No abstract available
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Guidebook for the Red Lodge-Beartooth Mountains-Stillwater area","largerWorkSubtype":{"id":15,"text":"Monograph"},"language":"English","usgsCitation":"Elliot, J.E., Kirk, A.R., and Johnson, T., 1992, Field guide: Gold-copper-silver deposits of the New World District Northwest Geology, chap. of Guidebook for the Red Lodge-Beartooth Mountains-Stillwater area, p. 1-20.","productDescription":"20 p.","startPage":"1","endPage":"20","costCenters":[],"links":[{"id":339197,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58e60285e4b09da6799ac6e7","contributors":{"editors":[{"text":"Elliott, J. E.","contributorId":19914,"corporation":false,"usgs":true,"family":"Elliott","given":"J.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":688646,"contributorType":{"id":2,"text":"Editors"},"rank":1}],"authors":[{"text":"Elliot, J. E.","contributorId":95029,"corporation":false,"usgs":true,"family":"Elliot","given":"J.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":688643,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kirk, A. R.","contributorId":34911,"corporation":false,"usgs":true,"family":"Kirk","given":"A.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":688644,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Johnson, T.W.","contributorId":61169,"corporation":false,"usgs":true,"family":"Johnson","given":"T.W.","email":"","affiliations":[],"preferred":false,"id":688645,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":29248,"text":"wri914009 - 1991 - Major-ion and selected trace-metal chemistry of the Biscayne Aquifer, Southeast Florida","interactions":[],"lastModifiedDate":"2021-10-14T12:08:11.998557","indexId":"wri914009","displayToPublicDate":"2021-10-13T11:05:00","publicationYear":"1991","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"91-4009","displayTitle":"Major-Ion and Selected Trace-Metal Chemistry of the Biscayne Aquifer, Southeast Florida","title":"Major-ion and selected trace-metal chemistry of the Biscayne Aquifer, Southeast Florida","docAbstract":"The major-ion and selected trace-metal chemistry of the Biscayne aquifer was characterized as part of the Florida Ground-Water Quality Monitoring Network Program, a multiagency cooperative effort concerned with delineating baseline water quality for major aquifer systems in the State. The Biscayne aquifer is unconfined and serves as the sole source of drinking water for more than 3 million people in southeast Florida. The Biscayne aquifer consists of highly permeable interbedded limestone and sandstone of Pleistocene and Pliocene age underlying most of Dade and Broward Counties and parts of Palm Beach and Monroe Counties. The high permeability is largely caused by extensive carbonate dissolution.\r\n\r\nWater sampled from 189 wells tapping the Biscayne aquifer was predominantly a calcium bicarbonate type with some mixed types occurring in coastal areas and near major canals. Major - ion is areally uniform throughout the aquifer. According to nonparametric statistical tests of major ions and dissolved solids, the concentrations of calcium, sodium, bicarbonate, and dissolved solids increased significantly with well depth ( 0.05 significance level ), probably a result of less circulation at depth. Potassium and nitrate concentrations decreased significantly with depth. Although the source of recharge to the aquifer varies seasonally, there was no statistical difference in the concentration of major ions in pared water samples from 27 shallow wells collected during wet and dry seasons.\r\n\r\nMedian concentrations for barium, chromium, copper, lead, and manganese were below maximum or secondary maximum contaminant levels set by the US Environmental Protection Agency. The median iron concentration only slightly exceeded the secondary maximum contaminant level. The concentration of barium was significantly related (0.05 significance level) to calcium and bicarbonate concentration. No distinct areal pattern or vertical distribution of the selected trace metals was evident in water from the Biscayne aquifer. Sources for trace metals found in water from the Biscayne aquifer may include local contamination, well-construction techniques, canal - aquifer interactions, and natural occurrence in area soils and rock.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/wri914009","collaboration":"Prepared in cooperation with the Florida Department of Environmental Regulation","usgsCitation":"Radell, M., and Katz, B., 1991, Major-ion and selected trace-metal chemistry of the Biscayne Aquifer, Southeast Florida: U.S. Geological Survey Water-Resources Investigations Report 91-4009, iv, 18 p., https://doi.org/10.3133/wri914009.","productDescription":"iv, 18 p.","costCenters":[{"id":27821,"text":"Caribbean-Florida Water Science Center","active":true,"usgs":true}],"links":[{"id":58101,"rank":299,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1991/4009/wri914009.pdf","text":"Report","size":"1.62 MB","linkFileType":{"id":1,"text":"pdf"},"description":"WRI 91-4009"},{"id":124411,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1991/4009/report-thumb.jpg"}],"country":"United States","state":"Florida","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -80.85937499999999,\n 25.0258840632448\n ],\n [\n -79.8046875,\n 25.0258840632448\n ],\n [\n -79.8046875,\n 27.916766641249065\n ],\n [\n -80.85937499999999,\n 27.916766641249065\n ],\n [\n -80.85937499999999,\n 25.0258840632448\n ]\n ]\n ]\n }\n }\n ]\n}","contact":"Caribbean-Florida Water Science Center
U.S. Geological Survey
3321 College Avenue
Davie, FL 33314
Surf scoters (Melanitta perspicillata) were collected from 6 locations in San Francisco Bay during January and March 1985. Overall, mean concentrations of cadmium and zinc were higher in livers of scoters from the southern region of the Bay, whereas mean iron and lead were higher in those from the northern Bay region. Mean concentrations of arsenic, copper, lead, zinc, aluminum (January only) and iron (January) also differed among individual locations. Mean concentrations of copper and zinc increased, arsenic decreased, and cadmium remained the same between January and March. Selenium and mercury concentrations in scoter livers were not significantly correlated (P>0.05), but cadmium concentrations in livers and kidneys were positively correlated (P<0.0001), and body weight was negatively related to mercury concentration in the liver (P<0.05). Body weight differed among locations but not between January and March. Body weight was correlated with lipid content (P<0.0001). DDE and PCBs were each detected in 34 of 36 scoter carcasses. DDE increased significantly between January and March at Richmond Harbor, but BCBs did not differ between January and March at the 3 locations that could be tested.
