Most of the Tertiary section on Sierra Leone Rise off northwest Africa consists of chalk, marl, and limestone that show cyclic alterations of clay-rich and clay-poor beds about 20–60 cm thick. On the basis of biostratigraphic accumulation rates, the cycles in Oligocene and Miocene chalk have periods which average about 44,000 years, and those in Eocene siliceous limestone have periods of 4000–27,000 years. Several sections were sampled in detail to further define the cycles in terms of content of CaCO3, clay minerals, and relative abundances of calcareous nannofossils. Extending information gained by analyses of Pleistocene cores from the continental margin of northwest Africa to the Tertiary cycles on Sierra Leone Rise, both dilution by noncarbonate material and dissolution of CaCO3 could have contributed to the observed relative variations in clay and CaCO3. However, dissolution of CaCO3 as the main cause of the carbonate-clay cycles on the Sierra Leone Rise, rather than dilution by clay, is suggested by the large amount of change (several thousand percent) in terrigenous influx required to produce the observed variations in amount of clay and by the marked increase in abundance of dissolution-resistant discoasters relative to more easily dissolved coccoliths in low-carbonate parts of cycles. The main cause of dissolution of CaCO3 was shoaling of the carbonate compensation depth (CCD) during the early Neogene and climatically induced fluctuations in the thickness of Antarctic Bottom Water.
","language":"English","publisher":"Elsevier","doi":"10.1016/0025-3227(81)90029-3","usgsCitation":"Dean, W.E., Gardner, J., and Cepek, P., 1981, Tertiary carbonate-dissolution cycles on the Sierra Leone Rise, eastern equatorial Atlantic Ocean: Marine Geology, v. 39, no. 1-2, p. 81-101, https://doi.org/10.1016/0025-3227(81)90029-3.","productDescription":"21 p.","startPage":"81","endPage":"101","costCenters":[],"links":[{"id":222512,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"39","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba56ee4b08c986b320a4a","contributors":{"authors":[{"text":"Dean, Walter E. dean@usgs.gov","contributorId":1801,"corporation":false,"usgs":true,"family":"Dean","given":"Walter","email":"dean@usgs.gov","middleInitial":"E.","affiliations":[{"id":318,"text":"Geosciences and Environmental Change Science Center","active":true,"usgs":true}],"preferred":true,"id":362571,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gardner, James V.","contributorId":61769,"corporation":false,"usgs":true,"family":"Gardner","given":"James V.","affiliations":[],"preferred":false,"id":362570,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Cepek, P.","contributorId":39523,"corporation":false,"usgs":true,"family":"Cepek","given":"P.","email":"","affiliations":[],"preferred":false,"id":362569,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70182487,"text":"70182487 - 1981 - Reproduction and early life history of fishes in a cooling lake","interactions":[],"lastModifiedDate":"2017-02-23T12:31:50","indexId":"70182487","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":21,"text":"Thesis"},"publicationSubtype":{"id":28,"text":"Thesis"},"title":"Reproduction and early life history of fishes in a cooling lake","docAbstract":"No abstract available
","language":"English","publisher":"University of Wisconsin","publisherLocation":"Madison, WI","usgsCitation":"Rondorf, D., 1981, Reproduction and early life history of fishes in a cooling lake.","costCenters":[{"id":654,"text":"Western Fisheries Research Center","active":true,"usgs":true}],"links":[{"id":336098,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"publicComments":"Master's Thesis","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58b002dde4b01ccd54fb2825","contributors":{"authors":[{"text":"Rondorf, D.W.","contributorId":80789,"corporation":false,"usgs":true,"family":"Rondorf","given":"D.W.","email":"","affiliations":[{"id":654,"text":"Western Fisheries Research Center","active":true,"usgs":true}],"preferred":false,"id":671247,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012007,"text":"70012007 - 1981 - Aeromagnetic and radio echo ice-sounding measurements over the Dufek