The Nevada Test Site (NTS), in southern Nye County, Nevada, straddles significant pre-Tertiary structural and stratigraphic boundaries. Detailed stratigraphy and biostratigraphy of the Upper Paleozoic section delineates the regional trust sheets and constrains their burial histories. The Paleozoic rocks record three phases of contractional deformation, overprinted by strike-slip faulting. These occurred in the folloing order: (1) foreland-vergant folding and imbricate thrusting in the footwall of the Belted Range thrust; (2) hinterland-vergent folding and thrusting; and (3) north-vergant folding that we interpret as footwall deformation below a third major thrust system. Sinistral slip, typically accompanied by minor east-west shortening, has occurred along a series of north-northeast--north-northwest--striking faults around Yucca Flat. This strike-slip faulting postdates both foreland-vergent and hinterland-vergent deformation, and predates the Cretaceous Climax stock; its age relative to the north-vergent folding and thrusting is unknown. Our new understanding of the geometry of these structures provides new insights into the correlation and interpretation of regional structural features. Field trip stops will examine: (1) the stratigraphic differences that allow us to distinguish the regional thrust sheets and constrain their burial histories; and (2) the field relationships that document the kinematics and relative ages of the penetrative deformational events.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/0-8137-0002-7.337","usgsCitation":"Cashman, P.H., Cole, J., and Trexler, J.H., 2000, Superposed fold-thrust events at the Nevada Test Site: GSA Field Guides, v. 2, p. 337-354, https://doi.org/10.1130/0-8137-0002-7.337.","productDescription":"18 p.","startPage":"337","endPage":"354","numberOfPages":"18","costCenters":[{"id":318,"text":"Geosciences and Environmental Change Science Center","active":true,"usgs":true}],"links":[{"id":281200,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Nevada","county":"Nye County","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -117.5,36.0 ], [ -117.5,38.0 ], [ -115.0,38.0 ], [ -115.0,36.0 ], [ -117.5,36.0 ] ] ] } } ] }","volume":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd7563e4b0b2908510a344","contributors":{"authors":[{"text":"Cashman, Patricia H.","contributorId":84058,"corporation":false,"usgs":true,"family":"Cashman","given":"Patricia","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":488666,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cole, J. C.","contributorId":21539,"corporation":false,"usgs":true,"family":"Cole","given":"J. C.","affiliations":[],"preferred":false,"id":488664,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Trexler, James H. Jr.","contributorId":37399,"corporation":false,"usgs":true,"family":"Trexler","given":"James","suffix":"Jr.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":488665,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70068930,"text":"70068930 - 2000 - Nitrogen biogeochemistry and surface-subsurface exchange in streams","interactions":[],"lastModifiedDate":"2018-09-10T07:29:46","indexId":"70068930","displayToPublicDate":"2000-01-01T14:21:41","publicationYear":"2000","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"chapter":"8","title":"Nitrogen biogeochemistry and surface-subsurface exchange in streams","docAbstract":"No abstract available.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Streams and ground waters","largerWorkSubtype":{"id":4,"text":"Other Government Series"},"language":"English","publisher":"Academic Press","publisherLocation":"San Diego, CA","doi":"10.1016/B978-012389845-6/50009-0","usgsCitation":"Duff, J.H., and Triska, F.J., 2000, Nitrogen biogeochemistry and surface-subsurface exchange in streams, chap. 8 of Streams and ground waters, p. 197-220, https://doi.org/10.1016/B978-012389845-6/50009-0.","productDescription":"24 p.","startPage":"197","endPage":"220","costCenters":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":280908,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arizona;California;Colorado;Minnesota","otherGeospatial":"Little Lost Man Creek;Platte River;Shingobee River;Sycamore Creek","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -124.46,31.32 ], [ -124.46,49.41 ], [ -89.47,49.41 ], [ -89.47,31.32 ], [ -124.46,31.32 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd691ae4b0b290851027ce","contributors":{"editors":[{"text":"Jones, Jeremy B.","contributorId":113650,"corporation":false,"usgs":true,"family":"Jones","given":"Jeremy","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":509688,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"Mulholland, Patrick J.","contributorId":112634,"corporation":false,"usgs":false,"family":"Mulholland","given":"Patrick","email":"","middleInitial":"J.","affiliations":[{"id":32968,"text":"Oak Ridge National Laboratory, Oak Ridge, TN","active":true,"usgs":false}],"preferred":false,"id":509687,"contributorType":{"id":2,"text":"Editors"},"rank":2}],"authors":[{"text":"Duff, John H. jhduff@usgs.gov","contributorId":961,"corporation":false,"usgs":true,"family":"Duff","given":"John","email":"jhduff@usgs.gov","middleInitial":"H.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":488180,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Triska, Frank J.","contributorId":88781,"corporation":false,"usgs":true,"family":"Triska","given":"Frank","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":488181,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70073535,"text":"70073535 - 2000 - Regional versus floodplain perspectives on flood management in the Upper Mississippi River Basin","interactions":[],"lastModifiedDate":"2014-01-17T14:40:42","indexId":"70073535","displayToPublicDate":"2000-01-01T14:16:00","publicationYear":"2000","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Regional versus floodplain perspectives on flood management in the Upper Mississippi River Basin","docAbstract":"No abstract available.","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Selected studies on natural and human factors related to flood management in the Upper Mississippi River Basin","largerWorkSubtype":{"id":4,"text":"Other Government Series"},"language":"English","publisher":"U.S. Government Printing Office","usgsCitation":"Freeman, G.E., Frazier, A.G., and Kelmelis, J.A., 2000, Regional versus floodplain perspectives on flood management in the Upper Mississippi River Basin, chap. of Selected studies on natural and human factors related to flood management in the Upper Mississippi River Basin, v. 4, p. 1-3.","productDescription":"3 p.","startPage":"1","endPage":"3","numberOfPages":"3","costCenters":[],"links":[{"id":281255,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Illinois;Iowa;Minnesota;Missouri;Wisconsin","otherGeospatial":"Upper Mississippi River Basin","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -97.24,36.47 ], [ -97.24,49.38 ], [ -87.43,49.38 ], [ -87.43,36.47 ], [ -97.24,36.47 ] ] ] } } ] }","volume":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd7007e4b0b29085106c99","contributors":{"authors":[{"text":"Freeman, Gary E.","contributorId":10325,"corporation":false,"usgs":true,"family":"Freeman","given":"Gary","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":488903,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Frazier, Ann G.","contributorId":102789,"corporation":false,"usgs":true,"family":"Frazier","given":"Ann","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":488905,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kelmelis, John A.","contributorId":40893,"corporation":false,"usgs":true,"family":"Kelmelis","given":"John","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":488904,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70074108,"text":"70074108 - 2000 - Can contaminant transport models predict breakthrough?","interactions":[],"lastModifiedDate":"2018-12-14T06:42:02","indexId":"70074108","displayToPublicDate":"2000-01-01T14:15:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1866,"text":"Groundwater Monitoring & Remediation","active":true,"publicationSubtype":{"id":10}},"title":"Can contaminant transport models predict breakthrough?","docAbstract":"A solute breakthrough curve measured during a two-well tracer test was successfully predicted in 1986 using specialized contaminant transport models. Water was injected into a confined, unconsolidated sand aquifer and pumped out 125 feet (38.3 m) away at the same steady rate. The injected water was spiked with bromide for over three days; the outflow concentration was monitored for a month. Based on previous tests, the horizontal hydraulic conductivity of the thick aquifer varied by a factor of seven among 12 layers. Assuming stratified flow with small dispersivities, two research groups accurately predicted breakthrough with three-dimensional (12-layer) models using curvilinear elements following the arc-shaped flowlines in this test.\n\nCan contaminant transport models commonly used in industry, that use rectangular blocks, also reproduce this breakthrough curve? The two-well test was simulated with four MODFLOW-based models, MT3D (FD and HMOC options), MODFLOWT, MOC3D, and MODFLOW-SURFACT.