","language":"English","publisher":"Springer","doi":"10.1007/BF00394973","usgsCitation":"Ohlendorf, H.M., Marois, K.C., Lowe, R.W., Harvey, T.E., and Kelly, P., 1991, Trace elements and organochlorines in surf scoters from San Francisco Bay, 1985: Environmental Monitoring and Assessment, v. 18, no. 2, p. 105-122, https://doi.org/10.1007/BF00394973.","productDescription":"18 p.","startPage":"105","endPage":"122","numberOfPages":"18","costCenters":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":198072,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"18","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a4ee4b07f02db627e9d","contributors":{"authors":[{"text":"Ohlendorf, H. M.","contributorId":28194,"corporation":false,"usgs":true,"family":"Ohlendorf","given":"H.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":337572,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Marois, Katherine C.","contributorId":10000,"corporation":false,"usgs":true,"family":"Marois","given":"Katherine","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":337571,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lowe, Roy W.","contributorId":50847,"corporation":false,"usgs":false,"family":"Lowe","given":"Roy","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":337574,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Harvey, Thomas E.","contributorId":38089,"corporation":false,"usgs":true,"family":"Harvey","given":"Thomas","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":337573,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Kelly, P.R.","contributorId":82640,"corporation":false,"usgs":true,"family":"Kelly","given":"P.R.","email":"","affiliations":[],"preferred":false,"id":337575,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":5222974,"text":"5222974 - 1991 - Accumulation of trace elements and organochlorines by surf scoters wintering in the Pacific northwest","interactions":[],"lastModifiedDate":"2012-02-02T00:15:10","indexId":"5222974","displayToPublicDate":"2010-06-16T12:18:02","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2901,"text":"Northwestern Naturalist","active":true,"publicationSubtype":{"id":10}},"title":"Accumulation of trace elements and organochlorines by surf scoters wintering in the Pacific northwest","docAbstract":"Selenium, cadmium, mercury, copper, manganese, zinc, aluminum, lead, PCBs and DDE were accumulated by segments of the surf scoter (Melanitta perspicillata) population that winters in the Pacific Northwest, but whether the uptake occurred on breeding and/or wintering grounds was uncertain for some contaminants. Surf scoters collected in Puget Sound and San Francisco Bay (in another study) during the same period (January 1985) contained similar concentrations of cadmium, but Alsea Bay scoters contained more. Cadmium was inversely related to both liver and body weights of Northwest scoters in January; similar weight losses were reported in experimental laboratory studies. Northwest and north San Francisco Bay scoters contained similar mercury concentrations, but those in south San Francisco Bay contained higher concentrations. San Francisco Bay scoters contained higher arsenic and selenium concentrations than those in the Northwest; however, the 43.4 ppm (geometric mean, dry wt) selenium in livers at Commencement Bay in January was above levels associated with the reproductive problems in aquatic birds at Kesterson National Wildlife Refuge. Even higher concentrations of some elements may be found in surf scoters in March, because a later collection (March) at San Francisco Bay yielded higher concentrations than found there in January. Trace element concentrations in birds at a given wintering location are variable among species and may be influenced by diet, breeding grounds, and physiology (e.g., at Commencement Bay surf scoters with a sediment-associated diet contained 50X more cadmium in their kidneys than did fish-eating western grebes [Aechmophorus occidentalis]). The numerous wildlife species that live on estuaries require further attention.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Northwestern Naturalist","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","usgsCitation":"Henny, C.J., Blus, L.J., Grove, R.A., and Thompson, S., 1991, Accumulation of trace elements and organochlorines by surf scoters wintering in the Pacific northwest: Northwestern Naturalist, v. 72, no. 2, p. 43-60.","productDescription":"43-60","startPage":"43","endPage":"60","numberOfPages":"18","costCenters":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":16312,"rank":200,"type":{"id":11,"text":"Document"},"url":"https://www.jstor.org/stable/3536800","linkFileType":{"id":5,"text":"html"}},{"id":196375,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"72","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4afee4b07f02db6978ba","contributors":{"authors":[{"text":"Henny, Charles J.","contributorId":12578,"corporation":false,"usgs":true,"family":"Henny","given":"Charles","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":337606,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Blus, L. J.","contributorId":38116,"corporation":false,"usgs":true,"family":"Blus","given":"L.","middleInitial":"J.","affiliations":[],"preferred":false,"id":337607,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Grove, R. A.","contributorId":6546,"corporation":false,"usgs":false,"family":"Grove","given":"R.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":337605,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Thompson, S.P.","contributorId":66731,"corporation":false,"usgs":true,"family":"Thompson","given":"S.P.","email":"","affiliations":[],"preferred":false,"id":337608,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":80068,"text":"ofr91594D - 1991 - Part D: Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona","interactions":[],"lastModifiedDate":"2012-02-10T00:11:43","indexId":"ofr91594D","displayToPublicDate":"2007-06-29T00:00:00","publicationYear":"1991","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":"91-594","chapter":"D","title":"Part D: Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona","docAbstract":"Soil sampling surveys were conducted during 1984-1986 across 50 solution-collapse features exposed on the Coconino Plateau of northern Arizona in order to determine whether soil geochemistry can be used to distinguish mineralized breccia pipes from unmineralized collapse features. The 50 sampled features represent the variety of collapse features that crop out on plateau surfaces in northwestern Arizonaoodeeplyorooted solution-collapse breccia pipes, near-surface gypsum collapses, and sinkholes. Of the 50 features that were sampled in this study, 3 are confirmed breccia pipes that contain significant uranium and base-metal minerals, I is believed to be a sinkhole with no economic potential, and 4 are stratabound copper deposits whose possible relationship to breccia pipes is yet to be determined. The remaining collapse features are suspected to overlie breccia pipes, although some of these may represent near surface gypsum collapse features. However, no exploratory drilling results or breccia exposures exist to indicate their underlying structure.\r\n\r\nThe low cost and ease of soil sampling suggested that this technique be evaluated for breccia pipe exploration. This report provides the locations and geochemical results for the soil sampling surveys and brief descriptions of the 50 collapse features. The analytical results of almost 2,000 soil samples are provided in tabular hardcopy and dBase III Plus diskcopy format. The analytical data is provided in digital format to allow the reader to choose their own methods for evaluating the effectiveness of soil sampling over known and suspected breccia pipes.\r\n\r\nA pilot survey conducted over 17 collapse features in 1984 suggested that soil sampling might be useful in distinguishing mineralized breccia pipes from other circular features. Followup detailed surveys in 1985 and 1986 used a radial sampling pattern at each of 50 sites; at least one third of the samples were collected from areas outside of the collapse feature to provide background data. Samples were consistently collected from 3-4 inches depth after the pilot survey showed that metal concentrations were similar in samples from 3-4 inches and 7-8 inches depth.