-based calculations of crayfish food consumption rates indicated that crayfishes were the dominant consumers of benthic invertebrates, detritus, and algae and may strongly influence lower trophic levels, organic matter processing, and energy flow in this system.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Canadian Journal of Fisheries and Aquatic Sciences","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1139/cjfas-54-11-2555","issn":"0706652X","usgsCitation":"Whitledge, G., and Rabeni, C., 1997, Energy sources and ecological role of crayfishes in an Ozark stream: Insights from stable isotopes and gut analysis: Canadian Journal of Fisheries and Aquatic Sciences, v. 54, no. 11, p. 2555-2563, https://doi.org/10.1139/cjfas-54-11-2555.","startPage":"2555","endPage":"2563","numberOfPages":"9","costCenters":[],"links":[{"id":205716,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1139/cjfas-54-11-2555"},{"id":226372,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"54","issue":"11","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a094fe4b0c8380cd51e79","contributors":{"authors":[{"text":"Whitledge, G.W.","contributorId":33465,"corporation":false,"usgs":true,"family":"Whitledge","given":"G.W.","email":"","affiliations":[],"preferred":false,"id":382220,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rabeni, C.F.","contributorId":67823,"corporation":false,"usgs":true,"family":"Rabeni","given":"C.F.","affiliations":[],"preferred":false,"id":382221,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70174704,"text":"70174704 - 1997 - Water quality variability in San Francisco Bay, Some gGeneral lessons from 1996 sampling: 1996 annual report, San Francisco estuary regional monitoring program for trace substances","interactions":[],"lastModifiedDate":"2016-07-26T16:44:43","indexId":"70174704","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":9,"text":"Other Report"},"title":"Water quality variability in San Francisco Bay, Some gGeneral lessons from 1996 sampling: 1996 annual report, San Francisco estuary regional monitoring program for trace substances","docAbstract":"This report describes the results from the 1996 Regional Monitoring Program for Trace Substances (RMP). It is the fourth Annual Report from the RMP which began in 1993 and attempts to synthesize the most obvious data patterns from the last four years. This report includes data from Base Program monitoring activities, as well as results of Pilot and Special Studies conducted or completed in 1996. Additionally, several articles contributed by RMP investigators and others, are included. These articles provide perspective and insight on important contaminant issues identified by the RMP. This summary addresses which kinds of pollutants measured by the RMP appear to be at levels that warrant concern, what kinds of trends may be discerned, and which stations have consistently shown elevated contaminant levels. The goals or general objectives of the RMP are: 1. To obtain high quality baseline data describing the concentrations of toxic and potentially toxic trace elements and organic contaminants in the water and sediment of the San Francisco Estuary. 2. To determine seasonal and annual trends in chemical and biological water quality in the San Francisco Estuary. 3. To continue to develop a data set that can be used to determine long-term trends in the concentrations of toxic and potentially toxic trace elements and organic contaminants in the water and sediments of the San Francisco Estuary. 4. To determine whether water quality and sediment quality in the Estuary at large are in compliance with objectives established by the Basin Plan (the regulatory planning document used by the Regional Water Quality Control Board). 5. To provide a database on water and sediment quality in the Estuary which is compatible with data being developed in other ongoing studies, including wasteload allocation studies and model development, sediment quality objectives development, in-bay studies of dredged material disposal, Interagency Ecological Program (IEP) water quality studies, primary productivity studies, local effects biomonitoring programs, and state and federal mussel watch programs.
","language":"English","publisher":"San Francisco Estuary Institute","usgsCitation":"Cloern, J., Cole, B., Edmunds, J., and Baylosis, J., 1997, Water quality variability in San Francisco Bay, Some gGeneral lessons from 1996 sampling: 1996 annual report, San Francisco estuary regional monitoring program for trace substances, 15 p.","productDescription":"15 p.","startPage":"46","endPage":"60","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":325264,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":325263,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://www.sfei.org/documents/1996-annual-report-san-francisco-estuary-regional-monitoring-program-trace-substances"}],"country":"United States","state":"California","otherGeospatial":"San Francisco Bay 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E.","contributorId":59453,"corporation":false,"usgs":true,"family":"Cloern","given":"J. 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In an attempt to capture the habitat needs of Great Plains fish communities we are looking beyond previous habitat modeling methods. Traditional habitat modeling approaches have relied on one-dimensional hydraulic models and lumped compositional habitat metrics to describe aquatic habitat. A broader range of habitat descriptors is available when both composition and configuration of habitats is considered. Habitat metrics that consider both composition and configuration can be adapted from terrestrial biology. These metrics are most conveniently accessed with spatially explicit descriptors of the physical variables driving habitat composition. Two-dimensional hydrodynamic models have advanced to the point that they may provide the spatially explicit description of physical parameters needed to address this problem. This paper reports progress to date on applying two-dimensional hydraulic and habitat models on the Yellowstone and Missouri Rivers and uses examples from the Yellowstone River to illustrate the configurational metrics as a new tool for assessing riverine habitats.