intrusion, Antarctica","interactions":[],"lastModifiedDate":"2024-07-16T15:37:43.971318","indexId":"70012007","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":6453,"text":"Journal of Geophysical Research Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Aeromagnetic and radio echo ice-sounding measurements over the Dufek intrusion, Antarctica","docAbstract":"A combined aeromagnetic and radio echo ice-sounding survey (4200 km of traverse) made in 1978 in Antarctica over the Dufek layered mafic intrusion of Jurassic age suggests a minimum area of about 50,000 km2, making it comparable in size with the Bushveld Complex of Africa. Comparisons of the magnetic and subglacial topographic profiles illustrate the usefulness of this combination of methods in studying bedrock geology beneath ice-covered areas. Rocks are exposed in only 3% of the inferred area of the intrusion. Magnetic anomalies measured a few hundred meters above outcrops of the intrusion range in peak-to-trough amplitude from ∼50 nT over the lowermost exposed portion of the section in the Dufek Massif to ∼3600 nT over the uppermost part of the section in the Forrestal Range. Theoretical magnetic anomalies, computed from models based on the subice topography fitted to the highest-amplitude observed magnetic anomalies, required normal and reversed magnetizations ranging from 10−4 to 10−2 emu/cm3 having directions and magnetizations consistent with measurements previously made on oriented samples. This result is interpreted as indicating that the Dufek intrusion cooled through the Curie isotherm during one or more reversals of the earth's magnetic field.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB04p03014","issn":"01480227","usgsCitation":"Behrendt, J.C., Drewry, D., Jankowski, E., and Grim, M.S., 1981, Aeromagnetic and radio echo ice-sounding measurements over the Dufek intrusion, Antarctica: Journal of Geophysical Research Solid Earth, v. 86, no. B4, p. 3014-3020, https://doi.org/10.1029/JB086iB04p03014.","productDescription":"7 p.","startPage":"3014","endPage":"3020","numberOfPages":"7","costCenters":[],"links":[{"id":480578,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/jb086ib04p03014","text":"Publisher Index Page"},{"id":222177,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"B4","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"5059e72ee4b0c8380cd478b2","contributors":{"authors":[{"text":"Behrendt, John C. jbehrendt@usgs.gov","contributorId":25945,"corporation":false,"usgs":true,"family":"Behrendt","given":"John","email":"jbehrendt@usgs.gov","middleInitial":"C.","affiliations":[{"id":213,"text":"Crustal Imaging and Characterization Team","active":false,"usgs":true},{"id":218,"text":"Denver Federal Center","active":false,"usgs":true}],"preferred":false,"id":362505,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Drewry, D.J.","contributorId":41968,"corporation":false,"usgs":true,"family":"Drewry","given":"D.J.","email":"","affiliations":[],"preferred":false,"id":362506,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Jankowski, E.","contributorId":7420,"corporation":false,"usgs":true,"family":"Jankowski","given":"E.","email":"","affiliations":[],"preferred":false,"id":362504,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Grim, M. S.","contributorId":102884,"corporation":false,"usgs":true,"family":"Grim","given":"M.","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":362507,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70195288,"text":"70195288 - 1981 - Toxicity of six bird control chemicals to aquatic organisms ","interactions":[],"lastModifiedDate":"2018-02-07T13:37:40","indexId":"70195288","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1103,"text":"Bulletin of Environmental Contamination and Toxicology","active":true,"publicationSubtype":{"id":10}},"title":"Toxicity of six bird control chemicals to aquatic organisms ","docAbstract":"The U.S. Fish and Wildlife Service (FWS) has supported research on control methods for nuisance birds, mammals, plants, and fish. Although chemical agents have shown great promise, resource managers and regulatory agencies must be assured that these materials are safe to man and the environment. Standardized toxicity tests are conducted to demonstrate the effectiveness of candidate compounds on target organisms and their safety to nontarget organisms (LENNON 1967).