\r\n\r\nThe geochemical analyses of the <80 mesh fractions of the soil samples were performed by the U.S. Geological Survey Analytical Laboratories and Geochemical Services, Inc. The analytical methods applied to these samples by the U.S. Geological Survey laboratories included inductively coupled plasma-atomic emission spectroscopy, X-ray fluorescence spectrometry, neutron activation, atomic absorption, delayed neutron activation, and classical wet chemistry for carbon, fluorine, and sulfur. Geochemical Services, Inc. analyzed the soil samples by inductively coupled plasma emission spectroscopy.","largerWorkType":{"id":18,"text":"Report"},"largerWorkTitle":"Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona","largerWorkSubtype":{"id":5,"text":"USGS Numbered Series"},"language":"ENGLISH","publisher":"Geological Survey (U.S.)","doi":"10.3133/ofr91594D","collaboration":"This research was funded by the U.S. Bureau of Indian Affairs in cooperation with the Hualapai Indian Tribe","usgsCitation":"Van Gosen, B.S., and Wenrich, K.J., 1991, Part D: Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona: U.S. Geological Survey Open-File Report 91-594, Geochemical Data Files on 1 Diskette (5 1/4 in.), https://doi.org/10.3133/ofr91594D.","productDescription":"Geochemical Data Files on 1 Diskette (5 1/4 in.)","costCenters":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"links":[{"id":194588,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"}],"geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -115,34 ], [ -115,37 ], [ -109,37 ], [ -109,34 ], [ -115,34 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b04e4b07f02db698ff4","contributors":{"authors":[{"text":"Van Gosen, Bradley S. 0000-0003-4214-3811 bvangose@usgs.gov","orcid":"https://orcid.org/0000-0003-4214-3811","contributorId":1174,"corporation":false,"usgs":true,"family":"Van Gosen","given":"Bradley","email":"bvangose@usgs.gov","middleInitial":"S.","affiliations":[{"id":387,"text":"Mineral Resources Program","active":true,"usgs":true},{"id":171,"text":"Central Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":291623,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wenrich, Karen J.","contributorId":19177,"corporation":false,"usgs":true,"family":"Wenrich","given":"Karen","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":291624,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":80067,"text":"ofr91594C - 1991 - Part C: Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona","interactions":[],"lastModifiedDate":"2012-02-10T00:11:37","indexId":"ofr91594C","displayToPublicDate":"2007-06-29T00:00:00","publicationYear":"1991","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":"91-594","chapter":"C","title":"Part C: Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona","docAbstract":"Soil sampling surveys were conducted during 1984-1986 across 50 solution-collapse features exposed on the Coconino Plateau of northern Arizona in order to determine whether soil geochemistry can be used to distinguish mineralized breccia pipes from unmineralized collapse features. The 50 sampled features represent the variety of collapse features that crop out on plateau surfaces in northwestern Arizonaoodeeplyorooted solution-collapse breccia pipes, near-surface gypsum collapses, and sinkholes. Of the 50 features that were sampled in this study, 3 are confirmed breccia pipes that contain significant uranium and base-metal minerals, I is believed to be a sinkhole with no economic potential, and 4 are stratabound copper deposits whose possible relationship to breccia pipes is yet to be determined. The remaining collapse features are suspected to overlie breccia pipes, although some of these may represent near surface gypsum collapse features. However, no exploratory drilling results or breccia exposures exist to indicate their underlying structure.\r\n\r\nThe low cost and ease of soil sampling suggested that this technique be evaluated for breccia pipe exploration. This report provides the locations and geochemical results for the soil sampling surveys and brief descriptions of the 50 collapse features. The analytical results of almost 2,000 soil samples are provided in tabular hardcopy and dBase III Plus diskcopy format. The analytical data is provided in digital format to allow the reader to choose their own methods for evaluating the effectiveness of soil sampling over known and suspected breccia pipes.\r\n\r\nA pilot survey conducted over 17 collapse features in 1984 suggested that soil sampling might be useful in distinguishing mineralized breccia pipes from other circular features. Followup detailed surveys in 1985 and 1986 used a radial sampling pattern at each of 50 sites; at least one third of the samples were collected from areas outside of the collapse feature to provide background data. Samples were consistently collected from 3-4 inches depth after the pilot survey showed that metal concentrations were similar in samples from 3-4 inches and 7-8 inches depth.\r\n\r\nThe geochemical analyses of the <80 mesh fractions of the soil samples were performed by the U.S. Geological Survey Analytical Laboratories and Geochemical Services, Inc. The analytical methods applied to these samples by the U.S. Geological Survey laboratories included inductively coupled plasma-atomic emission spectroscopy, X-ray fluorescence spectrometry, neutron activation, atomic absorption, delayed neutron activation, and classical wet chemistry for carbon, fluorine, and sulfur. Geochemical Services, Inc. analyzed the soil samples by inductively coupled plasma emission spectroscopy.","largerWorkType":{"id":18,"text":"Report"},"largerWorkTitle":"Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona","largerWorkSubtype":{"id":5,"text":"USGS Numbered Series"},"language":"ENGLISH","publisher":"Geological Survey (U.S.)","doi":"10.3133/ofr91594C","collaboration":"This research was funded by the U.S. Bureau of Indian Affairs in cooperation with the Hualapai Indian Tribe","usgsCitation":"Van Gosen, B.S., and Wenrich, K.J., 1991, Part C: Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona: U.S. Geological Survey Open-File Report 91-594, Geochemical Data Files on 1 Diskette (5 1/4 in.), https://doi.org/10.3133/ofr91594C.","productDescription":"Geochemical Data Files on 1 Diskette (5 1/4 in.)","costCenters":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"links":[{"id":192852,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"}],"geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -115,34 ], [ -115,37 ], [ -109,37 ], [ -109,34 ], [ -115,34 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b23e4b07f02db6adf48","contributors":{"authors":[{"text":"Van Gosen, Bradley S. 0000-0003-4214-3811 bvangose@usgs.gov","orcid":"https://orcid.org/0000-0003-4214-3811","contributorId":1174,"corporation":false,"usgs":true,"family":"Van Gosen","given":"Bradley","email":"bvangose@usgs.gov","middleInitial":"S.","affiliations":[{"id":171,"text":"Central Mineral and Environmental Resources Science Center","active":true,"usgs":true},{"id":387,"text":"Mineral Resources Program","active":true,"usgs":true}],"preferred":true,"id":291621,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wenrich, Karen J.","contributorId":19177,"corporation":false,"usgs":true,"family":"Wenrich","given":"Karen","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":291622,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":58807,"text":"mf2151 - 1991 - The Use of heavy-mineral concentrate data to show geochemical favorability for zinc-lead-silver and copper-(cobalt) mineral occurrences in the Baird Mountains Quadrangle, northwest Alaska","interactions":[],"lastModifiedDate":"2012-02-10T00:10:14","indexId":"mf2151","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":325,"text":"Miscellaneous Field Studies Map","code":"MF","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"2151","title":"The Use of heavy-mineral concentrate data to show geochemical favorability for zinc-lead-silver and copper-(cobalt) mineral occurrences in the Baird Mountains Quadrangle, northwest Alaska","language":"ENGLISH","doi":"10.3133/mf2151","usgsCitation":"Goldfarb, R., Bailey, E., Folger, P.F., and Schmidt, J., 1991, The Use of heavy-mineral concentrate data to show geochemical favorability for zinc-lead-silver and copper-(cobalt) mineral occurrences in the Baird Mountains Quadrangle, northwest Alaska: U.S. Geological Survey Miscellaneous Field Studies Map 2151, 2 maps on 1 sheet ;44 x 52 cm., sheet 84 x 130 cm., folded in envelope 30 x 24 cm., https://doi.org/10.3133/mf2151.","productDescription":"2 maps on 1 sheet ;44 x 52 cm., sheet 84 x 130 cm., folded in envelope 30 x 24 cm.","costCenters":[],"links":[{"id":105270,"rank":700,"type":{"id":15,"text":"Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_5770.htm","linkFileType":{"id":5,"text":"html"},"description":"5770"},{"id":183911,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"}],"scale":"250000","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -162,67 ], [ -162,68 ], [ -159,68 ], [ -159,67 ], [ -162,67 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ab0e4b07f02db66d643","contributors":{"authors":[{"text":"Goldfarb, R.J.","contributorId":38143,"corporation":false,"usgs":true,"family":"Goldfarb","given":"R.J.","email":"","affiliations":[],"preferred":false,"id":260883,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bailey, E. A.","contributorId":100399,"corporation":false,"usgs":true,"family":"Bailey","given":"E. A.","affiliations":[],"preferred":false,"id":260886,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Folger, P. F.","contributorId":57862,"corporation":false,"usgs":true,"family":"Folger","given":"P.