Concentrations of Ag, Al, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn were determined in six sediment cores from San Francisco Bay (SFB) and one sediment core in Tomales Bay (TB), a reference estuary. SFB cores were collected from between the head of the estuary and its mouth (Grizzly Bay, GB; San Pablo Bay, SP; Central Bay, CB; Richardson Bay, RB, respectively) and ranged in length from 150 to 250 cm. Concentrations of Cr, V and Ni are greater than mean crustal content in SFB and TB sediments, and greater than found in many other coastal sediments. However, erosion of ultramafic rock formations in the watershed appears to be the predominant source. Baseline concentrations of other metals were determined from horizons deposited before sediments were influenced by human activities and by comparing concentrations to those in TB. Baseline concentrations of Cu co-varied with Al in the SFB sediments and ranged from 23.7±1.2 μg/g to 41.4±2.4 μg/g. Baseline concentrations of other metals were less variable: Ag, 0.09±0.02 μg/g; Pb, 5.2±0.7 μg/g; Hg, 0.06±0.01 μg/g; Zn, 78±7 μg/g. The earliest anthropogenic influence on metal concentrations appeared as Hg contamination (0.3–0.4 μg/g) in sediments deposited at SP between 1850 and 1880, apparently associated with debris from hydraulic gold mining. Maximum concentrations of Hg within the cores were 20 times baseline. Greater inventories of Hg at SP and GB than at RB verified the importance of mining in the watershed as a source. Enrichment of Ag, Pb, Cu and Zn first appeared after 1910 in the RB core, later than is observed in Europe or eastern North America. Maximum concentrations of Ag and Pb were 5–10 times baseline and Cu and Zn concentrations were less than three times baseline. Large inventories of Pb to the sediments in the GB and SP cores appeared to be the result of the proximity to a large Pb smelter. Inventories of Pb at RB are similar to those typical of atmospheric inputs, although influence from the Pb smelter is also suspected. Concentrations of Hg and Pb have decreased since the 1970s (to 0.30 μg/g and 25 μg/g, respectively) and were similar among all cores in 1990. Early Ag contamination was perhaps a byproduct of the Pb smelting process, but a modern source of Ag is also indicated, especially at RB and CB.
Probabilistic seismic hazard analysis (PSHA) is a technique for estimating the annual rate of exceedance of a specified ground motion at a site due to known and suspected earthquake sources. The relative contributions of the various sources to the total seismic hazard are determined as a function of their occurrence rates and their ground-motion potential. The separation of the exceedance contributions into bins whose base dimensions are magnitude and distance is called deaggregation. We have deaggregated the hazard analyses for the new USGS national probabilistic ground-motion hazard maps (Frankel et al., 1996). For points on a 0.2° grid in the central and eastern United States (CEUS), we show color maps of the geographical variation of mean and modal magnitudes (M, Mˇ) and distances (D, Dˇ) for ground motions having a 2% chance of exceedance in 50 years. These maps are displayed for peak horizontal acceleration and for spectral response accelerations of 0.2, 0.3, and 1.0 sec. We tabulate M, D, Mˇ, and Dˇ for 49 CEUS cities for 0.2- and 1.0-sec response. Thus, these maps and tables are PSHA-derived estimates of the potential earthquakes that dominate seismic hazard at short and intermediate periods in the CEUS.
","language":"English","publisher":"Seismological Society of America","doi":"10.1785/BSSA0890010001","issn":"00371106","usgsCitation":"Harmsen, S., Perkins, D., and Frankel, A., 1999, Deaggregation of probabilistic ground motions in the central and eastern United States: Bulletin of the Seismological Society of America, v. 89, no. 1, p. 1-13, https://doi.org/10.1785/BSSA0890010001.","productDescription":"13 p.","startPage":"1","endPage":"13","numberOfPages":"13","costCenters":[],"links":[{"id":421943,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.geoscienceworld.org/ssa/bssa/article/89/1/1/120360/Deaggregation-of-probabilistic-ground-motions-in"},{"id":229343,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -98.35529324972059,\n 50.267706320710346\n ],\n [\n -98.35529324972059,\n 24.81584356675542\n ],\n [\n -66.01154324972084,\n 24.81584356675542\n ],\n [\n -66.01154324972084,\n 50.267706320710346\n ],\n [\n -98.35529324972059,\n 50.267706320710346\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"89","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fdeae4b0c8380cd4e9f1","contributors":{"authors":[{"text":"Harmsen, S.","contributorId":79600,"corporation":false,"usgs":true,"family":"Harmsen","given":"S.","affiliations":[],"preferred":false,"id":391653,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Perkins, D.","contributorId":83589,"corporation":false,"usgs":true,"family":"Perkins","given":"D.","affiliations":[],"preferred":false,"id":391654,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Frankel, A. 0000-0001-9119-6106","orcid":"https://orcid.org/0000-0001-9119-6106","contributorId":41593,"corporation":false,"usgs":true,"family":"Frankel","given":"A.","affiliations":[],"preferred":false,"id":391652,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022004,"text":"70022004 - 1999 - Pumping tests in networks of multilevel sampling wells: Motivation and methodology","interactions":[],"lastModifiedDate":"2018-03-20T14:49:58","indexId":"70022004","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","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":"Pumping tests in networks of multilevel sampling wells: Motivation and methodology","docAbstract":"The identification of spatial variations in hydraulic conductivity (K) on a scale of relevance for transport investigations has proven to be a considerable challenge. Recently, a new field method for the estimation of interwell variations in K has been proposed. This method, hydraulic tomography, essentially consists of a series of short‐term pumping tests performed in a tomographic‐like arrangement. In order to fully realize the potential of this approach, information about lateral and vertical variations in pumping‐induced head changes (drawdown) is required with detail that has previously been unobtainable in the field. Pumping tests performed in networks of multilevel sampling (MLS) wells can provide data of the needed density if drawdown can accurately and rapidly be measured in the small‐diameter tubing used in such wells. Field and laboratory experiments show that accurate transient drawdown data can be obtained in the small‐diameter MLS tubing either directly with miniature fiber‐optic pressure sensors or indirectly using air‐pressure transducers. As with data from many types of hydraulic tests, the quality of drawdown measurements from MLS tubing is quite dependent on the effectiveness of well development activities. Since MLS ports of the standard design are prone to clogging and are difficult to develop, alternate designs are necessary to ensure accurate drawdown measurements. Initial field experiments indicate that drawdown measurements obtained from pumping tests performed in MLS networks have considerable potential for providing valuable information about spatial variations in hydraulic conductivity.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/1999WR900231","usgsCitation":"Butler, J., McElwee, C., and Bohling, G.C., 1999, Pumping tests in networks of multilevel sampling wells: Motivation and methodology: Water Resources Research, v. 35, no. 11, p. 3553-3560, https://doi.org/10.1029/1999WR900231.","productDescription":"8 p.","startPage":"3553","endPage":"3560","costCenters":[],"links":[{"id":479598,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/1999wr900231","text":"Publisher Index Page"},{"id":229167,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"35","issue":"11","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a9034e4b0c8380cd7fbc7","contributors":{"authors":[{"text":"Butler, J.J. Jr.","contributorId":12194,"corporation":false,"usgs":true,"family":"Butler","given":"J.J.