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"North American Lake Management Society (NALMS) meeting 1997","largerWorkSubtype":{"id":12,"text":"Conference publication"},"conferenceTitle":"North American Lake Management Society (NALMS) Meeting","conferenceDate":"December 2-4, 1997","conferenceLocation":"Houston, TX","language":"English","publisher":"NALMS","publisherLocation":"Houston, TX","usgsCitation":"Waddle, T.J., Bovee, K., and Bowen, Z., 1997, Two-dimensional habitat modeling in the Yellowstone/Upper Missouri River system, in North American Lake Management Society (NALMS) meeting 1997, Houston, TX, December 2-4, 1997, 13 p.","productDescription":"13 p.","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":291,"text":"Fort Collins Science Center","active":true,"usgs":true}],"links":[{"id":325410,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":325409,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://www.nalms.org/home/conferences-and-events/past-nalms-symposia/annual-symposium.cmsx"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"578dfdbae4b0f1bea0e0f905","contributors":{"authors":[{"text":"Waddle, T. 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In addition, 5 independent methods were used to calculate the annual mean net ecosystem metabolism (NEM = production - respiration) for the integrated Bay. These methods, which employed biogeochemical models, nutrient mass-balances anti summation of individual organic carbon fluxes, yielded remarkably similar estimates, with a mean NEM of +50 g C m-2 yr-1 (?? SE = 751, which is approximately 8% of the estimated annual average gross primary production. These calculations suggest a strong cross-sectional pattern in NEM throughout the Bay, wherein net heterotrophic metabolism prevails in the pelagic zones of the main channel, while net autotrophy occurs in the littoral zones which flank the deeper central area. For computational purposes, the estuary was separated into 3 regions along the land-sea gradient: (1) the oligohaline Upper Bay (11% of total area); (2) the mesohaline Mid Bay (36% of area); and (3) the polyhaline Lower Bay (53% of area). A distinct regional trend in NEM was observed along this salinity gradient, with net here(atrophy (NEM = 87 g C m-2 yr-1) in the Upper Bay, balanced metabolism in the Mid Bay and net autotrophy (NEM = +92 g C m-2 yr-1) in the Lower Bay. As a consequence of overall net autotrophy, the ratio of dissolved inorganic nitrogen (DIN) to total organic nitrogen (TON) changed from DIN:TON = 5.1 for riverine inputs to DIN:TON = 0.04 for water exported to the ocean. A striking feature of this organic C mass-balance was the relative dominance of biologically mediated metabolic fluxes compared to physical transport fluxes. The overall ratio of physical TOC inputs (1) to biotic primary production (P) was 0.08 for the whole estuary, but varied dramatically from 2.3 in the Upper Bay to 0.03 in the Mid and Lower Bay regions. Similarly, ecosystem respiration was some 6-fold higher than the sum of all physical carbon sinks. This general negative correspondence between I:P ratio and NEM, which occurred among Bay regions, was also evident in data available for organic C fluxes in other coastal ecosystems. An inverse relationship between NEM and P, postulated in a previous study, did not apply to Chesapeake Bay, and closer examination of available data revealed the importance of the loading ratio of DIN:TOC as a key control on coastal NEM. It is proposed here that the general global trend of coastal eutrophication will lead to increasing values of NEM in estuaries worldwide. The management implications of this trend are complex, involving both increased potential fisheries harvest and decreased demersal habitat.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Ecology Progress Series","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Inter-Research","doi":"10.3354/meps150229","issn":"01718630","usgsCitation":"Kemp, W., Smith, E., Marvin-DiPasquale, M., and Boynton, W., 1997, Organic carbon balance and net ecosystem metabolism in Chesapeake Bay: Marine Ecology Progress Series, v. 150, no. 1-3, p. 229-248, https://doi.org/10.3354/meps150229.","startPage":"229","endPage":"248","numberOfPages":"20","costCenters":[],"links":[{"id":480037,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.3354/meps150229","text":"Publisher Index Page"},{"id":227742,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":266001,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.3354/meps150229"}],"volume":"150","issue":"1-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6f91e4b0c8380cd75b6c","contributors":{"authors":[{"text":"Kemp, W. M.","contributorId":77990,"corporation":false,"usgs":true,"family":"Kemp","given":"W. M.","affiliations":[],"preferred":false,"id":384672,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Smith, E.M.","contributorId":94450,"corporation":false,"usgs":true,"family":"Smith","given":"E.M.","email":"","affiliations":[],"preferred":false,"id":384673,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Marvin-DiPasquale, M.","contributorId":28367,"corporation":false,"usgs":true,"family":"Marvin-DiPasquale","given":"M.","affiliations":[],"preferred":false,"id":384670,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Boynton, W.R.","contributorId":77679,"corporation":false,"usgs":true,"family":"Boynton","given":"W.R.","email":"","affiliations":[],"preferred":false,"id":384671,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":1008600,"text":"1008600 - 1997 - A rop net and removable walkway used to quantitatively sample fishes over wetland surfaces in the dwarf mangrove of the Southern Everglades","interactions":[],"lastModifiedDate":"2016-01-06T11:23:52","indexId":"1008600","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3750,"text":"Wetlands","onlineIssn":"1943-6246","printIssn":"0277-5212","active":true,"publicationSubtype":{"id":10}},"title":"A rop net and removable walkway used to quantitatively sample fishes over wetland surfaces in the dwarf mangrove of the Southern Everglades","docAbstract":"We describe a 9 m2 drop net and removable walkways designed to quantify densities of small fishes in wetland habitats with low to moderate vegetation density. The method permits the collection of small, quantitative, discrete samples in ecologically sensitive areas by combining rapid net deployment from fixed sites with the carefully contained use of the fish toxicant rotenone. This method requires very little contact with the substrate, causes minimal alteration to the habitat being sampled, samples small fishes in an unbiased manner, and allows for differential sampling of microhabitats within a wetland. When used in dwarf red mangrove (Rhizophora mangle) habitat in southern Everglades National Park and adjacent areas (September 1990 to March 1993), we achieved high recovery efficiencies (78–90%) for five common species <110 mm in length. We captured 20,193 individuals of 26 species. The most abundant fishes were sheepshead minnowCyprinodon variegatus, goldspotted killifishFloridichthys carpio, rainwater killifishLucania parva, sailfin mollyPoecilia latipinna, and the exotic Mayan cichlidCichlasoma urophthalmus. The 9 m2 drop net and associated removable walkways are versatile and can be used in a variety of wetland types, including both interior and coastal wetlands with either herbaceous or woody vegetation.
