{"pageNumber":"3244","pageRowStart":"81075","pageSize":"25","recordCount":184904,"records":[{"id":70022417,"text":"70022417 - 2000 - Morphology and processes in Lake Tahoe (California-Nevada)","interactions":[],"lastModifiedDate":"2022-09-22T16:15:03.225428","indexId":"70022417","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","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":"Morphology and processes in Lake Tahoe (California-Nevada)","docAbstract":"Lake Tahoe was surveyed using a state-of-the-art, high-resolution, multibeam mapping system to provide an accurate base map for the myriad of ongoing environmental studies in and around the lake. The newly defined basin morphology shows steep basin margins on the northern, eastern, and western sides and a gentle margin on the southern side. Two large, flat plateaus several kilometers wide extend from the shore to about 40 m water depth in the northwestern sections of the basin. A series of ridges in the west and north are presumed traces of faults, some of which border the lake basin and some of which traverse across the northern section of the lake and converge in McKinney Bay. McKinney Bay is a large reentrant in the western margin that was created by a failure of the western margin that occurred about 300 ka. The failure generated a major debris avalanche that carried large blocks, some more than 1000 m long and 80 m high, accross the basin. Apparently, the debris avalanche was deflected by the eastern margin of the basin and flowed to the north and south. Small debris flows and slides have continued to occur in this area. Small debris aprons along the northern, western, and eastern margins, some apparently the remnants of collapsed terminal moraines formed in the basin from the 160 ka Tahoe Glaciation, which reached the edge of the basin. Eroded plateaus and ridges occur on a glacial outwash plain that covers the gentle southern margin. The plateaus and ridges are inferred to be remnants of another large terminal moraine of the Tahoe Glaciation.","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(2000)112<736:MAPILT>2.0.CO;2","issn":"00167606","usgsCitation":"Gardner, J., Mayer, L.A., and Hughs, C.J., 2000, Morphology and processes in Lake Tahoe (California-Nevada): Geological Society of America Bulletin, v. 112, no. 5, p. 736-746, https://doi.org/10.1130/0016-7606(2000)112<736:MAPILT>2.0.CO;2.","productDescription":"11 p.","startPage":"736","endPage":"746","costCenters":[],"links":[{"id":230833,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California, Nevada","otherGeospatial":"Lake Tahoe","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -119.99885559082031,\n              38.92522904714054\n            ],\n            [\n              -119.99198913574217,\n              38.9396506365778\n            ],\n            [\n              -119.98100280761719,\n              38.94125285438687\n            ],\n            [\n              -119.95559692382812,\n              38.94819537985111\n            ],\n            [\n              -119.94323730468749,\n              38.962078391086926\n            ],\n            [\n              -119.93637084960938,\n              38.965815660189016\n            ],\n            [\n              -119.94735717773439,\n              38.97222194853654\n            ],\n            [\n              -119.95353698730469,\n              38.98449904830041\n            ],\n            [\n              -119.9480438232422,\n              38.99036995221769\n            ],\n            [\n              -119.9542236328125,\n              39.00104307544137\n            ],\n            [\n              -119.94461059570311,\n              39.00584545569229\n            ],\n            [\n              -119.9480438232422,\n              39.01865020920716\n            ],\n            [\n              -119.9439239501953,\n              39.02291794517652\n            ],\n            [\n              -119.94529724121092,\n              39.0421195689398\n            ],\n            [\n              -119.93843078613281,\n              39.06984603648688\n            ],\n            [\n              -119.94255065917967,\n              39.08477116318522\n            ],\n            [\n              -119.93431091308594,\n              39.08850195155841\n            ],\n            [\n              -119.94461059570311,\n              39.102357437817595\n            ],\n            [\n              -119.95491027832031,\n              39.10821855471585\n            ],\n            [\n              -119.95010375976562,\n              39.12313556216662\n            ],\n            [\n              -119.937744140625,\n              39.128994951066765\n            ],\n            [\n              -119.93911743164062,\n              39.13911456561877\n            ],\n            [\n              -119.93019104003905,\n              39.1465701930969\n            ],\n            [\n              -119.92675781249999,\n              39.17212634923011\n            ],\n            [\n              -119.9212646484375,\n              39.17691709496078\n            ],\n            [\n              -119.92538452148438,\n              39.20299431736876\n            ],\n            [\n              -119.92332458496094,\n              39.22055107521368\n            ],\n            [\n              -119.92675781249999,\n              39.22587043822116\n            ],\n            [\n              -119.92881774902342,\n              39.23384872688399\n            ],\n            [\n              -119.94529724121092,\n              39.242357901670495\n            ],\n            [\n              -119.97276306152344,\n              39.25086604435735\n            ],\n            [\n              -119.99267578124999,\n              39.25299291875617\n            ],\n            [\n              -120.00503540039061,\n              39.24501680713314\n            ],\n            [\n              -120.00846862792967,\n              39.22959375247292\n            ],\n            [\n              -120.02220153808592,\n              39.24023070473076\n            ],\n            [\n              -120.05722045898439,\n              39.24342147595056\n            ],\n            [\n              -120.07301330566408,\n              39.238103443285794\n            ],\n            [\n              -120.07301330566408,\n              39.22959375247292\n            ],\n            [\n              -120.08880615234376,\n              39.22959375247292\n            ],\n            [\n              -120.09292602539062,\n              39.212571274892355\n            ],\n            [\n              -120.09979248046874,\n              39.207782959371684\n            ],\n            [\n              -120.10047912597655,\n              39.18969082109678\n            ],\n            [\n              -120.12794494628906,\n              39.18596539075659\n            ],\n            [\n              -120.14579772949217,\n              39.17478791493289\n            ],\n            [\n              -120.16159057617186,\n              39.16307627231444\n            ],\n            [\n              -120.14785766601561,\n              39.15934943158527\n            ],\n            [\n              -120.14923095703124,\n              39.15083019711799\n            ],\n            [\n              -120.15815734863281,\n              39.144972625112224\n            ],\n            [\n              -120.15815734863281,\n              39.13432124527173\n            ],\n            [\n              -120.16983032226562,\n              39.128994951066765\n            ],\n            [\n              -120.1636505126953,\n              39.11461194459293\n            ],\n            [\n              -120.16914367675781,\n              39.103955972576166\n            ],\n            [\n              -120.16708374023438,\n              39.086370096650704\n            ],\n            [\n              -120.14923095703124,\n              39.069312937859586\n            ],\n            [\n              -120.11901855468751,\n              39.058650119748236\n            ],\n            [\n              -120.11695861816405,\n              39.049585458080685\n            ],\n            [\n              -120.1306915283203,\n              39.03571960736407\n            ],\n            [\n              -120.12176513671875,\n              39.029852466679316\n            ],\n            [\n              -120.12657165527344,\n              39.02238449226849\n            ],\n            [\n              -120.12039184570312,\n              39.00851330385611\n            ],\n            [\n              -120.10047912597655,\n              38.99410572845627\n            ],\n            [\n              -120.09979248046874,\n              38.97168811330431\n            ],\n            [\n              -120.09635925292969,\n              38.966349539681055\n            ],\n            [\n              -120.11558532714842,\n              38.95406929344106\n            ],\n            [\n              -120.10665893554688,\n              38.94445718138944\n            ],\n            [\n              -120.08399963378905,\n              38.94979740456155\n            ],\n            [\n              -120.06271362304688,\n              38.93751428984747\n            ],\n            [\n              -120.02494812011717,\n              38.93217314143696\n            ],\n            [\n              -120.02563476562501,\n              38.923626467304864\n            ],\n            [\n              -119.99885559082031,\n              38.92522904714054\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"112","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5e50e4b0c8380cd7095b","contributors":{"authors":[{"text":"Gardner, J.V.","contributorId":76705,"corporation":false,"usgs":true,"family":"Gardner","given":"J.V.","affiliations":[],"preferred":false,"id":393554,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mayer, L. A.","contributorId":105776,"corporation":false,"usgs":true,"family":"Mayer","given":"L.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":393556,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hughs, Clarke J.E.","contributorId":92457,"corporation":false,"usgs":true,"family":"Hughs","given":"Clarke","email":"","middleInitial":"J.E.","affiliations":[],"preferred":false,"id":393555,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022416,"text":"70022416 - 2000 - New structural and stratigraphic insights for northwestern Pakistan from field and Landsat Thematic Mapper data","interactions":[],"lastModifiedDate":"2022-09-22T16:04:47.535501","indexId":"70022416","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","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":"New structural and stratigraphic insights for northwestern Pakistan from field and Landsat Thematic Mapper data","docAbstract":"The remote Waziristan region of northwestern Pakistan includes outcrops of the India-Asia suture zone. The excellent exposure of the Waziristan ophiolite and associated sedimentary lithosomes and their inaccessibility made the use of Landsat Thematic Mapper (TM) data desirable in this study. Landsat TM data were used to create a spectral ratio image of bands 3/4, 5/4, and 7/5, displayed as red, green, and blue, respectively, and a principal component analysis image of bands 4, 5, and 7 (RGB). These images were interpreted in the context of available geologic maps, limited field work, and biostratigraphic, lithostratigraphic, and radiometric data. They were used to create a coherent geologic map of Waziristan and cross section of the area that document five tectonic units in the region and provide a new and more detailed tectonic history for the region. The lowest unit is comprised of Indian shelf sediments that were thrust under the Waziristan ophiolite. The ophiolite has been tectonically shuffled and consists of two separate tectonic units. The top thrust sheet is a nappe comprised of distal Triassic to Lower Cretaceous Neotethyan sediments that were underthrust during the Late Cretaceous by the ophiolite riding on Indian shelf strata. The uppermost unit contains unconformable Tertiary and younger strata. The thrust sheets show that the Waziristan ophiolite was obducted during Late Cretaceous time and imply that the Paleocene and Eocene deformation represents collision of India with the Kabul block and/or Asia.","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(2000)112<364:NSASIF>2.0.CO;2","issn":"00167606","usgsCitation":"Robinson, J., Beck, R., Gnos, E., and Vincent, R., 2000, New structural and stratigraphic insights for northwestern Pakistan from field and Landsat Thematic Mapper data: Geological Society of America Bulletin, v. 112, no. 3, p. 364-374, https://doi.org/10.1130/0016-7606(2000)112<364:NSASIF>2.0.CO;2.","productDescription":"11 p.","startPage":"364","endPage":"374","costCenters":[],"links":[{"id":230832,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Pakistan","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              69.862060546875,\n              32.602361666817515\n            ],\n            [\n              70.90576171875,\n              32.602361666817515\n            ],\n            [\n              70.90576171875,\n              33.46810795527896\n            ],\n            [\n              69.862060546875,\n              33.46810795527896\n            ],\n            [\n              69.862060546875,\n              