\n\nUsing the same 12 layers and small dispersivity used in the successful 1986 simulations, these models fit almost as accurately as the models using curvilinear blocks. Subtle variations in the curves illustrate differences among the codes. Sensitivities of the results to number and size of grid blocks, number of layers, boundary conditions, and values of dispersivity and porosity are briefly presented. The fit between calculated and measured breakthrough curves degenerated as the number of layers and/or grid blocks decreased, reflecting a loss of model predictive power as the level of characterization lessened. Therefore, the breakthrough curve for most field sites can be predicted only qualitatively due to limited characterization of the hydrogeology and contaminant source strength.","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6592.2000.tb00295.x","usgsCitation":"Peng, W., Hampton, D.R., Konikow, L.F., Kambham, K., and Benegar, J.J., 2000, Can contaminant transport models predict breakthrough?: Groundwater Monitoring & Remediation, v. 20, no. 4, p. 104-113, https://doi.org/10.1111/j.1745-6592.2000.tb00295.x.","productDescription":"10 p.","startPage":"104","endPage":"113","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":281587,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":281586,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1745-6592.2000.tb00295.x"}],"country":"United States","state":"Alabama","city":"Mobile","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -88.221253,30.560374 ], [ -88.221253,30.843458 ], [ -87.956616,30.843458 ], [ -87.956616,30.560374 ], [ -88.221253,30.560374 ] ] ] } } ] }","volume":"20","issue":"4","noUsgsAuthors":false,"publicationDate":"2007-02-22","publicationStatus":"PW","scienceBaseUri":"53cd501de4b0b290850f3217","contributors":{"authors":[{"text":"Peng, Wei-Shyuan","contributorId":108389,"corporation":false,"usgs":true,"family":"Peng","given":"Wei-Shyuan","email":"","affiliations":[],"preferred":false,"id":489415,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hampton, Duane R.","contributorId":65377,"corporation":false,"usgs":true,"family":"Hampton","given":"Duane","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":489413,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Konikow, Leonard F. 0000-0002-0940-3856 lkonikow@usgs.gov","orcid":"https://orcid.org/0000-0002-0940-3856","contributorId":158,"corporation":false,"usgs":true,"family":"Konikow","given":"Leonard","email":"lkonikow@usgs.gov","middleInitial":"F.","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":489411,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Kambham, Kiran","contributorId":100284,"corporation":false,"usgs":true,"family":"Kambham","given":"Kiran","email":"","affiliations":[],"preferred":false,"id":489414,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Benegar, Jeffery J.","contributorId":8760,"corporation":false,"usgs":true,"family":"Benegar","given":"Jeffery","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":489412,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70073657,"text":"70073657 - 2000 - Remote sensing for site characterization","interactions":[],"lastModifiedDate":"2014-01-20T14:18:36","indexId":"70073657","displayToPublicDate":"2000-01-01T14:10:00","publicationYear":"2000","noYear":false,"publicationType":{"id":4,"text":"Book"},"title":"Remote sensing for site characterization","docAbstract":"This volume, Remote Sensing for Site Characterization, describes the feasibility of aircraft- and satellite-based methods of revealing environmental-geological problems. A balanced ratio between explanations of the methodological/technical side and presentations of case studies is maintained. The comparison of case studies from North America and Germany show how the respective territorial conditions lead to distinct methodological approaches.","largerWorkTitle":"Methods in environmental geology","language":"English","publisher":"Springer","publisherLocation":"Berlin","usgsCitation":"Kuehn, F., King, T.V., Hoerig, B., and Peters, D.C., 2000, Remote sensing for site characterization, 211 p.","productDescription":"211 p.","numberOfPages":"211","costCenters":[],"links":[{"id":281294,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Canada;Germany;United States","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ 173.0,16.916667 ], [ 173.0,83.3 ], [ 5.87,83.3 ], [ 5.87,16.916667 ], [ 173.0,16.916667 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd7049e4b0b29085106f40","contributors":{"editors":[{"text":"Kuehn, Friedrich","contributorId":66595,"corporation":false,"usgs":true,"family":"Kuehn","given":"Friedrich","email":"","affiliations":[],"preferred":false,"id":509740,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"King, Trude V.","contributorId":16314,"corporation":false,"usgs":true,"family":"King","given":"Trude","email":"","middleInitial":"V.","affiliations":[],"preferred":false,"id":509739,"contributorType":{"id":2,"text":"Editors"},"rank":2},{"text":"Hoerig, Bernhard","contributorId":95386,"corporation":false,"usgs":true,"family":"Hoerig","given":"Bernhard","email":"","affiliations":[],"preferred":false,"id":509741,"contributorType":{"id":2,"text":"Editors"},"rank":3},{"text":"Peters, Douglas C.","contributorId":106797,"corporation":false,"usgs":true,"family":"Peters","given":"Douglas","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":509742,"contributorType":{"id":2,"text":"Editors"},"rank":4}],"authors":[{"text":"Kuehn, Friedrich","contributorId":66595,"corporation":false,"usgs":true,"family":"Kuehn","given":"Friedrich","email":"","affiliations":[],"preferred":false,"id":488984,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"King, Trude V.","contributorId":16314,"corporation":false,"usgs":true,"family":"King","given":"Trude","email":"","middleInitial":"V.","affiliations":[],"preferred":false,"id":488983,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hoerig, Bernhard","contributorId":95386,"corporation":false,"usgs":true,"family":"Hoerig","given":"Bernhard","email":"","affiliations":[],"preferred":false,"id":488985,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Peters, Douglas C.","contributorId":106797,"corporation":false,"usgs":true,"family":"Peters","given":"Douglas","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":488986,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70073531,"text":"70073531 - 2000 - Selected studies on natural and human factors related to flood management in the Upper Mississippi River Basin","interactions":[],"lastModifiedDate":"2014-01-17T14:40:05","indexId":"70073531","displayToPublicDate":"2000-01-01T14:09:00","publicationYear":"2000","noYear":false,"publicationType":{"id":4,"text":"Book"},"title":"Selected studies on natural and human factors related to flood management in the Upper Mississippi River Basin","docAbstract":"No abstract available.","largerWorkTitle":"Science for floodplain management into the 21st century","language":"English","publisher":"U.S. Government Printing Office","usgsCitation":"Frazier, A.G., and Freeman, G.E., 2000, Selected studies on natural and human factors related to flood management in the Upper Mississippi River Basin, v. 4, 201 p.","productDescription":"201 p.","numberOfPages":"201","costCenters":[],"links":[{"id":281254,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Illinois;Iowa;Minnesota;Missouri;Wisconsin","otherGeospatial":"Upper Mississippi River Basin","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -97.24,36.47 ], [ -97.24,49.38 ], [ -87.43,49.38 ], [ -87.43,36.47 ], [ -97.24,36.47 ] ] ] } } ] }","volume":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd724de4b0b2908510838e","contributors":{"authors":[{"text":"Frazier, Ann G.","contributorId":102789,"corporation":false,"usgs":true,"family":"Frazier","given":"Ann","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":488902,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Freeman, Gary E.","contributorId":10325,"corporation":false,"usgs":true,"family":"Freeman","given":"Gary","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":488901,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70073370,"text":"70073370 - 2000 - Late Cenozoic crustal extension and magmatism, southern Death Valley region, California","interactions":[],"lastModifiedDate":"2014-01-16T14:20:19","indexId":"70073370","displayToPublicDate":"2000-01-01T14:02:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1724,"text":"GSA Field Guides","active":true,"publicationSubtype":{"id":10}},"title":"Late Cenozoic crustal extension and magmatism, southern Death Valley region, California","docAbstract":"The late Cenozoic geologic history of the southern Death Valley region is characterized by coeval crustal extension and magamatism. Crustal extension is accommodated by numerous listric and planar normal faults as well as right- and left-lateral strike slip faults. The normal faults sip 30°-50° near the surface and flatten and merge leozoic miogeoclinal rocks; the strike-slip faults act as tear faults between crustal blocks that have extended at different times and at different rates. Crustal extension began 13.4-13.1 Ma and migrated northwestward with time; undeformed basalt flows and lacustrine deposits suggest that extension stopped in this region (but continued north of the Death Valley graben) between 5 and 7 Ma. Estimates of crustal extension in this region vary from 30-50 percent to more than 100 percent. Magmatic rocks syntectonic with crustal extension in the southern Death Valley region include 12.4-6.4 Ma granitic rocks as well as bimodal 14.0-4.0 Ma volcanic rocks. Geochemical and isotopic evidence suggest that the granitic rocks get younger and less alkalic from south to north; the volcanic rocks become more mafic with less evidence of crustal interaction as they get younger. The close spatial and temporal relation between crustal extension and magmatism suggest a genetic and probably a dynamic relation between these geologic processes. We propose a rectonic-magmatic model that requires heat to be transported into the crust by mantle-derived mafic magmas. These magmas pond at lithologic or rheologic boundaries, begin the crystallize, and partially melt the surrounding crustal rocks. With time, the thermally weakened crust is extended (given a regional extensional stress field) concurrent with granitic magmatism and bimodal volcanism.