","language":"English","publisher":"Springer","doi":"10.1007/BF03161424","usgsCitation":"Lorenz, J., McIvor, C., Powell, G., and Frederick, P.C., 1997, A rop net and removable walkway used to quantitatively sample fishes over wetland surfaces in the dwarf mangrove of the Southern Everglades: Wetlands, v. 17, p. 346-359, https://doi.org/10.1007/BF03161424.","productDescription":"14 p.","startPage":"346","endPage":"359","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":566,"text":"Southeast Ecological Science Center","active":true,"usgs":true}],"links":[{"id":132485,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"17","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a5ee4b07f02db633dad","contributors":{"authors":[{"text":"Lorenz, J.J.","contributorId":67058,"corporation":false,"usgs":true,"family":"Lorenz","given":"J.J.","email":"","affiliations":[],"preferred":false,"id":318188,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McIvor, C.C.","contributorId":38104,"corporation":false,"usgs":true,"family":"McIvor","given":"C.C.","email":"","affiliations":[],"preferred":false,"id":318186,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Powell, G.V.N.","contributorId":23894,"corporation":false,"usgs":true,"family":"Powell","given":"G.V.N.","email":"","affiliations":[],"preferred":false,"id":318185,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Frederick, P. C.","contributorId":66645,"corporation":false,"usgs":true,"family":"Frederick","given":"P.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":318187,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70019534,"text":"70019534 - 1997 - A three component model to estimate sensible heat flux over sparse shrubs in Nevada","interactions":[],"lastModifiedDate":"2025-07-17T15:59:36.635337","indexId":"70019534","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3252,"text":"Remote Sensing Reviews","active":true,"publicationSubtype":{"id":10}},"title":"A three component model to estimate sensible heat flux over sparse shrubs in Nevada","docAbstract":"It is now recognized that accurate partitioning of available energy into sensible and latent heat flux is crucial to understanding surface‐atmosphere interactions. This issue is more complicated in arid and semi‐arid regions where the relative contribution to surface fluxes from the soil and vegetation may vary significantly throughout the day and throughout the season. The objective of this paper is to present a three‐component model to estimate sensible heat flux over heterogeneous surfaces. The surface was represented with two adjacent compartments. The first compartment is made up of two components, shrubs and shaded soil; the second compartment consists of bare, unshaded soil. Data collected at two different sites in Nevada during the summers of 1991 and 1992 were used to evaluate model performance. The results show that the present model is sufficiently general to yield satisfactory results for both sites.
","language":"English","publisher":"Taylor & Francis","doi":"10.1080/02757259709532333","issn":"02757257","usgsCitation":"Chehbouni, A., Nichols, W.D., Njoku, E., Qi, J., Kerr, Y., and Cabot, F., 1997, A three component model to estimate sensible heat flux over sparse shrubs in Nevada: Remote Sensing Reviews, v. 15, no. 1-4, p. 99-112, https://doi.org/10.1080/02757259709532333.","productDescription":"14 p.","startPage":"99","endPage":"112","numberOfPages":"14","costCenters":[],"links":[{"id":228043,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"15","issue":"1-4","noUsgsAuthors":false,"publicationDate":"2009-10-19","publicationStatus":"PW","scienceBaseUri":"5059e310e4b0c8380cd45dd5","contributors":{"authors":[{"text":"Chehbouni, A.","contributorId":37095,"corporation":false,"usgs":true,"family":"Chehbouni","given":"A.","email":"","affiliations":[],"preferred":false,"id":383088,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Nichols, W. D.","contributorId":73220,"corporation":false,"usgs":true,"family":"Nichols","given":"W.","middleInitial":"D.","affiliations":[],"preferred":false,"id":383091,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Njoku, E.G.","contributorId":98057,"corporation":false,"usgs":true,"family":"Njoku","given":"E.G.","email":"","affiliations":[],"preferred":false,"id":383093,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Qi, J.","contributorId":48718,"corporation":false,"usgs":true,"family":"Qi","given":"J.","email":"","affiliations":[],"preferred":false,"id":383090,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Kerr, Y.H.","contributorId":38301,"corporation":false,"usgs":true,"family":"Kerr","given":"Y.H.","email":"","affiliations":[],"preferred":false,"id":383089,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Cabot, F.","contributorId":76478,"corporation":false,"usgs":true,"family":"Cabot","given":"F.","email":"","affiliations":[],"preferred":false,"id":383092,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70019522,"text":"70019522 - 1997 - Latitudinal distribution of O2on ganymede: Observations with the hubble space telescope","interactions":[],"lastModifiedDate":"2012-03-12T17:19:12","indexId":"70019522","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1963,"text":"Icarus","active":true,"publicationSubtype":{"id":10}},"title":"Latitudinal distribution of O2on ganymede: Observations with the hubble space telescope","docAbstract":"To help constrain the spatial variation of oxygen on Jupiter's satellite Ganymede, and hence have more clues to its mode of production and stability, we have obtained spectral data from the Faint Object Spectrograph (FOS) for a single pole-to-pole latitudinal strip, along with several Wide Field Planetary Camera 2 (WFPC2) images in three narrow band visible filters. All observations were made of the trailing hemisphere. In the FOS data we observe both visible absorptions at 0.577 and 0.627 ??m, associated with dense-phase oxygen (compressed gases, liquids, or