32.602361666817515\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"112","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6617e4b0c8380cd72d06","contributors":{"authors":[{"text":"Robinson, J.","contributorId":73723,"corporation":false,"usgs":false,"family":"Robinson","given":"J.","affiliations":[{"id":6987,"text":"U.S. Fish and Wildlife Sevice","active":true,"usgs":false}],"preferred":false,"id":393553,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Beck, R.","contributorId":21721,"corporation":false,"usgs":true,"family":"Beck","given":"R.","email":"","affiliations":[],"preferred":false,"id":393551,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gnos, E.","contributorId":53555,"corporation":false,"usgs":true,"family":"Gnos","given":"E.","email":"","affiliations":[],"preferred":false,"id":393552,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Vincent, R.K.","contributorId":9766,"corporation":false,"usgs":true,"family":"Vincent","given":"R.K.","email":"","affiliations":[],"preferred":false,"id":393550,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70022415,"text":"70022415 - 2000 - Determination of geochemical affinities of granitic rocks from the Aue-Schwarzenberg zone (Erzgebirge, Germany) by multivariate statistics","interactions":[],"lastModifiedDate":"2012-03-12T17:19:42","indexId":"70022415","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2857,"text":"Neues Jahrbuch fur Mineralogie, Monatshefte","active":true,"publicationSubtype":{"id":10}},"title":"Determination of geochemical affinities of granitic rocks from the Aue-Schwarzenberg zone (Erzgebirge, Germany) by multivariate statistics","docAbstract":"Variscan granites of the Erzgebirge region can be effectively classified into five genetically distinct major groups by canonical analysis of geochemical variables. The same classification procedure, when applied to small plutons in the Aue-Schwarzenberg granite zone (ASGZ), shows that all ASGZ granites have compositional affinities to low-F biotite or low-F two-mica granite groups. This suggests that the ASGZ granites were emplaced during the first, late-collisional stage of silicic magmatism in the region, which occurred between about 325 and 318 Ma. The numerous biotite granite bodies in the zone are geochemically distinct from both the neighboring Kirchberg granite pluton and the spatially displaced Niederbobritzsch biotite granite massif. Instead, these bodies seem to constitute a third sub-group within the low-F biotite granite class. The ASGZ biotite granites represent three or more genetically distinct bodies, thus highlighting the enormous compositional variability within this group of granites. Least evolved samples of two-mica granites from the ASGZ apparently reflect the assimilation of low-grade metamorphic country rocks during emplacement, altering the original composition of the melts by enhancing primary Al content. The same genesis is implied for the rare \"cordierite granite\" facies of the Bergen massif, the type pluton for the low-F two-mica granite group in the Erzgebirge.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Neues Jahrbuch fur Mineralogie, Monatshefte","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"00283649","usgsCitation":"Forster, H., and Davis, J., 2000, Determination of geochemical affinities of granitic rocks from the Aue-Schwarzenberg zone (Erzgebirge, Germany) by multivariate statistics: Neues Jahrbuch fur Mineralogie, Monatshefte, v. 12, p. 529-542.","startPage":"529","endPage":"542","numberOfPages":"14","costCenters":[],"links":[{"id":230798,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ffa7e4b0c8380cd4f2f5","contributors":{"authors":[{"text":"Forster, H.-J.","contributorId":104653,"corporation":false,"usgs":true,"family":"Forster","given":"H.-J.","email":"","affiliations":[],"preferred":false,"id":393549,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Davis, J.C.","contributorId":72121,"corporation":false,"usgs":true,"family":"Davis","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":393548,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70022387,"text":"70022387 - 2000 - Influence of acid volatile sulfide and metal concentrations on metal bioavailability to marine invertebrates in contaminated sediments","interactions":[],"lastModifiedDate":"2018-12-03T10:30:55","indexId":"70022387","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","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":"Influence of acid volatile sulfide and metal concentrations on metal bioavailability to marine invertebrates in contaminated sediments","docAbstract":"<div class=\"hlFld-Abstract\"><div id=\"abstractBox\"><p class=\"articleBody_abstractText\">An 18-day microcosm study was conducted to evaluate the influence of acid volatile sulfides (AVS) and metal additions on bioaccumulation from sediments of Cd, Ni, and Zn in two clams (<i>Macoma balthica</i><span>&nbsp;</span>and<span>&nbsp;</span><i>Potamocorbula amurensis</i>) and three marine polychaetes (<i>Neanthes arenaceodentata, Heteromastus filiformis,</i><span>&nbsp;</span>and<span>&nbsp;</span><i>Spiophanes missionensis</i>). Manipulation of AVS by oxidation of naturally anoxic sediments allowed use of metal concentrations typical of nature and evaluation of processes important to chronic metal exposure. A vertical sediment column similar to that often found in nature was used to facilitate realistic biological behavior. Results showed that AVS or porewater (PW) metals controlled bioaccumulation in only 2 of 15 metal-animal combinations. Bioaccumulation of all three metals by the bivalves was related significantly to metal concentrations extracted from sediments (SEM) but not to [SEM − AVS] or PW metals. SEM predominantly influenced bioaccumulation of Ni and Zn in<span>&nbsp;</span><i>N. arenaceodentata</i>, but Cd bioaccumulation followed PW Cd concentrations. SEM controlled tissue concentrations of all three metals in<span>&nbsp;</span><i>H. filiformis</i><span>&nbsp;</span>and<span>&nbsp;</span><i>S. missionensis</i>, with minor influences from metal-sulfide chemistry. Significant bioaccumulation occurred when SEM was only a small fraction of AVS in several treatments. Three factors appeared to contribute to the differences between these bioaccumulation results and the results from toxicity tests reported previously:  differences in experimental design, dietary uptake, and biological attributes of the species, including mode and depth of feeding.</p></div></div>","language":"English","publisher":"ACS","doi":"10.1021/es001033h","issn":"0013936X","usgsCitation":"Lee, B., Lee, J., Luoma, S., Choi, H., and Koh, C., 2000, Influence of acid volatile sulfide and metal concentrations on metal bioavailability to marine invertebrates in contaminated sediments: Environmental Science & Technology, v. 34, no. 21, p. 4517-4523, https://doi.org/10.1021/es001033h.","productDescription":"7 p.","startPage":"4517","endPage":"4523","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230345,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206596,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es001033h"}],"volume":"34","issue":"21","noUsgsAuthors":false,"publicationDate":"2000-09-15","publicationStatus":"PW","scienceBaseUri":"505a3b0ae4b0c8380cd621a6","contributors":{"authors":[{"text":"Lee, B.-G.","contributorId":11777,"corporation":false,"usgs":true,"family":"Lee","given":"B.-G.","email":"","affiliations":[],"preferred":false,"id":393452,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lee, J.-S.","contributorId":15787,"corporation":false,"usgs":true,"family":"Lee","given":"J.-S.","email":"","affiliations":[],"preferred":false,"id":393453,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Luoma, S. N.","contributorId":86353,"corporation":false,"usgs":true,"family":"Luoma","given":"S. N.","affiliations":[],"preferred":false,"id":393454,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Choi, H.J.","contributorId":105466,"corporation":false,"usgs":true,"family":"Choi","given":"H.J.","email":"","affiliations":[],"preferred":false,"id":393455,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Koh, C.-H.","contributorId":9797,"corporation":false,"usgs":true,"family":"Koh","given":"C.-H.","email":"","affiliations":[],"preferred":false,"id":393451,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}}
,{"id":70022383,"text":"70022383 - 2000 - Annual bed-elevation regime in the alluvial channel of Squamish River, southwestern British Columbia Canada","interactions":[],"lastModifiedDate":"2012-03-12T17:19:49","indexId":"70022383","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1425,"text":"Earth Surface Processes and Landforms","active":true,"publicationSubtype":{"id":10}},"title":"Annual bed-elevation regime in the alluvial channel of Squamish River, southwestern British Columbia Canada","docAbstract":"The aim of this study is to examine the annual regime of channel scour and fill by monitoring bed-elevation changes in a reach of Squamish River in southwestern British Columbia, Canada. Sonar surveys of 13 river cross-sections in a sandy gravel-bed single-channel study reach were repeated biweekly over a full hydrologic year (1995/6). The survey results show that bedload movement occurs as waves or pulses forming bedwaves that appear to maintain an overall coherence with movement downstream. These bedwaves propagate downstream by a mode here termed pulse scour and pulse fill, a process distinguished from the conventional mode of scour and fill commonly associated with flood events (here termed local scour and local fill). Bedwave celerity was estimated to be about 15.5 m d-1 corresponding to a bedwave residence time in the study reach of almost one hydrologic year. The total amount of local bed-elevation change ranged between 0.22 m and 2.41 m during the period of study. Analysis of the bed-elevation and flow data reveals that, because of the bedware phenomenon, there is no simple relation between the mean bed-elevation and discharge nor any strong linear correlation among cross-sectional behaviour. The bed-elevation data also suggest that complex changes to the bed within a cross-section are masked when the bed is viewed in one dimension, although no definitive trends in bed behaviour were found in the two-dimensional analysis. Although a weak seasonal effect is evident in this study, the bed-elevation regime is dominated by sediment supply-driven fluctuations in bedload transport occurring at timescales shorter than the seasonal fluctuation in discharge. The study also indicates that bed-elevation monitoring on Squamish River, and others like it, for purposes of detecting and measuring aggradation/degradation must take into account very considerable and normal channel-bed variability operating at timescales from hours to months. Copyright (C) 2000 John Wiley and Sons, Ltd.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Earth Surface Processes and Landforms","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1002/1096-9837(200008)25:9<991::AID-ESP113>3.0.CO;2-W","issn":"01979337","usgsCitation":"Stanford, S., Seidl, M., and Ashley, G., 2000, Annual bed-elevation regime in the alluvial channel of Squamish River, southwestern British Columbia Canada: Earth Surface Processes and Landforms, v. 25, no. 9, p. 991-1009, https://doi.org/10.1002/1096-9837(200008)25:9<991::AID-ESP113>3.0.CO;2-W.","startPage":"991","endPage":"1009","numberOfPages":"19","costCenters":[],"links":[{"id":206583,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1002/1096-9837(200008)25:9<991::AID-ESP113>3.0.CO;2-W"},{"id":230300,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ec1ee4b0c8380cd490b0","contributors":{"authors":[{"text":"Stanford, S.D.","contributorId":79932,"corporation":false,"usgs":true,"family":"Stanford","given":"S.D.","email":"","affiliations":[],"preferred":false,"id":393439,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Seidl, M.A.","contributorId":84532,"corporation":false,"usgs":true,"family":"Seidl","given":"M.A.","email":"","affiliations":[],"preferred":false,"id":393440,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ashley, G.M.","contributorId":99313,"corporation":false,"usgs":true,"family":"Ashley","given":"G.M.","email":"","affiliations":[],"preferred":false,"id":393441,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022382,"text":"70022382 - 2000 - Oil and gas reserve growth-a model for the Volga-Ural Province, Russia","interactions":[],"lastModifiedDate":"2012-03-12T17:19:46","indexId":"70022382","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Oil and gas reserve growth-a model for the Volga-Ural Province, Russia","docAbstract":"An understanding of reserve growth in known oil and gas fields has become a critical component of energy resource analysis. Significant statistical studies of reserve growth have been published in the U.S., whereas little information is available on other regions of the world. It may be expected that in many countries the magnitude of reserve growth is different from that in the U.S. because of differences in reporting systems and in exploration and production practices. This paper describes the results of a reserve growth study in a group of largest oil and gas fields of the Volga-Ural petroleum province, Russia. The dynamics of reserve growth in these fields shows rapid reserve additions during the first 5 years of field exploration and development, which results from intensive step-out and delineation drilling. Later reserve growth is slow and is related to improvements in recovery technologies and discoveries of new pools and extensions. These two stages of reserve growth are described by two different groups of empirical models. A comparison of