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"GSA Field Guides","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Geological Society of America","doi":"10.1130/0-8137-0002-7.135","usgsCitation":"Calzia, J., and Ramo, O., 2000, Late Cenozoic crustal extension and magmatism, southern Death Valley region, California: GSA Field Guides, v. 2, p. 135-164, https://doi.org/10.1130/0-8137-0002-7.135.","productDescription":"30 p.","startPage":"135","endPage":"164","numberOfPages":"30","costCenters":[{"id":657,"text":"Western Geographic Science Center","active":true,"usgs":true}],"links":[{"id":281198,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":281197,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1130/0-8137-0002-7.135"}],"country":"United States","state":"California","otherGeospatial":"Death Valley","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -117.0,35.0 ], [ -117.0,36.5 ], [ -115.0,36.5 ], [ -115.0,35.0 ], [ -117.0,35.0 ] ] ] } } ] }","volume":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd6422e4b0b290850ff430","contributors":{"authors":[{"text":"Calzia, J.P.","contributorId":58614,"corporation":false,"usgs":true,"family":"Calzia","given":"J.P.","affiliations":[],"preferred":false,"id":488658,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ramo, O.T.","contributorId":15520,"corporation":false,"usgs":true,"family":"Ramo","given":"O.T.","email":"","affiliations":[],"preferred":false,"id":488657,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70095005,"text":"70095005 - 2000 - Volumetric evolution of Surtsey, Iceland, from topographic maps and scanning airborne laser altimetry","interactions":[],"lastModifiedDate":"2017-10-05T18:50:54","indexId":"70095005","displayToPublicDate":"2000-01-01T14:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3500,"text":"Surtsey Research","active":true,"publicationSubtype":{"id":10}},"title":"Volumetric evolution of Surtsey, Iceland, from topographic maps and scanning airborne laser altimetry","docAbstract":"The volumetric evolution of Surtsey has been estimated on the basis of digital elevation models derived from NASA scanning airborne laser altimeter surveys (20 July 1998), as well as digitized 1:5,000-scale topographic maps produced by the National Land Survey of Iceland and by Norrman. Subaerial volumes have been computed from co-registered digital elevation models (DEM's) from 6 July 1968, 11 July 1975, 16 July 1993, and 20 July 1998 (scanning airborne laser altimetry), as well as true surface area (above mean sea level). Our analysis suggests that the subaerial volume of Surtsey has been reduced from nearly 0.100 km3 on 6 July 1968 to 0.075 km3 on 20 July 1998. Linear regression analysis of the temporal evolution of Surtsey's subaerial volume indicates that most of its subaerial surface will be at or below mean sea-level by approximately 2100. This assumes a conservative estimate of continuation of the current pace of marine erosion and mass-wasting on the island, including the indurated core of the conduits of the Surtur I and Surtur II eruptive vents. If the conduits are relatively resistant to marine erosion they will become sea stacks after the rest of the island has become a submarine shoal, and some portions of the island could survive for centuries. The 20 July 1998 scanning laser altimeter surveys further indicate rapid enlargement of erosional canyons in the northeastern portion of the partial tephra ring associated with Surtur I. Continued airborne and eventually spaceborne topographic surveys of Surtsey are planned to refine the inter-annual change of its subaerial volume.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Surtsey Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Surtsey Research Society","publisherLocation":"Reykjavík, Iceland","usgsCitation":"Garvin, J., Williams, R., Frawley, J., and Krabill, W., 2000, Volumetric evolution of Surtsey, Iceland, from topographic maps and scanning airborne laser altimetry: Surtsey Research, v. 11, p. 127-134.","productDescription":"8 p.","startPage":"127","endPage":"134","costCenters":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":282844,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Iceland","city":"Surtsey","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -20.619106,63.296102 ], [ -20.619106,63.312529 ], [ -20.591812,63.312529 ], [ -20.591812,63.296102 ], [ -20.619106,63.296102 ] ] ] } } ] }","volume":"11","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd7b3be4b0b2908510e00e","contributors":{"authors":[{"text":"Garvin, J.B.","contributorId":37652,"corporation":false,"usgs":true,"family":"Garvin","given":"J.B.","email":"","affiliations":[],"preferred":false,"id":491054,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Williams, R.S.","contributorId":19189,"corporation":false,"usgs":true,"family":"Williams","given":"R.S.","affiliations":[],"preferred":false,"id":491052,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Frawley, J.J.","contributorId":69889,"corporation":false,"usgs":true,"family":"Frawley","given":"J.J.","email":"","affiliations":[],"preferred":false,"id":491055,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Krabill, W.B.","contributorId":22952,"corporation":false,"usgs":true,"family":"Krabill","given":"W.B.","email":"","affiliations":[],"preferred":false,"id":491053,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70073837,"text":"70073837 - 2000 - Paleozoic subduction complex and Paleozoic-Mesozoic island-arc volcano-plutonic assemblages in the northern Sierra terrane","interactions":[],"lastModifiedDate":"2014-01-22T14:07:27","indexId":"70073837","displayToPublicDate":"2000-01-01T13:52:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1724,"text":"GSA Field Guides","active":true,"publicationSubtype":{"id":10}},"title":"Paleozoic subduction complex and Paleozoic-Mesozoic island-arc volcano-plutonic assemblages in the northern Sierra terrane","docAbstract":"This field trip provides an overview of the stratigraphic and structural evolution of the northern Sierra terrane, which forms a significant part of the wall rocks on the western side of the later Mesozoic Sierra Nevada batholith in California. The terrane consists of a pre-Late Devonian subduction complex (Shoo Fly Complex) overlain by submarine arc-related deposits that record the evolution of three separate island-arc systems in the Late Sevonian-Early Mississippian, Permian, and Late Triassic-Jurassic. The two Paleozoic are packages and the underlying Shoo Fly Complex have an important bearing on plate-tectonic processes affecting the convergent margin outboard of the Paleozoic Cordilleran miogeocline, although their original paleogeographic relations to North America are controversial. The third arc package represents an overlap assemblage that ties the terrane to North America by the Late Triassic and helps constrain the nature and timing of Mesozoic orogenesis. Several of the field-trip stops examine the record of pre-Late Devonian subduction contained in the Shoo Fly Complex, as well as the paleovolcanology of the overlying Devonian to Jurassic arc rocks. Excellent glaciated exposures provide the opportunity to study a cross section through a tilted Devonian volcano-plutonic association. Additional stops focus on plutonic rocks emplaced during the Middle Jurassic arc magmatism in the terrane, and during the main pulse of Cretaceous magmatism in the Sierra Nevada batholith to the east.