solids). Filter options limited the WFPC2 observations to wavelengths near the weaker oxygen absorption at 0.627 ??m. These observations suggest that the dense-phase or dimer oxygen form is predominantly found in equatorial and mid-latitudes. The spectroscopic absorption feature appears in both bright and dark terrains but may be somewhat weaker in dark regions, which is consistent with the smaller mean photon path length in the surface in darker areas. Therefore, the abundance of oxygen appears more dependent on latitude and longitude constraints than surface albedo. At the highest latitudes, where the ratio spectra have a strong upturn toward the blue, the oxygen bands do not appear. This relation suggests that dimer oxygen and ozone (as seen by Galileo) have opposite trends with latitude. Possible causes include competition or variation in the preferred stable form, which depends on temperature, solar ultraviolet flux, and/or surface age; enhancement of O3at the poles due to plasma interactions; or viewing geometry effects that reduce the oxygen features at the poles when observed from Earth. The predominantly equatorial feature supports the production of O2through plasma bombardment and favors defect trapping over physical adsorption of the dimer molecules in the surface. We briefly consider the implications of Ganymede's magnetosphere for our understanding of O2and O3distribution on Ganymede. ?? 1997 Academic Press.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Icarus","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1006/icar.1997.5842","issn":"00191035","usgsCitation":"Calvin, W.M., and Spencer, J., 1997, Latitudinal distribution of O2on ganymede: Observations with the hubble space telescope: Icarus, v. 130, no. 2, p. 505-516, https://doi.org/10.1006/icar.1997.5842.","startPage":"505","endPage":"516","numberOfPages":"12","costCenters":[],"links":[{"id":205723,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1006/icar.1997.5842"},{"id":226429,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"130","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a4582e4b0c8380cd673a2","contributors":{"authors":[{"text":"Calvin, W. M.","contributorId":17379,"corporation":false,"usgs":false,"family":"Calvin","given":"W.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":383048,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Spencer, J.R.","contributorId":106270,"corporation":false,"usgs":true,"family":"Spencer","given":"J.R.","email":"","affiliations":[],"preferred":false,"id":383049,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70019516,"text":"70019516 - 1997 - Transform push, oblique subduction resistance, and intraplate stress of the Juan de Fuca plate","interactions":[],"lastModifiedDate":"2024-09-30T14:16:14.621958","indexId":"70019516","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Transform push, oblique subduction resistance, and intraplate stress of the Juan de Fuca plate","docAbstract":"The Juan de Fuca plate is a small oceanic plate between the Pacific and North America plates. In the southernmost region, referred to as the Gorda deformation zone, the maximum compressive stress σ1 constrained by earthquake focal mechanisms is N-S. Off Oregon, and possibly off Washington, NW trending left-lateral faults cutting the Juan de Fuca plate indicate a σ1 in a NE-SW to E-W direction. The magnitude of differential stress increases from north to south; this is inferred from the plastic yielding and distribution of earthquakes throughout the Gorda deformation zone. To understand how tectonic forces determine the stress field of the Juan de Fuca plate, we have modeled the intraplate stress using both elastic and elastic-perfectly plastic plane-stress finite element models. We conclude that the right-lateral shear motion of the Pacific and North America plates is primarily responsible for the stress pattern of the Juan de Fuca plate. The most important roles are played by a compressional force normal to the Mendocino transform fault, a result of the northward push by the Pacific plate and a horizontal resistance operating against the northward, or margin-parallel, component of oblique subduction. Margin-parallel subduction resistance results in large N-S compression in the Gorda deformation zone because the force is integrated over the full length of the Cascadia subduction zone. The Mendocino transform fault serves as a strong buttress that is very weak in shear but capable of transmitting large strike-normal compressive stresses. Internal failure of the Gorda deformation zone potentially places limits on the magnitude of the fault-normal stresses being transmitted and correspondingly on the magnitude of strike-parallel subduction resistance. Transform faults and oblique subduction zones in other parts of the world can be expected to transmit and create stresses in the same manner.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/96JB03114","issn":"01480227","usgsCitation":"Wang, K., He, J., and Davis, E., 1997, Transform push, oblique subduction resistance, and intraplate stress of the Juan de Fuca plate: Journal of Geophysical Research B: Solid Earth, v. 102, no. B1, p. 661-674, https://doi.org/10.1029/96JB03114.","productDescription":"14 p.","startPage":"661","endPage":"674","numberOfPages":"14","costCenters":[],"links":[{"id":480019,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/96jb03114","text":"Publisher Index Page"},{"id":226386,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"102","issue":"B1","noUsgsAuthors":false,"publicationDate":"1997-01-10","publicationStatus":"PW","scienceBaseUri":"505bb6d1e4b08c986b326ec3","contributors":{"authors":[{"text":"Wang, K.","contributorId":55975,"corporation":false,"usgs":true,"family":"Wang","given":"K.","affiliations":[],"preferred":false,"id":383031,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"He, J.","contributorId":95993,"corporation":false,"usgs":true,"family":"He","given":"J.","email":"","affiliations":[],"preferred":false,"id":383032,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Davis, E.E.","contributorId":105865,"corporation":false,"usgs":true,"family":"Davis","given":"E.E.","email":"","affiliations":[],"preferred":false,"id":383033,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70019514,"text":"70019514 - 1997 - The 1995 revision of the joint US/UK geomagnetic field models - I. Secular variation","interactions":[],"lastModifiedDate":"2012-03-12T17:19:13","indexId":"70019514","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1430,"text":"Earth, Planets