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":392010,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McElwee, C.D.","contributorId":66408,"corporation":false,"usgs":true,"family":"McElwee","given":"C.D.","affiliations":[],"preferred":false,"id":392012,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bohling, Geoffrey C.","contributorId":43109,"corporation":false,"usgs":false,"family":"Bohling","given":"Geoffrey","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":392011,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022133,"text":"70022133 - 1999 - Mobilization and attenuation of metals downstream from a base-metal mining site in the Matra Mountains, northeastern Hungary","interactions":[],"lastModifiedDate":"2012-03-12T17:19:46","indexId":"70022133","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2302,"text":"Journal of Geochemical Exploration","active":true,"publicationSubtype":{"id":10}},"title":"Mobilization and attenuation of metals downstream from a base-metal mining site in the Matra Mountains, northeastern Hungary","docAbstract":"Regional geochemical baseline values have been established for Hungary by the use of low-density stream-sediment surveys of flood-plain deposits of large drainage basins and of the fine fraction of stream sediments. The baseline values and anomaly thresholds thus produced helped to evaluate the importance of high toxic element concentrations found in soils in a valley downstream of a polymetallic vein-type base-metal mine. Erosion of the mine dumps and flotation dump, losses of metals during filtering, storage and transportation, human neglects, and operational breakdowns, have all contributed to the contamination of a small catchment basin in a procession of releases of solid waste. The sulfide-rich waste material weathers to a yellow color; this layer of 'yellow sand' blankets a narrow strip of the floodplain of Toka Creek in the valley near the town of Gyongyosoroszi. Contamination was spread out in the valley by floods. Metals present in the yellow sand include Pb, As, Cd, Cu, Zn, and Sb. Exposure of the local population to these metals may occur through inhalation of airborne particulates or by ingestion of these metals that are taken up by crops grown in the valley. To evaluate the areal extent and depth of the contamination, active stream sediment, flood-plain deposits, lake or reservoir sediments, soils, and surface water were sampled along the erosion pathways downstream of the mine and dumps. The flood-plain profile was sampled in detail to see the vertical distribution of elements and to relate the metal concentrations to the sedimentation and contamination histories of the flood plain. Downward migration of mobile Zn and Cd from the contaminated upper layers under supergene conditions is observed, while vertical migration of Pb, As, Hg and Sb appears to be insignificant. Soil profiles of 137Cs which originated from above-ground atomic bomb tests and the Chernobyl accident, provide good evidence that the upper 30-40 cm of the flood-plain sections, which includes the yellow sand contamination, were deposited in the last 30-40 years.The regional geochemical baseline values are established for Hungary using low-density stream-sediment surveys of flood-plain deposits of large drainage basins and of the fine fraction of stream sediments. The baseline values and anomaly thresholds allowed the evaluation of the importance of high toxic element concentrations in soils in a valley, downstream of a polymetallic vein-type base-metal mine. The metals present in the yellow sand include Pb, As, Cd, Cu, Zn and Sb. To evaluate the areal extent and depth of the contamination, active stream sediment, flood-plain deposits, lake or reservoir sediments, the soils and surface water were sampled along the erosion pathways downstream of the mine and dumps.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Geochemical Exploration","largerWorkSubtype":{"id":10,"text":"Journal Article"},"conferenceTitle":"Proceedings of the 1997 4th International Symposium on Environmental Geochemistry, ISEG. Part 2 (of 2)","conferenceDate":"5 October 1997 through 10 October 1997","conferenceLocation":"Vail, CO, USA","language":"English","publisher":"Elsevier Sci B.V.","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/S0375-6742(98)00056-9","issn":"03756742","usgsCitation":"Odor, L., Wanty, R., Horvath, I., and Fugedi, U., 1999, Mobilization and attenuation of metals downstream from a base-metal mining site in the Matra Mountains, northeastern Hungary: Journal of Geochemical Exploration, v. 65, no. 1 pt 2, p. 47-60, https://doi.org/10.1016/S0375-6742(98)00056-9.","startPage":"47","endPage":"60","numberOfPages":"14","costCenters":[],"links":[{"id":206734,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0375-6742(98)00056-9"},{"id":230664,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"65","issue":"1 pt 2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5b95e4b0c8380cd6f667","contributors":{"editors":[{"text":"Gough L.P.Marsh S.P.","contributorId":128372,"corporation":true,"usgs":false,"organization":"Gough L.P.Marsh S.P.","id":536476,"contributorType":{"id":2,"text":"Editors"},"rank":1}],"authors":[{"text":"Odor, L.","contributorId":39156,"corporation":false,"usgs":true,"family":"Odor","given":"L.","email":"","affiliations":[],"preferred":false,"id":392481,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wanty, R. B. 0000-0002-2063-6423","orcid":"https://orcid.org/0000-0002-2063-6423","contributorId":66704,"corporation":false,"usgs":true,"family":"Wanty","given":"R. B.","affiliations":[],"preferred":false,"id":392483,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Horvath, I.","contributorId":18133,"corporation":false,"usgs":true,"family":"Horvath","given":"I.","email":"","affiliations":[],"preferred":false,"id":392480,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Fugedi, U.","contributorId":46713,"corporation":false,"usgs":true,"family":"Fugedi","given":"U.","email":"","affiliations":[],"preferred":false,"id":392482,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70022029,"text":"70022029 - 1999 - Spatial and temporal patterns of nonindigenous fish introductions in the United States","interactions":[],"lastModifiedDate":"2016-01-05T09:38:30","indexId":"70022029","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1657,"text":"Fisheries","onlineIssn":"1548-8446","printIssn":"0363-2415","active":true,"publicationSubtype":{"id":10}},"title":"Spatial and temporal patterns of nonindigenous fish introductions in the United States","docAbstract":"In 1978 biologists in Gainesville, Florida, began compiling records on the distribution and status of nonindigenous fishes known in U.S. inland waters. The database, now in electronic format, currently contains approximately 17,000 records representing more than 500 nonindigenous fish taxa (i.e., species, hybrids, and unidentified forms). Of these taxa, 317 (61%) are native to the United States but have been introduced by humans into U.S. drainages outside their natural geographic ranges; 185 (35%) are fishes introduced from foreign countries; and 22 (4%) are hybrids. Of the introduced foreign fish taxa, 71 (38%) are species that have established (i.e., reproducing) or possibly established populations in open U.S. waters. The database is a useful tool for natural resource managers and other decision makers. Although we periodically revise records and constantly enter new ones, our database is fairly updated; thus, we are able to more thoroughly analyze patterns of introduction and the spread of nonindigenous fishes within the United States. Moreover, information gaps exposed by the data set should serve to stimulate and guide future research on nonindigenous fishes. This paper introduces our database and provides an overview of temporal and spatial patterns of nonindigenous fish distributions in U.S. inland waters.
","language":"English","publisher":"Elsevier","doi":"10.1577/1548-8446(1999)024<0016:SATPON>2.0.CO;2","issn":"03632415","usgsCitation":"Nico, L., and Fuller, P., 1999, Spatial and temporal patterns of nonindigenous fish introductions in the United States: Fisheries, v. 24, no. 1, p. 16-27, https://doi.org/10.1577/1548-8446(1999)024<0016:SATPON>2.0.CO;2.","productDescription":"12 p.","startPage":"16","endPage":"27","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":230849,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"24","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9441e4b08c986b31a977","contributors":{"authors":[{"text":"Nico, L.G. 0000-0002-4488-7737","orcid":"https://orcid.org/0000-0002-4488-7737","contributorId":83052,"corporation":false,"usgs":true,"family":"Nico","given":"L.G.","affiliations":[],"preferred":false,"id":392084,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fuller, P.L. 0000-0002-9389-9144","orcid":"https://orcid.org/0000-0002-9389-9144","contributorId":68245,"corporation":false,"usgs":true,"family":"Fuller","given":"P.L.","affiliations":[],"preferred":false,"id":392083,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022030,"text":"70022030 - 1999 - The Bear Brook Watershed, Maine (BBWM), USA","interactions":[],"lastModifiedDate":"2012-03-12T17:19:43","indexId":"70022030","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1552,"text":"Environmental Monitoring and Assessment","onlineIssn":"1573-2959","printIssn":"0167-6369","active":true,"publicationSubtype":{"id":10}},"title":"The Bear Brook Watershed, Maine (BBWM), USA","docAbstract":"The Bear Brook Watershed Manipulation project in Maine is a paired calibrated watershed study funded by the U.S. EPA. The research program is evaluating whole ecosystem response to elevated inputs of acidifying chemicals. The consists of a 2.5 year calibration period (1987-1989), nine years of chemical additions of (NH4)2SO4 (15N- and 34S-enriched for several years) to West Bear watershed (1989-1998), followed by a recovery period. The other watershed, East Bear, serves as a