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":260884,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Schmidt, J.M.","contributorId":97916,"corporation":false,"usgs":true,"family":"Schmidt","given":"J.M.","email":"","affiliations":[],"preferred":false,"id":260885,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":26361,"text":"wri904181 - 1991 - Characterization of bottom-sediment, water, and elutriate chemistry at selected stations at Reelfoot Lake, Tennessee","interactions":[],"lastModifiedDate":"2012-02-02T00:08:33","indexId":"wri904181","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"90-4181","title":"Characterization of bottom-sediment, water, and elutriate chemistry at selected stations at Reelfoot Lake, Tennessee","docAbstract":"To better-understand and predict the potential effect of dredging on water quality at Reelfoot Lake, chemical analyses were conducted on samples of lake water, bottom sediment, and elutriate water. Chemical analyses were conducted on samples of lake water, bottom sediment, and elutriate water collected at five stations in the lake during November 1988. Lake water was of the calcium magnesium bicarbonate type with an average dissolved-solids concentration of 120 milligrams per liter. Trace constituents were present in bottom sediments at concentrations representative of their average relative abundance in the earth?s crust. Elutriate waters prepared by mixing bottom sediment and lake water had suspended-solids concentrations as high as 2,000 milligrams per liter which exerted significant oxygen demand Trace constituents in the unfiltered elutriate waters were elevated with respect to lake water; elevated concentrations were attributable to the increased suspended-solids concentrations. Concentrations of total-recoverable copper, lead., and zinc in many elutriate waters exceeded U.S. Environmental Protection Agency?s water-quality criteria for the protection of freshwater aquatic life. The toxicity of elutriate waters, as measured by a 48-hour bioassay with Ceriodaphnia dubia, was low.","language":"ENGLISH","publisher":"U.S. Geological Survey ;\r\nBooks and Open-File Reports Section [distributor],","doi":"10.3133/wri904181","usgsCitation":"Broshears, R.E., 1991, Characterization of bottom-sediment, water, and elutriate chemistry at selected stations at Reelfoot Lake, Tennessee: U.S. Geological Survey Water-Resources Investigations Report 90-4181, iv, 13 p. :map ;28 cm., https://doi.org/10.3133/wri904181.","productDescription":"iv, 13 p. :map ;28 cm.","costCenters":[],"links":[{"id":119118,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/wri_90_4181.jpg"},{"id":2031,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.water.usgs.gov/wri904181/","linkFileType":{"id":5,"text":"html"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49b5e4b07f02db5cb1b2","contributors":{"authors":[{"text":"Broshears, R. 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The 50 sampled features represent the variety of collapse features that crop out on plateau surfaces in northwestern Arizonaoodeeplyorooted solution-collapse breccia pipes, near-surface gypsum collapses, and sinkholes. Of the 50 features that were sampled in this study, 3 are confirmed breccia pipes that contain significant uranium and base-metal minerals, I is believed to be a sinkhole with no economic potential, and 4 are stratabound copper deposits whose possible relationship to breccia pipes is yet to be determined. The remaining collapse features are suspected to overlie breccia pipes, although some of these may represent near surface gypsum collapse features. However, no exploratory drilling results or breccia exposures exist to indicate their underlying structure.\r\n\r\nThe low cost and ease of soil sampling suggested that this technique be evaluated for breccia pipe exploration. This report provides the locations and geochemical results for the soil sampling surveys and brief descriptions of the 50 collapse features. The analytical results of almost 2,000 soil samples are provided in tabular hardcopy and dBase III Plus diskcopy format. The analytical data is provided in digital format to allow the reader to choose their own methods for evaluating the effectiveness of soil sampling over known and suspected breccia pipes.\r\n\r\nA pilot survey conducted over 17 collapse features in 1984 suggested that soil sampling might be useful in distinguishing mineralized breccia pipes from other circular features. Followup detailed surveys in 1985 and 1986 used a radial sampling pattern at each of 50 sites; at least one third of the samples were collected from areas outside of the collapse feature to provide background data. Samples were consistently collected from 3-4 inches depth after the pilot survey showed that metal concentrations were similar in samples from 3-4 inches and 7-8 inches depth.\r\n\r\nThe geochemical analyses of the <80 mesh fractions of the soil samples were performed by the U.S. Geological Survey Analytical Laboratories and Geochemical Services, Inc. The analytical methods applied to these samples by the U.S. Geological Survey laboratories included inductively coupled plasma-atomic emission spectroscopy, X-ray fluorescence spectrometry, neutron activation, atomic absorption, delayed neutron activation, and classical wet chemistry for carbon, fluorine, and sulfur. Geochemical Services, Inc. analyzed the soil samples by inductively coupled plasma emission spectroscopy.","language":"ENGLISH","publisher":"Geological Survey (U.S.)","doi":"10.3133/ofr91594AD","collaboration":"This research was funded by the U.S. Bureau of Indian Affairs in cooperation with the Hualapai Indian Tribe","usgsCitation":"Van Gosen, B.S., and Wenrich, K.J., 1991, Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona: U.S. Geological Survey Open-File Report 91-594, v, 281 p.; 3 Diskettes (5 1/4 in.); A: Discussion (Paper), B-D: Geochemical Data Files (Diskettes), https://doi.org/10.3133/ofr91594AD.","productDescription":"v, 281 p.; 3 Diskettes (5 1/4 in.); A: Discussion (Paper), B-D: Geochemical Data Files (Diskettes)","costCenters":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"links":[{"id":153921,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1991/0594a/report-thumb.jpg"},{"id":91275,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1991/0594a/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -115,34 ], [ -115,37 ], [ -109,37 ], [ -109,34 ], [ -115,34 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b1fe4b07f02db6ab88f","contributors":{"authors":[{"text":"Van Gosen, Bradley S. 0000-0003-4214-3811 bvangose@usgs.gov","orcid":"https://orcid.org/0000-0003-4214-3811","contributorId":1174,"corporation":false,"usgs":true,"family":"Van Gosen","given":"Bradley","email":"bvangose@usgs.gov","middleInitial":"S.","affiliations":[{"id":171,"text":"Central Mineral and Environmental Resources Science Center","active":true,"usgs":true},{"id":387,"text":"Mineral Resources Program","active":true,"usgs":true}],"preferred":true,"id":184111,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wenrich, Karen J.","contributorId":19177,"corporation":false,"usgs":true,"family":"Wenrich","given":"Karen","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":184112,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":20798,"text":"ofr91464 - 1991 - Chemical analysis of water samples and geophysical logs from cored test holes drilled in the central Oklahoma Aquifer, Oklahoma","interactions":[],"lastModifiedDate":"2017-12-06T12:55:35","indexId":"ofr91464","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","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":"91-464","title":"Chemical analysis of water samples and geophysical logs from cored test holes drilled in the central Oklahoma Aquifer, Oklahoma","docAbstract":"Chemical analyses of water from eight test holes and geophysical logs for nine test holes drilled in the Central Oklahoma aquifer are presented. The test holes were drilled to investigate local occurrences of potentially toxic, naturally occurring trace substances in ground water. These trace substances include arsenic, chromium, selenium, residual alpha-particle activities, and uranium. Eight of the nine test holes were drilled near wells known to contain large concentrations of one or more of the naturally occurring trace substances. One test hole was drilled in an area known to have only small concentrations of any of the naturally occurring trace substances.