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"GSA Field Guides","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Geological Society of America","doi":"10.1130/0-8137-0002-7.255","usgsCitation":"Hanson, R.E., Girty, G.H., Harwood, D.S., and Schweickert, R.A., 2000, Paleozoic subduction complex and Paleozoic-Mesozoic island-arc volcano-plutonic assemblages in the northern Sierra terrane: GSA Field Guides, v. 2, p. 255-277, https://doi.org/10.1130/0-8137-0002-7.255.","productDescription":"23 p.","startPage":"255","endPage":"277","numberOfPages":"23","costCenters":[],"links":[{"id":281389,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":281388,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1130/0-8137-0002-7.255"}],"country":"United States","state":"California","otherGeospatial":"Sierra Terrane","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -121.25,39.25 ], [ -121.25,40.25 ], [ -120.25,40.25 ], [ -120.25,39.25 ], [ -121.25,39.25 ] ] ] } } ] }","volume":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd6a92e4b0b29085103548","contributors":{"authors":[{"text":"Hanson, Richard E.","contributorId":72559,"corporation":false,"usgs":true,"family":"Hanson","given":"Richard","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":489117,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Girty, Gary H.","contributorId":99731,"corporation":false,"usgs":true,"family":"Girty","given":"Gary","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":489118,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Harwood, David S.","contributorId":48153,"corporation":false,"usgs":true,"family":"Harwood","given":"David","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":489115,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Schweickert, Richard A.","contributorId":60107,"corporation":false,"usgs":true,"family":"Schweickert","given":"Richard","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":489116,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70094757,"text":"70094757 - 2000 - TES observations of the martian surface and atmosphere","interactions":[],"lastModifiedDate":"2014-02-24T13:58:57","indexId":"70094757","displayToPublicDate":"2000-01-01T13:50:00","publicationYear":"2000","noYear":false,"publicationType":{"id":4,"text":"Book"},"publicationSubtype":{"id":12,"text":"Conference publication"},"title":"TES observations of the martian surface and atmosphere","docAbstract":"The TES instrument is a Fourier transform Michelson interferometer operating with 10 or 5 cm-1 sampling int he thermal infared spectral region from 1700 to 200 cm-1 (~6 to 50 μm) where virtually all minerals have characteristic fundamental vibrational absorption bands (1, 2, 3, 4, 5, 6, 7, 8). The TES data used in this paper are among the 6x107 spectra collected during the early mapping phase of the MGS mission from southern hemisphere winter to early summer (aerocentric longitude, Ls, 107° to 297°. The methodology for separating the surface and atmospheric components of the radiance from Mars, which allows detailed analysis and interpretation of surface mineralogy (9, 10), is described in previous papers (10, 11).","largerWorkTitle":"Second International Conference on Mars Polar Science and Exploration","conferenceTitle":"Second International Conference on Mars Polar Science and Exploration","conferenceDate":"2000-08-21T00:00:00","conferenceLocation":"Reykjavík, Iceland","language":"English","publisher":"Lunar and Planetary Institute","publisherLocation":"Houston, TX","usgsCitation":"Christensen, P.R., Kieffer, H.H., Pearl, J., Conrath, B., Malin, M.C., Clark, R., Morris, R., Banfield, J., Lane, M.D., Smith, M.D., Hamilton, V., and Kuzmin, R., 2000, TES observations of the martian surface and atmosphere, p. 22-23.","productDescription":"p. 22-23","numberOfPages":"2","costCenters":[],"links":[{"id":282698,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd763ae4b0b2908510ac45","contributors":{"authors":[{"text":"Christensen, P. R.","contributorId":7819,"corporation":false,"usgs":false,"family":"Christensen","given":"P.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":490858,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kieffer, H. H.","contributorId":40725,"corporation":false,"usgs":false,"family":"Kieffer","given":"H.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":490863,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Pearl, J.C.","contributorId":45074,"corporation":false,"usgs":true,"family":"Pearl","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":490864,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Conrath, B.","contributorId":39285,"corporation":false,"usgs":true,"family":"Conrath","given":"B.","email":"","affiliations":[],"preferred":false,"id":490862,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Malin, M. C.","contributorId":68830,"corporation":false,"usgs":false,"family":"Malin","given":"M.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":490866,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Clark, R.C.","contributorId":49952,"corporation":false,"usgs":true,"family":"Clark","given":"R.C.","email":"","affiliations":[],"preferred":false,"id":490865,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Morris, R.V.","contributorId":6978,"corporation":false,"usgs":true,"family":"Morris","given":"R.V.","affiliations":[],"preferred":false,"id":490857,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Banfield, J.L.","contributorId":32079,"corporation":false,"usgs":true,"family":"Banfield","given":"J.L.","email":"","affiliations":[],"preferred":false,"id":490861,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Lane, M. D.","contributorId":94826,"corporation":false,"usgs":false,"family":"Lane","given":"M.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":490868,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Smith, M. D.","contributorId":25724,"corporation":false,"usgs":false,"family":"Smith","given":"M.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":490860,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Hamilton, V.E.","contributorId":92024,"corporation":false,"usgs":true,"family":"Hamilton","given":"V.E.","email":"","affiliations":[],"preferred":false,"id":490867,"contributorType":{"id":1,"text":"Authors"},"rank":11},{"text":"Kuzmin, R.O.","contributorId":14932,"corporation":false,"usgs":true,"family":"Kuzmin","given":"R.O.","email":"","affiliations":[],"preferred":false,"id":490859,"contributorType":{"id":1,"text":"Authors"},"rank":12}]}} ,{"id":70074106,"text":"70074106 - 2000 - The value of long-term streamflow records","interactions":[],"lastModifiedDate":"2014-01-27T13:49:02","indexId":"70074106","displayToPublicDate":"2000-01-01T13:47:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3720,"text":"Water Resources Impact","printIssn":"1522-3175","active":true,"publicationSubtype":{"id":10}},"title":"The value of long-term streamflow records","docAbstract":"No abstract available.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Water Resources Impact","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"American Water Resources Association","usgsCitation":"Norris, J.M., 2000, The value of long-term streamflow records: Water Resources Impact, v. 2, no. 4, p. 11-14.","productDescription":"4 p.","startPage":"11","endPage":"14","numberOfPages":"4","costCenters":[],"links":[{"id":281584,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"2","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd78c3e4b0b2908510c5f5","contributors":{"authors":[{"text":"Norris, J. M.","contributorId":87953,"corporation":false,"usgs":true,"family":"Norris","given":"J.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":489407,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70073524,"text":"70073524 - 2000 - An elevational gradient in snowpack chemical loading at Glacier National Park, Montana: implications for ecosystem processes","interactions":[],"lastModifiedDate":"2016-10-13T09:37:33","indexId":"70073524","displayToPublicDate":"2000-01-01T13:42:00","publicationYear":"2000","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"An elevational gradient in snowpack chemical loading at Glacier National Park, Montana: implications for ecosystem processes","docAbstract":"The accumulation and melting of mountain snowpacks are major drivers of ecosystem processes in the Rocky Mountains. These include the influence of snow water equivalent (SWE) timing and amount of release on soil moisture for annual tree growth, and alpine stream discharge and temperature that control aquatic biota life histories. Snowfall also brings with it atmospheric deposition. Snowpacks will hold as much as 8 months of atmospheric deposition for release into mountain ecosystems during the spring melt. These pulses of chemicals influence soil microbiota and biogeochemical processes affecting mountain vegetation growth. Increased atmospheric nitrogen inputs recently have been documented in remote parts of Colorado's mountain systems but no baseline data exist for the Northern Rockies. We examined patterns of SWE and snow chemistry in an elevational gradient stretching from west to east over the continental divide in Glacier National Park in March 1999 and 2000. Sites ranged from 1080m to 2192m at Swiftcurrent Pass. At each site, two vertically-integrated columns of snow were sampled from snowpits up to 600cm deep and analyzed for major cations and anions. Minor differences in snow chemistry, on a volumetric basis, existed over the elvational gradient. Snowpack chemical loading estimates were calculated for NH4, SO4 and NO3 and closely followed elevational increases in SWE. NO3 (in microequivalents/square meter) ranged from 1,000 ueq/m2 at low elevation sites to 8,000+ ueq/m2 for high elevation sites. Western slopes received greater amounts of SWE and chemical loads for all tested compounds.