reference. Dosing is in six equal treatments/yr of 1800 eq SO4 and NH4/ha/yr, a 200% increase over 1988 loading (wet plus dry) for SO4 300% for N (wet NO3 + NH4). The experimental and reference watersheds are forested with mixed hard- and softwoods, and have thin acidic soils, areas of 10.2 and 10.7 ha and relief of 210 m. Thin till of variable composition is underlain by metasedimentary pelitic rocks and calc-silicate gneiss intruded by granite dikes and sills. For the period 1987-1995, precipitation averaged 1.4 m/yr, had a mean pH of 4.5, with SO4, NO3, and NH4 concentrations of 26, 14, and 7 ??eq/L, respectively. The nearly perrenial streams draining each watershed have discharges ranging from 0 (East Bear stops flowing for one to two months per year) to 150 L/sec. Prior to manipulation, East Bear and West Bear had a volume weighted annual mean pH of approximately 5.4, alkalinity = 0 to 4 ??eq/L, total base cations = 184 ??eq/L (sea-salt corrected = 118 ??eq/L), and SO4 = 100 to 111 ??eq/L. Nitrate ranged from 0 to 30 ??eq/L with an annual mean of 6 to 25 ??eq/L; dissolved organic carbon (DOC) ranged from 1 to 7 mg/L but was typically less than 3. Episodic acidification occurred at high discharge and was caused by dilution of cations, slightly increased DOC, significantly higher NO3, and the sea-salt effect. Depressions in pH were accompanied by increases in inorganic Al. The West Bear catchment responded to the chemical additions with increased export of base cations, Al, SO4, NO3, and decreased pH, ANC, and DOC. Silica remained relatively constant. Neutralization of the acidifying chemicals occurred dominantly by cation desorption and mobilization of Al.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Monitoring and Assessment","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Kluwer Academic Publishers","publisherLocation":"Dordrecht, Netherlands","doi":"10.1023/A:1006115011381","issn":"01676369","usgsCitation":"Norton, S., Kahl, J., Fernandez, I., Haines, T., Rustad, L., Nodvin, S., Scofield, J., Strickland, T., Erickson, H., Wigington, P., and Lee, J., 1999, The Bear Brook Watershed, Maine (BBWM), USA: Environmental Monitoring and Assessment, v. 55, no. 1, p. 7-51, https://doi.org/10.1023/A:1006115011381.","startPage":"7","endPage":"51","numberOfPages":"45","costCenters":[],"links":[{"id":206831,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1006115011381"},{"id":230886,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"55","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba698e4b08c986b3211fe","contributors":{"authors":[{"text":"Norton, S.","contributorId":45671,"corporation":false,"usgs":true,"family":"Norton","given":"S.","affiliations":[],"preferred":false,"id":392091,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kahl, J.","contributorId":32486,"corporation":false,"usgs":true,"family":"Kahl","given":"J.","affiliations":[],"preferred":false,"id":392088,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Fernandez, I.","contributorId":33881,"corporation":false,"usgs":true,"family":"Fernandez","given":"I.","affiliations":[],"preferred":false,"id":392089,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Haines, T.","contributorId":12401,"corporation":false,"usgs":true,"family":"Haines","given":"T.","email":"","affiliations":[],"preferred":false,"id":392085,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Rustad, L.","contributorId":98687,"corporation":false,"usgs":true,"family":"Rustad","given":"L.","affiliations":[],"preferred":false,"id":392095,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Nodvin, S.","contributorId":67686,"corporation":false,"usgs":true,"family":"Nodvin","given":"S.","email":"","affiliations":[],"preferred":false,"id":392093,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Scofield, J.","contributorId":17187,"corporation":false,"usgs":true,"family":"Scofield","given":"J.","email":"","affiliations":[],"preferred":false,"id":392086,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Strickland, T.","contributorId":68918,"corporation":false,"usgs":true,"family":"Strickland","given":"T.","email":"","affiliations":[],"preferred":false,"id":392094,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Erickson, H.","contributorId":41177,"corporation":false,"usgs":true,"family":"Erickson","given":"H.","email":"","affiliations":[],"preferred":false,"id":392090,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Wigington, P. Jr.","contributorId":18928,"corporation":false,"usgs":true,"family":"Wigington","given":"P.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":392087,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Lee, J.","contributorId":58596,"corporation":false,"usgs":true,"family":"Lee","given":"J.","affiliations":[],"preferred":false,"id":392092,"contributorType":{"id":1,"text":"Authors"},"rank":11}]}} ,{"id":70022129,"text":"70022129 - 1999 - Conditions for bubble elongation in cold ice-sheet ice","interactions":[],"lastModifiedDate":"2024-05-06T23:56:04.895529","indexId":"70022129","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2328,"text":"Journal of Glaciology","active":true,"publicationSubtype":{"id":10}},"title":"Conditions for bubble elongation in cold ice-sheet ice","docAbstract":"Highly elongated bubbles are sometimes observed in ice-sheet ice. Elongation is favored by rapid ice deformation, and opposed by diffusive processes. We use simple models to show that vapor transport dominates diffusion except possibly very close to the melting point, and that latent-heat effects are insignificant. Elongation is favored by larger bubbles at pore close-off, but is nearly independent of bubble compression below close-off. The simple presence of highly elongated bubbles indicates only that a critical ice-strain rate has been exceeded for significant time, and provides no information on possible disruption of stratigraphic continuity by ice deformation.
We examine possible sources of a small tsunami produced by the 1906 San Francisco earthquake, recorded at a single tide gauge station situated at the opening to San Francisco Bay. Coseismic vertical displacement fields were calculated using elastic dislocation theory for geodetically constrained horizontal slip along a variety of offshore fault geometries. Propagation of the ensuing tsunami was calculated using a shallow-water hydrodynamic model that takes into account the effects of bottom friction. The observed amplitude and negative pulse of the first arrival are shown to be inconsistent with small vertical displacements (∼4–6 cm) arising from pure horizontal slip along a continuous right bend in the San Andreas fault offshore. The primary source region of the tsunami was most likely a recently recognized 3 km right step in the San Andreas fault that is also the probable epicentral region for the 1906 earthquake. Tsunami models that include the 3 km right step with pure horizontal slip match the arrival time of the tsunami, but underestimate the amplitude of the negative first-arrival pulse. Both the amplitude and time of the first arrival are adequately matched by using a rupture geometry similar to that defined for the 1995 Mw (moment magnitude) 6.9 Kobe earthquake: i.e., fault segments dipping toward each other within the stepover region (83° dip, intersecting at 10 km depth) and a small component of slip in the dip direction (rake = −172°). Analysis of the tsunami provides confirming evidence that the 1906 San Francisco earthquake initiated at a right step in a right-lateral fault and propagated bilaterally, suggesting a rupture initiation mechanism similar to that for the 1995 Kobe earthquake.
The mode of deglaciation in the northwestern White Mountains of New Hampshire has been controversial since the mid 1800's. Early workers believed that active ice deposited the Bethlehem Moraine complex in the Ammonoosuc River basin during recession of the last ice sheet. In the 1930's this deglaciation model was replaced by the concept of widespread simultaneous stagnation and downwastage of Late Wisconsinan ice. The present authors reexamined the Bethlehem Moraine complex and support the original interpretation of a series of moraines deposited by active ice. We found other moraine clusters of similar age to the northeast in the Johns River and Israel River basins. Ice-marginal deposits that probably correlate with the Bethlehem Moraine also occur west of Littleton. The Bethlehem Moraine complex and equivalent deposits in adjacent areas were formed by readvance and oscillatory retreat of the Connecticut Valley lobe of the Laurentide Ice Sheet. This event is called the Littleton-Bethlehem Readvance. Throughout the study area, sequences of glaciolacustrine deposits and meltwater drainage channels indicate progressive northward recession of the glacier margin. Radiocarbon dates from nearby New England and Québec suggest that the ice sheet withdrew from this part of the White Mountains between about 12 500 and 12 000 14 C yr BP. We attribute the Littleton- Bethlehem Readvance to a brief climatic cooling during Older Dyas time, close to 12,000 BP.