Water samples were collected from one to eight individual sandstone layers within each test hole. A total of 28 water samples, including four duplicate samples, were collected. The temperature, pH, specific conductance, alkalinity, and dissolved-oxygen concentrations were measured at the sample site. Laboratory determinations included major ions, nutrients, dissolved organic carbon, and trace elements (aluminum, arsenic, barium, beryllium, boron, cadmium, chromium, hexavalent chromium, cobalt, copper, iron, lead, lithium, manganese, mercury, molybdenum, nickel, selenium, silver, strontium, vanadium and zinc). Radionuclide activities and stable isotope (5 values also were determined, including: gross-alpha-particle activity, gross-beta-particle activity, radium-226, radium-228, radon-222, uranium-234, uranium-235, uranium-238, total uranium, carbon-13/carbon-12, deuterium/hydrogen-1, oxygen-18/oxygen-16, and sulfur-34/sulfur-32. Additional analyses of arsenic and selenium species are presented for selected samples as well as analyses of density and iodine for two samples, tritium for three samples, and carbon-14 for one sample.
Geophysical logs for most test holes include caliper, neutron, gamma-gamma, natural-gamma logs, spontaneous potential, long- and short-normal resistivity, and single-point resistance. Logs for test-hole NOTS 7 do not include long- and short-normal resistivity, spontaneous-potential, or single-point resistivity. Logs for test-hole NOTS 7A include only caliper and natural-gamma logs.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Oklahoma City, OK","doi":"10.3133/ofr91464","usgsCitation":"Schlottmann, J.L., and Funkhouser, R.A., 1991, Chemical analysis of water samples and geophysical logs from cored test holes drilled in the central Oklahoma Aquifer, Oklahoma: U.S. Geological Survey Open-File Report 91-464, vi, 58 p., https://doi.org/10.3133/ofr91464.","productDescription":"vi, 58 p.","costCenters":[],"links":[{"id":349776,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1991/0464/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":152694,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1991/0464/report-thumb.jpg"}],"country":"United States","state":"Oklahoma","otherGeospatial":"Central Oklahoma Aquifer","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -97.75,\n 35\n ],\n [\n -96.75,\n 35\n ],\n [\n -96.75,\n 36\n ],\n [\n -97.75,\n 36\n ],\n [\n -97.75,\n 35\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e499fe4b07f02db5bcceb","contributors":{"authors":[{"text":"Schlottmann, Jamie L.","contributorId":8830,"corporation":false,"usgs":true,"family":"Schlottmann","given":"Jamie","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":183264,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Funkhouser, Ron A.","contributorId":58294,"corporation":false,"usgs":true,"family":"Funkhouser","given":"Ron","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":183265,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":20747,"text":"ofr9139 - 1991 - Reconnaissance geochemical survey of the Farah Garan-Kutam mineral belt, Kingdom of Saudi Arabia","interactions":[],"lastModifiedDate":"2015-09-16T14:13:17","indexId":"ofr9139","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","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":"91-39","title":"Reconnaissance geochemical survey of the Farah Garan-Kutam mineral belt, Kingdom of Saudi Arabia","docAbstract":"Wadi-sediment samples were collected from 450 sites in a 580-km2 area (sample density 1.5 per km2) as part of an exploration program designed to assess the mineral potential of the Farah Garan - Kutam mineral belt and to evaluate mineralization at the Farah Garan ancient working (DGMR Project 3.03.10). Demagnetized panned-concentrate and sieved minus-80-mesh fractions were prepared from each bulk sample of approximately 5 kg. The fractions were analyzed for silver, arsenic, copper, lead, and zinc by atomic-absorption methods and for gold by an atomic-absorption graphite-furnace method.
\nThe analytical results for the panned-concentrate samples delineate 21 anomalies, and the results for the minus-80-mesh samples delineate 24. Of the latter, 14 are coincident with panned-concentrate anomaly areas, whereas 10 are uniquely defined. The analytical results of the panned-concentrate samples uniquely define two areas. Overall, the panned-concentrate samples yielded threshold values higher than the threshold values for the minus-80-mesh samples (for gold, 10 times higher), and delineate anomalous areas larger than those for the minus-80-mesh samples. This observation is consistent with the results of similar surveys elsewhere in the Arabian Shield, which indicate that panned-concentrate samples more effectively outline geochemical anomalies than sieved fine-grained samples.
\nIn the present survey, geochemical anomalies locate all the sites of mineralization known from previous work. The survey is therefore technically a success. However, a large number of these anomalies probably result from contamination of the wadi systems by metal dispersed from ancient mine workings, and this particular survey, overall, may be of limited value as a guide to the discovery of hitherto unknown mineralization. Nevertheless, the survey outlines two areas that may mark extensions to known mineralization, and a number of other areas in which no mineralization is known. Based on a consideration of the character of the bedrock geology, the value of each reported analytical result in relation to the respective element thresholds, and the number of anomalous samples that cluster in any given area, four areas are recommended for high-priority follow-up sampling.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ofr9139","usgsCitation":"Samater, R., Johnson, P., and Bookstrom, A., 1991, Reconnaissance geochemical survey of the Farah Garan-Kutam mineral belt, Kingdom of Saudi Arabia: U.S. Geological Survey Open-File Report 91-39, Report: ii, 25 p. :ill.; maps: 28 cm., https://doi.org/10.3133/ofr9139.","productDescription":"Report: ii, 25 p. :ill.; maps: 28 cm.","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":152391,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1991/0039/report-thumb.jpg"},{"id":50302,"rank":400,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/of/1991/0039/plate-1.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":50303,"rank":401,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/of/1991/0039/plate-2.