{"pageNumber":"1278","pageRowStart":"31925","pageSize":"25","recordCount":40904,"records":[{"id":70019321,"text":"70019321 - 1997 - Supercritical fluid carbon dioxide extraction and liquid chromatographic separation with electrochemical detection of methylmercury from biological samples","interactions":[],"lastModifiedDate":"2024-02-14T14:37:37.284493","indexId":"70019321","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2040,"text":"International Journal of Environmental Analytical Chemistry","active":true,"publicationSubtype":{"id":10}},"title":"Supercritical fluid carbon dioxide extraction and liquid chromatographic separation with electrochemical detection of methylmercury from biological samples","docAbstract":"Using the coupled methods presented in this paper, methylmercury can be accurately and rapidly extracted from biological samples by modified supercritical fluid carbon dioxide and quantitated using liquid chromatography with reductive electrochemical detection. Supercritical fluid carbon dioxide modified with methanol effectively extracts underivatized methylmercury from certified reference materials Dorm-1 (dogfish muscle) and Dolt-2 (dogfish liver). Calcium chloride and water, with a ratio of 5:2 (by weight), provide the acid environment required for extracting methylmercury from sample matrices. Methylmercury chloride is separated from other organomercury chloride compounds using HPLC. The acidic eluent, containing 0.06 mol L-1 NaCl, insures the presence of methylmercury chloride and facilitates the reduction of mercury on a glassy carbon electrode. If dual glassy carbon electrodes are used, a positive peak is observed at -0.65 to -0.70 V and a negative peak is observed at -0.90V with the organomercury compounds that were tested. The practical detection limit for methylmercury is 5 X 10-8 mol L-1 (1 X 10-12 tool injected) when a 20 ??L injection loop is used.","language":"English","publisher":"Taylor & Francis","doi":"10.1080/03067319708030498","issn":"03067319","usgsCitation":"Simon, N., 1997, Supercritical fluid carbon dioxide extraction and liquid chromatographic separation with electrochemical detection of methylmercury from biological samples: International Journal of Environmental Analytical Chemistry, v. 68, no. 3, p. 313-330, https://doi.org/10.1080/03067319708030498.","productDescription":"18 p.","startPage":"313","endPage":"330","numberOfPages":"18","costCenters":[],"links":[{"id":226375,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"68","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9f55e4b08c986b31e4de","contributors":{"authors":[{"text":"Simon, N.S.","contributorId":103272,"corporation":false,"usgs":true,"family":"Simon","given":"N.S.","email":"","affiliations":[],"preferred":false,"id":382345,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70019316,"text":"70019316 - 1997 - Surfactant-enhanced remediation of a trichloroethene-contaminated aquifer. 1. Transport of triton X-100","interactions":[],"lastModifiedDate":"2012-03-12T17:19:30","indexId":"70019316","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Surfactant-enhanced remediation of a trichloroethene-contaminated aquifer. 1. Transport of triton X-100","docAbstract":"Transport of a nonionic surfactant (Triton X-100) at aqueous concentrations less than 400 mg/L through a trichloroethene-contaminated sand-and-gravel aquifer at Picatinny Arsenal, NJ, has been studied through a series of laboratory and field experiments. In the laboratory, batch and column experiments were conducted to quantify the rate and amount of Triton X-100 sorption to the aquifer sediments. In the field, a 400 mg/L aqueous Triton X-100 solution was injected into the aquifer at a rate of 26.5 L/min for a 35-d period. The transport of Triton X-100 was monitored by sampling and analysis of groundwater at six locations surrounding the injection well. Equilibrium batch sorption experiments showed that Triton X-100 sorbs strongly and nonlinearly to the field soil with the sharpest inflection point of the isotherm occurring at an equilibrium aqueous Triton X-100 concentration close to critical micelle concentration. Batch, soil column, and field experimental data were analyzed with zero-, one-, and two- dimensional (respectively) transient solute transport models with either equilibrium or rate-limited sorption. These analyses reveal that Triton X- 100 sorption to the aquifer solids is slow relative to advective and dispersive transport and that an equilibrium sorption model cannot simulate accurately the observed soil column and field data. Comparison of kinetic sorption parameters from batch, column, and field transport data indicate that both physical heterogeneities and Triton X-100 mass transfer between water and soil contribute to the kinetic transport effects.Transport of a nonionic surfactant (Triton X-100) at aqueous concentrations less than 400 mg/L through a trichloroethene-contaminated sand-and-gravel aquifer was studied. Equilibrium batch sorption experiments showed that Triton X-100 sorbs strongly and nonlinearly to the field soil with the sharpest inflection point of the isotherm occurring at an equilibrium aqueous Triton X-100 concentration close to critical micelle concentration. Batch, soil column, and field experimental data were analyzed with zero-, one-, and two-dimensional transient solute transport models with either equilibrium or rate-limited sorption. These analyses revealed that Triton X-100 sorption to the aquifer solids was slow relative to advective and dispersive transport.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Science and Technology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"ACS","publisherLocation":"Washington, DC, United States","doi":"10.1021/es970314v","issn":"0013936X","usgsCitation":"Smith, J.A., Sahoo, D., Mclellan, H., and Imbrigiotta, T., 1997, Surfactant-enhanced remediation of a trichloroethene-contaminated aquifer. 1. Transport of triton X-100: Environmental Science & Technology, v. 31, no. 12, p. 3565-3572, https://doi.org/10.1021/es970314v.","startPage":"3565","endPage":"3572","numberOfPages":"8","costCenters":[],"links":[{"id":205698,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es970314v"},{"id":226288,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"31","issue":"12","noUsgsAuthors":false,"publicationDate":"1997-11-26","publicationStatus":"PW","scienceBaseUri":"505ba1b7e4b08c986b31f27e","contributors":{"authors":[{"text":"Smith, J. A.","contributorId":101646,"corporation":false,"usgs":true,"family":"Smith","given":"J.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":382330,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sahoo, D.","contributorId":6601,"corporation":false,"usgs":true,"family":"Sahoo","given":"D.","email":"","affiliations":[],"preferred":false,"id":382328,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mclellan, H.M.","contributorId":104640,"corporation":false,"usgs":true,"family":"Mclellan","given":"H.M.","email":"","affiliations":[],"preferred":false,"id":382331,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Imbrigiotta, T.E. 0000-0003-1716-4768","orcid":"https://orcid.org/0000-0003-1716-4768","contributorId":86355,"corporation":false,"usgs":true,"family":"Imbrigiotta","given":"T.E.","affiliations":[],"preferred":false,"id":382329,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70019313,"text":"70019313 - 1997 - Subsidence of ash-flow calderas: Relation to caldera size and magma-chamber geometry","interactions":[],"lastModifiedDate":"2023-11-08T01:29:24.051936","indexId":"70019313","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":"Subsidence of ash-flow calderas: Relation to caldera size and magma-chamber geometry","docAbstract":"Diverse subsidence geometries and collapse processes for ash-flow calderas are inferred to reflect varying sizes, roof geometries, and depths of the source magma chambers, in combination with prior volcanic and regional tectonic influences. Based largely on a review of features at eroded pre-Quaternary calderas, a continuum of geometries and subsidence styles is inferred to exist, in both island-arc and continental settings, between small funnel calderas and larger plate (piston) subsidences bounded by arcuate faults. Within most ring-fault calderas, the subsided block is variably disrupted, due to differential movement during ash-flow eruptions and postcollapse magmatism, but highly chaotic piecemeal subsidence appears to be uncommon for large-diameter calderas. Small-scale downsag structures and accompanying extensional fractures develop along margins of most calderas during early stages of subsidence, but downsag is dominant only at calderas that have not subsided deeply. Calderas that are loci for multicyclic ash-flow eruption and subsidence cycles have the most complex internal structures. Large calderas have flared inner topographic walls due to landsliding of unstable slopes, and the resulting slide debris can constitute large proportions of caldera fill. Because the slide debris is concentrated near caldera walls, models from geophysical data can suggest a funnel geometry, even for large plate-subsidence calderas bounded by ring faults. Simple geometric models indicate that many large calderas have subsided 3-5 km, greater than the depth of most naturally exposed sections of intracaldera deposits. Many ring-fault platesubsidence calderas and intrusive ring complexes have been recognized in the western U.S., Japan, and elsewhere, but no well-documented examples of exposed eroded calderas have large-scale funnel geometry or chaotically disrupted caldera floors. Reported ignimbrite \"shields\" in the central Andes, where large-volume ash-flows are inferred to have erupted without caldera collapse, seem alternatively interpretable as more conventional calderas that were filled to overflow by younger lavas and tuffs. Some exposed subcaldera intrusions provide insights concerning subsidence processes, but such intrusions may continue to evolve in volume, roof geometry, depth, and composition after formation of associated calderas.","language":"English","publisher":"Springer","doi":"10.1007/s004450050186","issn":"02588900","usgsCitation":"Lipman, P.W., 1997, Subsidence of ash-flow calderas: Relation to caldera size and magma-chamber geometry: Bulletin of Volcanology, v. 59, no. 3, p. 198-218, https://doi.org/10.1007/s004450050186.","productDescription":"21 p.","startPage":"198","endPage":"218","numberOfPages":"21","costCenters":[],"links":[{"id":226919,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"59","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9d4fe4b08c986b31d787","contributors":{"authors":[{"text":"Lipman, P. W.","contributorId":93470,"corporation":false,"usgs":true,"family":"Lipman","given":"P.","middleInitial":"W.","affiliations":[],"preferred":false,"id":382319,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70021118,"text":"70021118 - 1997 - Viscoelastic coupling model of the San Andreas fault along the Big Bend, southern California","interactions":[],"lastModifiedDate":"2024-07-19T14:24:54.355213","indexId":"70021118","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":"Viscoelastic coupling model of the San Andreas fault along the Big Bend, southern California","docAbstract":"<p><span>The big bend segment of the San Andreas fault is the 300-km-long segment in southern California that strikes about N65°W, roughly 25° counterclockwise from the local tangent to the small circle about the Pacific-North America pole of rotation. The broad distribution of deformation of trilateration networks along this segment implies a locking depth of at least 25 km as interpreted by the conventional model of strain accumulation (continuous slip on the fault below the locking depth at the rate of relative plate motion), whereas the observed seismicity and laboratory data on fault strength suggest that the locking depth should be no greater than 10 to 15 km. The discrepancy is explained by the viscoelastic coupling model which accounts for the viscoelastic response of the lower crust. Thus the broad distribution of deformation observed across the big bend segment can be largely associated with the San Andreas fault itself, not subsidiary faults distributed throughout the region.