","language":"English","publisher":"Les Presses de l'Université de Montréal","doi":"10.7202/004882ar","usgsCitation":"Thompson, W.B., Fowler, B.K., and Dorion, C.C., 1999, Deglaciation of the northwestern White Mountains, New Hampshire: Geographie Physique et Quaternaire, v. 53, no. 1, p. 59-77, https://doi.org/10.7202/004882ar.","productDescription":"19 p.","startPage":"59","endPage":"77","numberOfPages":"19","costCenters":[],"links":[{"id":479509,"rank":2,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://doi.org/10.7202/004882ar","text":"External Repository"},{"id":230887,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"New Hampshire","otherGeospatial":"White Mountains","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -71.03243018820368,\n 44.504681864058426\n ],\n [\n -72.05787655312217,\n 44.504681864058426\n ],\n [\n -72.05787655312217,\n 44.13794517845437\n ],\n [\n -71.03243018820368,\n 44.13794517845437\n ],\n [\n -71.03243018820368,\n 44.504681864058426\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"53","issue":"1","noUsgsAuthors":false,"publicationDate":"2002-10-02","publicationStatus":"PW","scienceBaseUri":"5059fe53e4b0c8380cd4ec8b","contributors":{"authors":[{"text":"Thompson, Woodrow B.","contributorId":67482,"corporation":false,"usgs":true,"family":"Thompson","given":"Woodrow","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":392098,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fowler, Brian K.","contributorId":83975,"corporation":false,"usgs":true,"family":"Fowler","given":"Brian","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":392096,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dorion, C. C.","contributorId":93236,"corporation":false,"usgs":true,"family":"Dorion","given":"C.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":392097,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021808,"text":"70021808 - 1999 - A record of estuarine water contamination from the Cd content of foraminiferal tests in San Francisco Bay, California","interactions":[],"lastModifiedDate":"2016-07-27T13:43:42","indexId":"70021808","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2662,"text":"Marine Chemistry","active":true,"publicationSubtype":{"id":10}},"title":"A record of estuarine water contamination from the Cd content of foraminiferal tests in San Francisco Bay, California","docAbstract":"A five-year dissolved Cd time series from San Francisco Bay and adjacent coastal water shows that the composition of surface water towards the mouth of the estuary is determined largely by the effect of coastal upwelling. Cd concentrations inside and outside the estuary (0.2-1.0 nmol/kg) increase as Cd-rich deep water is advected to the surface near the coast during spring and summer. On average, the mean Cd concentrations inside San Francisco Bay (0.54 nmol/kg) during 1991-1995 was significantly higher than outside (0.35 nmol/kg), however. Surface samples collected throughout San Francisco Bay confirm an internal Cd source unrelated to river discharge. The Cd content of the test of a benthic foraminifer (Elphidiella hannai) in a dated sediment core from San Francisco Bay was measured to determine if the water column Cd enrichments in San Francisco Bay could be related to the rapid development of the watershed. The method is based on the observation that the Cd/Ca ratio of carefully cleaned tests of foraminifera is, determined by the dissolved Cd content of overlying water at the time of test formation. Pre-industrial foraminiferal Cd/Ca ratios in the sediment core average 274 ?? 15 nmol/mol (n = 19) nmol/mol. Foraminiferal Cd/Ca ratios increased to 386 ?? 33 nmol/mol (n = 19) over the past several decades indicating a 40% increase in the mean Cd content of surface water in Central San Francisco Bay. We suggest that, in addition to Cd discharges into the estuary, indirect consequences of agricultural development in the Central Valley of California could have contributed to this increase. This new method to reconstruct estuarine contamination is not affected by some of the processes that complicate the interpretation of changes in bulk sediment metal concentrations.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Chemistry","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0304-4203(98)00084-X","issn":"03044203","usgsCitation":"VanGeen, A., and Luoma, S., 1999, A record of estuarine water contamination from the Cd content of foraminiferal tests in San Francisco Bay, California: Marine Chemistry, v. 64, no. 1-2, p. 57-69, https://doi.org/10.1016/S0304-4203(98)00084-X.","startPage":"57","endPage":"69","numberOfPages":"13","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":487407,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1016/s0304-4203(98)00084-x","text":"Publisher Index Page"},{"id":229562,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206371,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0304-4203(98)00084-X"}],"volume":"64","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e53ce4b0c8380cd46c0f","contributors":{"authors":[{"text":"VanGeen, A.","contributorId":84086,"corporation":false,"usgs":true,"family":"VanGeen","given":"A.","email":"","affiliations":[],"preferred":false,"id":391262,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Luoma, S. N.","contributorId":86353,"corporation":false,"usgs":true,"family":"Luoma","given":"S. N.","affiliations":[],"preferred":false,"id":391263,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022032,"text":"70022032 - 1999 - Copper, lead, mercury and zinc in periphyton from the south Florida ecosystem","interactions":[],"lastModifiedDate":"2018-12-21T06:33:15","indexId":"70022032","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3609,"text":"Toxicological and Environmental Chemistry","active":true,"publicationSubtype":{"id":10}},"title":"Copper, lead, mercury and zinc in periphyton from the south Florida ecosystem","docAbstract":"Periphyton samples from the Big Cypress National Preserve were analyzed for concentrations of copper, lead, zinc, mercury, and methylmercury. Concentrations of organic carbon, inorganic carbon, nitrogen, and phosphorus in periphyton samples also were determined. The samples were extracted with sodium acetate solution at a pH of 5.5 to determine exchangeable and carbonate phase metal concentrations in periphyton. Total metal concentrations in the periphyton were directly related to the degree of calcite saturation in the water column. Exchangeable and carbonate phase metal concentrations were directly related to the percent inorganic carbon in the samples. A connection between the geochemistry of trace metals and calcite precipitation and dissolution is suggested.","language":"English","publisher":"Taylor and Francis","doi":"10.1080/02772249909358754","issn":"02772248","usgsCitation":"Cox, T., Simon, N., and Newland, L., 1999, Copper, lead, mercury and zinc in periphyton from the south Florida ecosystem: Toxicological and Environmental Chemistry, v. 70, no. 3-4, p. 259-274, https://doi.org/10.1080/02772249909358754.","productDescription":"16 p.","startPage":"259","endPage":"274","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230319,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"70","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fc01e4b0c8380cd4e093","contributors":{"authors":[{"text":"Cox, T.","contributorId":42249,"corporation":false,"usgs":true,"family":"Cox","given":"T.","email":"","affiliations":[],"preferred":false,"id":392099,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Simon, N.S.","contributorId":103272,"corporation":false,"usgs":true,"family":"Simon","given":"N.S.","email":"","affiliations":[],"preferred":false,"id":392101,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Newland, L.","contributorId":96444,"corporation":false,"usgs":true,"family":"Newland","given":"L.","email":"","affiliations":[],"preferred":false,"id":392100,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021809,"text":"70021809 - 1999 - The search for a source rock for the giant Tar Sand triangle accumulation, southeastern Utah","interactions":[],"lastModifiedDate":"2023-01-23T16:49:21.418653","indexId":"70021809","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":701,"text":"American Association of Petroleum Geologists Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"The search for a source rock for the giant Tar Sand triangle accumulation, southeastern Utah","docAbstract":"A large proportion (about 36%) of the worlds oil resource is contained in accumulations of heavy oil or tar. In these large deposits of degraded oil, the oil in place represents only a fraction of what was present at the time of accumulation. In many of these deposits, the source of the oil is unknown, and the oil is thought to have migrated over long distances to the reservoirs. The Tar Sand triangle in southeastern Utah contains the largest tar sand accumulation in the United States, with 6.3 billion bbl of heavy oil estimated to be in place. The deposit is thought to have originally contained 13-16 billion bbl prior to the biodegradation, water washing, and erosion that have taken place since the middle-late Tertiary. The source of the oil is unknown.
The tar is primarily contained within the Lower Permian White Rim Sandstone, but extends into permeable parts of overlying and underlying beds. Oil is interpreted to have migrated into the White Rim sometime during the Tertiary when the formation was at a depth of approximately 3500 m. This conclusion is based on integration of fluid inclusion analysis, time-temperature reconstruction, and apatite fission-track modeling for the White Rim Sandstone. Homogenization temperatures cluster around 85-90°C for primary fluid inclusions in authigenic, nonferroan dolomite in the White Rim. The fluid inclusions are associated with fluorescent oil-bearing inclusions, indicating that dolomite precipitation was coeval with oil migration. Burial reconstruction suggests that the White Rim Sand stone reached its maximum burial depth from 60 to 24 Ma, and that maximum burial was followed by unroofing from 24 to 0 Ma. Time-temperature modeling indicates that the formation experienced temperatures of 85-90°C from about 35 to 40 Ma during maximum burial. Maximum formation temperatures of about 105-110°C were reached at about 24 Ma, just prior to unroofing.
Thermal modeling is used to examine the history of potential source rocks for the White Rim oil. The most attractive potential sources for White Rim oil include beds within one or more of the following formations: the Proterozoic Chuar Group, which is present in the subsurface southwest of the Tar Sand triangle; the Mississippian Delle Phosphatic Member of the Deseret Limestone and equivalent formations, the Permian Kaibab Limestone, the Sinbad Limestone Member of the Triassic Moenkopi Formation, and the Jurassic Arapien Shale, Twin Creek Limestone, and Carmel Formation, which are present west of the Tar Sand triangle; the Pennsylvanian Paradox Formation in the Paradox basin east of the Tar Sand triangle; and the Permian Park City Formation northwest of the Tar Sand triangle. Each formation has a high total organic carbon content and is distributed over a wide enough geographic area to have provided a huge volume of oil. Source beds in all of the formations reached thermal maturity at times prior to or during the time that migration into the White Rim is interpreted to have occurred. Based on all available data, the most likely source for the Tar Sand triangle appears to be the Mississippian Delle Phosphatic Member of the Deseret Limestone. Secondary migration out of the Delle is interpreted to have occurred during the Cretaceous, during Sevier thrusting. Subsequent tertiary migration into the Tar Sand triangle reservoir is interpreted to have occurred later, during middle Tertiary Laramide deformation.