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":50304,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1991/0039/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"country":"Saudi Arabia","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n 43.5,\n 17.5 \n ],\n [\n 43.5,\n 18\n ],\n [\n 44,\n 18\n ],\n [\n 44,\n 17.5 \n ],\n [\n 43.5,\n 17.5\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a73e4b07f02db643c80","contributors":{"authors":[{"text":"Samater, R.M.","contributorId":82694,"corporation":false,"usgs":true,"family":"Samater","given":"R.M.","affiliations":[],"preferred":false,"id":183175,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Johnson, P.R.","contributorId":37332,"corporation":false,"usgs":true,"family":"Johnson","given":"P.R.","email":"","affiliations":[],"preferred":false,"id":183174,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bookstrom, A. A.","contributorId":94681,"corporation":false,"usgs":true,"family":"Bookstrom","given":"A. A.","affiliations":[],"preferred":false,"id":183176,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":20278,"text":"ofr91357 - 1991 - Geophysical logs from a copper oxide deposit, Santa Cruz Project, Casa Grande, Arizona","interactions":[],"lastModifiedDate":"2012-02-02T00:07:40","indexId":"ofr91357","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","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":"91-357","title":"Geophysical logs from a copper oxide deposit, Santa Cruz Project, Casa Grande, Arizona","language":"ENGLISH","publisher":"U.S. Geological Survey,","doi":"10.3133/ofr91357","usgsCitation":"Nelson, P.H., 1991, Geophysical logs from a copper oxide deposit, Santa Cruz Project, Casa Grande, Arizona: U.S. Geological Survey Open-File Report 91-357, iv, 75 p. :ill. ;28 cm., https://doi.org/10.3133/ofr91357.","productDescription":"iv, 75 p. :ill. ;28 cm.","costCenters":[],"links":[{"id":152330,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1991/0357/report-thumb.jpg"},{"id":49812,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1991/0357/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ac8e4b07f02db67bb30","contributors":{"authors":[{"text":"Nelson, Philip H. pnelson@usgs.gov","contributorId":862,"corporation":false,"usgs":true,"family":"Nelson","given":"Philip","email":"pnelson@usgs.gov","middleInitial":"H.","affiliations":[{"id":164,"text":"Central Energy Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":182374,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":18881,"text":"ofr91107B - 1991 - Bibliography of Quaternary geology, Copper River Basin and adjacent areas, south-central Alaska","interactions":[],"lastModifiedDate":"2013-12-06T13:49:50","indexId":"ofr91107B","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","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":"91-107","chapter":"B","title":"Bibliography of Quaternary geology, Copper River Basin and adjacent areas, south-central Alaska","language":"English","publisher":"U.S. Geological Survey ;Books and Open-File Reports Section [distributor],","doi":"10.3133/ofr91107B","collaboration":"The USGS does not support this software or technical questions for the software associated with the publication.","usgsCitation":"Ferrians, O.J., 1991, Bibliography of Quaternary geology, Copper River Basin and adjacent areas, south-central Alaska: U.S. Geological Survey Open-File Report 91-107, 1 Word document, https://doi.org/10.3133/ofr91107B.","productDescription":"1 Word document","costCenters":[],"links":[{"id":150793,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":269629,"type":{"id":4,"text":"Application Site"},"url":"https://pubs.usgs.gov/of/1991/0107b/application.zip"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a51e4b07f02db629903","contributors":{"authors":[{"text":"Ferrians, Oscar J. Jr.","contributorId":42952,"corporation":false,"usgs":true,"family":"Ferrians","given":"Oscar","suffix":"Jr.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":179911,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":18880,"text":"ofr91107A - 1991 - Bibliography of Quaternary geology, Copper River Basin and adjacent areas, south-central Alaska","interactions":[],"lastModifiedDate":"2012-02-02T00:07:27","indexId":"ofr91107A","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1991","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":"91-107","chapter":"A","title":"Bibliography of Quaternary geology, Copper River Basin and adjacent areas, south-central Alaska","language":"ENGLISH","publisher":"U.S. Geological Survey ;\r\nBooks and Open-File Reports Section [distributor],","doi":"10.3133/ofr91107A","usgsCitation":"Ferrians, O.J., 1991, Bibliography of Quaternary geology, Copper River Basin and adjacent areas, south-central Alaska: U.S. Geological Survey Open-File Report 91-107, 20 p. ;28 cm., https://doi.org/10.3133/ofr91107A.","productDescription":"20 p. ;28 cm.","costCenters":[],"links":[{"id":150878,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1991/0107a/report-thumb.jpg"},{"id":48277,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1991/0107a/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a51e4b07f02db629901","contributors":{"authors":[{"text":"Ferrians, Oscar J. Jr.","contributorId":42952,"corporation":false,"usgs":true,"family":"Ferrians","given":"Oscar","suffix":"Jr.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":179910,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70016705,"text":"70016705 - 1991 - Ore microscopy of the Paoli silver-copper deposit, Oklahoma","interactions":[],"lastModifiedDate":"2025-03-20T15:13:51.615019","indexId":"70016705","displayToPublicDate":"1991-05-03T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2954,"text":"Ore Geology Reviews","active":true,"publicationSubtype":{"id":10}},"title":"Ore microscopy of the Paoli silver-copper deposit, Oklahoma","docAbstract":"The Paoli silver-copper deposit is located in south-central Oklahoma, 56 km south-southeast from Norman, Oklahoma. It was mined for high-grade silver-copper near the beginning of this century, and intensive exploratory drilling during the early 1970's delineated unmined portions of the deposit. A collaborative study between the U.S.G.S., the Kansas Geological Survey, and the University of Missouri-Rolla was undertaken to provide new information on the character of red bed copper deposits of the Midcontinent region.
The Paoli deposit has been interpreted to occur as a roll-front type of deposit. The silver and copper mineralization occurs within paleochannels in the Permian Wellington Formation. The silver-copper interfaces appear to be controlled by oxidation-reduction interfaces that are marked by grey to red color changes in the host sandstone. Ore microscopic examinations of polished thin sections show that unoxidized ore consists of chalcocite, digenite, chalcopyrite, covellite and pyrite; and oxidized ores are characterized by covellite, bornite, hematite and goethite. In sandstone-hosted ores, chalcocite and digenite replace dolomite and border clastic quartz grains. In siltstone-hosted ores, the copper sulfide grains have varied shapes; most are irregular in shape and 5–25 μm across, others have euhedral shapes suggestive of pyrite crystal replacements, and some are crudely spherical and are 120–200 μm across. Chalcopyrite is the predominant copper sulfide at depth. Covellite and malachite replace chalcocite and digenite near the surface.
Silver only occurs as native silver; most as irregularly shaped grains 40–80 μm across, but some as cruciform crystals that are up to 3.5 mm across. The native silver has been deposited after copper sulfides, and locally replaces chalcocite.
Surficial nodules of pyrite, malachite and hematite locally are present in outcrops at the oxidation-reduction fronts. Polished sections of the nodules show that malachite forms a cement around quartz sand grains, and brecciated pyrite grains are surrounded by rims of hematite and goethite. Dolomite is the principal sandstone cement. Cathodoluminescence microscopic study of the mineral has shown that it was deposited during seven periods before the copper sulfide mineralization.