these models with the models developed for the lower 48 states and Gulf Coast offshore of the U.S. demonstrates that the reserve growth in the Volga-Ural province is significantly lower than in the U.S. The proposed models may be used for assessment of future reserve additions in known fields of countries that presently have or recently had a centrally-planned economic system.","largerWorkTitle":"SPE/AAPG Western Regional Meetings","conferenceTitle":"SPE/AAPG Western Regional Meetings","conferenceDate":"19 June 2000 through 23 June 2000","conferenceLocation":"Long Beach, CA","language":"English","usgsCitation":"Verma, M., Ulmishek, G., and Gilbershtein, A., 2000, Oil and gas reserve growth-a model for the Volga-Ural Province, Russia, <i>in</i> SPE/AAPG Western Regional Meetings, Long Beach, CA, 19 June 2000 through 23 June 2000, p. 555-564.","startPage":"555","endPage":"564","numberOfPages":"10","costCenters":[],"links":[{"id":230871,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6ce8e4b0c8380cd74e7e","contributors":{"authors":[{"text":"Verma, M.K.","contributorId":90375,"corporation":false,"usgs":true,"family":"Verma","given":"M.K.","email":"","affiliations":[],"preferred":false,"id":393438,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ulmishek, G. F.","contributorId":89144,"corporation":false,"usgs":true,"family":"Ulmishek","given":"G. F.","affiliations":[],"preferred":false,"id":393437,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gilbershtein, A.P.","contributorId":55602,"corporation":false,"usgs":true,"family":"Gilbershtein","given":"A.P.","email":"","affiliations":[],"preferred":false,"id":393436,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022381,"text":"70022381 - 2000 - A method for producing digital probabilistic seismic landslide hazard maps","interactions":[],"lastModifiedDate":"2012-03-12T17:19:46","indexId":"70022381","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1517,"text":"Engineering Geology","active":true,"publicationSubtype":{"id":10}},"title":"A method for producing digital probabilistic seismic landslide hazard maps","docAbstract":"The 1994 Northridge, California, earthquake is the first earthquake for which we have all of the data sets needed to conduct a rigorous regional analysis of seismic slope instability. These data sets include: (1) a comprehensive inventory of triggered landslides, (2) about 200 strong-motion records of the mainshock, (3) 1:24 000-scale geologic mapping of the region, (4) extensive data on engineering properties of geologic units, and (5) high-resolution digital elevation models of the topography. All of these data sets have been digitized and rasterized at 10 m grid spacing using ARC/INFO GIS software on a UNIX computer. Combining these data sets in a dynamic model based on Newmark's permanent-deformation (sliding-block) analysis yields estimates of coseismic landslide displacement in each grid cell from the Northridge earthquake. The modeled displacements are then compared with the digital inventory of landslides triggered by the Northridge earthquake to construct a probability curve relating predicted displacement to probability of failure. This probability function can be applied to predict and map the spatial variability in failure probability in any ground-shaking conditions of interest. We anticipate that this mapping procedure will be used to construct seismic landslide hazard maps that will assist in emergency preparedness planning and in making rational decisions regarding development and construction in areas susceptible to seismic slope failure. ?? 2000 Elsevier Science B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Engineering Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0013-7952(00)00039-9","issn":"00137952","usgsCitation":"Jibson, R., Harp, E.L., and Michael, J.A., 2000, A method for producing digital probabilistic seismic landslide hazard maps: Engineering Geology, v. 58, no. 3-4, p. 271-289, https://doi.org/10.1016/S0013-7952(00)00039-9.","startPage":"271","endPage":"289","numberOfPages":"19","costCenters":[],"links":[{"id":206822,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0013-7952(00)00039-9"},{"id":230870,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"58","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e456e4b0c8380cd465c4","contributors":{"authors":[{"text":"Jibson, R.W.","contributorId":8467,"corporation":false,"usgs":true,"family":"Jibson","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":393433,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Harp, E. L.","contributorId":59026,"corporation":false,"usgs":true,"family":"Harp","given":"E.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":393435,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Michael, J. A.","contributorId":48567,"corporation":false,"usgs":true,"family":"Michael","given":"J.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":393434,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022380,"text":"70022380 - 2000 - The effects of gap size and disturbance type on invasion of wet pine savanna by cogongrass, Imperata cylindrica (Poaceae)","interactions":[],"lastModifiedDate":"2019-06-04T12:11:38","indexId":"70022380","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":724,"text":"American Journal of Botany","active":true,"publicationSubtype":{"id":10}},"title":"The effects of gap size and disturbance type on invasion of wet pine savanna by cogongrass, Imperata cylindrica (Poaceae)","docAbstract":"Cogongrass is a nonindigenous species perceived to threaten native communities of the southeastern United States through modification of species composition and alteration of community processes. To examine how gap size and disturbance type influence the invasion of wet pine savannas by cogongrass, we performed three field experiments to evaluate the response of cogongrass seeds and transplanted seedlings to four different gap sizes, four types of site disturbance, and recent burning of savanna vegetation. Cogongrass germinated, survived, and grew in all gap sizes, from 0 to 100 cm in diameter. Similarly, disturbance type had no effect on germination or seedling and transplant survival. Tilling, however, significantly enhanced transplanted seedling growth, resulting in a tenfold increase in biomass over the other disturbance types. Seedling survival to 1 and 2 mo was greater in burned savanna than unburned savanna, although transplant survival and growth were not affected by burning. Results of this study suggest that cogongrass can germinate, survive, and grow in wet pine savanna communities regardless of gap size or type of disturbance, including burning. Burning of savanna vegetation may enhance establishment by improving early seedling survival, and soil disturbance can facilitate invasion of cogongrass by enhancing plant growth.","language":"English","publisher":"Botanical Society of America","doi":"10.2307/2656721","issn":"00029122","usgsCitation":"King, S., and Grace, J., 2000, The effects of gap size and disturbance type on invasion of wet pine savanna by cogongrass, Imperata cylindrica (Poaceae): American Journal of Botany, v. 87, no. 9, p. 1279-1286, https://doi.org/10.2307/2656721.","productDescription":"8 p.","startPage":"1279","endPage":"1286","numberOfPages":"8","costCenters":[{"id":17705,"text":"Wetland and Aquatic Research Center","active":true,"usgs":true}],"links":[{"id":230831,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"87","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bab7de4b08c986b322e9e","contributors":{"authors":[{"text":"King, S.E. 0000-0001-5698-4588","orcid":"https://orcid.org/0000-0001-5698-4588","contributorId":47939,"corporation":false,"usgs":true,"family":"King","given":"S.E.","email":"","affiliations":[],"preferred":false,"id":393432,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Grace, J.B. 0000-0001-6374-4726","orcid":"https://orcid.org/0000-0001-6374-4726","contributorId":38938,"corporation":false,"usgs":true,"family":"Grace","given":"J.B.","affiliations":[],"preferred":false,"id":393431,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70022378,"text":"70022378 - 2000 - Bacteria and Archaea in acidic environments and a key to morphological identification","interactions":[],"lastModifiedDate":"2012-03-12T17:19:47","indexId":"70022378","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1919,"text":"Hydrobiologia","onlineIssn":"1573-5117","printIssn":"0018-8158","active":true,"publicationSubtype":{"id":10}},"title":"Bacteria and Archaea in acidic environments and a key to morphological identification","docAbstract":"Natural and anthropogenic acidic environments are dominated by bacteria and Archaea. As many as 86 genera or species have been identified or isolated from pH <4.5 environments. This paper reviews the worldwide literature and provide tables of morphological characteristics, habitat information and a key for light microscope identification for the non-microbiologist.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrobiologia","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1023/A:1004062519263","issn":"00188158","usgsCitation":"Robbins, E.I., 2000, Bacteria and Archaea in acidic environments and a key to morphological identification: Hydrobiologia, v. 433, p. 61-89, https://doi.org/10.1023/A:1004062519263.","startPage":"61","endPage":"89","numberOfPages":"29","costCenters":[],"links":[{"id":206806,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1004062519263"},{"id":230829,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"433","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ef99e4b0c8380cd4a33a","contributors":{"authors":[{"text":"Robbins, E. I.","contributorId":101269,"corporation":false,"usgs":true,"family":"Robbins","given":"E.","email":"","middleInitial":"I.","affiliations":[],"preferred":false,"id":393428,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70022377,"text":"70022377 - 2000 - Acoustic properties of a crack containing magmatic or hydrothermal fluids","interactions":[],"lastModifiedDate":"2022-09-07T15:04:42.885399","indexId":"70022377","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","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":"Acoustic properties of a crack containing magmatic or hydrothermal fluids","docAbstract":"<p>We estimate the acoustic properties of a crack containing magmatic or hydrothermal fluids to quantify the source properties of long-period (LP) events observed in volcanic areas assuming that a crack-like structure is the source of LP events. The tails of synthetic waveforms obtained from a model of a fluid-driven crack are analyzed by the Sompi method to determine the complex frequencies of one of the modes of crack resonance over a wide range of the model parameters α/<i>a</i><span>&nbsp;</span>and ρ<sub><i>f</i></sub>/ρ<sub><i>s</i></sub>, where αis the<span>&nbsp;</span><i>P</i><span>&nbsp;</span>wave velocity of the rock matrix,<span>&nbsp;</span><i>a</i><span>&nbsp;</span>is the sound speed of the fluid, and ρ<sub><i>f</i></sub><span>&nbsp;</span>and<span>&nbsp;</span><i>p<sub>s</sub></i><span>&nbsp;</span>are the densities of the fluid and rock matrix, respectively. The quality factor due to radiation loss (<i>Q<sub>r</sub></i>) for the selected mode almost monotonically increases with increasing α/<i>a</i>, while the dimensionless frequency (<i>v</i>) of the mode decreases with increasing α/<i>a</i><span>&nbsp;</span>and ρ<sub><i>f</i></sub>/ρ<sub><i>s</i></sub>. These results are used to estimate<span>&nbsp;</span><i>Q</i><span>&nbsp;</span>and<span>&nbsp;</span><i>v</i><span>&nbsp;</span>for a crack containing various types of fluids (gas-gas mixtures, liquid-gas mixtures, and dusty and misty gases) for values of<span>&nbsp;</span><i>a</i>, ρ<sub><i>f</i></sub>, and quality factor due to intrinsic losses (<i>Q<sub>i</sub></i>) appropriate for these types of fluids, in which<span>&nbsp;</span><i>Q</i><span>&nbsp;</span>is given by<span>&nbsp;</span><i>Q</i><sup>−l</sup><span>&nbsp;</span>=<span>&nbsp;</span><i>Q</i><sub>r</sub><sup>−l</sup><span>&nbsp;</span>+<span>&nbsp;</span><i>Q</i><sub>i</sub><sup>−1</sup>. For a crack containing such fluids, we obtain<span>&nbsp;</span><i>Q</i><span>&nbsp;</span>ranging from almost unity to several hundred, which consistently explains the wide variety of quality factors measured in LP events observed at various volcanoes. We underscore the importance of dusty and misty gases containing small-size particles with radii around 1 μm to explain long-lasting oscillations with<span>&nbsp;</span><i>Q</i><span>&nbsp;</span>significantly larger than 100. Our results may provide a basis for the interpretation of spatial and temporal variations in the observed complex frequencies of LP events in terms of fluid compositions beneath volcanoes.