","language":"English","publisher":"American Association of Petroleum Geologists","publisherLocation":"Tulsa, OK","doi":"10.1306/00AA9BD8-1730-11D7-8645000102C1865D","usgsCitation":"Huntoon, J.E., Hansley, P., and Naeser, N.D., 1999, The search for a source rock for the giant Tar Sand triangle accumulation, southeastern Utah: American Association of Petroleum Geologists Bulletin, v. 83, no. 3, p. 467-495, https://doi.org/10.1306/00AA9BD8-1730-11D7-8645000102C1865D.","productDescription":"29 p.","startPage":"467","endPage":"495","numberOfPages":"29","costCenters":[],"links":[{"id":229563,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Utah","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -110.40307140277676,\n 38.245591077835826\n ],\n [\n -110.40307140277676,\n 37.840235115054426\n ],\n [\n -109.91648969374877,\n 37.840235115054426\n ],\n [\n -109.91648969374877,\n 38.245591077835826\n ],\n [\n -110.40307140277676,\n 38.245591077835826\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"83","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bafbfe4b08c986b324a00","contributors":{"authors":[{"text":"Huntoon, J. E.","contributorId":98060,"corporation":false,"usgs":true,"family":"Huntoon","given":"J.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":391266,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hansley, P. L.","contributorId":82299,"corporation":false,"usgs":true,"family":"Hansley","given":"P. L.","affiliations":[],"preferred":false,"id":391265,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Naeser, N. D.","contributorId":74510,"corporation":false,"usgs":true,"family":"Naeser","given":"N.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":391264,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022033,"text":"70022033 - 1999 - Greigite (Fe3S4) as an indicator of drought - The 1912-1994 sediment magnetic record from White Rock Lake, Dallas, Texas, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:19:51","indexId":"70022033","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2411,"text":"Journal of Paleolimnology","active":true,"publicationSubtype":{"id":10}},"title":"Greigite (Fe3S4) as an indicator of drought - The 1912-1994 sediment magnetic record from White Rock Lake, Dallas, Texas, USA","docAbstract":"Combined magnetic and geochemical studies were conducted on sediments from White Rock Lake, a reservoir in suburban Dallas (USA), to investigate how land use has affected sediment and water quality since the reservoir was filled in 1912. The chronology of a 167-cm-long core is constrained by the recognition of the pre-reservoir surface and by 137Cs results. In the reservoir sediments, magnetic susceptibility (MS) and isothermal remanent magnetization (IRM) are largely carried by detrital titanomagnetite that originally formed in igneous rocks. Titanomagnetite and associated hematite are the dominant iron oxides in a sample from the surficial deposit in the watershed but are absent in the underlying Austin Chalk. Therefore, these minerals were transported by wind into the watershed. After about 1960, systematic decreases in Ti, Fe, and Al suggest diminished input of detrital Fe-Ti oxides from the surficial deposits. MS and IRM remain constant over this interval, however, implying compensation by an increase in strongly magnetic material derived from human activity. Anthropogenic magnetite in rust and ferrite spherules (from fly ash?) are more common in sediment deposited after about 1970 than before and may account for the constant magnetization despite the implied decrease in detrital Fe-Ti oxides. An unexpected finding is the presence of authigenic greigite (Fe3S4), the abundance of which is at least partly controlled by climate. Greigite is common in sediments that predate about 1975, with zones of concentration indicated by relatively high IRM/MS. High greigite contents in sediment deposited during the early to mid-1950s and during the mid-1930s correspond to several-year periods of below-average precipitation and drought from historical records. Relatively long water-residence times in the reservoir during these periods may have led to elevated levels of sulfate available for bacterial sulfate reduction. The sulfate was probably derived via the oxidation of pyrite that is common in the underlying Austin Chalk. These results provide a basis for the paleoenvironmental interpretation of greigite occurrence in older lake sediments. The results also indicate that greigite formed rapidly and imply that it can be preserved in the amounts produced over a short time span (in this lake, only a few years). This finding thus suggests that, in some lacustrine settings, greigite is capable of recording paleomagnetic secular variation.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Paleolimnology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1023/A:1008027815203","issn":"09212728","usgsCitation":"Reynolds, R.L., Rosenbaum, J.G., Van Metre, P., Tuttle, M., Callender, E., and Goldin, A., 1999, Greigite (Fe3S4) as an indicator of drought - The 1912-1994 sediment magnetic record from White Rock Lake, Dallas, Texas, USA: Journal of Paleolimnology, v. 21, no. 2, p. 193-206, https://doi.org/10.1023/A:1008027815203.","startPage":"193","endPage":"206","numberOfPages":"14","costCenters":[],"links":[{"id":206587,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1008027815203"},{"id":230320,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"21","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2a6de4b0c8380cd5b186","contributors":{"authors":[{"text":"Reynolds, R. L. 0000-0002-4572-2942","orcid":"https://orcid.org/0000-0002-4572-2942","contributorId":79885,"corporation":false,"usgs":true,"family":"Reynolds","given":"R.","middleInitial":"L.","affiliations":[{"id":318,"text":"Geosciences and Environmental Change Science Center","active":true,"usgs":true}],"preferred":true,"id":392106,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rosenbaum, J. G.","contributorId":96685,"corporation":false,"usgs":true,"family":"Rosenbaum","given":"J.","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":392107,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Van Metre, P.","contributorId":31142,"corporation":false,"usgs":true,"family":"Van Metre","given":"P.","affiliations":[],"preferred":false,"id":392104,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Tuttle, M.","contributorId":26397,"corporation":false,"usgs":true,"family":"Tuttle","given":"M.","affiliations":[],"preferred":false,"id":392103,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Callender, E.","contributorId":72528,"corporation":false,"usgs":true,"family":"Callender","given":"E.","email":"","affiliations":[],"preferred":false,"id":392105,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Goldin, A.","contributorId":24950,"corporation":false,"usgs":true,"family":"Goldin","given":"A.","email":"","affiliations":[],"preferred":false,"id":392102,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70021910,"text":"70021910 - 1999 - Groundwater formation of martian valleys","interactions":[],"lastModifiedDate":"2012-03-12T17:19:39","indexId":"70021910","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2840,"text":"Nature","active":true,"publicationSubtype":{"id":10}},"title":"Groundwater formation of martian valleys","docAbstract":"The martian surface shows large outflow channels, widely accepted as having been formed by gigantic floods that could have occurred under climatic conditions like those seen today. Also present are branching valley networks that commonly have tributaries. These valleys are much smaller than the outflow channels and their origins and ages have been controversial. For example, they might have formed through slow erosion by water running across the surface, either early or late in Mars' history, possibly protected from harsh conditions by ice cover. Alternatively, they might have formed through groundwater or ground-ice processes that undermine the surface and cause collapse, again either early or late in Mars' history. Long-duration surface runoff would imply climatic conditions quite different from the present environment. Here we present high-resolution images of martian valleys that support the view that ground water played an important role in their formation, although we are unable as yet to establish when this occurred.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Nature","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1038/17551","issn":"00280836","usgsCitation":"Malin, M.C., and Carr, M.H., 1999, Groundwater formation of martian valleys: Nature, v. 397, no. 6720, p. 589-591, https://doi.org/10.1038/17551.","startPage":"589","endPage":"591","numberOfPages":"3","costCenters":[],"links":[{"id":206290,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1038/17551"},{"id":229313,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"397","issue":"6720","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2da4e4b0c8380cd5bf7c","contributors":{"authors":[{"text":"Malin, M. C.","contributorId":68830,"corporation":false,"usgs":false,"family":"Malin","given":"M.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":391650,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Carr, M. H.","contributorId":84727,"corporation":false,"usgs":true,"family":"Carr","given":"M.","email":"","middleInitial":"H.","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":false,"id":391651,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70021909,"text":"70021909 - 1999 - Evidence for recent volcanism on mars from crater counts","interactions":[],"lastModifiedDate":"2012-03-12T17:19:38","indexId":"70021909","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2840,"text":"Nature","active":true,"publicationSubtype":{"id":10}},"title":"Evidence for recent volcanism on mars from crater counts","docAbstract":"Impact craters help characterize the age of a planetary surface, because they accumulate with time. They also provide useful constraints on the importance of surface erosion, as such processes will preferentially remove the smaller craters. Earlier studies of martian crater populations revealed that erosion and dust deposition are important processes on Mars. They disagreed, however, on the age of the youngest volcanism. These earlier studies were limited by image resolution to craters larger than a few hundred metres in diameter. Here we report an analysis, using new images obtained by the Mars Global Surveyor spacecraft, of crater populations that extend the size distribution down to about 16 m. Our results indicate a wide range of surface ages, with one region-lava flows within the Arsia Mons calderathat we estimate to be no older than 40-100 million years. We suggest that volcanism is a continuing process on Mars.