","language":"English","publisher":"Elsevier","doi":"10.1016/0169-1368(91)90024-2","usgsCitation":"Thomas, C., Hagni, R., and Berendsen, P., 1991, Ore microscopy of the Paoli silver-copper deposit, Oklahoma: Ore Geology Reviews, v. 6, no. 2-3, p. 229-244, https://doi.org/10.1016/0169-1368(91)90024-2.","productDescription":"16 p.","startPage":"229","endPage":"244","costCenters":[],"links":[{"id":224698,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Oklahoma","city":"Paoli","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -97.30989669582416,\n 34.856450315481666\n ],\n [\n -97.30989669582416,\n 34.80414468979322\n ],\n [\n -97.21983169312097,\n 34.80414468979322\n ],\n [\n -97.21983169312097,\n 34.856450315481666\n ],\n [\n -97.30989669582416,\n 34.856450315481666\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"6","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6f6ee4b0c8380cd75ab9","contributors":{"authors":[{"text":"Thomas, C.A.","contributorId":14385,"corporation":false,"usgs":true,"family":"Thomas","given":"C.A.","email":"","affiliations":[],"preferred":false,"id":374260,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hagni, R.D.","contributorId":33064,"corporation":false,"usgs":true,"family":"Hagni","given":"R.D.","email":"","affiliations":[],"preferred":false,"id":374261,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Berendsen, P.","contributorId":68037,"corporation":false,"usgs":true,"family":"Berendsen","given":"P.","affiliations":[],"preferred":false,"id":374262,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70016761,"text":"70016761 - 1991 - Crustal structure of accreted terranes in southern Alaska, Chugach Mountains and Copper River Basin, from seismic refraction results","interactions":[],"lastModifiedDate":"2020-05-07T13:43:45.259869","indexId":"70016761","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2312,"text":"Journal of Geophysical Research","active":true,"publicationSubtype":{"id":10}},"title":"Crustal structure of accreted terranes in southern Alaska, Chugach Mountains and Copper River Basin, from seismic refraction results","docAbstract":"Seismic refraction data were collected along a 320-km-long \"transect' line in southern Alaska, crossing the Prince William, Chugach, Peninsular, and Wrangellia terranes, and along several shorter lines within individual terranes. Velocity structure in the upper crust (less than 9-km depth) differs among the four terranes. In contrast, layers in the middle crust (9- to 25-km depth) in some case extend across projected terrane boundaries. The top of a gently north dipping sequence of low- and high-velocity layers (5.7-7.8 km/s), more than 10 km thick, extends from near the surface in the southern Chugach terrane to more than 20-km depth beneath the southern Peninsular terrane. This sequence, truncated by the suture between the Prince William and Chugach terranes, is interpreted to be an underplated \"terrane' made up of fragments of the Kula plate and its sedimentary overburden that were accreted during subduction in the late Mesozoic and/or early Tertiary, during or between times of accretion of the Prince William and Chugach terranes.
","largerWorkTitle":"","language":"English","publisher":"AGU","doi":"10.1029/90JB02316","issn":"01480227","usgsCitation":"Fuis, G., Ambos, E.L., Mooney, W.D., Christensen, N., and Geist, E., 1991, Crustal structure of accreted terranes in southern Alaska, Chugach Mountains and Copper River Basin, from seismic refraction results: Journal of Geophysical Research, v. 96, no. B3, p. 4187-4227, https://doi.org/10.1029/90JB02316.","productDescription":"41 p.","startPage":"4187","endPage":"4227","numberOfPages":"41","costCenters":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"links":[{"id":224847,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Alaska","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -155.126953125,\n 58.722598828043374\n ],\n [\n -140.625,\n 58.722598828043374\n ],\n [\n -140.625,\n 63.430860212678105\n ],\n [\n -155.126953125,\n 63.430860212678105\n ],\n [\n -155.126953125,\n 58.722598828043374\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"96","issue":"B3","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"5059fcebe4b0c8380cd4e4fb","contributors":{"authors":[{"text":"Fuis, G. S.","contributorId":83131,"corporation":false,"usgs":true,"family":"Fuis","given":"G. S.","affiliations":[],"preferred":false,"id":374430,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ambos, E. L.","contributorId":23957,"corporation":false,"usgs":true,"family":"Ambos","given":"E.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":374426,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mooney, Walter D. 0000-0002-5310-3631 mooney@usgs.gov","orcid":"https://orcid.org/0000-0002-5310-3631","contributorId":3194,"corporation":false,"usgs":true,"family":"Mooney","given":"Walter","email":"mooney@usgs.gov","middleInitial":"D.","affiliations":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"preferred":true,"id":374429,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Christensen, N.I.","contributorId":28016,"corporation":false,"usgs":true,"family":"Christensen","given":"N.I.","email":"","affiliations":[],"preferred":false,"id":374427,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Geist, E.","contributorId":47535,"corporation":false,"usgs":true,"family":"Geist","given":"E.","email":"","affiliations":[],"preferred":false,"id":374428,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70016545,"text":"70016545 - 1991 - The last interglaciation in Alaska: Stratigraphy and paleoecology of potential sites","interactions":[],"lastModifiedDate":"2013-03-25T16:27:15","indexId":"70016545","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3217,"text":"Quaternary International","active":true,"publicationSubtype":{"id":10}},"title":"The last interglaciation in Alaska: Stratigraphy and paleoecology of potential sites","docAbstract":"At least 20 localities in Alaska contain deposits that may provide information on the last interglaciation (Oxygen-Isotope Substage 5e). These widely dispersed localities include river bluffs, coastal bluffs and terraces, elevated marine shorelines, lake basins, and artificial excavations. Most of the inferred interglacial deposits contain macrofossils or pollen that are older than the range of radiocarbon dating and commonly indicate climate as warm as or warmer than the present. At a few localities, evidence for deep thaw of permafrost also indicates a warm paleoclimate. At eight localities, the Old Crow tephra occurs at or below organic deposits that may represent Substage 5e. The tephra occurs beneath conspicuous organic deposits at Fairbanks, the Yukon Palisades, and Holitna lowland, and directly above a peat bed at Hogatza Mine. At Birch Creek, Halfway House, Ky-11, and Imuruk Lake, the tephra occurs within a paleosol or organic deposit, but other organic horizons that more likely indicate interglacial conditions occur at higher stratigraphic levels. The varied stratigraphic relations of the Old Crow tephra suggest that it may have been deposited close to the boundary between Isotope Substages 6 and 5, which is dated at about 130 ka in the marine record and between 132 and 140 ka on land. These age relations suggests that the tephra may have been deposited about 135 ?? 5 ka, validating the recent fission-track age determination of 140 ?? 10 ka for this deposit. Six coastal localities contain deposits of probable interglacial age, and these commonly are associated with evidence for eustatic sea levels higher than those of the present. Beach and sublittoral sediments of the Pelukian transgression occur up to 12 m asl along the northwest coast of Alaska, and are correlative with barrier island and lagoonal sediments on the Alaskan Arctic Coastal Plain. Both sets of deposits commonly contain extralimital mollusks and microfauna that indicate marine water slightly warmer than present and suggest that seasonal sea ice did not extend south of Bering Strait during the last interglacial as it does today. Farther south, elevated marine-terrace deposits on Amchitka Island contain marine invertebrates that indicate a climate warmer than at present. Peat horizons in coastal exposure at Goose Bay and coastal terraces at Lituya Bay contain pollen spectra that suggest forests like those of the present day, and spruce macrofossils exposed on Baldwin Peninsula indicate boreal forest more extensive than at present. Sediments from several lakes in northwestern Alaska may contain continuous records of the last interglaciation. A major warm interval, possibly Isotope Substage 5e, has been identified in a core from Squirrel Lake by a peak in Picea pollen that indicates forest extension beyond present limits. Similar pollen records are potentially available from two maars which formed in the Cape Espenberg area more than 125 ka. Terrestrial organic deposits thought to record the last interglaciation occur interstratified with marine and glaciogenic sediments in the Nushagak Lowland of southwest Alaska and on Baldwin Peninsula in Kotzebue Sound. Extensive exposures along the Copper and Nenana Rivers may also contain organic deposits that record the last interglaciation. ?? 