&nbsp;</span><i>The Working Group on California Earthquake Probabilities</i><span>&nbsp;[1995] in using geodetic data to estimate the seismic risk in southern California has assumed that strain accumulated off the San Andreas fault is released by earthquakes located off the San Andreas fault. Thus they count the San Andreas contribution to total seismic moment accumulation more than once, leading to an overestimate of the seismicity for magnitude 6 and greater earthquakes in their Type C zones.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/98JB00148","issn":"01480227","usgsCitation":"Savage, J., and Lisowski, M., 1997, Viscoelastic coupling model of the San Andreas fault along the Big Bend, southern California: Journal of Geophysical Research B: Solid Earth, v. 103, no. 4, p. 7281-7292, https://doi.org/10.1029/98JB00148.","productDescription":"12 p.","startPage":"7281","endPage":"7292","numberOfPages":"12","costCenters":[],"links":[{"id":479982,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/98jb00148","text":"Publisher Index Page"},{"id":229658,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"103","issue":"4","noUsgsAuthors":false,"publicationDate":"1998-04-10","publicationStatus":"PW","scienceBaseUri":"505bc283e4b08c986b32abb3","contributors":{"authors":[{"text":"Savage, J.C. 0000-0002-5114-7673","orcid":"https://orcid.org/0000-0002-5114-7673","contributorId":102876,"corporation":false,"usgs":true,"family":"Savage","given":"J.C.","affiliations":[],"preferred":false,"id":388711,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lisowski, M.","contributorId":70381,"corporation":false,"usgs":true,"family":"Lisowski","given":"M.","email":"","affiliations":[],"preferred":false,"id":388710,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70019512,"text":"70019512 - 1997 - Crustal implications of bedrock geology along the Trans-Alaska Crustal Transect (TACT) in the Brooks Range, northern Alaska","interactions":[],"lastModifiedDate":"2024-07-19T14:45:49.183847","indexId":"70019512","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":"Crustal implications of bedrock geology along the Trans-Alaska Crustal Transect (TACT) in the Brooks Range, northern Alaska","docAbstract":"<p><span>Geologic mapping of the Trans-Alaska Crustal Transect (TACT) project along the Dalton Highway in northern Alaska indicates that the Endicott Mountains allochthon and the Hammond terrane compose a combined allochthon that was thrust northward at least 90 km in the Early Cretaceous. The basal thrust of the combined allochthon climbs up section in the hanging wall from a ductile shear zone in the south through lower Paleozoic rocks of the Hammond terrane and into Upper Devonian rocks of the Endicott Mountains allochthon at the Mount Doonerak antiform, culminating in Early Cretaceous shale in the northern foothills of the Brooks Range. Footwall rocks north of the Mount Doonerak antiform are everywhere parautochthonous Permian and Triassic shale of the North Slope terrane rather than Jurassic and Lower Cretaceous strata of the Colville Basin as shown in most other tectonic models of the central Brooks Range. Stratigraphic and structural relations suggest that this thrust was the basal detachment for Early Cretaceous deformation. Younger structures, such as the Tertiary Mount Doonerak antiform, deform the Early Cretaceous structures and are cored by thrusts that root at a depth of about 10 to 30 km along a deeper detachment than the Early Cretaceous detachment. The Brooks Range, therefore, exposes (1) an Early Cretaceous thin-skinned deformational belt developed during arc-continent collision and (2) a mainly Tertiary thick-skinned orogen that is probabty the northward continuation of the Rocky Mountains orogenic belt. A down-to-the-south zone of both ductile and brittle normal faulting along the southern margin of the Brooks Range probably formed in the mid-Cretaceous by extensional exhumation of the Early Cretaceous contractional deformation.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/96JB03733","issn":"01480227","usgsCitation":"Moore, T., Wallace, W.K., Mull, C.G., Adams, K., Plafker, G., and Nokleberg, W., 1997, Crustal implications of bedrock geology along the Trans-Alaska Crustal Transect (TACT) in the Brooks Range, northern Alaska: Journal of Geophysical Research B: Solid Earth, v. 102, no. B9, p. 20645-20684, https://doi.org/10.1029/96JB03733.","productDescription":"40 p.","startPage":"20645","endPage":"20684","numberOfPages":"40","costCenters":[],"links":[{"id":489043,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/96jb03733","text":"Publisher Index Page"},{"id":226382,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"102","issue":"B9","noUsgsAuthors":false,"publicationDate":"1997-09-10","publicationStatus":"PW","scienceBaseUri":"5059fcdfe4b0c8380cd4e49d","contributors":{"authors":[{"text":"Moore, Thomas E. 0000-0002-0878-0457","orcid":"https://orcid.org/0000-0002-0878-0457","contributorId":85592,"corporation":false,"usgs":true,"family":"Moore","given":"Thomas E.","affiliations":[],"preferred":false,"id":383016,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wallace, W. K.","contributorId":31781,"corporation":false,"usgs":true,"family":"Wallace","given":"W.","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":383012,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mull, C. G.","contributorId":40220,"corporation":false,"usgs":true,"family":"Mull","given":"C.","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":383014,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Adams, K.E.","contributorId":9410,"corporation":false,"usgs":true,"family":"Adams","given":"K.E.","email":"","affiliations":[],"preferred":false,"id":383011,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Plafker, George 0000-0003-3972-0390","orcid":"https://orcid.org/0000-0003-3972-0390","contributorId":36603,"corporation":false,"usgs":true,"family":"Plafker","given":"George","affiliations":[],"preferred":false,"id":383013,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Nokleberg, W. J. 0000-0002-1574-8869","orcid":"https://orcid.org/0000-0002-1574-8869","contributorId":68312,"corporation":false,"usgs":true,"family":"Nokleberg","given":"W. J.","affiliations":[],"preferred":false,"id":383015,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}}
,{"id":70019286,"text":"70019286 - 1997 - Crustal deformation at long Valley Caldera, eastern California, 1992-1996 inferred from satellite radar interferometry","interactions":[],"lastModifiedDate":"2024-02-10T14:22:05.991942","indexId":"70019286","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","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":"Crustal deformation at long Valley Caldera, eastern California, 1992-1996 inferred from satellite radar interferometry","docAbstract":"<div class=\"\"><div class=\"article-section__content en main\"><p>Satellite radar interferometric images of Long Valley caldera show a pattern of surface deformation that resembles that expected from analysis of an extensive suite of ground-based geodetic data. Images from 2 and 4 year intervals respectively, are consistent with uniform movement rates determined from leveling surveys. Synthetic interferograms generated from ellipsoidal-inclusion source models based on inversion of the ground-based data show generally good agreement with the observed images. Two interferograms show evidence for a magmatic source southwest of the caldera in a region not covered by ground measurements. Poorer image quality in the 4 year interferogram indicates that temporal decorrelation of surface radar reflectors is progressively degrading the fringe pattern in the Long Valley region.</p></div></div>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/97GL02597","issn":"00948276","usgsCitation":"Thatcher, W., and Massonnet, D., 1997, Crustal deformation at long Valley Caldera, eastern California, 1992-1996 inferred from satellite radar interferometry: Geophysical Research Letters, v. 24, no. 20, p. 2519-2522, https://doi.org/10.1029/97GL02597.","productDescription":"4 p.","startPage":"2519","endPage":"2522","numberOfPages":"4","costCenters":[],"links":[{"id":479960,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/97gl02597","text":"Publisher Index Page"},{"id":226464,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"24","issue":"20","noUsgsAuthors":false,"publicationDate":"1997-10-15","publicationStatus":"PW","scienceBaseUri":"5059fcdbe4b0c8380cd4e487","contributors":{"authors":[{"text":"Thatcher, W.","contributorId":32669,"corporation":false,"usgs":true,"family":"Thatcher","given":"W.","email":"","affiliations":[],"preferred":false,"id":382238,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Massonnet, D.","contributorId":106272,"corporation":false,"usgs":true,"family":"Massonnet","given":"D.","email":"","affiliations":[],"preferred":false,"id":382239,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70019468,"text":"70019468 - 1997 - Calibration or verification? A balanced approach for science.","interactions":[],"lastModifiedDate":"2012-03-12T17:19:11","indexId":"70019468","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3212,"text":"Quality assurance (San Diego, Calif.)","active":true,"publicationSubtype":{"id":10}},"title":"Calibration or verification? A balanced approach for science.","docAbstract":"The calibration of balances is routinely performed both in the laboratory and the field. This process is required to accurately determine the weight of an object or chemical. The frequency of calibration and verification of balances is mandated by their use and location. Tolerance limits for balances could not be located in any standard procedure manuals. A survey was conducted to address the issues of calibration and verification frequency and to discuss the significance of defining tolerance limits for balances. Finally, for the benefit of laboratories unfamiliar with such procedures, we provide a working model based on our laboratory, the Upper Mississippi Science Center (UMSC), in La Crosse, Wisconsin.