</p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000JB900273","issn":"01480227","usgsCitation":"Kumagai, H., and Chouet, B., 2000, Acoustic properties of a crack containing magmatic or hydrothermal fluids: Journal of Geophysical Research B: Solid Earth, v. 105, no. B11, p. 25493-25512, https://doi.org/10.1029/2000JB900273.","productDescription":"20 p.","startPage":"25493","endPage":"25512","costCenters":[],"links":[{"id":230796,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"105","issue":"B11","noUsgsAuthors":false,"publicationDate":"2000-11-10","publicationStatus":"PW","scienceBaseUri":"5059e69fe4b0c8380cd4753c","contributors":{"authors":[{"text":"Kumagai, Hiroyuki","contributorId":71337,"corporation":false,"usgs":false,"family":"Kumagai","given":"Hiroyuki","email":"","affiliations":[],"preferred":false,"id":393427,"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":393426,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70022375,"text":"70022375 - 2000 - Orbital and suborbital variability in North Atlantic bottom water temperature obtained from deep-sea ostracod Mg/Ca ratios","interactions":[],"lastModifiedDate":"2017-05-10T16:18:58","indexId":"70022375","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2996,"text":"Palaeogeography, Palaeoclimatology, Palaeoecology","printIssn":"0031-0182","active":true,"publicationSubtype":{"id":10}},"title":"Orbital and suborbital variability in North Atlantic bottom water temperature obtained from deep-sea ostracod Mg/Ca ratios","docAbstract":"<p id=\"\">Magnesium/calcium (Mg/Ca) ratios were measured in the deep-sea ostracod (Crustacea) genus <i>Krithe</i> from <i>Chain</i> core 82-24-4PC from the western mid-Atlantic Ridge (3427&nbsp;m) in order to estimate ocean circulation and bottom water temperature (BWT) variability over the past 200,000&nbsp;years. Mg/Ca ratios have been used as a paleothermometer because the ratios are controlled primarily by ambient water temperatures at the time the organism secretes its adult carapace. Over the past two glacial–interglacial cycles, Mg/Ca values oscillated between about 7&nbsp;mmol/mol and 12&nbsp;mmol/mol, equivalent to a BWT range of 0 to &gt;3.5°C. The lowest values were obtained on specimens from glacial marine isotope stages (MISs) 2, 4 and 6; the highest values were obtained from specimens from the early part of the Holocene interglacial (MIS 1), and also from MISs 5 and 7. These trends suggest that BWTs in the North Atlantic Ocean fluctuate over orbital time scales.</p><p id=\"\">Suborbital variability in Mg/Ca ratios and BWT was also observed for the past 100,000&nbsp;years. Ratios rose from ∼8&nbsp;mmol/mol to ∼10&nbsp;mmol/mol (implying a BWT increase of ∼1 to 3°C) during 14 Mg/Ca excursions. The highest ratios were found in <i>Krithe</i> dated at approximately 32, 36–38, 43, 48, 73, 85 and 93&nbsp;ka. Although the age model for the <i>Chain</i> 82-24-4PC and temporal resolution do not allow precise correlation, some of these deep-sea bottom temperature excursions appear to correspond to Heinrich events recorded in other regions of the North Atlantic and perhaps Dansgaard–Oeschger interstadial events recorded in Greenland ice cores. If confirmed, this would support the hypothesis that millennial-scale oscillations of climate in the North Atlantic are capable of affecting global climate via thermohaline circulation changes.</p>","language":"English","publisher":"Elsevier","doi":"10.1016/S0031-0182(00)00104-8","issn":"00310182","usgsCitation":"Cronin, T.M., Dwyer, G.S., Baker, P., Rodriguez-Lazaro, J., and DeMartino, D., 2000, Orbital and suborbital variability in North Atlantic bottom water temperature obtained from deep-sea ostracod Mg/Ca ratios: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 162, no. 1-2, p. 45-57, https://doi.org/10.1016/S0031-0182(00)00104-8.","productDescription":"13 p.","startPage":"45","endPage":"57","costCenters":[],"links":[{"id":487322,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"http://hdl.handle.net/10161/6479","text":"External Repository"},{"id":230754,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"162","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6f2de4b0c8380cd75994","contributors":{"authors":[{"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":393421,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dwyer, G. S.","contributorId":39951,"corporation":false,"usgs":true,"family":"Dwyer","given":"G.","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":393420,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Baker, P.A.","contributorId":55148,"corporation":false,"usgs":true,"family":"Baker","given":"P.A.","email":"","affiliations":[],"preferred":false,"id":393422,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Rodriguez-Lazaro, J.","contributorId":92002,"corporation":false,"usgs":true,"family":"Rodriguez-Lazaro","given":"J.","affiliations":[],"preferred":false,"id":393423,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"DeMartino, D.M.","contributorId":11789,"corporation":false,"usgs":true,"family":"DeMartino","given":"D.M.","email":"","affiliations":[],"preferred":false,"id":393419,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}}
,{"id":70022370,"text":"70022370 - 2000 - Mercury mine drainage and processes that control its environmental impact","interactions":[],"lastModifiedDate":"2012-03-12T17:19:42","indexId":"70022370","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3352,"text":"Science of the Total Environment","active":true,"publicationSubtype":{"id":10}},"title":"Mercury mine drainage and processes that control its environmental impact","docAbstract":"Mine drainage from mercury mines in the California Coast Range mercury mineral belt is an environmental concern because of its acidity and high sulfate, mercury, and methylmercury concentrations. Two types of mercury deposits are present in the mineral belt, silica-carbonate and hot-spring type. Mine drainage is associated with both deposit types but more commonly with the silica-carbonate type because of the extensive underground workings present at these mines. Mercury ores consisting primarily of cinnabar were processed in rotary furnaces and retorts and elemental mercury recovered from condensing systems. During the roasting process mercury phases more soluble than cinnabar are formed and concentrated in the mine tailings, commonly termed calcines. Differences in mineralogy and trace metal geochemistry between the two deposit types are reflected in mine drainage composition. Silica-carbonate type deposits have higher iron sulfide content than hot- spring type deposits and mine drainage from these deposits may have extreme acidity and very high concentrations of iron and sulfate. Mercury and methylmercury concentrations in mine drainage are relatively low at the point of discharge from mine workings. The concentration of both mercury species increases significantly in mine drainage that flows through and reacts with calcines. The soluble mercury phases in the calcines are dissolved and sulfate is added such that methylation of mercury by sulfate reducing bacteria is enhanced in calcines that are saturated with mine drainage. Where mercury mine drainage enters and first mixes with stream water, the addition of high concentrations of mercury and sulfate generates a favorable environment for methylation of mercury. Mixing of oxygenated stream water with mine drainage causes oxidation of dissolved iron(II) and precipitation of iron oxyhydroxide that accumulates in the streambed. Both mercury and methylmercury are strongly adsorbed onto iron oxyhydroxide over the pH range of 3.2-7.1 in streams impacted by mine drainage. The dissolved fraction of both mercury species is depleted and concentrated in iron oxyhydroxide such that the amount of iron oxyhydroxide in the water column reflects the concentration of mercury species. In streams impacted by mine drainage, mercury and methylmercury are transported and adsorbed onto particulate phases. During periods of low stream flow, fine-grained iron hydroxide sediment accumulates in the bed load of the stream and adsorbs mercury and methylmercury such that both forms of mercury become highly enriched in the iron oxyhydroxide sediment. During high-flow events, mercury- and methylmercury-enriched iron hydroxide sediment is transported into larger aquatic systems producing a high flux of bioavailable mercury. (C) 2000 Elsevier Science B.V.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Science of the Total Environment","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0048-9697(00)00541-6","issn":"00489697","usgsCitation":"Rytuba, J.J., 2000, Mercury mine drainage and processes that control its environmental impact: Science of the Total Environment, v. 260, no. 1-3, p. 57-71, https://doi.org/10.1016/S0048-9697(00)00541-6.","startPage":"57","endPage":"71","numberOfPages":"15","costCenters":[],"links":[{"id":206739,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0048-9697(00)00541-6"},{"id":230677,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"260","issue":"1-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5424e4b0c8380cd6cec3","contributors":{"authors":[{"text":"Rytuba, J. J.","contributorId":83082,"corporation":false,"usgs":true,"family":"Rytuba","given":"J.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":393409,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70022369,"text":"70022369 - 2000 - The statistics and kinematics of transverse sand bars on an open coast","interactions":[],"lastModifiedDate":"2012-03-12T17:19:42","indexId":"70022369","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","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":"The statistics and kinematics of transverse sand bars on an open coast","docAbstract":"Ten years (1987-1996) of time exposure video images of the nearshore region at Duck, NC were used to study transverse sand bars, bathymetric features of intermediate length scales (10-200 m) oriented oblique or perpendicular to the shoreline. These transverse sand bars extend seaward from both the shoreline (trough transverse bars) and the shore-parallel sand bar (offshore transverse bars). Transverse bars had not previously been observed in an energetic Coastal environment such as that at Duck, and their dynamics and role in nearshore processes is unknown. Frequency of occurrence statistics and length scales of the transverse bars were calculated using the video images. Trough and offshore transverse bars appeared a mean of 39 and 73 days per year, respectively. The offshore bars were found to be much larger features than the trough bars, with mean wavelengths (alongshore spacing between consecutive crests) of 79 and 172 m for trough and offshore bars, respectively. Both the trough and offshore bars were found to persist for periods of days to months. The alongshore movement of the bars was measured and compared to estimates of surf zone longshore currents which were calculated from wave height and wave angle data. Both sets of bars were observed to move at rates up to 40 m/day. At times, both trough and offshore bars were observed shifting in the same direction as the current was flowing, and at other times, both sets of bars remained stationary, even under relatively strong longshore currents. Trough bars were also observed moving against the current. An hypothesis, proposed by Barcilon and Lau (1973) [J. Geophys. Res. 78(15): 2656-2664], that the transverse bars were created as a sea bed instability under longshore currents, was tested by comparing the magnitude of estimated surf zone longshore currents with times of formation or presence of transverse bars. There was no evidence to suggest that the bars were formed by this simple longshore current instability mechanism. Instead, it is plausible that the combined effects of waves and currents may drive the formation of these features. (C) 2000 Elsevier Science B.V.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0025-3227(00)00057-8","issn":"00253227","usgsCitation":"Konicki, K., and Holman, R., 2000, The statistics and kinematics of transverse sand bars on an open coast: Marine Geology, v. 169, no. 1-2, p. 69-101, https://doi.org/10.1016/S0025-3227(00)00057-8.","startPage":"69","endPage":"101","numberOfPages":"33","costCenters":[],"links":[{"id":206738,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0025-3227(00)00057-8"},{"id":230676,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"169","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb069e4b08c986b324e46","contributors":{"authors":[{"text":"Konicki, K.M.","contributorId":19325,"corporation":false,"usgs":true,"family":"Konicki","given":"K.M.","email":"","affiliations":[],"preferred":false,"id":393407,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Holman, R.A.","contributorId":73751,"corporation":false,"usgs":true,"family":"Holman","given":"R.A.","email":"","affiliations":[],"preferred":false,"id":393408,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70022368,"text":"70022368 - 2000 - Exposure age and erosional history of an upland planation surface in the US Atlantic Piedmont","interactions":[],"lastModifiedDate":"2012-03-12T17:19:42","indexId":"70022368","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1425,"text":"Earth Surface Processes and Landforms","active":true,"publicationSubtype":{"id":10}},"title":"Exposure age and erosional history of an upland planation surface in the US Atlantic Piedmont","docAbstract":"The upland planation surface in the Piedmont of central New Jersey consists of summit flats, as much as 130 km2 in area, that truncate bedding and structure in diabase, basalt, sandstone, mudstone and gneiss. These flats define a low-relief regional surface that corresponds in elevation to residual hills in the adjacent Coastal Plain capped by a fluvial gravel of late Miocene age. A Pliocene fluvial sand is inset 50 m below the upland features. These associations suggest a late Miocene or early Pliocene age for the surface. To assess exposure age and erosional history, a 4??4 m core of clayey diabase saprolite on a 3 km2 remnant of the surface was sampled at six depths for atmospherically produced cosmogenic 10Be. The measured inventory, assuming a deposition rate of 1??3 x 106 atoms cm-2 a-1, yields a minimum exposure age of 227 000 years, or, assuming continuous surface erosion, a constant erosion rate of 10 m Ma-1. Because the sample site lies about 60 m above the aggradation surface of the Pliocene fluvial deposit, and itself supports a pre-Pliocene fluvial gravel lag, this erosion rate is too high. Rather, episodic surface erosion and runoff bypassing probably have produced an inventory deficit. Reasonable estimates of surface erosion (up to 10 m) and bypassing (up to 50 per cent of total precipitation) yield exposure ages of as much as 6??4 Ma. These results indicate that (1) the surface is probably of pre-Pleistocene age and has been modified by Pleistocene erosion, and (2) exposure ages based on 10Be inventories are highly sensitive to surface erosion and runoff bypassing. Copyright (C) 2000 John Wiley and Sons, Ltd.