and Space","active":true,"publicationSubtype":{"id":10}},"title":"The 1995 revision of the joint US/UK geomagnetic field models - I. Secular variation","docAbstract":"We present the methods used to derive mathematical models of global secular variation of the main geomagnetic field for the period 1985 to 2000. These secular-variation models are used in the construction of the candidate US/UK models for the Definitive Geomagnetic Reference Field at 1990, the International Geomagnetic Reference Field for 1995 to 2000, and the World Magnetic Model for 1995 to 2000 (see paper II, Quinn et al., 1997). The main sources of data for the secular-variation models are geomagnetic observatories and repeat stations. Over the areas devoid of these data secular-variation information is extracted from aeromagnetic and satellite data. We describe how secular variation is predicted up to the year 2000 at the observatories and repeat stations, how the aeromagnetic and satellite data are used, and how all the data are combined to produce the required models.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Earth, Planets and Space","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"13438832","usgsCitation":"Macmillan, S., Barraclough, D., Quinn, J., and Coleman, R., 1997, The 1995 revision of the joint US/UK geomagnetic field models - I. Secular variation: Earth, Planets and Space, v. 49, no. 2-3, p. 229-243.","startPage":"229","endPage":"243","numberOfPages":"15","costCenters":[],"links":[{"id":226384,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"49","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba637e4b08c986b320f88","contributors":{"authors":[{"text":"Macmillan, S.","contributorId":18522,"corporation":false,"usgs":true,"family":"Macmillan","given":"S.","email":"","affiliations":[],"preferred":false,"id":383019,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Barraclough, D.R.","contributorId":20735,"corporation":false,"usgs":true,"family":"Barraclough","given":"D.R.","email":"","affiliations":[],"preferred":false,"id":383020,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Quinn, J.M.","contributorId":48591,"corporation":false,"usgs":true,"family":"Quinn","given":"J.M.","email":"","affiliations":[],"preferred":false,"id":383021,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Coleman, R.J.","contributorId":59966,"corporation":false,"usgs":true,"family":"Coleman","given":"R.J.","email":"","affiliations":[],"preferred":false,"id":383022,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70019467,"text":"70019467 - 1997 - Altered streamflow and sediment entrainment in the Gunnison Gorge","interactions":[],"lastModifiedDate":"2024-05-29T23:18:49.886779","indexId":"70019467","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2529,"text":"Journal of the American Water Resources Association","active":true,"publicationSubtype":{"id":10}},"title":"Altered streamflow and sediment entrainment in the Gunnison Gorge","docAbstract":"The Gunnison River in the Gunnison Gorge is a canyon river where upstream dams regulate mainstem discharge but do not affect debris-flow sediment supply from tributaries entering below the reservoirs. Regulation since 1966 has altered flood frequency, streambed mobility, and fluvial geomorphology creating potential resource-management issues. The duration of moderate streamflows between 32.3 and 85.0 m3/s has increased threefold since 1966. This, along with flood-peak attenuation, has facilitated fine-sediment deposition and vegetation encroachment on stream banks. The Shields equation and on-site channel geometry and bed-material measurements were used to assess changes in sediment entrainment in four alluvial reaches. Sand and fine gravel are transported through riffle/pool reaches at most discharges, but the cobbles and boulders composing the streambed in many reaches now are infrequently entrained. Periodic debris flows add coarse sediment to rapids and can increase pool elevation and the streambed area affected by backwater and fine-sediment accumulation. Debris-flow supplied boulders accumulate on fans and in rapids and constrict the channel until reworked by larger floods. The response to streamflow-regime changes in the Gunnison Gorge could serve as an analog for alluvial reaches in other regulated canyon rivers.","language":"English","publisher":"American Water Resources Association","doi":"10.1111/j.1752-1688.1997.tb04123.x","issn":"1093474X","usgsCitation":"Elliott, J.G., and Parker, R.S., 1997, Altered streamflow and sediment entrainment in the Gunnison Gorge: Journal of the American Water Resources Association, v. 33, no. 5, p. 1041-1054, https://doi.org/10.1111/j.1752-1688.1997.tb04123.x.","productDescription":"14 p.","startPage":"1041","endPage":"1054","numberOfPages":"14","costCenters":[],"links":[{"id":226881,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"33","issue":"5","noUsgsAuthors":false,"publicationDate":"2007-06-08","publicationStatus":"PW","scienceBaseUri":"5059e97be4b0c8380cd482ef","contributors":{"authors":[{"text":"Elliott, J. G.","contributorId":45341,"corporation":false,"usgs":true,"family":"Elliott","given":"J.","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":382823,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Parker, R. S.","contributorId":104510,"corporation":false,"usgs":true,"family":"Parker","given":"R.","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":382824,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70019552,"text":"70019552 - 1997 - A mechanism for high wall-rock velocities in rockbursts","interactions":[],"lastModifiedDate":"2012-03-12T17:19:16","indexId":"70019552","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3208,"text":"Pure and Applied Geophysics","active":true,"publicationSubtype":{"id":10}},"title":"A mechanism for high wall-rock velocities in rockbursts","docAbstract":"Considerable evidence has been reported for wall-rock velocities during rockbursts in deep gold mines that are substantially greater than ground velocities associated with the primary seismic events. Whereas varied evidence suggests that slip across a fault at the source of an event generates nearby particle velocities of, at most, several m/s, numerous observations, in nearby damaged tunnels, for instance, imply wall-rock velocities of the order of 10 m/s and greater. The common observation of slab buckling or breakouts in the sidewalls of damaged excavations suggests that slab flexure may be the mechanism for causing high rock ejection