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Quality assurance (San Diego, Calif.)","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"10529411","usgsCitation":"Myers, C., and Kennedy, D., 1997, Calibration or verification? A balanced approach for science.: Quality assurance (San Diego, Calif.), v. 5, no. 4, p. 293-301.","startPage":"293","endPage":"301","numberOfPages":"9","costCenters":[],"links":[{"id":226882,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"5","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f319e4b0c8380cd4b5d8","contributors":{"authors":[{"text":"Myers, C.T.","contributorId":6201,"corporation":false,"usgs":true,"family":"Myers","given":"C.T.","email":"","affiliations":[],"preferred":false,"id":382825,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kennedy, D.M.","contributorId":49531,"corporation":false,"usgs":true,"family":"Kennedy","given":"D.M.","email":"","affiliations":[],"preferred":false,"id":382826,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70019638,"text":"70019638 - 1997 - Watershed responses to climate change at Glacier National Park","interactions":[],"lastModifiedDate":"2024-05-29T23:18:12.16166","indexId":"70019638","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":"Watershed responses to climate change at Glacier National Park","docAbstract":"<p>We have developed an approach which examines ecosystem function and the potential effects of climatic shifts. The Lake McDonald watershed of Glacier National Park was the focus for two linked research activities: acquisition of baseline data on hydrologic, chemical and aquatic organism attributes that characterize this pristine northern rocky mountain watershed, and further developing the Regional Hydro-Ecosystem Simulation System (RHESSys), a collection of integrated models which collectively provide spatially explicit, mechanistically-derived outputs of ecosystem processes, including hydrologic outflow, soil moisture, and snowpack water equivalence. In this unique setting field validation of RHESSys, outputs demonstrated that reasonable estimates of SWE and streamflow are being produced. RHESSys was used to predict annual stream discharge and temperature. The predictions, in conjunction with the field data, indicated that aquatic resources of the park may be significantly affected. Utilizing RHESSys to predict potential climate scenarios and response of other key ecosystem components can provide scientific insights as well as proactive guidelines for national park management.</p>","language":"English","publisher":"American Water Resources Association","doi":"10.1111/j.1752-1688.1997.tb04103.x","issn":"1093474X","usgsCitation":"Fagre, D., Comanor, P., White, J., Hauer, F.R., and Running, S.W., 1997, Watershed responses to climate change at Glacier National Park: Journal of the American Water Resources Association, v. 33, no. 4, p. 755-765, https://doi.org/10.1111/j.1752-1688.1997.tb04103.x.","productDescription":"11 p.","startPage":"755","endPage":"765","numberOfPages":"11","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":227677,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"33","issue":"4","noUsgsAuthors":false,"publicationDate":"2007-06-08","publicationStatus":"PW","scienceBaseUri":"505bcf79e4b08c986b32e902","contributors":{"authors":[{"text":"Fagre, D.B.","contributorId":52135,"corporation":false,"usgs":true,"family":"Fagre","given":"D.B.","email":"","affiliations":[],"preferred":false,"id":383397,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Comanor, P.L.","contributorId":47103,"corporation":false,"usgs":true,"family":"Comanor","given":"P.L.","email":"","affiliations":[],"preferred":false,"id":383395,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"White, J.D.","contributorId":42923,"corporation":false,"usgs":true,"family":"White","given":"J.D.","email":"","affiliations":[],"preferred":false,"id":383394,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hauer, F. Richard","contributorId":76892,"corporation":false,"usgs":true,"family":"Hauer","given":"F.","email":"","middleInitial":"Richard","affiliations":[],"preferred":false,"id":383398,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Running, S. W.","contributorId":51257,"corporation":false,"usgs":false,"family":"Running","given":"S.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":383396,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}}
,{"id":70019732,"text":"70019732 - 1997 - Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution","interactions":[],"lastModifiedDate":"2019-02-13T05:48:05","indexId":"70019732","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":"Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution","docAbstract":"<p><span>Fluid saturation, particle-size distribution, and porosity measurements were obtained from 269 core samples collected from six boreholes along a 90-m transect at a subregion of a crude-oil spill site, the north pool, near Bemidji, Minnesota. The oil saturation data, collected 11 years after the spill, showed an irregularly shaped oil body that appeared to be affected by sediment spatial variability. The particle-size distribution data were used to estimate the permeability (</span><i>k</i><span>) and retention curves for each sample. An additional 344<span>&nbsp;</span></span><i>k</i><span><span>&nbsp;</span>estimates were obtained from samples previously collected at the north pool. The 613<span>&nbsp;</span></span><i>k</i><span><span>&nbsp;</span>estimates were distributed bimodal lognormally with the two population distributions corresponding to the two predominant lithologies: a coarse glacial outwash deposit and fine-grained interbedded lenses. A two-step geostatistical approach was used to generate a conditioned realization of<span>&nbsp;</span></span><i>k</i><span><span>&nbsp;</span>representing the bimodal heterogeneity. A cross-sectional multiphase flow model was used to simulate the flow of oil and water in the presence of air along the north pool transect for an 11-year period. The inclusion of a representation of the bimodal aquifer heterogeneity was crucial for reproduction of general features of the observed oil body. If the bimodal heterogeneity was characterized, hysteresis did not have to be incorporated into the model because a hysteretic effect was produced by the sediment spatial variability. By revising the relative permeability functional relation, an improved reproduction of the observed oil saturation distribution was achieved. The inclusion of water table fluctuations in the model did not significantly affect the simulated oil saturation distribution.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/97WR00857","usgsCitation":"Dillard, L.A., Essaid, H.I., and Herkelrath, W.N., 1997, Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution: Water Resources Research, v. 33, no. 7, p. 1617-1632, https://doi.org/10.1029/97WR00857.","productDescription":"16 p.","startPage":"1617","endPage":"1632","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":480116,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/97wr00857","text":"Publisher Index Page"},{"id":227843,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"33","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6057e4b0c8380cd713b3","contributors":{"authors":[{"text":"Dillard, Leslie A.","contributorId":189405,"corporation":false,"usgs":false,"family":"Dillard","given":"Leslie","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":383736,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Essaid, Hedeff I. 0000-0003-0154-8628 hiessaid@usgs.gov","orcid":"https://orcid.org/0000-0003-0154-8628","contributorId":2284,"corporation":false,"usgs":true,"family":"Essaid","given":"Hedeff","email":"hiessaid@usgs.gov","middleInitial":"I.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":383735,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Herkelrath, William N. 0000-0002-6149-5524 wnherkel@usgs.gov","orcid":"https://orcid.org/0000-0002-6149-5524","contributorId":2612,"corporation":false,"usgs":true,"family":"Herkelrath","given":"William","email":"wnherkel@usgs.gov","middleInitial":"N.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":383737,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70020086,"text":"70020086 - 1997 - Dynamics of water-table fluctuations in an upland between two prairie-pothole wetlands in North Dakota","interactions":[],"lastModifiedDate":"2018-03-21T14:31:41","indexId":"70020086","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Dynamics of water-table fluctuations in an upland between two prairie-pothole wetlands in North Dakota","docAbstract":"<p><span>Data from a string of instrumented wells located on an upland of 55 m width between two wetlands in central North Dakota, USA, indicated frequent changes in water-table configuration following wet and dry periods during 5 years of investigation. A seasonal wetland is situated about 1.5 m higher than a nearby semipermanent wetland, suggesting an average ground water-table gradient of 0.02. However, water had the potential to flow as ground water from the upper to the lower wetland during only a few instances. A water-table trough adjacent to the lower semipermanent wetland was the most common water-table configuration during the first 4 years of the study, but it is likely that severe drought during those years contributed to the longevity and extent of the water-table trough. Water-table mounds that formed in response to rainfall events caused reversals of direction of flow that frequently modified the more dominant water-table trough during the severe drought. Rapid and large water-table rise to near land surface in response to intense rainfall was aided by the thick capillary fringe. One of the wettest summers on record ended the severe drought during the last year of the study, and caused a larger-scale water-table mound to form between the two wetlands. The mound was short in duration because it was overwhelmed by rising stage of the higher seasonal wetland which spilled into the lower wetland. Evapotranspiration was responsible for generating the water-table trough that formed between the two wetlands. Estimation of evapotranspiration based on diurnal fluctuations in wells yielded rates that averaged 3–5 mm day</span><sup>−1</sup><span>. On many occasions water levels in wells closer to the semipermanent wetland indicated a direction of flow that was different from the direction indicated by water levels in wells farther from the wetland. Misinterpretation of direction and magnitude of gradients between ground water and wetlands could result from poorly placed or too few observation wells, and also from infrequent measurement of water levels in wells.