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Proceedings of the 2000 International Snow Science Workshop","largerWorkSubtype":{"id":12,"text":"Conference publication"},"conferenceTitle":"A merging of theory & practice: ISSW 2000","conferenceLocation":"Big Sky, MT","language":"English","publisher":"International Snow Science Workshop","publisherLocation":"Bozeman, MT","usgsCitation":"Fagre, D., Tonnessen, K., Morris, K., Ingersoll, G., McKeon, L., and Holzer, K., 2000, An elevational gradient in snowpack chemical loading at Glacier National Park, Montana: implications for ecosystem processes, in Proceedings of the 2000 International Snow Science Workshop, Big Sky, MT, p. 462-467.","productDescription":"6 p.","startPage":"462","endPage":"467","numberOfPages":"6","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":481,"text":"Northern Rocky Mountain Science Center","active":true,"usgs":true}],"links":[{"id":281249,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Montana","otherGeospatial":"Glacier National Park","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -114.4755,48.2337 ], [ -114.4755,49.001 ], [ -113.242,49.001 ], [ -113.242,48.2337 ], [ -114.4755,48.2337 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd4c74e4b0b290850f0ff1","contributors":{"authors":[{"text":"Fagre, Daniel","contributorId":68649,"corporation":false,"usgs":true,"family":"Fagre","given":"Daniel","affiliations":[],"preferred":false,"id":488889,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Tonnessen, Kathy","contributorId":62135,"corporation":false,"usgs":true,"family":"Tonnessen","given":"Kathy","affiliations":[],"preferred":false,"id":488888,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Morris, Kristi","contributorId":45197,"corporation":false,"usgs":true,"family":"Morris","given":"Kristi","affiliations":[],"preferred":false,"id":488887,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Ingersoll, George","contributorId":25863,"corporation":false,"usgs":true,"family":"Ingersoll","given":"George","affiliations":[],"preferred":false,"id":488885,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"McKeon, Lisa","contributorId":43668,"corporation":false,"usgs":true,"family":"McKeon","given":"Lisa","affiliations":[],"preferred":false,"id":488886,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Holzer, Karen","contributorId":89055,"corporation":false,"usgs":true,"family":"Holzer","given":"Karen","email":"","affiliations":[],"preferred":false,"id":488890,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70073836,"text":"ofr2000411 - 2000 - Data for Quaternary faults in western Montana","interactions":[],"lastModifiedDate":"2014-01-22T13:47:54","indexId":"ofr2000411","displayToPublicDate":"2000-01-01T13:40:00","publicationYear":"2000","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":330,"text":"Open-File Report","code":"OFR","onlineIssn":"2331-1258","printIssn":"0196-1497","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2000-411","title":"Data for Quaternary faults in western Montana","docAbstract":"The \"World Map of Major Active Faults\" Task Group is compiling published fault data, developing a digital\ndatabase of the fault data, and preparing a series of maps for the United States and other countries in the western\nHemisphere. The data is intended to portray the locations, ages, and activity rates of major earthquake-related\nfeatures such as faults, folds, and liquefaction features that have geologic evidence of Quaternary (1.6 Ma)\ndeformation. The Western Hemisphere effort is sponsored by International Lithosphere Program (ILP) Task Group\nII-2; the data compilation, database, and map for the United States is funded largely by the National Earthquake\nHazard Reduction Program (NEHRP) through the U.S. Geological Survey. The ILP effort in the Western\nHemisphere is coordinated by Michael N. Machette, the digital database is designed and managed Kathleen M.\nHaller, and map data are digitized and manipulated by Richard L. Dart. In addition to meeting the goals of the Task\nGroup II-2, this effort represents a key contribution to the new Global Seismic Hazards Assessment Program (ILP\nTask Group II-0) for the International Decade for Natural Disaster Reduction.\nThis compilation, which documents the published data on Quaternary surface faulting in western Montana, is one of\nmany similar state or regional compilations that are planned for the project. Compilations for Arizona (Pearthree,\n1998 #2945), Colorado (Widmann and others, 1998 #3441), New Mexico (Machette and others, 1998), and West\nTexas (Collins and others, 1996 #993) are currently available and the compilation for features east of the Rocky\nMountain front will be available in early 2000 (Crone and Wheeler, in press). All are primarily a catalog of data that\nincludes a variety of geographic, geologic, and paleoseismologic parameters for known or assumed Quaternary\nfaults. These data compilations, the digital database, and the companion maps summarize the published information\non known tectonic features and present the information in an internally consistent format. The compilations will be\navailable in digital database format on the WorldWide Web in the near future, which will greatly improve their\nutility. Release of data for individual states and regions within the United States in this text-based format was\nnecessary because of the time required to develop the national database.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ofr2000411","collaboration":"Prepared as part of the U.S. Geological Survey’s National Earthquake Hazard Reduction Program (NEHRP) project on UNITED STATES MAP OF QUATERNARY FAULTS AND FOLDS. In cooperation with the International Lithosphere Program’s Task Group II-2, World Map of Major Active Faults Michael N. Machette, Co-chairman.","usgsCitation":"Haller, K., Dart, R.L., Machette, M., and Stickney, M., 2000, Data for Quaternary faults in western Montana: U.S. Geological Survey Open-File Report 2000-411, v, 229 p., https://doi.org/10.3133/ofr2000411.","productDescription":"v, 229 p.","numberOfPages":"241","costCenters":[{"id":414,"text":"National Earthquake Hazards Reduction Program","active":false,"usgs":true}],"links":[{"id":281387,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"}],"country":"United States","state":"Montana","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -116.05,44.3582 ], [ -116.05,49.0014 ], [ -108.9944,49.0014 ], [ -108.9944,44.3582 ], [ -116.05,44.3582 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd53b5e4b0b290850f550b","contributors":{"authors":[{"text":"Haller, Kathleen M. haller@usgs.gov","contributorId":1331,"corporation":false,"usgs":true,"family":"Haller","given":"Kathleen M.","email":"haller@usgs.gov","affiliations":[{"id":300,"text":"Geologic Hazards Science Center","active":true,"usgs":true}],"preferred":false,"id":489112,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dart, Richard L. dart@usgs.gov","contributorId":1209,"corporation":false,"usgs":true,"family":"Dart","given":"Richard","email":"dart@usgs.gov","middleInitial":"L.","affiliations":[],"preferred":true,"id":489111,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Machette, Michael N.","contributorId":28963,"corporation":false,"usgs":true,"family":"Machette","given":"Michael N.","affiliations":[],"preferred":false,"id":489114,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Stickney, Michael C.","contributorId":27786,"corporation":false,"usgs":true,"family":"Stickney","given":"Michael C.","affiliations":[],"preferred":false,"id":489113,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70074099,"text":"70074099 - 2000 - Advances in the hydrogeochemistry and microbiology of acid mine waters","interactions":[],"lastModifiedDate":"2018-12-07T05:54:52","indexId":"70074099","displayToPublicDate":"2000-01-01T13:39:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2020,"text":"International Geology Review","active":true,"publicationSubtype":{"id":10}},"title":"Advances in the hydrogeochemistry and microbiology of acid mine waters","docAbstract":"The last decade has witnessed a plethora of research related to the hydrogeochemistry and microbiology of acid mine waters and associated tailings and waste-rock waters. Numerous books, reviews, technical papers, and proceedings have been published that examine the complex bio-geochemical process of sulfide mineral oxidation, develop and apply geochemical models to site characterization, and characterize the microbial ecology of these environments. This review summarizes many of these recent works, and provides references for those investigating this field. Comparisons of measured versus calculated Eh and measured versus calculated pH for water samples from several field sites demonstrate the reliability of some current geochemical models for aqueous speciation and mass balances. Geochemical models are not, however, used to predict accurately time-dependent processes but to improve our understanding of these systems and to constrain possible processes that contribute to actual or potential water quality issues. Microbiological studies are demonstrating that there is much we have yet to learn about the types of different microorganisms and their function and ecology in mine-waste environments. A broad diversity of green algae, bacteria, archaea, yeasts, and fungi are