velocities. Following its formation, a sidewall slab buckles, causing the flexure to increase until the stress generated by flexure reaches the limit 5 that can be supported by the sidewall rock. I assume here that S is the uniaxial compressive strength. Once the flexural stress exceeds S, presumably due to the additional load imposed by a nearby seismic event, the slab fractures and unflexes violently. The peak wall-rock velocity v thereby generated is given by v=(3 + 1-??2/2)1 2 S/?????E for rock of density ??, Young's modulus E, and Poisson's ratio ??. Typical values of these rock properties for the deep gold mines of South Africa yield v= 26 m/s and for especially strong quartzites encountered in these same mines, v> 50m/s. Even though this slab buckling process leads to remarkably high ejection velocities and violent damage in excavations, the energy released during this failure is only a tiny fraction of that released in the primary seismic event, typically of magnitude 2 or greater.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Pure and Applied Geophysics","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"00334553","usgsCitation":"McGarr, A., 1997, A mechanism for high wall-rock velocities in rockbursts: Pure and Applied Geophysics, v. 150, no. 3-4, p. 381-391.","startPage":"381","endPage":"391","numberOfPages":"11","costCenters":[],"links":[{"id":228316,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"150","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e44be4b0c8380cd46565","contributors":{"authors":[{"text":"McGarr, Art 0000-0001-9769-4093","orcid":"https://orcid.org/0000-0001-9769-4093","contributorId":43491,"corporation":false,"usgs":true,"family":"McGarr","given":"Art","affiliations":[],"preferred":false,"id":383149,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70019989,"text":"70019989 - 1997 - Potential effects of climate change on aquatic ecosystems of the Great Plains of North America","interactions":[],"lastModifiedDate":"2024-03-26T22:55:19.393475","indexId":"70019989","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1924,"text":"Hydrological Processes","active":true,"publicationSubtype":{"id":10}},"title":"Potential effects of climate change on aquatic ecosystems of the Great Plains of North America","docAbstract":"The Great Plains landscape is less topographically complex than most other regions within North America, but diverse aquatic ecosystems, such as playas, pothole lakes, ox-bow lakes, springs, groundwater aquifers, intermittent and ephemeral streams, as well as large rivers and wetlands, are highly dynamic and responsive to extreme climatic fluctuations. We review the evidence for climatic change that demonstrates the historical importance of extremes in north-south differences in summer temperatures and east-west differences in aridity across four large subregions. These physical driving forces alter density stratification, deoxygenation, decomposition and salinity. Biotic community composition and associated ecosystem processes of productivity and nutrient cycling respond rapidly to these climatically driven dynamics. Ecosystem processes also respond to cultural effects such as dams and diversions of water for irrigation, waste dilution and urban demands for drinking water and industrial uses. Distinguishing climatic from cultural effects in future models of aquatic ecosystem functioning will require more refinement in both climatic and economic forecasting. There is a need, for example, to predict how long-term climatic forecasts (based on both ENSO and global warming simulations) relate to the permanence and productivity of shallow water ecosystems. Aquatic ecologists, hydrologists, climatologists and geographers have much to discuss regarding the synthesis of available data and the design of future interdisciplinary research.
","language":"English","publisher":"Wiley","issn":"08856087","usgsCitation":"Covich, A., Fritz, S., Lamb, P., Marzolf, R., Matthews, W., Poiani, K., Prepas, E., Richman, M., and Winter, T.C., 1997, Potential effects of climate change on aquatic ecosystems of the Great Plains of North America: Hydrological Processes, v. 11, no. 8, p. 993-1021.","productDescription":"29 p.","startPage":"993","endPage":"1021","numberOfPages":"29","costCenters":[],"links":[{"id":228149,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"11","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7ecde4b0c8380cd7a767","contributors":{"authors":[{"text":"Covich, A.P.","contributorId":14965,"corporation":false,"usgs":true,"family":"Covich","given":"A.P.","email":"","affiliations":[],"preferred":false,"id":384614,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fritz, S.C.","contributorId":77892,"corporation":false,"usgs":true,"family":"Fritz","given":"S.C.","email":"","affiliations":[],"preferred":false,"id":384622,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lamb, P.J.","contributorId":19724,"corporation":false,"usgs":true,"family":"Lamb","given":"P.J.","email":"","affiliations":[],"preferred":false,"id":384615,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Marzolf, R.D.","contributorId":39538,"corporation":false,"usgs":true,"family":"Marzolf","given":"R.D.","email":"","affiliations":[],"preferred":false,"id":384618,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Matthews, W.J.","contributorId":70343,"corporation":false,"usgs":true,"family":"Matthews","given":"W.J.","email":"","affiliations":[],"preferred":false,"id":384621,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Poiani, K.A.","contributorId":52690,"corporation":false,"usgs":true,"family":"Poiani","given":"K.A.","affiliations":[],"preferred":false,"id":384619,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Prepas, E.E.","contributorId":57223,"corporation":false,"usgs":true,"family":"Prepas","given":"E.E.","email":"","affiliations":[],"preferred":false,"id":384620,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Richman, M.B.","contributorId":32315,"corporation":false,"usgs":true,"family":"Richman","given":"M.B.","email":"","affiliations":[],"preferred":false,"id":384617,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Winter, T. C.","contributorId":23485,"corporation":false,"usgs":true,"family":"Winter","given":"T.