</span></p>","language":"English","publisher":"Elsevier","doi":"10.1016/S0022-1694(96)03050-8","issn":"00221694","usgsCitation":"Rosenberry, D.O., and Winter, T.C., 1997, Dynamics of water-table fluctuations in an upland between two prairie-pothole wetlands in North Dakota: Journal of Hydrology, v. 191, no. 1-4, p. 266-289, https://doi.org/10.1016/S0022-1694(96)03050-8.","productDescription":"24 p.","startPage":"266","endPage":"289","numberOfPages":"24","costCenters":[{"id":478,"text":"North Dakota Water Science Center","active":true,"usgs":true},{"id":34685,"text":"Dakota Water Science Center","active":true,"usgs":true}],"links":[{"id":227786,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205992,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0022-1694(96)03050-8"}],"volume":"191","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a043be4b0c8380cd5087a","contributors":{"authors":[{"text":"Rosenberry, Donald O. 0000-0003-0681-5641 rosenber@usgs.gov","orcid":"https://orcid.org/0000-0003-0681-5641","contributorId":1312,"corporation":false,"usgs":true,"family":"Rosenberry","given":"Donald","email":"rosenber@usgs.gov","middleInitial":"O.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true},{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":384972,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Winter, Thomas C.","contributorId":84736,"corporation":false,"usgs":true,"family":"Winter","given":"Thomas","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":384971,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70020022,"text":"70020022 - 1997 - Patterns and age distribution of ground-water flow to streams","interactions":[],"lastModifiedDate":"2024-03-08T01:06:16.868416","indexId":"70020022","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3825,"text":"Groundwater","active":true,"publicationSubtype":{"id":10}},"title":"Patterns and age distribution of ground-water flow to streams","docAbstract":"<p>Simulations of ground-water flow in a generic aquifer system were made to characterize the topology of ground-water flow in the stream subsystem and to evaluate its relation to deeper ground-water flow. The flow models are patterned after hydraulic characteristics of aquifers of the Atlantic Coastal Plain and are based on numerical solutions to three-dimensional, steady-state, unconfined flow. The models were used to evaluate the effects of aquifer horizontal-to-vertical hydraulic conductivity ratios, aquifer thickness, and areal recharge rates on flow in the stream subsystem. A particle tracker was used to determine flow paths in a stream subsystem, to establish the relation between ground-water seepage to points along a simulated stream and its source area of flow, and to determine ground-water residence time in stream subsystems. In a geometrically simple aquifer system with accretion, the source area of flow to streams resembles an elongated ellipse that tapers in the down gradient direction. Increased recharge causes an expansion of the stream subsystem. The source area of flow to the stream expands predominantly toward the stream headwaters. Base flow gain is also increased along the reach of the stream. A thin aquifer restricts ground-water flow and causes the source area of flow to expand near stream headwaters and also shifts the start-of-flow to the drainage basin divide. Increased aquifer anisotropy causes a lateral expansion of the source area of flow to streams.</p>","language":"English","publisher":"National Groundwater Association","doi":"10.1111/j.1745-6584.1997.tb00113.x","issn":"0017467X","usgsCitation":"Modica, E., Reilly, T.E., and Pollock, D., 1997, Patterns and age distribution of ground-water flow to streams: Groundwater, v. 35, no. 3, p. 523-537, https://doi.org/10.1111/j.1745-6584.1997.tb00113.x.","productDescription":"15 p.","startPage":"523","endPage":"537","numberOfPages":"15","costCenters":[],"links":[{"id":228071,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"35","issue":"3","noUsgsAuthors":false,"publicationDate":"2005-08-04","publicationStatus":"PW","scienceBaseUri":"505a75b6e4b0c8380cd77ccd","contributors":{"authors":[{"text":"Modica, E.","contributorId":69735,"corporation":false,"usgs":true,"family":"Modica","given":"E.","affiliations":[],"preferred":false,"id":384735,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reilly, T. E.","contributorId":79460,"corporation":false,"usgs":true,"family":"Reilly","given":"T.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":384736,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Pollock, D.W.","contributorId":30967,"corporation":false,"usgs":true,"family":"Pollock","given":"D.W.","email":"","affiliations":[],"preferred":false,"id":384734,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70019743,"text":"70019743 - 1997 - Persistence rates and detection probabilities of oiled king eider carcasses on St Paul Island, Alaska","interactions":[],"lastModifiedDate":"2018-05-13T12:40:00","indexId":"70019743","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2676,"text":"Marine Pollution Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Persistence rates and detection probabilities of oiled king eider carcasses on St Paul Island, Alaska","docAbstract":"Following an oil spill off St Paul Island, Alaska in February 1996, persistence rates and detection probabilities of oiled king eider (Somateria spectabilis) carcasses were estimated using the Cormack-Jolly-Seber model. Carcass persistence rates varied by day, beach type and sex, while detection probabilities varied by day and beach type. Scavenging, wave action and weather influenced carcass persistence. The patterns of persistence differed on rock and sand beaches and female carcasses had a different persistence function than males. Weather, primarily snow storms, and degree of carcass scavenging, diminished carcass detectability. Detection probabilities on rock beaches were lower and more variable than on sand beaches. The combination of persistence rates and detection probabilities can be used to improve techniques of estimating total mortality.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Pollution Bulletin","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0025-326X(96)00153-1","issn":"0025326X","usgsCitation":"Fowler, A.C., and Flint, P.L., 1997, Persistence rates and detection probabilities of oiled king eider carcasses on St Paul Island, Alaska: Marine Pollution Bulletin, v. 34, no. 7, p. 522-526, https://doi.org/10.1016/S0025-326X(96)00153-1.","startPage":"522","endPage":"526","numberOfPages":"5","costCenters":[],"links":[{"id":228057,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206047,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0025-326X(96)00153-1"}],"volume":"34","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a76f2e4b0c8380cd783aa","contributors":{"authors":[{"text":"Fowler, A. C.","contributorId":95836,"corporation":false,"usgs":true,"family":"Fowler","given":"A.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":383764,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Flint, Paul L. 0000-0002-8758-6993 pflint@usgs.gov","orcid":"https://orcid.org/0000-0002-8758-6993","contributorId":3284,"corporation":false,"usgs":true,"family":"Flint","given":"Paul","email":"pflint@usgs.gov","middleInitial":"L.","affiliations":[{"id":117,"text":"Alaska Science Center Biology WTEB","active":true,"usgs":true},{"id":114,"text":"Alaska Science Center","active":true,"usgs":true}],"preferred":true,"id":383763,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70019730,"text":"70019730 - 1997 - Evaluation of unconfined-aquifer parameters from pumping test data by nonlinear least squares","interactions":[],"lastModifiedDate":"2019-02-13T06:15:40","indexId":"70019730","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Evaluation of unconfined-aquifer parameters from pumping test data by nonlinear least squares","docAbstract":"Nonlinear least squares (NLS) with automatic differentiation was used to estimate aquifer parameters from drawdown data obtained from published pumping tests conducted in homogeneous, water-table aquifers. The method is based on a technique that seeks to minimize the squares of residuals between observed and calculated drawdown subject to bounds that are placed on the parameter of interest. The analytical model developed by Neuman for flow to a partially penetrating well of infinitesimal diameter situated in an infinite, homogeneous and anisotropic aquifer was used to obtain calculated drawdown. NLS was first applied to synthetic drawdown data from a hypothetical but realistic aquifer to demonstrate that the relevant hydraulic parameters (storativity, specific yield, and horizontal and vertical hydraulic conductivity) can be evaluated accurately. Next the method was used to estimate the parameters at three field sites with widely varying hydraulic properties. NLS produced unbiased estimates of the aquifer parameters that are close to the estimates obtained with the same data using a visual curve-matching approach. Small differences in the estimates are a consequence of subjective interpretation introduced in the visual approach.","language":"English","publisher":"Elsevier","doi":"10.1016/S0022-1694(96)03101-0","issn":"00221694","usgsCitation":"Heidari, M., and Moench, A., 1997, Evaluation of unconfined-aquifer parameters from pumping test data by nonlinear least squares: Journal of Hydrology, v. 192, no. 1-4, p. 300-313, https://doi.org/10.1016/S0022-1694(96)03101-0.","productDescription":"14 p.","startPage":"300","endPage":"313","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":227805,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205998,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0022-1694(96)03101-0"}],"volume":"192","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0d02e4b0c8380cd52dac","contributors":{"authors":[{"text":"Heidari, M.","contributorId":26430,"corporation":false,"usgs":true,"family":"Heidari","given":"M.","email":"","affiliations":[],"preferred":false,"id":383731,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Moench, A.","contributorId":12638,"corporation":false,"usgs":true,"family":"Moench","given":"A.","email":"","affiliations":[],"preferred":false,"id":383730,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70019746,"text":"70019746 - 1997 - Stratigraphic evolution of the inner continental shelf in response to late Quaternary relative sea-level change, northwestern Gulf of Maine","interactions":[],"lastModifiedDate":"2023-12-21T23:54:47.48568","indexId":"70019746","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Stratigraphic evolution of the inner continental shelf in response to late Quaternary relative sea-level change, northwestern Gulf of Maine","docAbstract":"<p>Accumulations of deltaic and littoral sediments on the inner continental shelf of Maine, Gulf of Maine, preserve a record of postglacial sea-level changes and shoreline migrations. The depositional response of coastal environments to a cycle of regression, lowstand, and transgression was examined with seismic-reflection profiles, vibracores, and radiocarbon dates collected from sediments at the mouths of the Kennebec and Penobscot Rivers. Sequence-stratigraphic analysis of these data reveals two distinctly different successions of late Quaternary deposits that represent end members in an evolutionary model for this glaciated coast. Seaward of the Kennebec River, coarse-grained shorelines with foreset beds occur at depths of 20–60 m and outline the lobate margin of the Kennebec River paleodelta, a complex, rock-framed accumulation of glaciomarine and deltaic sediments capped by estuarine and marine deposits. Sand derived from this system today supports large barrier spits and extensive salt marshes. In contrast, the mouth of the Penobscot River is characterized by thick deposits of glaciomarine mud overlain by marine mud of Holocene age, including gas-charged zones that have locally evolved into fields of pockmarks. The distinct lack of sand and gravel seaward of the Penobscot River and its abundance seaward of the Kennebec River probably reflect differences in sediment sources and the physiography of the two watersheds. The contrasting stratigraphic framework of these systems demonstrates the importance of understanding local and regional differences in sediment supply, sea-level change, bedrock structure, and exposure to waves and tides in order to model river-mouth deposition on glaciated coasts.</p>","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1997)109<0612:SEOTIC>2.3.CO;2","issn":"00167606","usgsCitation":"Barnhardt, W., Belknap, D.F., and Kelley, J.T., 1997, Stratigraphic evolution of the inner continental shelf in response to late Quaternary relative sea-level change, northwestern Gulf of Maine: Geological Society of America Bulletin, v. 109, no. 5, p. 612-630, https://doi.org/10.1130/0016-7606(1997)109<0612:SEOTIC>2.3.CO;2.","productDescription":"19 p.","startPage":"612","endPage":"630","numberOfPages":"19","costCenters":[],"links":[{"id":228133,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"Gulf of Maine","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"coordinates\": [\n          [\n            [\n              -70.33457912377591,\n              43.624017788854076\n            ],\n            [\n              -67.54405178002604,\n              43.624017788854076\n            ],\n            [\n              -67.54405178002604,\n              45.147053099936215\n            ],\n            [\n              -70.33457912377591,\n              45.147053099936215\n            ],\n            [\n              -70.33457912377591,\n              43.624017788854076\n            ]\n          ]\n        ],\n        \"type\": \"Polygon\"\n      }\n    }\n  ]\n}","volume":"109","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b98f7e4b08c986b31c1a7","contributors":{"authors":[{"text":"Barnhardt, W. A.","contributorId":86449,"corporation":false,"usgs":true,"family":"Barnhardt","given":"W. A.","affiliations":[],"preferred":false,"id":383771,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Belknap, D. F.","contributorId":96739,"corporation":false,"usgs":true,"family":"Belknap","given":"D.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":383772,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kelley, J. T.","contributorId":34197,"corporation":false,"usgs":true,"family":"Kelley","given":"J.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":383770,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70019469,"text":"70019469 - 1997 - Evaluation of process errors in bed load sampling using a Dune Model","interactions":[],"lastModifiedDate":"2018-03-15T10:33:36","indexId":"70019469","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":"Evaluation of process errors in bed load sampling using a Dune Model","docAbstract":"<p><span>Reliable estimates of the streamwide bed load discharge obtained using sampling devices are dependent upon good at-a-point knowledge across the full width of the channel. Using field data and information derived from a model that describes the geometric features of a dune train in terms of a spatial process observed at a fixed point in time, we show that sampling errors decrease as the number of samples collected increases, and the number of traverses of the channel over which the samples are collected increases. It also is preferable that bed load sampling be conducted at a pace which allows a number of bed forms to pass through the sampling cross section. The situations we analyze and simulate pertain to moderate transport conditions in small rivers. In such circumstances, bed load sampling schemes typically should involve four or five traverses of a river, and the collection of 20–40 samples at a rate of five or six samples per hour. By ensuring that spatial and temporal variability in the transport process is accounted for, such a sampling design reduces both random and systematic errors and hence minimizes the total error involved in the sampling process.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/97WR01711","usgsCitation":"Gomez, B., and Troutman, B.M., 1997, Evaluation of process errors in bed load sampling using a Dune Model: Water Resources Research, v. 33, no. 10, p. 2387-2398, https://doi.org/10.1029/97WR01711.","productDescription":"12 p.","startPage":"2387","endPage":"2398","costCenters":[],"links":[{"id":479988,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/97wr01711","text":"Publisher Index Page"},{"id":226843,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"33","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0cb0e4b0c8380cd52c64","contributors":{"authors":[{"text":"Gomez, Basil","contributorId":65475,"corporation":false,"usgs":true,"family":"Gomez","given":"Basil","email":"","affiliations":[],"preferred":false,"id":382827,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Troutman, Brent M.","contributorId":195329,"corporation":false,"usgs":false,"family":"Troutman","given":"Brent","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":382828,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70019906,"text":"70019906 - 1997 - Rift-wide correlation of 1.1 Ga Midcontinent rift system basalts: Implications for multiple mantle sources during rift development","interactions":[],"lastModifiedDate":"2023-09-20T20:23:20.593441","indexId":"70019906","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1168,"text":"Canadian Journal of Earth Sciences","active":true,"publicationSubtype":{"id":10}},"title":"Rift-wide correlation of 1.1 Ga Midcontinent rift system basalts: Implications for multiple mantle sources during rift development","docAbstract":"<p><span>Magmatism that accompanied the 1.1 Ga Midcontinent rift system (MRS) is attributed to the upwelling and decompression melting of a mantle plume beneath North America. Five distinctive flood-basalt compositions are recognized in the rift-related basalt succession along the south shore of western Lake Superior, based on stratigraphically correlated major element, trace element, and Nd isotopic analyses. These distinctive compositions can be correlated with equivalent basalt types in comparable stratigraphic positions in other MRS localities around western Lake Superior. Four of these compositions are also recognized at Mamainse Point more than 200 km away in eastern Lake Superior. These regionally correlative basalt compositions provide the basis for determining the sequential contribution of various mantle sources to flood-basalt magmatism during rift development, extending a model originally developed for eastern Lake Superior. In this refined model, the earliest basalts were derived from small degrees of partial melting at great depth of an enriched, ocean-island-type plume mantle source (ε</span><sub>Nd(1100)</sub><span>&nbsp;value of about 0), followed by magmas representing melts from this plume source and interaction with another mantle source, most likely continental lithospheric mantle (ε</span><sub>Nd(1100</sub><span>) &lt; 0). The relative contribution of this second mantle source diminished with time as larger degree partial melts of the plume became the dominant source for the voluminous younger basalts (ε</span><sub>Nd(1100)</sub><span>&nbsp;value of about 0). Towards the end of magmatism, mixtures of melts from the plume and a depleted asthenospheric mantle source became dominant (ε</span><sub>Nd(1100)</sub><span> = 0 to +3).</span></p>","language":"English","publisher":"Canadian Science Publishing","doi":"10.1139/e17-041","issn":"00084077","usgsCitation":"Nicholson, S.W., Shirey, S., Schulz, K.J., and Green, J., 1997, Rift-wide correlation of 1.1 Ga Midcontinent rift system basalts: Implications for multiple mantle sources during rift development: Canadian Journal of Earth Sciences, v. 34, no. 4, p. 504-520, https://doi.org/10.1139/e17-041.","productDescription":"17 p.","startPage":"504","endPage":"520","costCenters":[],"links":[{"id":228027,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Michigan, Wisconsin","otherGeospatial":"Apostle Islands, Isle Royale, Keweenaw Peninsula, Lake Superior","geographicExtents":"{\n  \"type\": 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W.","contributorId":79504,"corporation":false,"usgs":true,"family":"Nicholson","given":"S.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":384337,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Shirey, S.B.","contributorId":69712,"corporation":false,"usgs":true,"family":"Shirey","given":"S.B.","email":"","affiliations":[],"preferred":false,"id":384335,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Schulz, K. J.","contributorId":79131,"corporation":false,"usgs":true,"family":"Schulz","given":"K.