","language":"English","publisher":"Springer","doi":"10.1007/BF01622160","usgsCitation":"Marking, L.L., and Chandler, J.H., 1981, Toxicity of six bird control chemicals to aquatic organisms : Bulletin of Environmental Contamination and Toxicology, v. 26, no. 1, p. 705-716, https://doi.org/10.1007/BF01622160.","productDescription":"12 p.","startPage":"705","endPage":"716","costCenters":[],"links":[{"id":351275,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"26","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5a7c1e7de4b00f54eb229364","contributors":{"authors":[{"text":"Marking, L. L.","contributorId":90661,"corporation":false,"usgs":true,"family":"Marking","given":"L.","middleInitial":"L.","affiliations":[],"preferred":false,"id":727753,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chandler, J. H. Jr.","contributorId":74333,"corporation":false,"usgs":true,"family":"Chandler","given":"J.","suffix":"Jr.","middleInitial":"H.","affiliations":[],"preferred":false,"id":727754,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70011767,"text":"70011767 - 1981 - Regional geochemical studies in the Patagonia Mountains, Santa Cruz County, Arizona","interactions":[],"lastModifiedDate":"2025-04-09T16:37:07.769964","indexId":"70011767","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2302,"text":"Journal of Geochemical Exploration","active":true,"publicationSubtype":{"id":10}},"title":"Regional geochemical studies in the Patagonia Mountains, Santa Cruz County, Arizona","docAbstract":"The Patagonia Mountains in southern Arizona contain the deeply buried porphyry copper system at Red Mountain as well as a number of other base- and precious-metal mines and prospects. The range contains complex Basin and Range geology with units ranging in age from Precambrian to Holocene. Rock types present include igneous intrusive and extrusive units as well as sedimentary and metamorphic units, most of which have been tectonically disturbed. A total of 264 stream-sediment samples were collected and analyzed for 32 elements. Geochemical maps for Sb, Ag, Pb, Te, B, Mn, Au, Zn, Cu (total), Cu (cold-extractable), and Mo, as well as for Cu (cold-extractable)/Cu (total) and Fe/Mn, are presented.
Anomaly patterns for these elements generally occur over the Red Mountain deposit and (or) along a north-northwest trend parallel to the major Harshaw Creek Fault. Much of the entire area sampled contains widespread anomalies for Pb, Te, and Cu; the other elements are only locally anomalous. Various plots of ratios of Cu (cold-extractable) to Cu (total) did not produce any new information not readily apparent on either one of the two copper maps. A plot of ratios of Fe to Mn delineated many areas of pyrite mineralization. Several of these areas may represent the pyritic halos around deeply buried porphyry copper systems.
The best ore guide for the Red Mountain porphyry system is the coincidence of positive anomalies of Mo, Pb, and Te and a negative anomaly of Mn. Other areas with anomalies of the same suite of elements are present within the Patagonia Mountains.
It is concluded that geochemical sampling, even in a highly contaminated area, can be useful in delineating major geologic features, such as porphyry copper belts and major faults. Multielement geochemical surveys on a regional scale can effectively locate large, deeply buried, zoned mineral systems such as that at Red Mountain. Plots of element ratios, where adequately understood, can provide geochemical information not readily discernible from plots of single elements alone.
","language":"English","publisher":"Elsevier","doi":"10.1016/0375-6742(81)90109-6","usgsCitation":"Chaffee, M., Hill, R.H., Sutley, S.J., and Watterson, J., 1981, Regional geochemical studies in the Patagonia Mountains, Santa Cruz County, Arizona: Journal of Geochemical Exploration, v. 14, p. 135-153, https://doi.org/10.1016/0375-6742(81)90109-6.","productDescription":"19 p.","startPage":"135","endPage":"153","costCenters":[],"links":[{"id":221469,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arizona","county":"Santa Cruz County","otherGeospatial":"Patagonia Mountains","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -110.77118066380213,\n 31.530102783773245\n ],\n [\n -110.77118066380213,\n 31.336014014639815\n ],\n [\n -110.63864115062256,\n 31.336014014639815\n ],\n [\n -110.63864115062256,\n 31.530102783773245\n ],\n [\n -110.77118066380213,\n 31.530102783773245\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"14","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"50e4a4dbe4b0e8fec6cdbcab","contributors":{"authors":[{"text":"Chaffee, M.A.","contributorId":108049,"corporation":false,"usgs":true,"family":"Chaffee","given":"M.A.","affiliations":[],"preferred":false,"id":361914,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hill, R. H.","contributorId":57059,"corporation":false,"usgs":true,"family":"Hill","given":"R.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":361911,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Sutley, S. J.","contributorId":91484,"corporation":false,"usgs":true,"family":"Sutley","given":"S.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":361912,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Watterson, J.R.","contributorId":102890,"corporation":false,"usgs":true,"family":"Watterson","given":"J.R.","email":"","affiliations":[],"preferred":false,"id":361913,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70011775,"text":"70011775 - 1981 - Variations in stable- isotope ratios of ground waters in seismically active regions of California","interactions":[],"lastModifiedDate":"2024-02-15T01:20:20.009952","indexId":"70011775","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1807,"text":"Geophysical Research Letters","active":true,"publicationSubtype":{"id":10}},"title":"Variations in stable- isotope ratios of ground waters in seismically active regions of California","docAbstract":"Measurements of D and 18O concentrations of ground waters in seismically active regions are potentially useful in earthquake prediction and in elucidating mechanisms operative during earthquakes. Principles of this method are discussed and some preliminary data regarding a magnitude 5.7 earthquake at the Oroville Dam in 1975 and a series of events near San Juan Bautista in 1980 are presented to support the utility of such measurements. After earthquakes, the D content of nearby ground waters increased by several permil while the 18O content remained constant. This increase implies that H2O may have either decomposed or reacted to form molecular H2 at depth. It is emphasized that many areas must be investigated for these effects in order to find a sufficient number of \"sensitive\" water wells and springs to permit a truly effective program of earthquake research.