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Earth Surface Processes and Landforms","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1002/1096-9837(200008)25:9<939::AID-ESP108>3.0.CO;2-0","issn":"01979337","usgsCitation":"Stanford, S., Seidl, M., and Ashley, G., 2000, Exposure age and erosional history of an upland planation surface in the US Atlantic Piedmont: Earth Surface Processes and Landforms, v. 25, no. 9, p. 939-950, https://doi.org/10.1002/1096-9837(200008)25:9<939::AID-ESP108>3.0.CO;2-0.","startPage":"939","endPage":"950","numberOfPages":"12","costCenters":[],"links":[{"id":206728,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1002/1096-9837(200008)25:9<939::AID-ESP108>3.0.CO;2-0"},{"id":230643,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0e2de4b0c8380cd5332e","contributors":{"authors":[{"text":"Stanford, S.D.","contributorId":79932,"corporation":false,"usgs":true,"family":"Stanford","given":"S.D.","email":"","affiliations":[],"preferred":false,"id":393404,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Seidl, M.A.","contributorId":84532,"corporation":false,"usgs":true,"family":"Seidl","given":"M.A.","email":"","affiliations":[],"preferred":false,"id":393405,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ashley, G.M.","contributorId":99313,"corporation":false,"usgs":true,"family":"Ashley","given":"G.M.","email":"","affiliations":[],"preferred":false,"id":393406,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022367,"text":"70022367 - 2000 - Sexing adult black-legged kittiwakes by DNA, behavior, and morphology","interactions":[],"lastModifiedDate":"2020-11-04T16:52:03.911135","indexId":"70022367","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3731,"text":"Waterbirds","onlineIssn":"19385390","printIssn":"15244695","active":true,"publicationSubtype":{"id":10}},"title":"Sexing adult black-legged kittiwakes by DNA, behavior, and morphology","docAbstract":"<p>We sexed adult Black-legged Kittiwakes (<i>Rissa tridactyla</i>) using DNA-based genetic techniques, behavior and morphology and compared results from these techniques. Genetic and morphology data were collected on 605 breeding kittiwakes and sex-specific behaviors were recorded for a sub-sample of 285 of these individuals. We compared sex classification based on both genetic and behavioral techniques for this sub-sample to assess the accuracy of the genetic technique. DNA-based techniques correctly sexed 97.2% and sex-specific behaviors, 96.5% of this sub-sample. We used the corrected genetic classifications from this sub-sample and the genetic classifications for the remaining birds, under the assumption they were correct, to develop predictive morphometric discriminant function models for all 605 birds. These models accurately predicted the sex of 73-96% of individuals examined, depending on the sample of birds used and the characters included. The most accurate single measurement for determining sex was length of head plus bill, which correctly classified 88% of individuals tested. When both members of a pair were measured, classification levels improved and approached the accuracy of both behavioral observations and genetic analyses. Morphometric techniques were only slightly less accurate than genetic techniques but were easier to implement in the field and less costly. Behavioral observations, while highly accurate, required that birds be easily observable during the breeding season and that birds be identifiable. As such, sex-specific behaviors may best be applied as a confirmation of sex for previously marked birds. All three techniques thus have the potential to be highly accurate, and the selection of one or more will depend on the circumstances of any particular field study.</p>","language":"English","publisher":"Waterbird Society","doi":"10.2307/1522177","usgsCitation":"Jodice, P., Lanctot, R., Gill, V., Roby, D., and Hatch, S.A., 2000, Sexing adult black-legged kittiwakes by DNA, behavior, and morphology: Waterbirds, v. 23, no. 3, p. 405-415, https://doi.org/10.2307/1522177.","productDescription":"11 p.","startPage":"405","endPage":"415","costCenters":[{"id":116,"text":"Alaska Science Center Biology MFEB","active":true,"usgs":true}],"links":[{"id":230642,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Alaska","otherGeospatial":"Middleton Island","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -146.45393371582028,\n              59.38463276428672\n            ],\n            [\n              -146.22596740722656,\n              59.38463276428672\n            ],\n            [\n              -146.22596740722656,\n              59.48763434062946\n            ],\n            [\n              -146.45393371582028,\n              59.48763434062946\n            ],\n            [\n              -146.45393371582028,\n              59.38463276428672\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"23","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8db5e4b08c986b3184fa","contributors":{"authors":[{"text":"Jodice, P.G.R.","contributorId":79846,"corporation":false,"usgs":true,"family":"Jodice","given":"P.G.R.","email":"","affiliations":[],"preferred":false,"id":393403,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lanctot, Richard B.","contributorId":77879,"corporation":false,"usgs":false,"family":"Lanctot","given":"Richard B.","affiliations":[{"id":6987,"text":"U.S. Fish and Wildlife Sevice","active":true,"usgs":false}],"preferred":false,"id":393402,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gill, V.A.","contributorId":35498,"corporation":false,"usgs":true,"family":"Gill","given":"V.A.","email":"","affiliations":[],"preferred":false,"id":393399,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Roby, D.D. 0000-0001-9844-0992","orcid":"https://orcid.org/0000-0001-9844-0992","contributorId":70944,"corporation":false,"usgs":true,"family":"Roby","given":"D.D.","affiliations":[],"preferred":false,"id":393401,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Hatch, Scott A. 0000-0002-0064-8187 shatch@usgs.gov","orcid":"https://orcid.org/0000-0002-0064-8187","contributorId":2625,"corporation":false,"usgs":true,"family":"Hatch","given":"Scott","email":"shatch@usgs.gov","middleInitial":"A.","affiliations":[{"id":116,"text":"Alaska Science Center Biology MFEB","active":true,"usgs":true}],"preferred":true,"id":393400,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}}
,{"id":70022366,"text":"70022366 - 2000 - Evaluation of ground-penetrating radar to detect free-phase hydrocarbons in fractured rocks: Results of numerical modeling and physical experiments","interactions":[],"lastModifiedDate":"2019-10-15T11:19:43","indexId":"70022366","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"Evaluation of ground-penetrating radar to detect free-phase hydrocarbons in fractured rocks: Results of numerical modeling and physical experiments","docAbstract":"The suitability of common-offset ground-penetrating radar (GPR) to detect free-phase hydrocarbons in bedrock fractures was evaluated using numerical modeling and physical experiments. The results of one- and two-dimensional numerical modeling at 100 megahertz indicate that GPR reflection amplitudes are relatively insensitive to fracture apertures ranging from 1 to 4 mm. The numerical modeling and physical experiments indicate that differences in the fluids that fill fractures significantly affect the amplitude and the polarity of electromagnetic waves reflected by subhorizontal fractures. Air-filled and hydrocarbon-filled fractures generate low-amplitude reflections that are in-phase with the transmitted pulse. Water-filled fractures create reflections with greater amplitude and opposite polarity than those reflections created by air-filled or hydrocarbon-filled fractures. The results from the numerical modeling and physical experiments demonstrate it is possible to distinguish water-filled fracture reflections from air- or hydrocarbon-filled fracture reflections, nevertheless subsurface heterogeneity, antenna coupling changes, and other sources of noise will likely make it difficult to observe these changes in GPR field data. This indicates that the routine application of common-offset GPR reflection methods for detection of hydrocarbon-filled fractures will be problematic. Ideal cases will require appropriately processed, high-quality GPR data, ground-truth information, and detailed knowledge of subsurface physical properties. Conversely, the sensitivity of GPR methods to changes in subsurface physical properties as demonstrated by the numerical and experimental results suggests the potential of using GPR methods as a monitoring tool. GPR methods may be suited for monitoring pumping and tracer tests, changes in site hydrologic conditions, and remediation activities.The suitability of common-offset ground-penetrating radar (GPR) to detect free-phase hydrocarbons in bedrock fractures was evaluated using numerical modeling and physical experiments. The results of one- and two-dimensional numerical modeling at 100 megahertz indicate that GPR reflection amplitudes are relatively insensitive to fracture apertures ranging from 1 to 4 mm. The numerical modeling and physical experiments indicate that differences in the fluids that fill fractures significantly affect the amplitude and the polarity of electromagnetic waves reflected by subhorizontal fractures. Air-filled and hydrocarbon-filled fractures generate low-amplitude reflections that are in-phase with the transmitted pulse. Water-filled fractures create reflections with greater amplitude and opposite polarity than those reflections created by air-filled or hydrocarbon-filled fractures. The results from the numerical modeling and physical experiments demonstrate it is possible to distinguish water-filled fracture reflections from air- or hydrocarbon-filled fracture reflections, nevertheless subsurface heterogeneity, antenna coupling changes, and other sources of noise will likely make it difficult to observe these changes in GPR field data. This indicates that the routine application of common-offset GPR reflection methods for detection of hydrocarbon-filled fractures will be problematic. Ideal cases will require appropriately processed, high-quality GPR data, ground-truth information, and detailed knowledge of subsurface physical properties. Conversely, the sensitivity of GPR methods to changes in subsurface physical properties as demonstrated by the numerical and experimental results suggests the potential of using GPR methods as a monitoring tool. GPR methods may be suited for monitoring pumping and tracer tests, changes in site hydrologic conditions, and remediation activities.","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.2000.tb00693.x","issn":"0017467X","usgsCitation":"Lane, J., Buursink, M., Haeni, F., and Versteeg, R., 2000, Evaluation of ground-penetrating radar to detect free-phase hydrocarbons in fractured rocks: Results of numerical modeling and physical experiments: Ground Water, v. 38, no. 6, p. 929-938, https://doi.org/10.1111/j.1745-6584.2000.tb00693.x.","productDescription":"10 p.","startPage":"929","endPage":"938","costCenters":[{"id":493,"text":"Office of Ground Water","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230608,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"38","issue":"6","noUsgsAuthors":false,"publicationDate":"2005-08-04","publicationStatus":"PW","scienceBaseUri":"505a0c80e4b0c8380cd52b94","contributors":{"authors":[{"text":"Lane, J.W. Jr.","contributorId":66723,"corporation":false,"usgs":true,"family":"Lane","given":"J.W.