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":384336,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Green, J.C.","contributorId":90052,"corporation":false,"usgs":true,"family":"Green","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":384338,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70019729,"text":"70019729 - 1997 - Paleochemistry of Lakes Agassiz and Manitoba based on ostracodes","interactions":[],"lastModifiedDate":"2023-09-20T20:58:43.030181","indexId":"70019729","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1168,"text":"Canadian Journal of Earth Sciences","active":true,"publicationSubtype":{"id":10}},"title":"Paleochemistry of Lakes Agassiz and Manitoba based on ostracodes","docAbstract":"<p><span>The ionic composition and salinity of Lake Manitoba and its late-glacial precursor, Lake Agassiz, changed significantly over the past 11 000 years. The paleochemical record reported here is based on modern analog environments of ostracodes identified in a new 14.5 m core from southern Lake Manitoba. The ionic composition of Lake Manitoba today is dominated by Na</span><sup>+</sup><span>, Cl</span><sup>−</sup><span>, and HC0</span><sub>3</sub><sup>−</sup><span>, with much less Ca</span><sup>2+</sup><span>, Mg</span><sup>2+</sup><span>, and K</span><sup>+</sup><span>. Evaporative concentration of modern Lake Manitoba water would lead to greater salinity and the near depletion of Ca</span><sup>2+</sup><span>&nbsp;due to continued precipitation of calcite. During periods of highest salinity in the Holocene, however, Lake Manitoba supported&nbsp;</span><i>Limnocythere staplini</i><span>. Today this species inhabits waters in which [Ca</span><sup>2+</sup><span>] &gt; [HCO</span><sub>3</sub><sup>−</sup><span>], including springs associated with groundwater in Paleozoic bedrock discharging into Lake Winnipegosis (and eventually, after much dilution, into Lake Manitoba). Further complicating the Holocene record are intervals containing&nbsp;</span><i>Limnocythere friabilis</i><span>&nbsp;that suggest periodic influxes of dilute water, probably from the Assiniboine River, which bypasses Lake Manitoba today. The variations in Holocene paleochemistry indicated by the ostracode record imply changes in the proportion of overland flow plus precipitation relative to groundwater inputs to Lake Manitoba, independent of changes in evaporation relative to precipitation.</span></p>","language":"English","publisher":"Canadian Science Publishing","doi":"10.1139/e17-056","issn":"00084077","usgsCitation":"Curry, B.B., 1997, Paleochemistry of Lakes Agassiz and Manitoba based on ostracodes: Canadian Journal of Earth Sciences, v. 34, no. 5, p. 699-708, https://doi.org/10.1139/e17-056.","productDescription":"10 p.","startPage":"699","endPage":"708","costCenters":[],"links":[{"id":227804,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Canada","state":"Manitoba","otherGeospatial":"Lake Agassiz, Lake Manitoba","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      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,{"id":70019471,"text":"70019471 - 1997 - Southern California Permanent GPS Geodetic Array: Continuous measurements of regional crustal deformation between the 1992 Landers and 1994 Northridge earthquakes","interactions":[],"lastModifiedDate":"2024-07-19T15:52:36.561876","indexId":"70019471","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":"Southern California Permanent GPS Geodetic Array: Continuous measurements of regional crustal deformation between the 1992 Landers and 1994 Northridge earthquakes","docAbstract":"<p><span>The southern California Permanent GPS Geodetic Array (PGGA) was established in 1990 across the Pacific-North America plate boundary to continuously monitor crustal deformation. We describe the development of the array and the time series of daily positions estimated for its first 10 sites in the 19-month period between the June 28, 1992 (</span><i>M</i><sub><i>w</i></sub><span>=7.3), Landers and January 17, 1994 (</span><i>M</i><sub><i>w</i></sub><span>=6.7), Northridge earthquakes. We compare displacement rates at four site locations with those reported by&nbsp;</span><i>Feigl et al.</i><span>&nbsp;[1993], which were derived from an independent set of Global Positioning System (GPS) and very long baseline interferometry (VLBI) measurements collected over nearly a decade prior to the Landers earthquake. The velocity differences for three sites 65–100 km from the earthquake's epicenter are of order of 3–5 mm/yr and are systematically coupled with the corresponding directions of coseismic displacement. The fourth site, 300 km from the epicenter, shows no significant velocity difference. These observations suggest large-scale postseismic deformation with a relaxation time of at least 800 days. The statistical significance of our observations is complicated by our incomplete knowledge of the noise properties of the two data sets; two possible noise models fit the PGGA data equally well as described in the companion paper by&nbsp;</span><i>Zhang et al</i><span>. [this issue]; the pre-Landers data are too sparse and heterogeneous to derive a reliable noise model. Under a fractal white noise model for the PGGA data we find that the velocity differences for all three sites are statistically different at the 99% significance level. A white noise plus flicker noise model results in significance levels of only 94%, 43%, and 88%. Additional investigations of the pre-Landers data, and analysis of longer spans of PGGA data, could have an important effect on the significance of these results and will be addressed in future work.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/97JB01379","issn":"01480227","usgsCitation":"Bock, Y., Wdowinski, S., Fang, P., Zhang, J., Williams, S., Johnson, H., Behr, J., Genrich, J., Dean, J., Van Domselaar, M., Agnew, D., Wyatt, F., Stark, K., Oral, B., Hudnut, K., King, R., Herring, T., Dinardo, S., Young, W., Jackson, D., and Gurtner, W., 1997, Southern California Permanent GPS Geodetic Array: Continuous measurements of regional crustal deformation between the 1992 Landers and 1994 Northridge earthquakes: Journal of Geophysical Research B: Solid Earth, v. 102, no. B8, p. 18013-18033, https://doi.org/10.1029/97JB01379.","productDescription":"21 p.","startPage":"18013","endPage":"18033","numberOfPages":"21","costCenters":[],"links":[{"id":226883,"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":"505b93e0e4b08c986b31a723","contributors":{"authors":[{"text":"Bock, Y.","contributorId":94051,"corporation":false,"usgs":true,"family":"Bock","given":"Y.","email":"","affiliations":[],"preferred":false,"id":382854,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wdowinski, S.","contributorId":20481,"corporation":false,"usgs":true,"family":"Wdowinski","given":"S.","email":"","affiliations":[],"preferred":false,"id":382840,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Fang, P.","contributorId":66865,"corporation":false,"usgs":true,"family":"Fang","given":"P.","email":"","affiliations":[],"preferred":false,"id":382846,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Zhang, Jiahua","contributorId":35479,"corporation":false,"usgs":true,"family":"Zhang","given":"Jiahua","email":"","affiliations":[],"preferred":false,"id":382843,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Williams, S.","contributorId":18514,"corporation":false,"usgs":true,"family":"Williams","given":"S.","email":"","affiliations":[],"preferred":false,"id":382837,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Johnson, H.","contributorId":61163,"corporation":false,"usgs":true,"family":"Johnson","given":"H.","affiliations":[],"preferred":false,"id":382845,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Behr, J.","contributorId":18917,"corporation":false,"usgs":true,"family":"Behr","given":"J.","email":"","affiliations":[],"preferred":false,"id":382839,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Genrich, J.","contributorId":87706,"corporation":false,"usgs":true,"family":"Genrich","given":"J.","affiliations":[],"preferred":false,"id":382851,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Dean, J.","contributorId":26086,"corporation":false,"usgs":true,"family":"Dean","given":"J.","email":"","affiliations":[],"preferred":false,"id":382841,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Van Domselaar, M.","contributorId":94447,"corporation":false,"usgs":true,"family":"Van Domselaar","given":"M.","email":"","affiliations":[],"preferred":false,"id":382855,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Agnew, D.","contributorId":72539,"corporation":false,"usgs":true,"family":"Agnew","given":"D.","email":"","affiliations":[],"preferred":false,"id":382848,"contributorType":{"id":1,"text":"Authors"},"rank":11},{"text":"Wyatt, F.","contributorId":68047,"corporation":false,"usgs":true,"family":"Wyatt","given":"F.","email":"","affiliations":[],"preferred":false,"id":382847,"contributorType":{"id":1,"text":"Authors"},"rank":12},{"text":"Stark, K.","contributorId":92000,"corporation":false,"usgs":true,"family":"Stark","given":"K.","email":"","affiliations":[],"preferred":false,"id":382852,"contributorType":{"id":1,"text":"Authors"},"rank":13},{"text":"Oral, B.","contributorId":80435,"corporation":false,"usgs":true,"family":"Oral","given":"B.","email":"","affiliations":[],"preferred":false,"id":382849,"contributorType":{"id":1,"text":"Authors"},"rank":14},{"text":"Hudnut, K.","contributorId":92439,"corporation":false,"usgs":true,"family":"Hudnut","given":"K.","affiliations":[],"preferred":false,"id":382853,"contributorType":{"id":1,"text":"Authors"},"rank":15},{"text":"King, R.","contributorId":18827,"corporation":false,"usgs":true,"family":"King","given":"R.","affiliations":[],"preferred":false,"id":382838,"contributorType":{"id":1,"text":"Authors"},"rank":16},{"text":"Herring, T.","contributorId":83288,"corporation":false,"usgs":true,"family":"Herring","given":"T.","email":"","affiliations":[],"preferred":false,"id":382850,"contributorType":{"id":1,"text":"Authors"},"rank":17},{"text":"Dinardo, S.","contributorId":49532,"corporation":false,"usgs":true,"family":"Dinardo","given":"S.","email":"","affiliations":[],"preferred":false,"id":382844,"contributorType":{"id":1,"text":"Authors"},"rank":18},{"text":"Young, W.","contributorId":33859,"corporation":false,"usgs":true,"family":"Young","given":"W.","email":"","affiliations":[],"preferred":false,"id":382842,"contributorType":{"id":1,"text":"Authors"},"rank":19},{"text":"Jackson, D.","contributorId":104646,"corporation":false,"usgs":true,"family":"Jackson","given":"D.","affiliations":[],"preferred":false,"id":382857,"contributorType":{"id":1,"text":"Authors"},"rank":20},{"text":"Gurtner, W.","contributorId":103015,"corporation":false,"usgs":true,"family":"Gurtner","given":"W.","email":"","affiliations":[],"preferred":false,"id":382856,"contributorType":{"id":1,"text":"Authors"},"rank":21}]}}