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":384616,"contributorType":{"id":1,"text":"Authors"},"rank":9}]}} ,{"id":70019472,"text":"70019472 - 1997 - Quantifying Anderson's fault types","interactions":[],"lastModifiedDate":"2024-07-19T15:47:15.352063","indexId":"70019472","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Quantifying Anderson's fault types","docAbstract":"Anderson [1905] explained three basic types of faulting (normal, strike-slip, and reverse) in terms of the shape of the causative stress tensor and its orientation relative to the Earth's surface. Quantitative parameters can be defined which contain information about both shape and orientation [Célérier, 1995], thereby offering a way to distinguish fault-type domains on plots of regional stress fields and to quantify, for example, the degree of normal-faulting tendencies within strike-slip domains. This paper offers a geometrically motivated generalization of Angelier's [1979, 1984, 1990] shape parameters ϕ and ψ to new quantities named Aϕ and Aψ. In their simple forms, Aϕ varies from 0 to 1 for normal, 1 to 2 for strike-slip, and 2 to 3 for reverse faulting, and Aψ/ranges from 0° to 60°, 60° to 120°, and 120° to 180°, respectively. After scaling, Aϕ and Aψ agree to within 2% (or 1°), a difference of little practical significance, although Aψ has smoother analytical properties. A formulation distinguishing horizontal axes as well as the vertical axis is also possible, yielding an Aϕ ranging from −3 to +3 and Aψ from −180° to +180°. The geometrically motivated derivation in three-dimensional stress space presented here may aid intuition and offers a natural link with traditional ways of plotting yield and failure criteria. Examples are given, based on models of Bird [1996] and Bird and Kong [1994], of the use of Anderson fault parameters Aϕ and Aψ for visualizing tectonic regimes defined by regional stress fields.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/97JB01274","issn":"01480227","usgsCitation":"Simpson, R., 1997, Quantifying Anderson's fault types: Journal of Geophysical Research B: Solid Earth, v. 102, no. B8, p. 17909-17919, https://doi.org/10.1029/97JB01274.","productDescription":"11 p.","startPage":"17909","endPage":"17919","numberOfPages":"11","costCenters":[],"links":[{"id":226884,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"102","issue":"B8","noUsgsAuthors":false,"publicationDate":"1997-08-10","publicationStatus":"PW","scienceBaseUri":"505a91bbe4b0c8380cd8041c","contributors":{"authors":[{"text":"Simpson, R.W.","contributorId":76738,"corporation":false,"usgs":true,"family":"Simpson","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":382858,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70019573,"text":"70019573 - 1997 - Geochronologic and paleomagnetic evidence defining the relationship between the Miocene Hiko and Racer Canyon tuffs, eccentric outflow lobes from the Caliente caldera complex, southeastern Great Basin, USA","interactions":[],"lastModifiedDate":"2023-11-08T01:26:41.198463","indexId":"70019573","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1109,"text":"Bulletin of Volcanology","active":true,"publicationSubtype":{"id":10}},"title":"Geochronologic and paleomagnetic evidence defining the relationship between the Miocene Hiko and Racer Canyon tuffs, eccentric outflow lobes from the Caliente caldera complex, southeastern Great Basin, USA","docAbstract":"Outflow sheets of the Hiko tuff and the Racer Canyon tuff, which together extend over approximately 16 000 km2 around the Caliente caldera complex in southeastern Nevada, have long been considered to be products of simultaneous or near-simultaneous eruptions from inset calderas in the west and east ends, respectively, of the caldera complex. New high-precision 40Ar/39Ar geochronology and paleomagnetic data demonstrate that emplacement of the uppermost part of the Racer Canyon tuff at 18.33±0.03 Ma was nearly synchronous with emplacement of the single outflow cooling unit of the much larger overlying Hiko tuff at 18.32±0.04 Ma. Based on comparison with the geomagnetic polarity time scale derived from the sea-floor spreading record, we conclude that emplacement of the first of several outflow cooling units of the Racer Canyon tuff commenced approximately 0.5 m.y. earlier. Only one paleomagnetic polarity is found in the Hiko tuff, but at least two paleomagnetic reversals have been found in the Racer Canyon tuff. The two formations overlap in only one place, at and near Panaca Summit northeast of the center of the Caliente caldera complex; here the Hiko tuff is stratigraphically above the Racer Canyon tuff. This study demonstrates the power of combining 40Ar/39Ar and paleomagnetic data in conjunction with phenocryst compositional modes to resolve problematic stratigraphic correlations in complex ash-flow sequences where use of one method alone might not eliminate ambiguities.
We explored the predictive value of common landscape characteristics for landslide vegetative stages in the Luquillo Experimental Forest of Puerto Rico using four different analyses. Maximum likelihood logistic regression showed that aspect, age, and substrate type could be used to predict vegetative structural stage. In addition it showed that the structural complexity of the vegetation was greater in landslides (1) facing the southeast (away from the dominant wind direction of recent hurricanes), (2) that were older, and (3) that had volcaniclastic rather than dioritic substrate. Multiple regression indicated that both elevation and age could be used to predict the current vegetation, and that vegetation complexity was greater both at lower elevation and in older landslides. Pearson product-moment correlation coefficients showed that (1) the presence of volcaniclastic substrate in landslides was negatively correlated with aspect, age, and elevation, (2) that road association and age were positively correlated, and (3) that slope was negatively correlated with area. Finally, principal components analysis showed that landslides were differentiated on axes defined primarily by age, aspect class, and elevation in the positive direction, and by volcaniclastic substrate in the negative direction. Because several statistical techniques indicated that age, aspect, elevation, and substrate were important in determining vegetation complexity on landslides, we conclude that landslide succession is influenced by variation in these landscape traits. In particular, we would expect to find more successional development on landslides which are older, face away from hurricane winds, are at lower elevation, and are on volcaniclastic substrate. Finally, our results lead into a hierarchical conceptual model of succession on landscapes where the biota respond first to either gradients or disturbance depending on their relative severity, and then to more local biotic mechanisms such as dispersal, predation and competition.