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":393395,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Buursink, M. L. 0000-0001-6491-386X","orcid":"https://orcid.org/0000-0001-6491-386X","contributorId":73658,"corporation":false,"usgs":true,"family":"Buursink","given":"M. L.","affiliations":[],"preferred":false,"id":393396,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Haeni, F.P.","contributorId":87105,"corporation":false,"usgs":true,"family":"Haeni","given":"F.P.","affiliations":[],"preferred":false,"id":393398,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Versteeg, R.J.","contributorId":74159,"corporation":false,"usgs":true,"family":"Versteeg","given":"R.J.","email":"","affiliations":[],"preferred":false,"id":393397,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70022363,"text":"70022363 - 2000 - Influence of acid volatile sulfides and metal concentrations on metal partitioning in contaminated sediments","interactions":[],"lastModifiedDate":"2020-09-02T19:28:14.15264","indexId":"70022363","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","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":"Influence of acid volatile sulfides and metal concentrations on metal partitioning in contaminated sediments","docAbstract":"<div class=\"hlFld-Abstract\"><div id=\"abstractBox\"><p class=\"articleBody_abstractText\">The influence of acid volatile sulfide (AVS) on the partitioning of Cd, Ni, and Zn in porewater (PW) and sediment as reactive metals (SEM, simultaneously extracted metals) was investigated in laboratory microcosms. Two spiking procedures were compared, and the effects of vertical geochemical gradients and infaunal activity were evaluated. Sediments were spiked with a Cd−Ni−Zn mixture (0.06, 3, 7.5 μmol/g, respectively) containing four levels of AVS (0.5, 7.5, 15, 35 μmol/g). The results were compared to sediments spiked with four levels of Cd−Ni−Zn mixtures at one AVS concentration (7.5 μmol/g). A vertical redox gradient was generated in each treatment by an 18-d incubation with an oxidized water column. [AVS] in the surface sediments decreased by 65−95% due to oxidation during incubation; initial [AVS] was maintained at 0.5−7.5 cm depth. PW metal concentrations were correlated with [SEM − AVS] among all data. But PW metal concentrations were variable, causing the distribution coefficient, Kd<sub>pw</sub><span>&nbsp;</span>(the ratio of [SEM] to PW metal concentrations) to vary by 2−3 orders of magnitude at a given [SEM − AVS]. One reason for the variability was that vertical profiles in PW metal concentrations appeared to be influenced by diffusion as well as [SEM − AVS]. The presence of animals appeared to enhance the diffusion of at least Zn. The generalization that PW metal concentrations are controlled by [SEM − AVS] is subject to some important qualifications if vertical gradients are complicated, metal concentrations vary, or equilibration times differ.</p></div></div>","language":"English","publisher":"ACS","doi":"10.1021/es001034+","issn":"0013936X","usgsCitation":"Lee, J., Lee, B., Luoma, S., Choi, H., Koh, C., and Brown, C.L., 2000, Influence of acid volatile sulfides and metal concentrations on metal partitioning in contaminated sediments: Environmental Science & Technology, v. 34, no. 21, p. 4511-4516, https://doi.org/10.1021/es001034+.","productDescription":"6 p.","startPage":"4511","endPage":"4516","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230534,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"34","issue":"21","noUsgsAuthors":false,"publicationDate":"2000-09-16","publicationStatus":"PW","scienceBaseUri":"505a3b0be4b0c8380cd621a9","contributors":{"authors":[{"text":"Lee, J.-S.","contributorId":15787,"corporation":false,"usgs":true,"family":"Lee","given":"J.-S.","email":"","affiliations":[],"preferred":false,"id":393383,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lee, B.-G.","contributorId":11777,"corporation":false,"usgs":true,"family":"Lee","given":"B.-G.","email":"","affiliations":[],"preferred":false,"id":393382,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Luoma, S. N.","contributorId":86353,"corporation":false,"usgs":true,"family":"Luoma","given":"S. N.","affiliations":[],"preferred":false,"id":393385,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Choi, H.J.","contributorId":105466,"corporation":false,"usgs":true,"family":"Choi","given":"H.J.","email":"","affiliations":[],"preferred":false,"id":393386,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Koh, C.-H.","contributorId":9797,"corporation":false,"usgs":true,"family":"Koh","given":"C.-H.","email":"","affiliations":[],"preferred":false,"id":393381,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Brown, C. L.","contributorId":35678,"corporation":false,"usgs":true,"family":"Brown","given":"C.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":393384,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}}
,{"id":70022362,"text":"70022362 - 2000 - Magma mixing, recharge and eruption histories recorded in plagioclase phenocrysts from El Chichón Volcano, Mexico","interactions":[],"lastModifiedDate":"2022-08-30T15:23:08.860778","indexId":"70022362","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2420,"text":"Journal of Petrology","active":true,"publicationSubtype":{"id":10}},"title":"Magma mixing, recharge and eruption histories recorded in plagioclase phenocrysts from El Chichón Volcano, Mexico","docAbstract":"<p class=\"chapter-para\">Consistent core-to-rim decreases of<span>&nbsp;</span><sup><i>87</i></sup>Sr/<sup><i>86</i></sup>Sr ratios and coincident increases in Sr concentrations in plagioclase phenocrysts of varying size (∼1 cm to 2 mm) are reported from samples of the 1982 and pre-1982 (∼200 ka) eruptions of El Chichón Volcano. Maximum<span>&nbsp;</span><sup><i>87</i></sup>Sr/<sup><i>86</i></sup>Sr ratios of ∼0·7054, significantly higher than the whole-rock isotopic ratios (∼0·7040–0·7045), are found in the cores of plagioclase phenocrysts, and minimum<span>&nbsp;</span><sup><i>87</i></sup>Sr/<sup><i>86</i></sup>Sr ratios of ∼0·7039 are found near some of the rims. Plagioclase phenocrysts commonly display abrupt fluctuations in An content (up to 25 mol %) that correspond to well-developed dissolution surfaces. The isotopic, textural and compositional characteristics suggest that these plagioclase phenocrysts grew in a system that was periodically recharged by higher-temperature magma with a lower<span>&nbsp;</span><sup><i>87</i></sup>Sr/<sup><i>86</i></sup>Sr ratio and a higher Sr concentration. Rim<span>&nbsp;</span><sup><i>87</i></sup>Sr/<sup><i>86</i></sup>Sr ratios in plagioclase phenocrysts of rocks from the 200 ka eruption indicate that, at that time, the magma had already attained the lowest recorded<span>&nbsp;</span><sup><i>87</i></sup>Sr/<sup><i>86</i></sup>Sr value of the system (∼0·7039). In contrast, cores from plagioclase phenocrysts of the 1982 eruption, inferred to have grown in the past few thousand years, have the highest recorded<span>&nbsp;</span><sup><i>87</i></sup>Sr/<sup><i>86</i></sup>Sr ratios of the system. Collectively, the Sr isotopic data (for plagioclase and whole rock), disequilibrium textural features of the phenocrysts, known eruption frequencies, and inferred crystal-residence times of the plagioclases are best interpreted in terms of an intermittent magma chamber model. Similar processes, including crustal contamination, magma mixing, periodic recharge by addition of more mafic magma to induce plagioclase disequilibrium (possibly triggering eruption) and subsequent re-equilibration, apparently were operative throughout the 200 ky history of the El Chichón magma system.</p>","largerWorkTitle":"Journal of Petrology","language":"English","publisher":"Oxford University Press","doi":"10.1093/petrology/41.9.1397","issn":"00223530","usgsCitation":"Tepley, F.J., Davidson, J., Tilling, R., and Arth, J.G., 2000, Magma mixing, recharge and eruption histories recorded in plagioclase phenocrysts from El Chichón Volcano, Mexico: Journal of Petrology, v. 41, no. 9, p. 1397-1411, https://doi.org/10.1093/petrology/41.9.1397.","productDescription":"15 p.","startPage":"1397","endPage":"1411","costCenters":[],"links":[{"id":479229,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1093/petrology/41.9.1397","text":"Publisher Index Page"},{"id":230495,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Mexico","state":"Chiapas","otherGeospatial":"El Chichón Volcano","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -93.23036670684814,\n              17.353833430489928\n            ],\n            [\n              -93.22813510894775,\n              17.354038239773242\n            ],\n            [\n              -93.2256031036377,\n              17.355430936832377\n            ],\n            [\n              -93.22367191314697,\n              17.35780668975055\n            ],\n            [\n              -93.22251319885252,\n              17.360428174478056\n            ],\n            [\n              -93.22148323059082,\n              17.361370261393365\n            ],\n            [\n              -93.22182655334473,\n              17.363582098596133\n            ],\n            [\n              -93.22508811950684,\n              17.366244459818855\n            ],\n            [\n              -93.22628974914551,\n              17.367882816726542\n            ],\n            [\n              -93.22792053222656,\n              17.367063640104178\n            ],\n            [\n              -93.23319911956787,\n              17.36632637801222\n            ],\n            [\n              -93.23654651641846,\n              17.3630905815249\n            ],\n            [\n              -93.23736190795898,\n              17.358257260106353\n            ],\n            [\n              -93.23401451110838,\n              17.35534901376882\n            ],\n            [\n              -93.23036670684814,\n              17.353833430489928\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"41","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a4b3ce4b0c8380cd693a5","contributors":{"authors":[{"text":"Tepley, F. J. III","contributorId":99723,"corporation":false,"usgs":true,"family":"Tepley","given":"F.","suffix":"III","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":393379,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Davidson, J.P.","contributorId":16123,"corporation":false,"usgs":true,"family":"Davidson","given":"J.P.","email":"","affiliations":[],"preferred":false,"id":393377,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Tilling, R.I. 0000-0003-4263-7221","orcid":"https://orcid.org/0000-0003-4263-7221","contributorId":98311,"corporation":false,"usgs":true,"family":"Tilling","given":"R.I.","affiliations":[],"preferred":false,"id":393378,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Arth, Joseph G.","contributorId":104546,"corporation":false,"usgs":true,"family":"Arth","given":"Joseph","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":393380,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70022361,"text":"70022361 - 2000 - Correlation of offshore seismic profiles with onshore New Jersey Miocene sediments","interactions":[],"lastModifiedDate":"2012-03-12T17:19:42","indexId":"70022361","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Correlation of offshore seismic profiles with onshore New Jersey Miocene sediments","docAbstract":"The New Jersey passive continental margin records the interaction of sequences and sea-level, although previous studies linking seismically defined sequences, borehole control, and global ??18O records were hindered by a seismic data gap on the inner-shelf. We describe new seismic data from the innermost New Jersey shelf that tie offshore seismic stratigraphy directly to onshore boreholes. These data link the onshore boreholes to existing seismic grids across the outer margin and to boreholes on the continental slope. Surfaces defined by age; facies, and log signature in the onshore boreholes at the base of sequences Kw2b, Kw2a, Kw1c, and Kw0 are now tied to seismic sequence boundaries m5s, m5.2s, m5.4s, and m6s, respectively, defined beneath the inner shelf. Sequence boundaries recognized in onshore boreholes and inner shelf seismic profiles apparently correlate with reflections m5, m5.2, m5.4, and m6, respectively, that were dated at slope boreholes during ODP Leg 150. We now recognize an additional sequence boundary beneath the shelf that we name m5.5s and correlate to the base of the onshore sequence Kw1b. The new seismic data image prograding Oligocene clinoforms beneath the inner shelf, consistent with the results from onshore boreholes. A land-based seismic profile crossing the Island Beach borehole reveals reflector geometries that we tie to Lower Miocene litho- and bio-facies in this borehole. These land-based seismic profiles image well-defined sequence boundaries, onlap and downlap truncations that correlate to Transgressive Systems Tracts (TST) and Highstand Systems Tracts (HST) identified in boreholes. Preliminary analysis of CH0698 data continues these system tract delineations across the inner shelf The CH0698 seismic profiles tie seismically defined sequence boundaries with sequences identified by lithiologic and paleontologic criteria. Both can now be related to global ??18O increases and attendant glacioeustatic lowerings. This integration of core, log, and seismic character of mid-Tertiary sediments across the width of the New Jersey margin is a major step in the long-standing effort to evaluate the impact of glaciouestasy on siliciclastic sediments of a passive continental margin. (C) 2000 Elsevier Science B.V. All rights reserved.","largerWorkTitle":"Sedimentary Geology","language":"English","doi":"10.1016/S0037-0738(00)00016-6","issn":"00370738","usgsCitation":"Monteverde, D., Miller, K., and Mountain, G.S., 2000, Correlation of offshore seismic profiles with onshore New Jersey Miocene sediments, <i>in</i> Sedimentary Geology, v. 134, no. 1-2, p. 111-127, https://doi.org/10.1016/S0037-0738(00)00016-6.","startPage":"111","endPage":"127","numberOfPages":"17","costCenters":[],"links":[{"id":206663,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0037-0738(00)00016-6"},{"id":230494,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"134","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fc3ee4b0c8380cd4e1c2","contributors":{"authors":[{"text":"Monteverde, D.H.","contributorId":67171,"corporation":false,"usgs":true,"family":"Monteverde","given":"D.H.","email":"","affiliations":[],"preferred":false,"id":393376,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Miller, K.G.","contributorId":18094,"corporation":false,"usgs":true,"family":"Miller","given":"K.G.","email":"","affiliations":[],"preferred":false,"id":393374,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mountain, Gregory