encountered in acid mine waters, and a better understanding of their ecology and function may potentially enhance remediation possibilities as well as our understanding of the evolution of life.","language":"English","publisher":"Taylor & Francis","doi":"10.1080/00206810009465095","usgsCitation":"Nordstrom, D.K., 2000, Advances in the hydrogeochemistry and microbiology of acid mine waters: International Geology Review, v. 42, no. 6, p. 499-515, https://doi.org/10.1080/00206810009465095.","productDescription":"17 p.","startPage":"499","endPage":"515","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":281582,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1080/00206810009465095"},{"id":281583,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"42","issue":"6","noUsgsAuthors":false,"publicationDate":"2010-07-06","publicationStatus":"PW","scienceBaseUri":"53cd4b3ae4b0b290850f03e9","contributors":{"authors":[{"text":"Nordstrom, D. Kirk 0000-0003-3283-5136 dkn@usgs.gov","orcid":"https://orcid.org/0000-0003-3283-5136","contributorId":749,"corporation":false,"usgs":true,"family":"Nordstrom","given":"D.","email":"dkn@usgs.gov","middleInitial":"Kirk","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true}],"preferred":false,"id":489400,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70074663,"text":"70074663 - 2000 - A preliminary re-evaluation of the stratigraphy of the Roubidoux Formation of Missouri and correlative Lower Ordovician units in the southern midcontinent","interactions":[],"lastModifiedDate":"2014-01-31T13:45:42","indexId":"70074663","displayToPublicDate":"2000-01-01T13:34:00","publicationYear":"2000","noYear":false,"publicationType":{"id":4,"text":"Book"},"publicationSubtype":{"id":12,"text":"Conference publication"},"title":"A preliminary re-evaluation of the stratigraphy of the Roubidoux Formation of Missouri and correlative Lower Ordovician units in the southern midcontinent","docAbstract":"No abstract available.","largerWorkTitle":"Platform carbonates in the southern midcontinent, 1996 symposium: proceedings of a symposium held March 26-27, 1996, in Oklahoma City","conferenceTitle":"Platform carbonates in the southern midcontinent, 1996 symposium","conferenceDate":"1996-01-25T00:00:00","conferenceLocation":"Oklahoma City, OK","language":"English","publisher":"Oklahoma Geological Survey","publisherLocation":"Norman, OK","usgsCitation":"Repetski, J., Loch, J.D., Ethington, R.L., and Dresbach, R., 2000, A preliminary re-evaluation of the stratigraphy of the Roubidoux Formation of Missouri and correlative Lower Ordovician units in the southern midcontinent, p. 103-106.","productDescription":"p. 103-106","numberOfPages":"4","costCenters":[],"links":[{"id":281841,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Missouri","otherGeospatial":"Roubidoux Formation","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -93.51,36.0 ], [ -93.51,38.22 ], [ -89.1,38.22 ], [ -89.1,36.0 ], [ -93.51,36.0 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd4a50e4b0b290850efb2e","contributors":{"authors":[{"text":"Repetski, J.E.","contributorId":38579,"corporation":false,"usgs":true,"family":"Repetski","given":"J.E.","affiliations":[],"preferred":false,"id":489729,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Loch, James D.","contributorId":20139,"corporation":false,"usgs":false,"family":"Loch","given":"James","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":489728,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ethington, Raymond L.","contributorId":93507,"corporation":false,"usgs":false,"family":"Ethington","given":"Raymond","email":"","middleInitial":"L.","affiliations":[{"id":6754,"text":"University of Missouri","active":true,"usgs":false}],"preferred":false,"id":489731,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Dresbach, R.I.","contributorId":41338,"corporation":false,"usgs":true,"family":"Dresbach","given":"R.I.","email":"","affiliations":[],"preferred":false,"id":489730,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70073940,"text":"70073940 - 2000 - Central San Juan caldera cluster: Regional volcanic framework","interactions":[],"lastModifiedDate":"2017-04-14T10:37:48","indexId":"70073940","displayToPublicDate":"2000-01-01T13:33:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1727,"text":"GSA Special Papers","active":true,"publicationSubtype":{"id":10}},"title":"Central San Juan caldera cluster: Regional volcanic framework","docAbstract":"Eruption of at least 8800 km3 of dacitic-rhyolitic magma as 9 major ash-slow sheets (individually 150-5000 km3) was accompanied by recurrent caldera subsidence between 28.3 and about 26.5 Ma in the central San Juan Mountains, Colorado. Voluminous andesitic-decitic lavas and breccias were erupted from central volcanoes prior to the ash-flow eruptions, and similar lava eruptions continued within and adjacent to the calderas during the period of explosive volcanism, making the central San Juan caldera cluster an exceptional site for study of caldera-related volcanic processes. Exposed calderas vary in size from 10 to 75 km in maximum diameter, the largest calderas being associated with the most voluminous eruptions. After collapse of the giant La Garita caldera during eruption if the Fish Canyon Tuff at 17.6 Ma, seven additional explosive eruptions and calderas formed inside the La Garita depression within about 1 m.y. Because of the nested geometry, maximum loci of recurrently overlapping collapse events are inferred to have subsided as much as 10-17 km, far deeper than the roof of the composite subvolcanic batholith defined by gravity data, which represents solidified caldera-related magma bodies. Erosional dissection to depths of as much as 1.5 km, although insufficient to reach the subvolcanic batholith, has exposed diverse features of intracaldera ash-flow tuff and interleaved caldera-collapse landslide deposits that accumulated to multikilometer thickness within concurrently subsiding caldera structures. The calderas display a variety of postcollapse resurgent uplift structures, and caldera-forming events produced complex fault geometries that localized late mineralization, including the epithermal base- and precious-metal veins of the well-known Creede mining district. Most of the central San Juan calderas have been deeply eroded, and their identification is dependent on detailed geologic mapping. In contrast, the primary volcanic morphology of the symmetrically resurgent Creede caldera, the volcanic framework for Lake Creede, has been exceptionally preserved because of rapid infilling by moat sediments of the Creede Formation, which were preferentially eroded during the past few million years. The ash-flow tuffs and caldera of the central San Juan region have been widely recognized as exceptional sites for study of explosive volcanic processes, and the results reported here provide new insights into processes of pyroclastic eruption and emplacement, geometric interrelations between caldera subsidence and resurgence, the petrologic diversity of sequential ash-flow eruptions, recurrent eruption of intermediate-composition lavas after each caldera-forming event, associated regional fault development, volume relations between ash-flow eruptions and associated calderas, the emplacement of subvolcanic batholiths, and involvement of mantle-derived mafic phases in magma-generation processes.","language":"English","publisher":"Geological Society of America","doi":"10.1130/0-8137-2346-9.9","usgsCitation":"Lipman, P.W., 2000, Central San Juan caldera cluster: Regional volcanic framework: GSA Special Papers, v. 346, p. 9-69, https://doi.org/10.1130/0-8137-2346-9.9.","productDescription":"61 p.","startPage":"9","endPage":"69","costCenters":[],"links":[{"id":281508,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","otherGeospatial":"San Juan Caldera Cluster","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -108.0,35.0 ], [ -108.0,40.0 ], [ -104.0,40.0 ], [ -104.0,35.0 ], [ -108.0,35.0 ] ] ] } } ] }","volume":"346","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd5061e4b0b290850f34de","contributors":{"authors":[{"text":"Lipman, Peter W. 0000-0001-9175-6118 plipman@usgs.gov","orcid":"https://orcid.org/0000-0001-9175-6118","contributorId":3486,"corporation":false,"usgs":true,"family":"Lipman","given":"Peter","email":"plipman@usgs.gov","middleInitial":"W.","affiliations":[{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true},{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"preferred":true,"id":489255,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70073835,"text":"70073835 - 2000 - Flow of nitrogen into Mississippi Basin believed to cause Gulf hypoxia","interactions":[],"lastModifiedDate":"2014-01-22T13:32:47","indexId":"70073835","displayToPublicDate":"2000-01-01T13:27:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1428,"text":"Earth in Space","active":true,"publicationSubtype":{"id":10}},"title":"Flow of nitrogen into Mississippi Basin believed to cause Gulf hypoxia","docAbstract":"No abstract available.