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Nature","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1038/17545","issn":"00280836","usgsCitation":"Hartmann, W., Malin, M., McEwen, A., Carr, M., Soderblom, L., Thomas, P., Danielson, E., James, P., and Veverka, J., 1999, Evidence for recent volcanism on mars from crater counts: Nature, v. 397, no. 6720, p. 586-589, https://doi.org/10.1038/17545.","startPage":"586","endPage":"589","numberOfPages":"4","costCenters":[],"links":[{"id":206289,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1038/17545"},{"id":229312,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"397","issue":"6720","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0d50e4b0c8380cd52f45","contributors":{"authors":[{"text":"Hartmann, W.K.","contributorId":96002,"corporation":false,"usgs":true,"family":"Hartmann","given":"W.K.","email":"","affiliations":[],"preferred":false,"id":391646,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Malin, M.","contributorId":8636,"corporation":false,"usgs":true,"family":"Malin","given":"M.","affiliations":[],"preferred":false,"id":391641,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"McEwen, A.","contributorId":39105,"corporation":false,"usgs":true,"family":"McEwen","given":"A.","affiliations":[],"preferred":false,"id":391642,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Carr, M.","contributorId":105845,"corporation":false,"usgs":true,"family":"Carr","given":"M.","affiliations":[],"preferred":false,"id":391648,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Soderblom, L.","contributorId":106244,"corporation":false,"usgs":true,"family":"Soderblom","given":"L.","affiliations":[],"preferred":false,"id":391649,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Thomas, P.","contributorId":59185,"corporation":false,"usgs":true,"family":"Thomas","given":"P.","affiliations":[],"preferred":false,"id":391644,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Danielson, E.","contributorId":102341,"corporation":false,"usgs":true,"family":"Danielson","given":"E.","email":"","affiliations":[],"preferred":false,"id":391647,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"James, P.","contributorId":47888,"corporation":false,"usgs":true,"family":"James","given":"P.","email":"","affiliations":[],"preferred":false,"id":391643,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Veverka, J.","contributorId":71689,"corporation":false,"usgs":true,"family":"Veverka","given":"J.","email":"","affiliations":[],"preferred":false,"id":391645,"contributorType":{"id":1,"text":"Authors"},"rank":9}]}} ,{"id":70021810,"text":"70021810 - 1999 - Influence of the Atlantic inflow and Mediterranean outflow currents on late Quaternary sedimentary facies of the Gulf of Cadiz continental margin","interactions":[],"lastModifiedDate":"2012-03-12T17:19:41","indexId":"70021810","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2667,"text":"Marine Geology","active":true,"publicationSubtype":{"id":10}},"title":"Influence of the Atlantic inflow and Mediterranean outflow currents on late Quaternary sedimentary facies of the Gulf of Cadiz continental margin","docAbstract":"The late Quaternary pattern of sedimentary facies on the Spanish Gulf of Cadiz continental shelf results from an interaction between a number of controlling factors that are dominated by the Atlantic inflow currents flowing southeastward across the Cadiz shelf toward the Strait of Gibraltar. An inner shelf shoreface sand facies formed by shoaling waves is modified by the inflow currents to form a belt of sand dunes at 10-20 m that extends deeper and obliquely down paleo-valleys as a result of southward down-valley flow. A mid-shelf Holocene mud facies progrades offshore from river mouth sources, but Atlantic inflow currents cause extensive progradation along shelf toward the southeast. Increased inflow current speeds near the Strait of Gibraltar and the strong Mediterranean outflow currents there result in lack of mud deposition and development of a reworked transgressive sand dune facies across the entire southernmost shelf. At the outer shelf edge and underlying the mid-shelf mud and inner shelf sand facies is a late Pleistocene to Holocene transgressive sand sheet formed by the eustatic shoreline advance. The late Quaternary pattern of contourite deposits on the Spanish Gulf of Cadiz continental slope results from an interaction between linear diapiric ridges that are oblique to slope contours and the Mediterranean outflow current flowing northwestward parallel to the slope contours and down valleys between the ridges. Coincident with the northwestward decrease in outflow current speeds from the Strait there is the following northwestward gradation of contourite sediment facies: (1) upper slope sand to silt bed facies, (2) sand dune facies on the upstream mid-slope terrace, (3) large mud wave facies on the lower slope, (4) sediment drift facies banked against the diapiric ridges, and (5) valley facies between the ridges. The southeastern sediment drift facies closest to Gibraltar contains medium-fine sand beds interbedded with mud. The adjacent valley floor facies is composed of gravelly, shelly coarse to medium sand lags and large sand dunes on the valley margins. By comparison, the northwestern drift contains coarse silt interbeds and the adjacent valley floors exhibit small to medium sand dunes of fine sand. Because of the complex pattern of contour-parallel and valley-perpendicular flow paths of the Mediterranean outflow current, the larger-scale bedforms and coarser-grained sediment of valley facies trend perpendicular to the smaller-scale bedforms and finer-grained contourite deposits of adjacent sediment drift facies. Radiocarbon ages verify that the inner shelf shoreface sand facies (sedimentation rate 7.1 cm/kyr), mid-shelf mud facies (maximum rate 234 cm/kyr) and surface sandy contourite layer of 0.2-1.2 m thickness on the Cadiz slope (1-12 cm/kyr) have deposited during Holocene time when high sea level results in maximum water depth over the Gibraltar sill and full development of the Atlantic inflow and Mediterranean outflow currents. The transgressive sand sheet of the shelf, and the mud layer underlying the surface contourite sand sheet of the slope, correlate, respectively, with the late Pleistocene sea level lowstand and apparent weak Mediterranean outflow current.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0025-3227(98)00143-1","issn":"00253227","usgsCitation":"Nelson, C., Baraza, J., Maldonado, A., Rodero, J., Escutia, C., and Barber, J.H., 1999, Influence of the Atlantic inflow and Mediterranean outflow currents on late Quaternary sedimentary facies of the Gulf of Cadiz continental margin: Marine Geology, v. 155, no. 1-2, p. 99-129, https://doi.org/10.1016/S0025-3227(98)00143-1.","startPage":"99","endPage":"129","numberOfPages":"31","costCenters":[],"links":[{"id":206381,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0025-3227(98)00143-1"},{"id":229596,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"155","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3b85e4b0c8380cd625ef","contributors":{"authors":[{"text":"Nelson, C.H.","contributorId":88346,"corporation":false,"usgs":true,"family":"Nelson","given":"C.H.","email":"","affiliations":[],"preferred":false,"id":391270,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Baraza, J.","contributorId":12200,"corporation":false,"usgs":true,"family":"Baraza","given":"J.","email":"","affiliations":[],"preferred":false,"id":391267,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Maldonado, A.","contributorId":90437,"corporation":false,"usgs":true,"family":"Maldonado","given":"A.","affiliations":[],"preferred":false,"id":391272,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Rodero, J.","contributorId":64417,"corporation":false,"usgs":true,"family":"Rodero","given":"J.","email":"","affiliations":[],"preferred":false,"id":391268,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Escutia, C.","contributorId":88514,"corporation":false,"usgs":true,"family":"Escutia","given":"C.","affiliations":[],"preferred":false,"id":391271,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Barber, J. H. Jr.","contributorId":82275,"corporation":false,"usgs":true,"family":"Barber","given":"J.","suffix":"Jr.