S.","contributorId":29154,"corporation":false,"usgs":true,"family":"Mountain","given":"Gregory","email":"","middleInitial":"S.","affiliations":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":false,"id":393375,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022360,"text":"70022360 - 2000 - Alachlor transformation patterns in aquatic field mesocosms under variable oxygen and nutrient conditions","interactions":[],"lastModifiedDate":"2012-03-12T17:19:42","indexId":"70022360","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3716,"text":"Water Research","onlineIssn":"1879-2448","printIssn":"0043-1354","active":true,"publicationSubtype":{"id":10}},"title":"Alachlor transformation patterns in aquatic field mesocosms under variable oxygen and nutrient conditions","docAbstract":"Alachlor is one of the most commonly used herbicides in both Europe and North America. Because of its toxic properties, its fate and attenuation in natural waters is practically important. This paper assesses factors that affect alachlor decay rate in aquatic systems using field-scale experimental units. In particular, we used field mesocosms (11.3 m3 outdoor fiberglass tanks) to examine the affect of oxygen level and other factors on decay rate in water columns. This is one of the first studies ever performed where diverse water column conditions have been successfully simulated using common mesocosm-scale facilities. Four treatments were assessed, including aerobic systems (aerobic); low nutrient, oxygen-stratified systems (stratified-LN); moderate nutrient, oxygen-stratified systems (stratified-HN); and anaerobic systems (anaerobic). The lowest half-lives were observed in the anaerobic units (9.7 days) followed by the aerobic (21 days), stratified-HN (22 days), and stratified-LN (46 days) units. Our results indicate that alachlor is transformed most rapidly under anaerobic conditions, although the ambient phosphorus level also appears to influence decay rate. In this study, two common alachlor breakdown products, ethane sulfonic acid (ESA) and oxanilic acid, were also monitored. Oxanilic acid was produced in greater quantities than ESA under all treatments with the highest levels being produced in the stratified-HN units. In general, our results suggest that previous laboratory data, which indicated that high rates of alachlor decay can occur under oxygen-free methanogenic conditions, is translatable to field-scale applications. Copyright (C) 2000 Elsevier Science Ltd.Alachlor is one of the most commonly used herbicides in both Europe and North America. Because of its toxic properties, its fate and attenuation in natural waters is practically important. This paper assesses factors that affect alachlor decay rate in aquatic systems using field-scale experimental units. In particular, we used field mesocosms (11.3 m3 outdoor fiberglass tanks) to examine the affect of oxygen level and other factors on decay rate in water columns. This is one of the first studies ever performed where diverse water column conditions have been successfully simulated using common mesocosm-scale facilities. Four treatments were assessed, including aerobic systems (aerobic); low nutrient, oxygen-stratified systems (stratified-LN); moderate nutrient, oxygen-stratified systems (stratified-HN); and anaerobic systems (anaerobic). The lowest half-lives were observed in the anaerobic units (9.7 days) followed by the aerobic (21 days), stratified-HN (22 days), and stratified-LN (46 days) units. Our results indicate that alachlor is transformed most rapidly under anaerobic conditions, although the ambient phosphorus level also appears to influence decay rate. In this study, two common alachlor breakdown products, ethane sulfonic acid (ESA) and oxanilic acid, were also monitored. Oxanilic acid was produced in greater quantities than ESA under all treatments with the highest levels being produced in the stratified-HN units. In general, our results suggest that previous laboratory data, which indicated that high rates of alachlor decay can occur under oxygen-free methanogenic conditions, is translatable to field-scale applications.Aquatic field mesocosms were used to examine the influence of DO concentration and the presence of nutrients on alachlor transformation. Four treatments were used: wholly aerobic water columns, thermally and oxygen stratified water columns with low nutrient levels, stratified water columns with moderate nutrient levels, and wholly anaerobic water columns. The anaerobic treatment produced the highest rate of alachlor decay, followed by the aerobic and stratified treatments. The lowest decay rate occurred in the aerobic, low-nutrient stratified units.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Water Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier Science Ltd","publisherLocation":"Exeter, United Kingdom","doi":"10.1016/S0043-1354(00)00147-0","issn":"00431354","usgsCitation":"Graham, D., Miley, M., Denoyelles, F., Smith, V., Thurman, E., and Carter, R., 2000, Alachlor transformation patterns in aquatic field mesocosms under variable oxygen and nutrient conditions: Water Research, v. 34, no. 16, p. 4054-4062, https://doi.org/10.1016/S0043-1354(00)00147-0.","startPage":"4054","endPage":"4062","numberOfPages":"9","costCenters":[],"links":[{"id":206648,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0043-1354(00)00147-0"},{"id":230456,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"34","issue":"16","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e92fe4b0c8380cd48145","contributors":{"authors":[{"text":"Graham, D.W.","contributorId":102223,"corporation":false,"usgs":true,"family":"Graham","given":"D.W.","email":"","affiliations":[],"preferred":false,"id":393372,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Miley, M.K.","contributorId":43939,"corporation":false,"usgs":true,"family":"Miley","given":"M.K.","email":"","affiliations":[],"preferred":false,"id":393369,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Denoyelles, F.","contributorId":96039,"corporation":false,"usgs":true,"family":"Denoyelles","given":"F.","affiliations":[],"preferred":false,"id":393371,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Smith, Val H.","contributorId":69317,"corporation":false,"usgs":false,"family":"Smith","given":"Val H.","affiliations":[],"preferred":false,"id":393370,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Thurman, E.M.","contributorId":102864,"corporation":false,"usgs":true,"family":"Thurman","given":"E.M.","affiliations":[],"preferred":false,"id":393373,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Carter, R.","contributorId":13397,"corporation":false,"usgs":true,"family":"Carter","given":"R.","affiliations":[],"preferred":false,"id":393368,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}}
,{"id":70022358,"text":"70022358 - 2000 - On the modified Mercalli intensities and magnitudes of the 1811-1812 New Madrid earthquakes","interactions":[],"lastModifiedDate":"2022-09-07T14:39:41.053663","indexId":"70022358","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","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":"On the modified Mercalli intensities and magnitudes of the 1811-1812 New Madrid earthquakes","docAbstract":"<p>We reexamine original felt reports from the 1811–1812 New Madrid earthquakes and determine revised isoseismal maps for the three principal mainshocks. In many cases we interpret lower values than those assigned by earlier studies. In some cases the revisions result from an interpretation of original felt reports with an appreciation for site response issues. Additionally, earlier studies had assigned modified Mercalli intensity (MMI) values of V-VII to a substantial number of reports that we conclude do not describe damage commensurate with intensities this high. We investigate several approaches to contouring the MMI values using both analytical and subjective methods. For the first mainshock on 02∶15 LT December 16, 1811, our preferred contouring yields <i>M</i>ω7.2–7.3 using the area-moment regressions of <i>Johnston</i> [1996]. For the 08∶00 LT on January 23, 1812, and 03∶45 LT on February 7, 1812, mainshocks, we obtain <i>M</i>ω7.0 and <i>M</i>ω7.4–7.5, respectively. Our magnitude for the February mainshock is consistent with the established geometry of the Reelfoot fault, which all evidence suggests to have been the causative structure for this event. We note that the inference of lower magnitudes for the New Madrid events implies that site response plays a significant role in controlling seismic hazard at alluvial sites in the central and eastern United States. We also note that our results suggest that thrusting may have been the dominant mechanism of faulting associated with the 1811–1812 sequence.</p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000JB900110","issn":"01480227","usgsCitation":"Hough, S., Armbruster, J., Seeber, L., and Hough, J., 2000, On the modified Mercalli intensities and magnitudes of the 1811-1812 New Madrid earthquakes: Journal of Geophysical Research B: Solid Earth, v. 105, no. B10, p. 23839-23864, https://doi.org/10.1029/2000JB900110.","productDescription":"26 p.","startPage":"23839","endPage":"23864","costCenters":[],"links":[{"id":479340,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2000jb900110","text":"Publisher Index Page"},{"id":230420,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arkansas, Illinois, Kentucky, Missouri, Tennessee","otherGeospatial":"Mississippi Valley, New Madrid Fault","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -91.16455078125,\n              35.02999636902566\n            ],\n            [\n              -88.06640625,\n              35.02999636902566\n            ],\n            [\n              -88.06640625,\n              37.75334401310656\n            ],\n            [\n              -91.16455078125,\n              37.75334401310656\n            ],\n            [\n              -91.16455078125,\n              35.02999636902566\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"105","issue":"B10","noUsgsAuthors":false,"publicationDate":"2000-10-10","publicationStatus":"PW","scienceBaseUri":"505a6ddde4b0c8380cd75378","contributors":{"authors":[{"text":"Hough, S. E. 0000-0002-5980-2986","orcid":"https://orcid.org/0000-0002-5980-2986","contributorId":7316,"corporation":false,"usgs":true,"family":"Hough","given":"S. E.","affiliations":[],"preferred":false,"id":393359,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Armbruster, J.G.","contributorId":71202,"corporation":false,"usgs":true,"family":"Armbruster","given":"J.G.","email":"","affiliations":[],"preferred":false,"id":393361,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Seeber, L.","contributorId":37329,"corporation":false,"usgs":true,"family":"Seeber","given":"L.","email":"","affiliations":[],"preferred":false,"id":393360,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hough, J.F.","contributorId":101276,"corporation":false,"usgs":true,"family":"Hough","given":"J.F.","email":"","affiliations":[],"preferred":false,"id":393362,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70022357,"text":"70022357 - 2000 - Pore fluid pressure, apparent friction, and Coulomb failure","interactions":[],"lastModifiedDate":"2013-12-03T15:53:47","indexId":"70022357","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","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":"Pore fluid pressure, apparent friction, and Coulomb failure","docAbstract":"Many recent studies of stress-triggered seismicity rely on a fault failure model with a single free parameter, the apparent coefficient of friction, presumed to be a material constant with possible values 0 ≤ μ′ ≤ 1. These studies may present a misleading view of fault strength and the role of pore fluid pressure in earthquake failure. The parameter μ′ is intended to incorporate the effects of both friction and pore pressure, but is a material constant only if changes in pore fluid pressure induced by changes in stress are proportional to the normal stress change across the potential failure plane. Although specific models of fault zones permit such a relation, neither is it known that fault zones within the Earth behave this way, nor is this behavior expected in all cases. In contrast, for an isotropic homogeneous poroelastic model the pore pressure changes are proportional to changes in mean stress, μ′ is not a material constant, and −∞ ≤ μ′ ≤ +∞. Analysis of the change in Coulomb failure stress for tectonically loaded reverse and strike-slip faults shows considerable differences between these two pore pressure models, suggesting that such models might be distinguished from one another using observations of triggered seismicity (e.g., aftershocks). We conclude that using the constant apparent friction model exclusively in studies of Coulomb failure stress is unwise and could lead to significant errors in estimated stress change and seismic hazard.