,{"id":70019728,"text":"70019728 - 1997 - Moment-tensor solutions estimated using optimal filter theory: Global seismicity, 1995","interactions":[],"lastModifiedDate":"2013-01-22T15:38:06","indexId":"70019728","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3071,"text":"Physics of the Earth and Planetary Interiors","active":true,"publicationSubtype":{"id":10}},"title":"Moment-tensor solutions estimated using optimal filter theory: Global seismicity, 1995","docAbstract":"Moment-tensor solutions, estimated using optimal filter theory, are listed for 241 moderate-to-large size earthquakes that occurred during 1995. ?? 1997 Published by Elsevier Science B.V.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Physics of the Earth and Planetary Interiors","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/S0031-9201(96)03266-9","issn":"00319201","usgsCitation":"Sipkin, S., and Zirbes, M., 1997, Moment-tensor solutions estimated using optimal filter theory: Global seismicity, 1995: Physics of the Earth and Planetary Interiors, v. 101, no. 3-4, p. 291-301, https://doi.org/10.1016/S0031-9201(96)03266-9.","startPage":"291","endPage":"301","numberOfPages":"11","costCenters":[],"links":[{"id":227803,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":266261,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0031-9201(96)03266-9"}],"volume":"101","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5d40e4b0c8380cd70260","contributors":{"authors":[{"text":"Sipkin, S.A.","contributorId":9399,"corporation":false,"usgs":true,"family":"Sipkin","given":"S.A.","email":"","affiliations":[],"preferred":false,"id":383727,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Zirbes, M.D.","contributorId":27620,"corporation":false,"usgs":true,"family":"Zirbes","given":"M.D.","email":"","affiliations":[],"preferred":false,"id":383728,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70019831,"text":"70019831 - 1997 - Seasonal Sea-Level Variations in San Francisco Bay in Response to Atmospheric Forcing, 1980","interactions":[],"lastModifiedDate":"2016-07-27T13:05:57","indexId":"70019831","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1587,"text":"Estuarine, Coastal and Shelf Science","active":true,"publicationSubtype":{"id":10}},"title":"Seasonal Sea-Level Variations in San Francisco Bay in Response to Atmospheric Forcing, 1980","docAbstract":"<p>The seasonal response of sea level in San Francisco Bay (SFB) to atmospheric forcing during 1980 is investigated. The relations between sea-level data from the Northern Reach, Central Bay and South Bay, and forcing by local wind stresses, sea level pressure (SLP), runoff and the large scale sea level pressure field are examined in detail. The analyses show that the sea-level elevations and slopes respond to the along-shore wind stress T(V) at most times of the year, and to the cross-shore wind stress T(N) during two transition periods in spring and autumn. River runoff raises the sea-level elevation during winter. It is shown that winter precipitation in the SFB area is mainly attributed to the atmospheric circulation associated with the Alcutian Low, which transports the warm, moist air into the Bay area. A multiple linear regression model is employed to estimate the independent contributions of barometric pressure and wind stress to adjusted sea level. These calculations have a simple dynamical interpretation which confirms the importance of along-shore wind to both sea level and north-south slope within the Bay.</p>","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Estuarine, Coastal and Shelf Science","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1006/ecss.1996.0162","issn":"02727714","usgsCitation":"Wang, J., Cheng, R.T., and Smith, P., 1997, Seasonal Sea-Level Variations in San Francisco Bay in Response to Atmospheric Forcing, 1980: Estuarine, Coastal and Shelf Science, v. 45, no. 1, p. 39-52, https://doi.org/10.1006/ecss.1996.0162.","startPage":"39","endPage":"52","numberOfPages":"14","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":479016,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1006/ecss.1996.0162","text":"Publisher Index Page"},{"id":228255,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206087,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1006/ecss.1996.0162"}],"volume":"45","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b885ee4b08c986b316935","contributors":{"authors":[{"text":"Wang, Jingyuan","contributorId":10771,"corporation":false,"usgs":false,"family":"Wang","given":"Jingyuan","email":"","affiliations":[],"preferred":false,"id":384097,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cheng, R. T.","contributorId":23138,"corporation":false,"usgs":false,"family":"Cheng","given":"R.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":384098,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Smith, P.C.","contributorId":27625,"corporation":false,"usgs":true,"family":"Smith","given":"P.C.","email":"","affiliations":[],"preferred":false,"id":384099,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70019450,"text":"70019450 - 1997 - A numerical model of sediment transport applied to San Francisco Bay, California","interactions":[],"lastModifiedDate":"2016-07-27T12:33:11","indexId":"70019450","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2378,"text":"Journal of Marine Environmental Engineering","onlineIssn":"1029-0427","printIssn":"1061-026X","active":true,"publicationSubtype":{"id":10}},"title":"A numerical model of sediment transport applied to San Francisco Bay, California","docAbstract":"<p>A two dimensional depth-averaged sediment transport model is used to simulate field measurements of suspended sediment concentrations in northern San Francisco Bay. The model uses a semi-implicit finite difference method to solve the shallow water equations and incorporates standard empirical expressions for erosion and deposition of sediments into the transport equation as source/sink terms. The field measurements indicate that tidal scale variations (both diurnal and spring-neap) dominate the variations in suspended sediment concentration (SSC). Increases in SSC also correlated highly with large delta outflows following a storm in late winter. The sediment transport model reproduces the field measurements quite well during periods when the water column is relatively well-mixed vertically. However, the present model only includes one size class of sediment and does not perform well when spatial variability of sediment properties and multiple size classes are significant factors. Comparison of erosion and accretion patterns generated by the model with those obtained from historical bathymetric surveys indicate that the model captures several of the general features observed historically. A sensitivity analysis demonstrates that the model is very sensitive to the critical shear stress for erosion and moderately sensitive to the erosion rate constant, critical shear stress for deposition, and settling velocity.</p>","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Marine Environmental Engineering","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"1061026X","usgsCitation":"Mcdonald, E., and Cheng, R.T., 1997, A numerical model of sediment transport applied to San Francisco Bay, California: Journal of Marine Environmental Engineering, v. 4, no. 1, p. 1-41.","startPage":"1","endPage":"41","numberOfPages":"41","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":226749,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"4","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e4c9e4b0c8380cd46922","contributors":{"authors":[{"text":"Mcdonald, E.T.","contributorId":27621,"corporation":false,"usgs":true,"family":"Mcdonald","given":"E.T.","email":"","affiliations":[],"preferred":false,"id":382769,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cheng, R. T.","contributorId":23138,"corporation":false,"usgs":false,"family":"Cheng","given":"R.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":382768,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70019557,"text":"70019557 - 1997 - Debris-flow mobilization from landslides","interactions":[],"lastModifiedDate":"2023-02-24T17:58:41.67217","indexId":"70019557","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":806,"text":"Annual Review of Earth and Planetary Sciences","active":true,"publicationSubtype":{"id":10}},"title":"Debris-flow mobilization from landslides","docAbstract":"<p><span>Field observations, laboratory experiments, and theoretical analyses indicate that landslides mobilize to form debris flows by three processes: (</span><i>a</i><span>) widespread Coulomb failure within a sloping soil, rock, or sediment mass, (</span><i>b</i><span>) partial or complete liquefaction of the mass by high pore-fluid pressures, and (</span><i>c</i><span>) conversion of landslide translational energy to internal vibrational energy (i.e. granular temperature). These processes can operate independently, but in many circumstances they appear to operate simultaneously and synergistically. Early work on debris-flow mobilization described a similar interplay of processes but relied on mechanical models in which debris behavior was assumed to be fixed and governed by a Bingham or Bagnold rheology. In contrast, this review emphasizes models in which debris behavior evolves in response to changing pore pressures and granular temperatures. One-dimensional infinite-slope models provide insight by quantifying how pore pressures and granular temperatures can influence the transition from Coulomb failure to liquefaction. Analyses of multidimensional experiments reveal complications ignored in one-dimensional models and demonstrate that debris-flow mobilization may occur by at least two distinct modes in the field.</span></p>","language":"English","publisher":"Annual Reviews","doi":"10.1146/annurev.earth.25.1.85","usgsCitation":"Iverson, R.M., Reid, M.E., and Lahusen, R.G., 1997, Debris-flow mobilization from landslides: Annual Review of Earth and Planetary Sciences, v. 25, p. 85-138, https://doi.org/10.1146/annurev.earth.25.1.85.","productDescription":"54 p.","startPage":"85","endPage":"138","numberOfPages":"54","costCenters":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"links":[{"id":227713,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fdfce4b0c8380cd4ea50","contributors":{"authors":[{"text":"Iverson, Richard M. 0000-0002-7369-3819 riverson@usgs.gov","orcid":"https://orcid.org/0000-0002-7369-3819","contributorId":536,"corporation":false,"usgs":true,"family":"Iverson","given":"Richard","email":"riverson@usgs.gov","middleInitial":"M.