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":391269,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70021811,"text":"70021811 - 1999 - Temporal and spatial variability of the sediment grain-size distribution on the Eel shelf: The flood layer of 1995","interactions":[],"lastModifiedDate":"2012-03-12T17:19:41","indexId":"70021811","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2667,"text":"Marine Geology","active":true,"publicationSubtype":{"id":10}},"title":"Temporal and spatial variability of the sediment grain-size distribution on the Eel shelf: The flood layer of 1995","docAbstract":"Sediment grain-size characteristics observed on the Eel shelf have been analyzed using a wet-sieving technique that minimizes breakage of aggregates. At several sites on the 70-m isobath north of the river, where a 1995 flood layer attained a maximum thickness of about 9 cm, replicate box cores were collected on seven cruises during February 1995 to January 1997. These samples provide a unique opportunity to follow the evolution of a flood layer over a two-year period as it was modified and gradually buried. One month after the flood, a layer of tan-colored, high-porosity sediment with up to 96% of its particles in the size range of 0-20 ??m had accumulated on the central part of the shelf, 7-30 km north of the river and principally between the 50-m and 90-m isobaths. Substantial coarsening of this layer occurred between February 1995 and May 1995, particularly along the southern and the landward edge of the deposit in water depths of <70 m. The early stage of coarsening was probably caused by physical reworking of the surface 0.5-cm of the deposit and by addition of new sediment from shallower regions of the shelf. Temporal changes in inventories of several grain-size fractions show that physical processes continued to add coarse sediment to the flood layer after May 1995, but the large increases in thickness of the surface mixed layer could only be attributed to bioturbation by a recovering, or seasonally fluctuating, benthic community. The 1995 flood layer has evolved from exhibiting limited variability and normal grading (i:e., upward fining) to a layer that (1) shows significant spatial variability on scales from centimeters to 10's of meters, (2) is substantially coarser owing to additions of sediment from the inner shelf, (3) is inversely graded (i.e., coarsens upward), and (4) is intensely bioturbated to depths of 4-5 cm.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0025-3227(98)00111-X","issn":"00253227","usgsCitation":"Drake, D., 1999, Temporal and spatial variability of the sediment grain-size distribution on the Eel shelf: The flood layer of 1995: Marine Geology, v. 154, no. 1-4, p. 169-182, https://doi.org/10.1016/S0025-3227(98)00111-X.","startPage":"169","endPage":"182","numberOfPages":"14","costCenters":[],"links":[{"id":206382,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0025-3227(98)00111-X"},{"id":229597,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"154","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba4f6e4b08c986b3206df","contributors":{"authors":[{"text":"Drake, D.E.","contributorId":48150,"corporation":false,"usgs":true,"family":"Drake","given":"D.E.","email":"","affiliations":[],"preferred":false,"id":391273,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70022106,"text":"70022106 - 1999 - Wild turkey poult survival in southcentral Iowa","interactions":[],"lastModifiedDate":"2012-03-12T17:19:52","indexId":"70022106","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2508,"text":"Journal of Wildlife Management","active":true,"publicationSubtype":{"id":10}},"title":"Wild turkey poult survival in southcentral Iowa","docAbstract":"Poult survival is key to understanding annual change in wild turkey (Meleagris gallopavo) populations. Survival of eastern wild turkey poults (M. g. silvestris) 0-4 weeks posthatch was studied in southcentral Iowa during 1994-97. Survival estimates of poults were calculated based on biweekly flush counts and daily locations acquired via radiotelemetry. Poult survival averaged 0.52 ?? 0.14% (?? ?? SE) for telemetry counts and 0.40 ?? 0.15 for flush counts. No within-year or across-year differences were detected between estimation techniques. More than 72% (n = 32) of documented poult mortality occurred ???14 days posthatch, and mammalian predation accounted for 92.9% of documented mortality. If mortality agents are not of concern, we suggest biologists conduct 4-week flush counts to obtain poult survival estimates for use in population models and development of harvest recommendations.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Wildlife Management","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"0022541X","usgsCitation":"Hubbard, M.W., Garner, D., and Klaas, E., 1999, Wild turkey poult survival in southcentral Iowa: Journal of Wildlife Management, v. 63, no. 1, p. 199-203.","startPage":"199","endPage":"203","numberOfPages":"5","costCenters":[],"links":[{"id":230281,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"63","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bd0c3e4b08c986b32f050","contributors":{"authors":[{"text":"Hubbard, Michael W.","contributorId":67236,"corporation":false,"usgs":true,"family":"Hubbard","given":"Michael","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":392385,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Garner, D.L.","contributorId":105823,"corporation":false,"usgs":true,"family":"Garner","given":"D.L.","email":"","affiliations":[],"preferred":false,"id":392386,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Klaas, Erwin E.","contributorId":21487,"corporation":false,"usgs":true,"family":"Klaas","given":"Erwin E.","affiliations":[],"preferred":false,"id":392384,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021908,"text":"70021908 - 1999 - Reconstructing late Quaternary deep-water masses in the eastern Arctic Ocean using benthonic Ostracoda","interactions":[],"lastModifiedDate":"2012-03-12T17:19:38","indexId":"70021908","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Reconstructing late Quaternary deep-water masses in the eastern Arctic Ocean using benthonic Ostracoda","docAbstract":"The distribution of Ostracoda in three long cores from the deep eastern Arctic Ocean was studied to determine the palaeoceanographical history of the Eurasian Basin during the late Quaternary. The samples for this study were obtained from the Lomonosov Ridge, Morris Jesup Rise and Yermak Plateau during the Arctic 91 expedition. Ostracoda previously studied in coretops at the same sites as the present study have shown that individual species have a strong association with different water masses and bathymetry. Throughout the late Quaternary, cores exhibit ostracod-rich layers separated by barren intervals. On the basis of biostratigraphical, isotopic and palaeomagnetic data the fossiliferous levels are interpreted as representing interglacial stages. The twenty most significant species were selected for subsequent quantitative investigation using Cluster and Factor analyses, in order to determine similarity and variance between the assemblages. An additional statistical method employing Modern Analogues and the Squared Chord Distance dissimilarity coefficient was utilized to compare the present late Quaternary fossil samples with a modern Arctic database. The results reveal a major faunal division within the Arctic Ocean Deep Water (AODW). Highly abundant and diverse assemblages within the cores were found to group and have good analogues with the Recent bathyal depth (1000-2500 m) upper AODW assemblages. Conversely, assemblages with low abundance and diversity correlate well with abyssal depth (> 3000 m) lower AODW assemblages. The palaeoceanographical history is complicated by the influence of adjacent water masses such as Canada Basin Deep Water (CBDW), Greenland Sea Deep Water (GSDW) and most importantly, Arctic Intermediate Water (AIW), which all had an influence on the ostracod assemblages during the late Quaternary. An enhanced flow of warm saline AIW into the Eurasian Basin results in species-rich upper AODW assemblages having good analogues down to 2750 m in the water column. In contrast, lower AODW assemblages influenced by cold well-oxygenated GSDW give analogues at depths as shallow as 1000 m. The faunal changes are the consequence of rapid climatic fluctuations in the eastern Arctic Ocean during the late Quaternary that are intrinsically linked to palaeoceanographical alternations in warm and cold current inflow from adjacent basins.","largerWorkTitle":"Marine Micropaleontology","language":"English","doi":"10.1016/S0377-8398(99)00022-5","issn":"03778398","usgsCitation":"Jones, R.L., Whatley, R., Cronin, T.M., and Dowsett, H., 1999, Reconstructing late Quaternary deep-water masses in the eastern Arctic Ocean using benthonic Ostracoda, in Marine Micropaleontology, v. 37, no. 3-4, p. 251-272, https://doi.org/10.1016/S0377-8398(99)00022-5.","startPage":"251","endPage":"272","numberOfPages":"22","costCenters":[],"links":[{"id":206288,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0377-8398(99)00022-5"},{"id":229311,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"37","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"50e4a250e4b0e8fec6cdb573","contributors":{"authors":[{"text":"Jones, R. Ll","contributorId":50678,"corporation":false,"usgs":true,"family":"Jones","given":"R.","email":"","middleInitial":"Ll","affiliations":[],"preferred":false,"id":391638,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Whatley, R.C.","contributorId":85211,"corporation":false,"usgs":true,"family":"Whatley","given":"R.C.","affiliations":[],"preferred":false,"id":391639,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Cronin, T. M. 0000-0002-2643-0979","orcid":"https://orcid.org/0000-0002-2643-0979","contributorId":42613,"corporation":false,"usgs":true,"family":"Cronin","given":"T.","email":"","middleInitial":"M.","affiliations":[{"id":40020,"text":"Florence Bascom Geoscience Center","active":true,"usgs":true}],"preferred":false,"id":391637,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Dowsett, H.J. 0000-0003-1983-7524","orcid":"https://orcid.org/0000-0003-1983-7524","contributorId":87924,"corporation":false,"usgs":true,"family":"Dowsett","given":"H.J.","affiliations":[],"preferred":false,"id":391640,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70022105,"text":"70022105 - 1999 - Practical Scheffe‐type credibility intervals for variables of a groundwater model","interactions":[],"lastModifiedDate":"2018-03-20T14:57:07","indexId":"70022105","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"displayTitle":"Practical Scheffé‐type credibility intervals for variables of a groundwater model","title":"Practical Scheffe‐type credibility intervals for variables of a groundwater model","docAbstract":"Simultaneous Scheffé‐type credibility intervals (the Bayesian version of confidence intervals) for variables of a groundwater flow model calibrated using a Bayesian maximum a posteriori procedure were derived by Cooley [1993b]. It was assumed that variances reflecting the expected differences between observed and model‐computed quantities used to calibrate the model are known, whereas they would often be unknown for an actual model. In this study the variances are regarded as unknown, and variance variability from observation to observation is approximated by grouping the data so that each group is characterized by a uniform variance. The credibility intervals are calculated from the posterior distribution, which was developed by considering each group variance to be a random variable about which nothing is known a priori, then eliminating it by integration. Numerical experiments using two test problems illustrate some characteristics of the credibility intervals. Nonlinearity of the statistical model greatly affected some of the credibility intervals, indicating that credibility intervals computed using the standard linear model approximation may often be inadequate to characterize uncertainty for actual field problems. The parameter characterizing the probability level for the credibility intervals was, however, accurately computed using a linear model approximation, as compared with values calculated using second‐order and fully nonlinear formulations. This allows the credibility intervals to be computed very efficiently.