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Earth in Space","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"American Geophysical Union","usgsCitation":"Goolsby, D.A., 2000, Flow of nitrogen into Mississippi Basin believed to cause Gulf hypoxia: Earth in Space, v. 13, no. 3, p. 6-10.","productDescription":"5 p.","startPage":"6","endPage":"10","numberOfPages":"5","costCenters":[],"links":[{"id":281384,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"Mississippi Basin","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -113.11,28.94 ], [ -113.11,49.0 ], [ -75.96,49.0 ], [ -75.96,28.94 ], [ -113.11,28.94 ] ] ] } } ] }","volume":"13","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd59f4e4b0b290850f908e","contributors":{"authors":[{"text":"Goolsby, Donald A.","contributorId":46083,"corporation":false,"usgs":true,"family":"Goolsby","given":"Donald","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":489110,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70094999,"text":"70094999 - 2000 - Near surface infiltration monitoring neutron moisture logging, Yucca Mountain, Nevada","interactions":[],"lastModifiedDate":"2014-02-26T13:30:47","indexId":"70094999","displayToPublicDate":"2000-01-01T13:26:00","publicationYear":"2000","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Near surface infiltration monitoring neutron moisture logging, Yucca Mountain, Nevada","docAbstract":"No abstract available.","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Vadose zone science and technology solutions","largerWorkSubtype":{"id":4,"text":"Other Government Series"},"language":"English","publisher":"Battelle Press","publisherLocation":"Columbus, OH","isbn":"1574770853","usgsCitation":"Flint, A.L., and Flint, L.E., 2000, Near surface infiltration monitoring neutron moisture logging, Yucca Mountain, Nevada, chap. of Vadose zone science and technology solutions, v. 1, p. 457-474.","productDescription":"18 p.","startPage":"457","endPage":"474","numberOfPages":"18","costCenters":[],"links":[{"id":282835,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Nevada","otherGeospatial":"Yucca Mountain","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -116.494886,36.802912 ], [ -116.494886,36.861755 ], [ -116.436421,36.861755 ], [ -116.436421,36.802912 ], [ -116.494886,36.802912 ] ] ] } } ] }","volume":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd68c1e4b0b29085102430","contributors":{"authors":[{"text":"Flint, A. L.","contributorId":102453,"corporation":false,"usgs":true,"family":"Flint","given":"A.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":491042,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Flint, L. E. 0000-0002-7868-441X","orcid":"https://orcid.org/0000-0002-7868-441X","contributorId":38180,"corporation":false,"usgs":true,"family":"Flint","given":"L.","middleInitial":"E.","affiliations":[],"preferred":false,"id":491041,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70100293,"text":"70100293 - 2000 - Geological monitoring of Surtsey, Iceland, 1967-1998","interactions":[],"lastModifiedDate":"2014-03-31T14:09:21","indexId":"70100293","displayToPublicDate":"2000-01-01T13:25:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3500,"text":"Surtsey Research","active":true,"publicationSubtype":{"id":10}},"title":"Geological monitoring of Surtsey, Iceland, 1967-1998","docAbstract":"Aspects of the geological monitoring of the volcanic island of Surtsey 1967-1998, are described. A hydrothermal system was developed within the tephra craters in late 1966 to early 1967. Temperatures in a drill hole, situated at the eastern border of the hydrothermal area, indicate that the hydrothermal system at that site has been cooling at an average rate of ≤ 1°C per year since 1980. The tephra was altered rapidly within the hydrothermal area, producing the first visible palagonite tuff in 1969. A substantial part of the tephra pile above sea level was probably converted to tuff by 1972. The visible area of tuff has gradually increased since then, primarily due to erosion of tephra at the surface. By 1998 52% of the exposed tephra area had been converted to palagonite tuff. By volume, however, some 80-85% of the tephra pile above sea level has been converted to tuff in 1998. The area of Surtsey has shrunk from its original 2.65 km2 (1967) to 1.47 km2 (1998) due to marine abrasion. The geological formations on Surtsey have, however, responded quite variably to erosion. The tephra pile was easily eroded, but marine abrasion. The central core of palagonite tuff is estimated to be ≤0.39 km2. Statistical estimation of models of the decreases of Surtsey indicate that it will last for a long time. The numerical experiments indicate that it will take over 100 years until only the palagonite tuff core is left. It is postulated that the final remnany of Surtsey before complete destruction will be a palagonite tuff crag, comparable to those of the other islands in the Vestmannaeyjar archipelago.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Surtsey Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Surtsey Research Society","usgsCitation":"Jakobsson, S.P., Gudmundsson, G., and Moore, J.G., 2000, Geological monitoring of Surtsey, Iceland, 1967-1998: Surtsey Research, v. 11, p. 99-108.","productDescription":"10 p.","startPage":"99","endPage":"108","numberOfPages":"10","temporalStart":"1967-01-01","temporalEnd":"1998-12-31","costCenters":[],"links":[{"id":285154,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Iceland","state":"Surtsey","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -20.619106,63.296102 ], [ -20.619106,63.312529 ], [ -20.591812,63.312529 ], [ -20.591812,63.296102 ], [ -20.619106,63.296102 ] ] ] } } ] }","volume":"11","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5355946ee4b0120853e8bfcf","contributors":{"authors":[{"text":"Jakobsson, Sveinn P.","contributorId":40121,"corporation":false,"usgs":true,"family":"Jakobsson","given":"Sveinn","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":492171,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gudmundsson, Gudmundur","contributorId":27359,"corporation":false,"usgs":true,"family":"Gudmundsson","given":"Gudmundur","email":"","affiliations":[],"preferred":false,"id":492170,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Moore, James G. 0000-0002-7543-2401 jmoore@usgs.gov","orcid":"https://orcid.org/0000-0002-7543-2401","contributorId":2892,"corporation":false,"usgs":true,"family":"Moore","given":"James","email":"jmoore@usgs.gov","middleInitial":"G.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true},{"id":114,"text":"Alaska Science Center","active":true,"usgs":true}],"preferred":true,"id":492169,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70073651,"text":"70073651 - 2000 - Applications of imaging spectroscopy data: A case study at Summitville, Colorado","interactions":[],"lastModifiedDate":"2018-05-03T16:15:42","indexId":"70073651","displayToPublicDate":"2000-01-01T13:24:00","publicationYear":"2000","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Applications of imaging spectroscopy data: A case study at Summitville, Colorado","docAbstract":"From 1985 through 1992, the Summitville open-pit mine produced gold from lowgrade ore using cyanide heap-leach techniques, a method to extract gold whereby the ore pile is sprayed with water containing cyanide, which dissolves the minute gold grains. Environmental problems due to mining activity at Summitville include significant increases in acidic and metal-rich drainage from the site, leakage of cyanide-bearing solutions from the heap-leach pad into an underdrain system, and several surface leaks of cyanide-bearing solutions into the Wightman Fork of the Alamosa River. In general, drainage from the Summitville mine moves downslope into the Wightman Fork, a small tributary of the Alamosa River, which in turn flows east into the Terrace Reservoir before entering the agricultural lands of the San Luis Valley. The increase in the trace-metal burden of the Alamosa River watershed due to the mining activities at Summitville is of concern to farmers and fisherman, as well as Federal and State of Colorado agencies having responsibility for land stewardship.
The environment of the Summitville area is a result of 1) its geologic evolution, that culminated in the formation of precious-metal mineral deposits; and 2) previous metal mining activity. Mining accentuates, accelerates, and pertubates natural geochemical processes. The development of underground workings, open pits, mill tailings, and spoil heaps and the extractive processing of ore enhances the likelihood of releasing chemicals and elements to the surrounding areas and at increased rates relative to unmined areas. Both mined and unmined mineralized areas can produce acid drainage from the formation and movement of highly acidic water rich in heavy metals. This acidic water forms principally through the chemical reaction of oxygenated surface water and shallow subsurface water with rocks that contain sulfide minerals, producing sulphuric acid. Heavy metals can be leached by the acid solution that comes in contact with mineralized rocks, a process that may be enhanced by bacterial action. The resulting fluids may be highly toxic and, when mixed with groundwater, surface water, and soil, may have harmful effects on humans, animals, and plants. Thus, understanding the geologic and hydrologic history of this area is a critical piece of the environmental puzzle in the Summitville area.