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Geophysical Research B: Solid Earth","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1029/2000JB900119","issn":"01480227","usgsCitation":"Beeler, N., Simpson, R., Hickman, S., and Lockner, D., 2000, Pore fluid pressure, apparent friction, and Coulomb failure: Journal of Geophysical Research B: Solid Earth, v. 105, no. B11, p. 25533-25542, https://doi.org/10.1029/2000JB900119.","startPage":"25533","endPage":"25542","numberOfPages":"10","costCenters":[],"links":[{"id":230419,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":280170,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1029/2000JB900119"}],"volume":"105","issue":"B11","noUsgsAuthors":false,"publicationDate":"2000-11-10","publicationStatus":"PW","scienceBaseUri":"505a7dc9e4b0c8380cd7a163","contributors":{"authors":[{"text":"Beeler, N.M. 0000-0002-3397-8481","orcid":"https://orcid.org/0000-0002-3397-8481","contributorId":68894,"corporation":false,"usgs":true,"family":"Beeler","given":"N.M.","affiliations":[],"preferred":false,"id":393356,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Simpson, R.W.","contributorId":76738,"corporation":false,"usgs":true,"family":"Simpson","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":393357,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hickman, S.H. 0000-0003-2075-9615","orcid":"https://orcid.org/0000-0003-2075-9615","contributorId":16027,"corporation":false,"usgs":true,"family":"Hickman","given":"S.H.","affiliations":[],"preferred":false,"id":393355,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Lockner, D.A. 0000-0001-8630-6833","orcid":"https://orcid.org/0000-0001-8630-6833","contributorId":85603,"corporation":false,"usgs":true,"family":"Lockner","given":"D.A.","affiliations":[],"preferred":false,"id":393358,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70022356,"text":"70022356 - 2000 - Viscoelastic-coupling model for the earthquake cycle driven from below","interactions":[],"lastModifiedDate":"2022-09-07T14:31:07.12735","indexId":"70022356","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","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 for the earthquake cycle driven from below","docAbstract":"<p>In a linear system the earthquake cycle can be represented as the sum of a solution which reproduces the earthquake cycle itself (viscoelastic-coupling model) and a solution that provides the driving force. We consider two cases, one in which the earthquake cycle is driven by stresses transmitted along the schizosphere and a second in which the cycle is driven from below by stresses transmitted along the upper mantle (i.e., the schizosphere and upper mantle, respectively, act as stress guides in the lithosphere). In both cases the driving stress is attributed to steady motion of the stress guide, and the upper crust is assumed to be elastic. The surface deformation that accumulates during the interseismic interval depends solely upon the earthquake-cycle solution (viscoelastic-coupling model) not upon the driving source solution. Thus geodetic observations of interseismic deformation are insensitive to the source of the driving forces in a linear system. In particular, the suggestion of <i>Bourne et al</i>. [1998] that the deformation that accumulates across a transform fault system in the interseismic interval is a replica of the deformation that accumulates in the upper mantle during the same interval does not appear to be correct for linear systems.</p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000JB900276","issn":"01480227","usgsCitation":"Savage, J., 2000, Viscoelastic-coupling model for the earthquake cycle driven from below: Journal of Geophysical Research B: Solid Earth, v. 105, no. B11, p. 25525-25532, https://doi.org/10.1029/2000JB900276.","productDescription":"8 p.","startPage":"25525","endPage":"25532","costCenters":[],"links":[{"id":479165,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2000jb900276","text":"Publisher Index Page"},{"id":230378,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"105","issue":"B11","noUsgsAuthors":false,"publicationDate":"2000-11-10","publicationStatus":"PW","scienceBaseUri":"505bc285e4b08c986b32abbf","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":393354,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70022354,"text":"70022354 - 2000 - Bedrock knobs, San Francisco Bay: Do navigation hazards outweigh other environment problems?","interactions":[],"lastModifiedDate":"2022-06-16T15:12:03.305777","indexId":"70022354","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1574,"text":"Environmental & Engineering Geoscience","printIssn":"1078-7275","active":true,"publicationSubtype":{"id":10}},"title":"Bedrock knobs, San Francisco Bay: Do navigation hazards outweigh other environment problems?","docAbstract":"<p>Three bedrock knobs (Arch, Harding, and Shag rocks) rise above the unconsolidated sediment of central San Francisco Bay to a water depth of less than -12 m (&lt;-39.4 ft MLLW). These rocks are within the westbound vessel traffic area, and the northernmost, Harding Rock, is approximately 300 m (984 ft) from the two-way deep water traffic lane. The rocks pose a hazard to deep-draft vessels. Large ships with drafts deeper than -17 m (-55.8 ft) cross central San Francisco Bay bound for and returning from major port cities of the Bay estuary. Acoustic profiling data show that bedrock extends at a gentle to moderate slope away from the knobs. These data also show that two of the knobs, Harding and Shag, may be part of a bedrock ridge that extends to Alcatraz Island and perhaps southeast to Blossom Rock. The tops of these rocks should be lowered to a depth of -17 m (-55.8 ft), with a total volume of as much as 245,000 m<span>&nbsp;</span><sup>3</sup><span>&nbsp;</span>(320,460 yd<span>&nbsp;</span><sup>3</sup><span>&nbsp;</span>), at an estimated cost of nearly 27 million dollars, to eliminate the possibility that a tanker would strike one and rupture. A resulting large oil spill would likely cost many times more than the 10 million dollars needed to clean up a small 1996 spill. If the rocks were removed, local habitat for striped bass and other game fish would be altered, with potential negative impact on sport fishing. Currently, public officials are studying the benefits to the Bay environment of lowering the rock knobs.</p>","language":"English","publisher":"Geological Society of America","doi":"10.2113/gseegeosci.6.1.41","issn":"10787275","usgsCitation":"Carlson, P.R., Chin, J., and Wong, F.L., 2000, Bedrock knobs, San Francisco Bay: Do navigation hazards outweigh other environment problems?: Environmental & Engineering Geoscience, v. 6, no. 1, p. 41-55, https://doi.org/10.2113/gseegeosci.6.1.41.","productDescription":"15 p.","startPage":"41","endPage":"55","costCenters":[],"links":[{"id":230376,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","city":"San Francisco","otherGeospatial":"Alcatraz, Angel Island, Arch Rock, Blossom Rock, Harding Rock, San Francisco Bay, Shag Rock","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -122.51609802246092,\n              37.77885586164994\n            ],\n            [\n              -122.47970581054688,\n              37.785910776551354\n            ],\n            [\n              -122.47352600097658,\n              37.79784832917947\n            ],\n            [\n              -122.40966796874999,\n              37.80381638220768\n            ],\n            [\n              -122.39250183105467,\n              37.7745140408613\n            ],\n            [\n              -122.31834411621095,\n              37.801646236899785\n            ],\n            [\n              -122.28813171386719,\n              37.82768377181359\n            ],\n            [\n              -122.30186462402345,\n              37.89056989382214\n            ],\n            [\n              -122.32109069824219,\n              37.91224232115986\n            ],\n            [\n              -122.35198974609375,\n              37.92090950501414\n            ],\n            [\n              -122.39593505859376,\n              37.93444993515032\n            ],\n            [\n              -122.49000549316408,\n              37.940406934417254\n            ],\n            [\n              -122.51609802246092,\n              37.95231948449752\n            ],\n            [\n              -122.51335144042969,\n              37.91874280479498\n            ],\n            [\n              -122.48245239257812,\n              37.9079083462673\n            ],\n            [\n              -122.49343872070312,\n              37.899239630600185\n            ],\n            [\n              -122.53257751464842,\n              37.9079083462673\n            ],\n            [\n              -122.53257751464842,\n              37.88731847929118\n            ],\n            [\n              -122.48382568359374,\n              37.85045908105493\n            ],\n            [\n              -122.48794555664061,\n              37.83148014503288\n            ],\n            [\n              -122.53875732421875,\n              37.823344820392535\n            ],\n            [\n              -122.51609802246092,\n              37.77885586164994\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"6","issue":"1","noUsgsAuthors":false,"publicationDate":"2000-02-01","publicationStatus":"PW","scienceBaseUri":"5059f08ee4b0c8380cd4a7b0","contributors":{"authors":[{"text":"Carlson, Paul R.","contributorId":81469,"corporation":false,"usgs":true,"family":"Carlson","given":"Paul","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":393352,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chin, John L.","contributorId":98291,"corporation":false,"usgs":true,"family":"Chin","given":"John L.","affiliations":[],"preferred":false,"id":393350,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Wong, Florence L. 0000-0002-3918-5896 fwong@usgs.gov","orcid":"https://orcid.org/0000-0002-3918-5896","contributorId":1990,"corporation":false,"usgs":true,"family":"Wong","given":"Florence","email":"fwong@usgs.gov","middleInitial":"L.","affiliations":[{"id":520,"text":"Pacific Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":393351,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022353,"text":"70022353 - 2000 - Debris-flow hazards in the Blue Ridge of central Virginia","interactions":[],"lastModifiedDate":"2022-06-16T15:41:31.968178","indexId":"70022353","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1574,"text":"Environmental & Engineering Geoscience","printIssn":"1078-7275","active":true,"publicationSubtype":{"id":10}},"title":"Debris-flow hazards in the Blue Ridge of central Virginia","docAbstract":"<p>The June 27, 1995, storm in Madison County, Virginia produced debris flows and floods that devastated a small (130 km<span>&nbsp;</span><sup>2</sup><span>&nbsp;</span>) area of the Blue Ridge in the eastern United States. Although similar debris-flow inducing storm events may return only approximately once every two thousand years to the same given locale, these events affecting a similar small-sized area occur about every three years somewhere in the central and southern Appalachian Mountains. From physical examinations and mapping of debris-flow sources, paths, and deposits in Madison County, we develop methods for identifying areas subject to debris flows using Geographic Information Systems (GIS) technology. We examined the rainfall intensity and duration characteristics of the June 27, 1995, and other storms, in the Blue Ridge of central Virginia, and have defined a minimum threshold necessary to trigger debris flows in granitic rocks. In comparison with thresholds elsewhere, longer and more intense rainfall is necessary to trigger debris flows in the Blue Ridge.</p>","language":"English","publisher":"Geological Society of America","doi":"10.2113/gseegeosci.6.1.3","issn":"10787275","usgsCitation":"Wieczorek, G.F., Morgan, B., and Campbell, R.H., 2000, Debris-flow hazards in the Blue Ridge of central Virginia: Environmental & Engineering Geoscience, v. 6, no. 1, p. 3-23, https://doi.org/10.2113/gseegeosci.6.1.3.","productDescription":"21 p.","startPage":"3","endPage":"23","costCenters":[],"links":[{"id":230342,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Virginia","county":"Madison County","otherGeospatial":"Blue Ridge Mountains","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -79.29656982421875,\n              38.12159327165922\n            ],\n            [\n              -78.8543701171875,\n              37.98317483351337\n            ],\n            [\n              -78.4259033203125,\n              37.97451499202459\n            ],\n            [\n              -78.15399169921874,\n              37.903032319353656\n            ],\n            [\n              -77.6019287109375,\n              38.82473078093276\n            ],\n            [\n              -77.838134765625,\n              38.92309226598178\n            ],\n            [\n              -78.06884765624999,\n              38.95727304112803\n            ],\n            [\n              -78.5357666015625,\n              39.095962936305476\n            ],\n            [\n              -79.10430908203125,\n              38.48154475346391\n            ],\n            [\n              -79.29656982421875,\n              38.12159327165922\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"6","issue":"1","noUsgsAuthors":false,"publicationDate":"2000-02-01","publicationStatus":"PW","scienceBaseUri":"5059fdfbe4b0c8380cd4ea47","contributors":{"authors":[{"text":"Wieczorek, G. F.","contributorId":50143,"corporation":false,"usgs":true,"family":"Wieczorek","given":"G.","middleInitial":"F.","affiliations":[],"preferred":false,"id":393347,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Morgan, B. A.","contributorId":87128,"corporation":false,"usgs":true,"family":"Morgan","given":"B. A.","affiliations":[],"preferred":false,"id":393349,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Campbell, R. H.","contributorId":52160,"corporation":false,"usgs":true,"family":"Campbell","given":"R.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":393348,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
]}