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Landscape Ecology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Springer","doi":"10.1023/A:1007942804047","issn":"09212973","usgsCitation":"Myster, R., Thomlinson, J., and Larsen, M.C., 1997, Predicting landslide vegetation in patches on landscape gradients in Puerto Rico: Landscape Ecology, v. 12, no. 5, p. 299-307, https://doi.org/10.1023/A:1007942804047.","productDescription":"9 p.","startPage":"299","endPage":"307","numberOfPages":"9","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":156,"text":"Caribbean Water Science Center","active":true,"usgs":true}],"links":[{"id":226695,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"12","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a81b7e4b0c8380cd7b6bf","contributors":{"authors":[{"text":"Myster, R.W.","contributorId":49530,"corporation":false,"usgs":true,"family":"Myster","given":"R.W.","affiliations":[],"preferred":false,"id":382397,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Thomlinson, J.R.","contributorId":73757,"corporation":false,"usgs":true,"family":"Thomlinson","given":"J.R.","email":"","affiliations":[],"preferred":false,"id":382399,"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":382398,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":1008598,"text":"1008598 - 1997 - A simulation study of the spatiotemporal dynamics of the Unionid mussels","interactions":[],"lastModifiedDate":"2013-01-17T21:31:29","indexId":"1008598","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1458,"text":"Ecological Modelling","active":true,"publicationSubtype":{"id":10}},"title":"A simulation study of the spatiotemporal dynamics of the Unionid mussels","docAbstract":"Abstract not supplied at this time","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Ecological Modelling","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0304-3800(96)00039-7","usgsCitation":"Lee, H., and DeAngelis, D., 1997, A simulation study of the spatiotemporal dynamics of the Unionid mussels: Ecological Modelling, v. 95, p. 171-180, https://doi.org/10.1016/S0304-3800(96)00039-7.","productDescription":"p. 171-180","startPage":"171","endPage":"180","numberOfPages":"10","costCenters":[{"id":275,"text":"Florida Integrated Science Center","active":false,"usgs":true}],"links":[{"id":479964,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1016/s0304-3800(96)00039-7","text":"Publisher Index Page"},{"id":265841,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0304-3800(96)00039-7"},{"id":132742,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"95","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b17e4b07f02db6a6452","contributors":{"authors":[{"text":"Lee, Hooi-Ling","contributorId":16618,"corporation":false,"usgs":true,"family":"Lee","given":"Hooi-Ling","email":"","affiliations":[],"preferred":false,"id":318181,"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":318182,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70019574,"text":"70019574 - 1997 - Bactericidal activity of juvenile chinook salmon macrophages against Aeromonas salmonicida after exposure to live or heat-killed Renibacterium salmoninarum or to soluble proteins produced by R. salmoninarum","interactions":[],"lastModifiedDate":"2024-03-16T00:54:06.842109","indexId":"70019574","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2177,"text":"Journal of Aquatic Animal Health","active":true,"publicationSubtype":{"id":10}},"title":"Bactericidal activity of juvenile chinook salmon macrophages against Aeromonas salmonicida after exposure to live or heat-killed Renibacterium salmoninarum or to soluble proteins produced by R. salmoninarum","docAbstract":"Macrophages isolated from the anterior kidney of juvenile chinook salmon Oncorhynchus tshawytscha in 96-well microtiter plates were exposed for 72 h to 0, 105, or 106 live or heat-killed Renibacterium salmoninarum cells per well or to 0, 0.1, 1.0, or 10 μg/mL of R. salmoninarum soluble proteins. After treatment, the bactericidal activity of the macrophages against Aeromonas salmonicida was determined by a colorimetric assay based on the reduction of the tetrazolium dye MTT to formazan by viable bacteria. The MTT assay was modified to allow estimation of the percentage of bacteria killed by reference to a standard curve relating the number of bacteria added to microtiter wells to absorbance by formazan at 600 nm. The live and heatkilled R. salmoninarum treatments significantly (P < 0.001) increased killing of A. salmonicida by chinook salmon macrophages. In each of the five trials, significantly (P < 0.05) greater increases in killing occurred after exposure to 105 R. salmoninarum cells than to 106 R. salmoninarum cells per well. In contrast, treatment of macrophages with 10 ug/mL R. salmoninarum soluble proteins significantly (P < 0.001) decreased killing of A. salmonicida, but treatment with lower doses did not. These results show that the bactericidal activity of chinook salmon macrophages is stimulated by exposure to R. salmoninarum cells at lower dose levels but inhibited by exposure to R. salmoninarum cells or soluble proteins at higher dose levels.
Fault-zone guided waves were successfully excited by near-surface explosions in the San Andreas fault zone both at Parkfield and Cienega Valley, central California. The guided waves were observed on linear, three-component seismic arrays deployed across the fault trace. These waves were not excited by explosions located outside the fault zone. The amplitude spectra of guided waves show a maximum peak at 2 Hz at Parkfield and 3 Hz at Cienega Valley. The guided wave amplitude decays sharply with observation distance from the fault trace. The explosion-excited fault-zone guided waves are similar to those generated by earthquakes at Parkfield but have lower frequencies and travel more slowly. These observations suggest that the fault-zone wave guide has lower seismic velocities as it approaches the surface at Parkfield. We have modeled the waveforms as S waves trapped in a low-velocity wave guide sandwiched between high-velocity wall rocks, resulting in Love-type fault-zone guided waves. While the results are nonunique, the Parkfield data are adequately fit by a shallow wave guide 170 m wide with an S velocity 0.85 km/sec and an apparent Q ∼ 30 to 40. At Cienega Valley, the fault-zone wave guide appears to be about 120 m wide with an S velocity 0.7 km/sec and a Q ∼ 30.