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true},{"id":615,"text":"Volcano Hazards Program","active":true,"usgs":true}],"preferred":true,"id":383163,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reid, Mark E. 0000-0002-5595-1503 mreid@usgs.gov","orcid":"https://orcid.org/0000-0002-5595-1503","contributorId":1167,"corporation":false,"usgs":true,"family":"Reid","given":"Mark","email":"mreid@usgs.gov","middleInitial":"E.","affiliations":[{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true},{"id":617,"text":"Volcano Science Center","active":true,"usgs":true},{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"preferred":true,"id":383165,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lahusen, Richard G. rlahusen@usgs.gov","contributorId":535,"corporation":false,"usgs":true,"family":"Lahusen","given":"Richard","email":"rlahusen@usgs.gov","middleInitial":"G.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"preferred":true,"id":383164,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70019488,"text":"70019488 - 1997 - Postseismic strain following the 1989 Loma Prieta earthquake from GPS and leveling measurements","interactions":[],"lastModifiedDate":"2024-07-31T16:55:09.241719","indexId":"70019488","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":"Postseismic strain following the 1989 Loma Prieta earthquake from GPS and leveling measurements","docAbstract":"<p><span>Postseismic deformation in the 5 years following the 1989 Loma Prieta earthquake has been measured with the Global Positioning System and precise leveling. Postearthquake velocities at distances greater than ∼20 km from the coseismic rupture are not significantly different from those observed in the 20 years prior to the earthquake. However, velocities at stations within ∼20 km of the rupture exceed preearthquake rates and exhibit unanticipated contraction normal to the strike of the San Andreas fault system. A combination of forward modeling and nonlinear optimization suggests that the observed postseismic deformations were caused by aseismic oblique reverse slip averaging 2.9 cm/yr on the San Andreas fault and/or the Loma Prieta rupture zone and 2.4 cm/yr reverse slip along a buried fault within the Foothills thrust belt. The best fitting sources of postseismic deformation are all located at depths of less than 15 km. We find no evidence for accelerated flow or shear below the Loma Prieta rupture in the first 5 years following the earthquake. The inferred postseismic slip is likely to have been caused by the coseismic stress change updip of the 1989 rupture.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/96JB03171","issn":"01480227","usgsCitation":"Burgmann, R., Segall, P., Lisowski, M., and Svarc, J., 1997, Postseismic strain following the 1989 Loma Prieta earthquake from GPS and leveling measurements: Journal of Geophysical Research B: Solid Earth, v. 102, no. B3, p. 4933-4955, https://doi.org/10.1029/96JB03171.","productDescription":"23 p.","startPage":"4933","endPage":"4955","numberOfPages":"23","costCenters":[],"links":[{"id":479967,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/96jb03171","text":"Publisher Index Page"},{"id":226338,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"102","issue":"B3","noUsgsAuthors":false,"publicationDate":"1997-03-10","publicationStatus":"PW","scienceBaseUri":"505a7e9ae4b0c8380cd7a63f","contributors":{"authors":[{"text":"Burgmann, R.","contributorId":10167,"corporation":false,"usgs":true,"family":"Burgmann","given":"R.","affiliations":[],"preferred":false,"id":382921,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Segall, P.","contributorId":44231,"corporation":false,"usgs":false,"family":"Segall","given":"P.","affiliations":[],"preferred":false,"id":382922,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lisowski, M.","contributorId":70381,"corporation":false,"usgs":true,"family":"Lisowski","given":"M.","email":"","affiliations":[],"preferred":false,"id":382923,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Svarc, J.","contributorId":85731,"corporation":false,"usgs":true,"family":"Svarc","given":"J.","affiliations":[],"preferred":false,"id":382924,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70019754,"text":"70019754 - 1997 - Long-period events, the most characteristic seismicity accompanying the emplacement and extrusion of a lava dome in Galeras Volcano, Colombia, in 1991","interactions":[],"lastModifiedDate":"2012-03-12T17:19:18","indexId":"70019754","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","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":"Long-period events, the most characteristic seismicity accompanying the emplacement and extrusion of a lava dome in Galeras Volcano, Colombia, in 1991","docAbstract":"Since its reactivation in 1988 the principal eruptions of Galeras Volcano occurred on May 4-9, 1989, July 16, 1992, and January 14, March 23, April 3, April 14 and June 7, 1993. The initial eruption was a phreatic event which clearly marked a new period of activity. A lava dome was extruded within the main crater in October 1991 and subsequently destroyed in an explosive eruption on July 16, 1992. The eruptions that followed were all vulcanian-type explosions. The seismicity accompanying the emplacement, extrusion, and destruction of the lava dome was dominated by a mix of long-period (LP) events and tremor displaying a variety of waveforms. Repetitive LP events with dominant periods in the range 0.2-1 s were observed in October and November 1991 and visually correlated with short energetic pulses of gas venting through a crack bisecting the dome surface. Each LP event was characterized by a weak precursory signal with dominant periods in the range 0.05-0.1 s lasting roughly 7 s. Using the fluid-driven crack model of Chouet (1988, 1992), we infer that two distinct cracks may have acted as sources for the LP and precursor signals. Spectral analyses of the data yield the following parameters for the LP source: crack length, 240-360 m; crack width, 130-150 m; crack aperture, 0.5-3.4 mm; crack stiffness, 100-500; sound speed of fluid, 880 m/s; and excess pressure, 0.01-0.19 MPa. Similar analyses yield the parameters of the precursor source: crack length, 20-30 m; crack width, 15-25 m; crack aperture, 2.3-8.7 mm; crack stiffness, 5-15; sound speed of fluid, 140 m/s; and excess pressure, 0.06-0.15 MPa. Combined with geologic and thermodynamic constraints obtained from field observations, these seismic parameters suggest a gas-release mechanism in which the episodic collapse of a foam layer trapped at the top of the magma column subjacent to the dome releases a slug of pressurized gas which escapes to the surface while dilating a preexisting system of cracks in the dome structure. Accordingly, the fracture observed on the crystallized dome body is the surface extension of the LP-source crack, where LP activity is induced by the rapid emission and expansion of gas flowing through this conduit. The width and aperture of the crack estimated in the model are in good agreement with the length and aperture of the fracture estimated from visual observations. The source parameters of the precursor signal are suggestive of a nozzle-like conduit connecting the LP-source crack to the underlying magma reservoir. Excitation of this conduit segment is attributed to the rapid emission and acceleration of the frothy fluid resulting from the collapse of the foam layer at the top of the reservoir. The calculated periodicity of foam collapse events is in agreement with the observed average rate of thirteen LP events per hour.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Volcanology and Geothermal Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"03770273","usgsCitation":"Gil, C.F., and Chouet, B., 1997, Long-period events, the most characteristic seismicity accompanying the emplacement and extrusion of a lava dome in Galeras Volcano, Colombia, in 1991: Journal of Volcanology and Geothermal Research, v. 77, no. 1-4, p. 121-158.","startPage":"121","endPage":"158","numberOfPages":"38","costCenters":[],"links":[{"id":228290,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"77","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a496ee4b0c8380cd685d5","contributors":{"authors":[{"text":"Gil, Cruz F.","contributorId":86646,"corporation":false,"usgs":true,"family":"Gil","given":"Cruz","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":383810,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chouet, B. A.","contributorId":31813,"corporation":false,"usgs":true,"family":"Chouet","given":"B. A.","affiliations":[],"preferred":false,"id":383809,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70019570,"text":"70019570 - 1997 - The role of mesocosm studies in ecological risk analysis","interactions":[],"lastModifiedDate":"2017-02-01T11:07:14","indexId":"70019570","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1450,"text":"Ecological Applications","active":true,"publicationSubtype":{"id":10}},"title":"The role of mesocosm studies in ecological risk analysis","docAbstract":"<p><span>Mesocosms have been primarily used as research tools for the evaluation of the fate and effects of xenobiotic chemicals at the population, community, and ecosystem levels of biological organization. This paper provides suggestions for future applications of mesocosm research. Attention should be given to the configuration of mesocosm parameters to explicitly study regional questions of ecological interest. The initial physical, chemical, and biological conditions within mesocosms should be considered as factors shaping the final results of experiments. Certain fundamental questions such as the ecological inertia and resilience of systems with different initial ecological properties should be addressed. Researchers should develop closer working relationships with mathematical modelers in linking computer models to the outcomes of mesocosm studies. Mesocosm tests, linked with models, could enable managers and regulators to forecast the regional consequences of chemicals released into the environment.</span></p>","language":"English","publisher":"Ecological Society of America","doi":"10.1890/1051-0761(1997)007[1099:TROMSI]2.0.CO;2","issn":"10510761","usgsCitation":"Boyle, T., and Fairchild, J., 1997, The role of mesocosm studies in ecological risk analysis: Ecological Applications, v. 7, no. 4, p. 1099-1102, https://doi.org/10.1890/1051-0761(1997)007[1099:TROMSI]2.0.CO;2.","productDescription":"4 p.","startPage":"1099","endPage":"1102","numberOfPages":"4","costCenters":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"links":[{"id":227919,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"7","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baf82e4b08c986b324851","contributors":{"authors":[{"text":"Boyle, Terence P.","contributorId":85214,"corporation":false,"usgs":true,"family":"Boyle","given":"Terence P.","affiliations":[],"preferred":false,"id":383203,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fairchild, James F.","contributorId":178203,"corporation":false,"usgs":false,"family":"Fairchild","given":"James F.","affiliations":[],"preferred":false,"id":383204,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
]}