1992.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Quaternary International","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","doi":"10.1016/1040-6182(91)90040-U","issn":"10406182","usgsCitation":"Hamilton, T.D., and Brigham-Grette, J., 1991, The last interglaciation in Alaska: Stratigraphy and paleoecology of potential sites: Quaternary International, v. 10-12, no. C, p. 49-71, https://doi.org/10.1016/1040-6182(91)90040-U.","startPage":"49","endPage":"71","numberOfPages":"23","costCenters":[],"links":[{"id":223532,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":270038,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/1040-6182(91)90040-U"}],"volume":"10-12","issue":"C","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bad84e4b08c986b323c73","contributors":{"authors":[{"text":"Hamilton, T. D.","contributorId":36921,"corporation":false,"usgs":true,"family":"Hamilton","given":"T.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":373858,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Brigham-Grette, J.","contributorId":78869,"corporation":false,"usgs":true,"family":"Brigham-Grette","given":"J.","affiliations":[],"preferred":false,"id":373859,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70014903,"text":"70014903 - 1991 - On plate tectonics and the geologic evolution of southwestern North America","interactions":[],"lastModifiedDate":"2024-05-03T13:32:22.905282","indexId":"70014903","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2312,"text":"Journal of Geophysical Research","active":true,"publicationSubtype":{"id":10}},"title":"On plate tectonics and the geologic evolution of southwestern North America","docAbstract":"Very rapid subduction of the Farallon plate under southwestern North America between 60 and 40 Ma was accompanied by a relatively low volume of magmatism throughout the southwestern United States and northern Mexico. Between 40 and 20 Ma, when subduction slowed significantly and in one area may have even stopped, magmatism became widespread and voluminous from Nevada and Utah to central Mexico. This correlation of rapid subduction with a relatively low volume of magmatism can be explained by the observation that subduction-related andesitic arc volcanism, often formed in a Laramide-style compressional regime, is relatively low volume compared to continental volcanism. The shallow roots of arc volcanic systems are clearly exposed in the porphyry copper deposits found in currently active arcs and common throughout southwestern North America between 60 and 50 Ma. By 43 Ma, worldwide plate motions changed, the Pacific plate began moving away from North America, and subduction of the Farallon plate slowed. By around 36 Ma, the easternmost part of the East Pacific Rise, which was located between the Pioneer and Murray fracture zones, approached the trench and the young, hot, buoyant lithosphere appears to have clogged part of the subduction zone. Uplift on land became widespread. Voluminous continental magmatism formed the Sierra Madre Occidental (SMO) of Mexico, one of the largest batholiths in the world, as well as volcanic centers now exposed in the San Juan Mountains of Colorado and the Rio Grande Rift of New Mexico. Vectors of motion of the Pacific plate relative to the North American plate determined by Stock and Molnar (1988) are consistent with formation of a transtensional environment along the plate boundary sufficient to create a 100- to 200-km-wide void just landward of the old volcanic arc. While the SMO batholith was forming within this void, the Monterey and Arguello microplates just offshore to the west were broken off from the Farallon plate and rotated so that the East Pacific Rise in this immediate area became nearly perpendicular to the trench and perpendicular to the vector of motion of the Pacific plate relative to North America. Formation of the SMO batholith was followed between 24 and 20 Ma by a major increase in the rate of subduction of the Guadalupe plate, a fragment of the former Farallon plate, and by increasing mylonitization, extension, and uplift in the metamorphic core complexes that extend northwestward through southern Arizona from the northern end of the SMO batholith. The plate margin underwent another major change between 12.5 and 10 Ma when subduction again stopped, strike slip faulting became dominant along the coast, the Basin and Range Province opened, and numerous tectonostratigraphic terranes in southern California underwent large rotations. By 3 Ma a large, new terrane had been severed from North America immediately west of the SMO batholith as the Gulf of California opened. These observations can be explained by a model for the weakening and ultimate falling apart of the uppermost part of the subducted oceanic plate in the 20–30 m.y. after the end of rapid subduction. As the plate falls apart, not only is compressional stress relieved, but significant backslip along the old subduction zone is also possible, perhaps bringing blueschists rapidly upward from 20- to 30-km depths.
One of the most important results of the Trans-Alaska Crustal Transect investigations is the discovery that more than one third of the North American plate in southern Alaska (Chugach Mountains and Copper River basin) consists of tectonically underplated oceanic lithosphere. In southern Alaska, exposed accreted tectonostratigraphic terranes, include, from south to north along the transect, the Prince William, Chugach, Peninsular, and Wrangellia terranes. Chief results from seismic refraction data include the following: (1) A sequence of layers of low and high velocity (5.7–7.8 km/s), more than 10 km thick, dips gently northward, with its top at the surface in the southernmost Chugach terrane and at more than 20-km depth beneath the southern Peninsular terrane. A high-velocity layer at the top of this sequence corresponds to metabasalt in the southernmost Chugach terrane. This sequence is interpreted to be tectonically underplated fragments of the Kula plate and its sedimentary overburden. (2) An intermediate-velocity layer (6.35–6.5 km/s) at 9-km depth beneath both the northern Chugach and southern Peninsular terranes appears to extend without offset across the deep projection of the suture between these two terranes, the Border Ranges fault system. (3) A crustal “root” between depths of 19 and 57 km beneath the northern Peninsular and Wrangellia terranes appears to extend without offset across the deep projection of the suture between these two terranes, the West Fork fault system. This crustal root also appears to abut the tectonically underplated sequence to the south. Unfortunately, in results 2 and 3 the apparent crosscutting and abutting relationships can not be unambiguously resolved. Three scenarios, A, B, and C, have been offered to explain the evolution of this structure. Scenarios A and B differ in interpretation of the depth extent of the northern Chugach and southern Peninsular terranes. In scenario A these terranes extend to only 9-km depth, where they rest on an unknown middle crust, interpreted as a deeper part of the Peninsular terrane. In this scenario, the northern Chugach and southern Peninsular terrenes moved landward as a tectonic wedge, during tectonic underplating in the latest Cretaceous or early Tertiary, and uplifted the upper crust of the Peninsular terrane to the north. In scenario B, the northern Chugach and southern Peninsular terranes extend to 20-km depth. In this scenario, they were compressed but not detached and displaced during accretion. Scenarios A, B, and C differ in interpretation of the deep crustal root that appears to abut the tectonically underplated sequence. Since the Peninsular and Wrangellia terranes were at or below sea level prior to the mid-Cretaceous, the root was probably emplaced in mid-Cretaceous or younger times. In scenario A the root is lower crust of North America that moved southward during tectonic underplating of the Kula plate. In scenario B the root is, in part, tectonically underplated rocks similar to the Kula plate sequence to the south. In scenario C the root is, in part, magmatically underplated rocks.