No abstract available.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB11p10131","issn":"01480227","usgsCitation":"Barker, F., 1981, Introduction to special issue on granites and rhyolites: A commentary for the nonspecialist: Journal of Geophysical Research Solid Earth, v. 86, no. B11, p. 10131-10135, https://doi.org/10.1029/JB086iB11p10131.","productDescription":"5 p.","startPage":"10131","endPage":"10135","numberOfPages":"5","costCenters":[],"links":[{"id":221546,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a3df1e4b0c8380cd63985","contributors":{"authors":[{"text":"Barker, F.","contributorId":101368,"corporation":false,"usgs":true,"family":"Barker","given":"F.","affiliations":[],"preferred":false,"id":361929,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70011711,"text":"70011711 - 1981 - The earliest seeds","interactions":[],"lastModifiedDate":"2012-03-12T17:18:32","indexId":"70011711","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2840,"text":"Nature","active":true,"publicationSubtype":{"id":10}},"title":"The earliest seeds","docAbstract":"Lagenostomalean-type seeds in bifurcating cupule systems have been discovered in the late Devonian Hampshire Formation of Randolph County, West Virginia, USA (Fig. 1). The associated megaflora, plants from coal balls, and vertebrate and invertebrate faunas demonstrate that the material is Famennian; the microflora indicates a more specific Fa2c age. Consequently, these seeds predate Archaeosperma arnoldii1 from the Fa2d of northeastern Pennsylvania, the oldest previously reported seed. By applying precision fracture, transfer, de??gagement, and thin-section techniques to selected cupules from the more than 100 specimens on hand, we have determined the three-dimensional morphology and histology of the seeds (Fig. 2a-h, k) and cupule systems. A comparison with known late Devonian to early Carboniferous seeds reveals that ours are more primitively organized than all except Genomosperma2,3. ?? 1981 Nature Publishing Group.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Nature","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1038/293462a0","issn":"00280836","usgsCitation":"Gillespie, W., Rothwell, G., and Scheckler, S., 1981, The earliest seeds: Nature, v. 293, no. 5832, p. 462-464, https://doi.org/10.1038/293462a0.","startPage":"462","endPage":"464","numberOfPages":"3","costCenters":[],"links":[{"id":221460,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205125,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1038/293462a0"}],"volume":"293","issue":"5832","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baaece4b08c986b322ad7","contributors":{"authors":[{"text":"Gillespie, W.H.","contributorId":10804,"corporation":false,"usgs":true,"family":"Gillespie","given":"W.H.","email":"","affiliations":[],"preferred":false,"id":361781,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rothwell, G.W.","contributorId":89283,"corporation":false,"usgs":true,"family":"Rothwell","given":"G.W.","email":"","affiliations":[],"preferred":false,"id":361783,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Scheckler, S.E.","contributorId":82847,"corporation":false,"usgs":true,"family":"Scheckler","given":"S.E.","email":"","affiliations":[],"preferred":false,"id":361782,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70011762,"text":"70011762 - 1981 - U-Th-Pb systematics of some granitoids from the northeastern Yilgarn Block, Western Australia and implications for uranium source rock potential","interactions":[],"lastModifiedDate":"2024-02-15T15:24:21.414345","indexId":"70011762","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":6005,"text":"Journal of the Geological Society of Australia","onlineIssn":"0016-7614","active":false,"publicationSubtype":{"id":10}},"title":"U-Th-Pb systematics of some granitoids from the northeastern Yilgarn Block, Western Australia and implications for uranium source rock potential","docAbstract":"The Mount Boreas‐type granite and spatially associated syenitic granitoid of Western Australia yield Pb‐Pb ages of 2370 ± 100 Ma