The Summitville mine operators had ceased active mining and begun environmental remediation, including treatment of the heap-leach pile and installation of a water-treatment facility, when it declared bankruptcy in December 1992 and abandoned the mine site. The U.S. Environmental Protection Agency (EPA) immediately took over the Summitville site under EPA Superfund Emergency Response authority.
Summitville has focused public attention on the environmental effects of modern mineral-resource development. Soon after the mine was abandoned, Federal, State, and local agencies, along with Alamosa River water users and private companies, began extensive studies at the mine site and surrounding areas. These studies included analysis of water, soil, livestock and vegetation. The role of the U.S. Geological Survey (USGS) was to provide geologic, hydrologic and agricultural information about the mine and surrounding area and to describe and evaluate the environmental condition of the Summitville mine and the downstream effects of the mine on the San Luis Valley (King 1995).
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Remote sensing for site characterization","language":"English","publisher":"Springer","doi":"10.1007/978-3-642-56978-4_6","usgsCitation":"King, T., Clark, R.N., and Swayze, G.A., 2000, Applications of imaging spectroscopy data: A case study at Summitville, Colorado, chap. of Remote sensing for site characterization, p. 164-185, https://doi.org/10.1007/978-3-642-56978-4_6.","productDescription":"22 p.","startPage":"164","endPage":"185","numberOfPages":"22","costCenters":[{"id":35995,"text":"Geology, Geophysics, and Geochemistry Science Center","active":true,"usgs":true}],"links":[{"id":281289,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","city":"Summitville","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd4da5e4b0b290850f19f7","contributors":{"authors":[{"text":"King, Trude","contributorId":29831,"corporation":false,"usgs":true,"family":"King","given":"Trude","email":"","affiliations":[],"preferred":false,"id":488979,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Clark, Roger N. 0000-0002-7021-1220 rclark@usgs.gov","orcid":"https://orcid.org/0000-0002-7021-1220","contributorId":515,"corporation":false,"usgs":true,"family":"Clark","given":"Roger","email":"rclark@usgs.gov","middleInitial":"N.","affiliations":[{"id":211,"text":"Crustal Geophysics and Geochemistry Science Center","active":true,"usgs":true}],"preferred":true,"id":488977,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Swayze, Gregg A. 0000-0002-1814-7823 gswayze@usgs.gov","orcid":"https://orcid.org/0000-0002-1814-7823","contributorId":518,"corporation":false,"usgs":true,"family":"Swayze","given":"Gregg","email":"gswayze@usgs.gov","middleInitial":"A.","affiliations":[{"id":211,"text":"Crustal Geophysics and Geochemistry Science Center","active":true,"usgs":true},{"id":309,"text":"Geology and Geophysics Science Center","active":true,"usgs":true}],"preferred":true,"id":488978,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70094998,"text":"70094998 - 2000 - The Edwards Aquifer Authority and U.S. Geological Survey Water Resources Program Quarterly Report- 04/01/2000 to 07/31/2000","interactions":[],"lastModifiedDate":"2014-03-25T10:32:21","indexId":"70094998","displayToPublicDate":"2000-01-01T13:22:00","publicationYear":"2000","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":6,"text":"USGS Unnumbered Series"},"title":"The Edwards Aquifer Authority and U.S. Geological Survey Water Resources Program Quarterly Report- 04/01/2000 to 07/31/2000","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/70094998","usgsCitation":"U.S. Geological Survey, 2000, The Edwards Aquifer Authority and U.S. Geological Survey Water Resources Program Quarterly Report- 04/01/2000 to 07/31/2000, https://doi.org/10.3133/70094998.","numberOfPages":"16","costCenters":[],"links":[{"id":284829,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/unnumbered/70094998/report.pdf"},{"id":282836,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/70094998.JPG"}],"country":"United States","state":"Texas","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -103.78,29.61 ], [ -103.78,34.45 ], [ -93.85,34.45 ], [ -93.85,29.61 ], [ -103.78,29.61 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5355959ce4b0120853e8c260"} ,{"id":70074380,"text":"70074380 - 2000 - Evaluating temporal changes in stream condition in three New Jersey rive basins by using an index of biotic integrity","interactions":[],"lastModifiedDate":"2014-01-29T13:30:35","indexId":"70074380","displayToPublicDate":"2000-01-01T13:17:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1131,"text":"Bulletin of the New Jersey Academy of Science","active":true,"publicationSubtype":{"id":10}},"title":"Evaluating temporal changes in stream condition in three New Jersey rive basins by using an index of biotic integrity","docAbstract":"An index of biotic integrity (!B!) modified for New Jersey streams was used to compare changes in stream condition from the 1970s to the 1990s in Delaware, Passaic, and Raritan River Basins. Stream condition was assessed at 88 sampling locations. Mean IBI scores for all basins increased from the 1970s to the 1990s, but the stream-condition category improved (from fair to good) only for the Delaware River Basin. The number of benthic insectivores and the proportion of insectivorous cyprinds increased in all three basins; however, the number of white suckers decreased significantly only in the Delaware River Basin. Results of linear-regression analysis indicate a significant correlation between the percentage of altered land in the basin and change in IBI score (1970s to 1990s) for Delaware River sites. Results of analysis of variance of the rank-transformed IBI scores for the 1970s and 1990s indicate that the three basins was equal in the 1970s. Results of a multiple-comparison test demonstrated that the 1990s IBI values for the Delaware River Basin differed significantly from those for the Passaic and Raritan River Basins. Many factors, such as the imposition of the more stringent standards on water-water and industrial discharges during the 1980s and changes in land-use practices, likely contributed to the change in the Delaware River Basin. A general increase in IBI values for the Passaic, Raritan, and Delaware River Basins over the past 25 years appears to reflect overall improvements in water quality.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Bulletin of the New Jersey Academy of Science","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"New Jersey Academy of Science","usgsCitation":"Chang, M., Kennen, J., and Del Corso, E., 2000, Evaluating temporal changes in stream condition in three New Jersey rive basins by using an index of biotic integrity: Bulletin of the New Jersey Academy of Science, v. 45, no. 1, p. 1-12.","productDescription":"12 p.","startPage":"1","endPage":"12","numberOfPages":"12","costCenters":[],"links":[{"id":281661,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"New Jersey","otherGeospatial":"Delaware River Basin;Passaic River Basin;Raritan River Basin","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -75.5598,38.9286 ], [ -75.5598,41.3574 ], [ -73.9024,41.3574 ], [ -73.9024,38.9286 ], [ -75.5598,38.9286 ] ] ] } } ] }","volume":"45","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd583ee4b0b290850f7f81","contributors":{"authors":[{"text":"Chang, Ming","contributorId":80318,"corporation":false,"usgs":true,"family":"Chang","given":"Ming","email":"","affiliations":[],"preferred":false,"id":489548,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kennen, Jonathan G. 0000-0002-5426-4445 jgkennen@usgs.gov","orcid":"https://orcid.org/0000-0002-5426-4445","contributorId":574,"corporation":false,"usgs":true,"family":"Kennen","given":"Jonathan G.","email":"jgkennen@usgs.gov","affiliations":[{"id":470,"text":"New Jersey Water Science Center","active":true,"usgs":true}],"preferred":true,"id":489547,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Del Corso, Ellyn","contributorId":107191,"corporation":false,"usgs":true,"family":"Del Corso","given":"Ellyn","email":"","affiliations":[],"preferred":false,"id":489549,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":64506,"text":"64506 - 2000 - IFR enroute low altitude","interactions":[],"lastModifiedDate":"2014-07-15T13:15:15","indexId":"64506","displayToPublicDate":"2000-01-01T13:14:16","publicationYear":"2000","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":6,"text":"USGS Unnumbered Series"},"title":"IFR enroute low altitude","docAbstract":"No abstract available.","language":"English","publisher":"National Ocean Service","publisherLocation":"Silver Spring, MD","doi":"10.3133/64506","usgsCitation":"United States., 2000, IFR enroute low altitude, https://doi.org/10.3133/64506.","costCenters":[],"links":[{"id":290137,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"}],"scale":"1000000","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53c64d95e4b0001bd5147776","contributors":{"authors":[{"text":"United States.","contributorId":128148,"corporation":true,"usgs":false,"organization":"United States.","id":533633,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ]}