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/98WR02819","usgsCitation":"Cooley, R.L., 1999, Practical Scheffe‐type credibility intervals for variables of a groundwater model: Water Resources Research, v. 35, no. 1, p. 113-126, https://doi.org/10.1029/98WR02819.","productDescription":"14 p.","startPage":"113","endPage":"126","costCenters":[],"links":[{"id":479636,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/98wr02819","text":"Publisher Index Page"},{"id":230854,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"35","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a80a7e4b0c8380cd7b118","contributors":{"authors":[{"text":"Cooley, Richard L.","contributorId":8831,"corporation":false,"usgs":true,"family":"Cooley","given":"Richard","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":392383,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70021813,"text":"70021813 - 1999 - Late Holocene stratigraphy of the Tetimpa archaeological sites, northeast flank of Popocatepetl volcano, central Mexico","interactions":[],"lastModifiedDate":"2023-12-20T00:36:14.470811","indexId":"70021813","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","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":"Late Holocene stratigraphy of the Tetimpa archaeological sites, northeast flank of Popocatepetl volcano, central Mexico","docAbstract":"Late Holocene (<2500 yr B.P.) tephras bury a sequence of pre-Hispanic archaeological sites in the Tetimpa area, on the northeast flank of Popocatépetl volcano. From measured stratigraphic sections, 14C dates, and isopach maps, this paper reconstructs the eruptive chronology and the regional extent of deposits associated with the Tetimpa archaeological sites.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1999)111<0204:LHSOTT>2.3.CO;2","issn":"00167606","usgsCitation":"Panfil, M., Gardner, T., and Hirth, K., 1999, Late Holocene stratigraphy of the Tetimpa archaeological sites, northeast flank of Popocatepetl volcano, central Mexico: Geological Society of America Bulletin, v. 111, no. 2, p. 204-218, https://doi.org/10.1130/0016-7606(1999)111<0204:LHSOTT>2.3.CO;2.","productDescription":"15 p.","startPage":"204","endPage":"218","numberOfPages":"15","costCenters":[],"links":[{"id":229084,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"111","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a44ebe4b0c8380cd66ecd","contributors":{"authors":[{"text":"Panfil, M.S.","contributorId":10182,"corporation":false,"usgs":true,"family":"Panfil","given":"M.S.","email":"","affiliations":[],"preferred":false,"id":391278,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gardner, T.W.","contributorId":34675,"corporation":false,"usgs":true,"family":"Gardner","given":"T.W.","email":"","affiliations":[],"preferred":false,"id":391279,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hirth, K.G.","contributorId":49130,"corporation":false,"usgs":true,"family":"Hirth","given":"K.G.","email":"","affiliations":[],"preferred":false,"id":391280,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022104,"text":"70022104 - 1999 - Photogrammetric analysis of horizon panoramas: The Pathfinder landing site in Viking orbiter images","interactions":[],"lastModifiedDate":"2024-07-31T15:32:08.998976","indexId":"70022104","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2317,"text":"Journal of Geophysical Research E: Planets","active":true,"publicationSubtype":{"id":10}},"title":"Photogrammetric analysis of horizon panoramas: The Pathfinder landing site in Viking orbiter images","docAbstract":"Tiepoint measurements, block adjustment techniques, and sunrise/sunset pictures were used to obtain precise pointing data with respect to north for a set of 33 IMP horizon images. Azimuth angles for five prominent topographic features seen at the horizon were measured and correlated with locations of these features in Viking orbiter images. Based on this analysis, the Pathfinder line/sample coordinates in two raw Viking images were determined with approximate errors of 1 pixel, or 40 m. Identification of the Pathfinder location in orbit imagery yields geological context for surface studies of the landing site. Furthermore, the precise determination of coordinates in images together with the known planet-fixed coordinates of the lander make the Pathfinder landing site the most important anchor point in current control point networks of Mars.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/98JE01429","issn":"01480227","usgsCitation":"Oberst, J., Jaumann, R., Zeitler, W., Hauber, E., Kuschel, M., Parker, T., Golombek, M., Malin, M., and Soderblom, L., 1999, Photogrammetric analysis of horizon panoramas: The Pathfinder landing site in Viking orbiter images: Journal of Geophysical Research E: Planets, v. 104, no. E4, p. 8927-8933, https://doi.org/10.1029/98JE01429.","productDescription":"7 p.","startPage":"8927","endPage":"8933","numberOfPages":"7","costCenters":[],"links":[{"id":479629,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/98je01429","text":"Publisher Index Page"},{"id":230853,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Mars","volume":"104","issue":"E4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7a19e4b0c8380cd78d1b","contributors":{"authors":[{"text":"Oberst, J.","contributorId":103427,"corporation":false,"usgs":true,"family":"Oberst","given":"J.","email":"","affiliations":[],"preferred":false,"id":392381,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jaumann, R.","contributorId":81232,"corporation":false,"usgs":false,"family":"Jaumann","given":"R.","email":"","affiliations":[],"preferred":false,"id":392378,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Zeitler, W.","contributorId":6218,"corporation":false,"usgs":true,"family":"Zeitler","given":"W.","email":"","affiliations":[],"preferred":false,"id":392374,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hauber, E.","contributorId":81659,"corporation":false,"usgs":true,"family":"Hauber","given":"E.","affiliations":[],"preferred":false,"id":392379,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Kuschel, M.","contributorId":26105,"corporation":false,"usgs":true,"family":"Kuschel","given":"M.","email":"","affiliations":[],"preferred":false,"id":392376,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Parker, T.","contributorId":90901,"corporation":false,"usgs":true,"family":"Parker","given":"T.","affiliations":[],"preferred":false,"id":392380,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Golombek, M.","contributorId":72506,"corporation":false,"usgs":true,"family":"Golombek","given":"M.","affiliations":[],"preferred":false,"id":392377,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Malin, M.","contributorId":8636,"corporation":false,"usgs":true,"family":"Malin","given":"M.","affiliations":[],"preferred":false,"id":392375,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Soderblom, L.","contributorId":106244,"corporation":false,"usgs":true,"family":"Soderblom","given":"L.","affiliations":[],"preferred":false,"id":392382,"contributorType":{"id":1,"text":"Authors"},"rank":9}]}} ,{"id":70021814,"text":"70021814 - 1999 - Basin waves on a seafloor recording of the 1990 Upland, California, earthquake: Implications for ground motions from a larger earthquake","interactions":[],"lastModifiedDate":"2023-10-18T00:44:57.939754","indexId":"70021814","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1135,"text":"Bulletin of the Seismological Society of America","onlineIssn":"1943-3573","printIssn":"0037-1106","active":true,"publicationSubtype":{"id":10}},"title":"Basin waves on a seafloor recording of the 1990 Upland, California, earthquake: Implications for ground motions from a larger earthquake","docAbstract":"The velocity and displacement time series from a recording on the seafloor at 74 km from the 1990 Upland earthquake (M = 5.6) are dominated by late-arriving waves with periods of 6 to 7 sec. These waves are probably surface waves traveling across the Los Angeles basin. Response spectra for the recording are in agreement with predictions from empirical regression equations and theoretical models for periods less than about 1 sec but are significantly larger than those predictions for longer periods. The longer-period spectral amplitudes are controlled by the late-arriving waves, which are not included in the theoretical models and are underrepresented in the data used in the empirical analyses. When the motions are scaled to larger magnitude, the results are in general agreement with simulations of wave propagation in the Los Angeles basin by Graves (1998).