and 2760 ± 210 Ma, respectively. Th‐Pb ages, although less precise, are concordant with these ages, and therefore the apparent ages are interpreted to be the crystallisation ages for these two units. U‐Pb ages are variable and for the most part anomalously old, which suggests a Cainozoic uranium loss. However, this loss is generally small (< 3μg/g); therefore, neither granitoid in its fresh state provides a good source for nearby calcrete‐hosted uranium deposits. The possibility remains that the Mount Boreas‐type granite that has been completely weathered during the Tertiary could have been a source for the calcrete‐type uranium deposits in W.A. Although the Mount Boreas‐type granite is highly fractionated, it does not bear a strong geochemical imprint of a sedimentary precursor. This feature contrasts it with apparently fresh granitoids from other parts of the world that have lost large amounts of uranium (∼ 20μg/g) and are associated with large roll‐type and other low temperature‐type uranium deposits.
","language":"English","publisher":"Taylor & Francis","doi":"10.1080/00167618108729175","usgsCitation":"Stuckless, J., Bunting, J., and Nkomo, I.T., 1981, U-Th-Pb systematics of some granitoids from the northeastern Yilgarn Block, Western Australia and implications for uranium source rock potential: Journal of the Geological Society of Australia, v. 28, no. 3-4, p. 365-375, https://doi.org/10.1080/00167618108729175.","productDescription":"11 p.","startPage":"365","endPage":"375","numberOfPages":"11","costCenters":[],"links":[{"id":221388,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"28","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb9dfe4b08c986b327e88","contributors":{"authors":[{"text":"Stuckless, J. S.","contributorId":6060,"corporation":false,"usgs":true,"family":"Stuckless","given":"J. S.","affiliations":[],"preferred":false,"id":361901,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bunting, J.A.","contributorId":16836,"corporation":false,"usgs":true,"family":"Bunting","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":361902,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Nkomo, Ignatius T.","contributorId":61044,"corporation":false,"usgs":true,"family":"Nkomo","given":"Ignatius","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":361903,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70011757,"text":"70011757 - 1981 - U-Pb isotope systematics and age of uranium mineralization, Midnite mine, Washington.","interactions":[{"subject":{"id":23767,"text":"ofr80236 - 1980 - Age of uranium mineralization, U-Pb isotope systematics, and ore mineralogy of the Midnite Mine, Washington","indexId":"ofr80236","publicationYear":"1980","noYear":false,"title":"Age of uranium mineralization, U-Pb isotope systematics, and ore mineralogy of the Midnite Mine, Washington"},"predicate":"SUPERSEDED_BY","object":{"id":70011757,"text":"70011757 - 1981 - U-Pb isotope systematics and age of uranium mineralization, Midnite mine, Washington.","indexId":"70011757","publicationYear":"1981","noYear":false,"title":"U-Pb isotope systematics and age of uranium mineralization, Midnite mine, Washington."},"id":1}],"lastModifiedDate":"2022-12-23T15:38:37.695623","indexId":"70011757","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1472,"text":"Economic Geology","active":true,"publicationSubtype":{"id":10}},"title":"U-Pb isotope systematics and age of uranium mineralization, Midnite mine, Washington.","docAbstract":"Uranium ores at the Midnite mine, near Spokane, Washington, occur in phyllites and calcsilicates of the Proterozoic Togo Formation, near the margins of an anomalously uraniferous, porphyritic quartz monzonite of Late Cretaceous age. The present geometry of the ore zones is tabular, with the thickest zones above depressions in the pluton-country rock contact. Analyses of high-grade ores from the mine define a 207 Pb/ 204 Pb- 235 U/ 204 Pb isochron indicating an age of mineralization of 51.0 + or - 0.5 m.y. This age coincides with a time of regional volcanic activity (Sanpoil Volcanics), shallow intrusive activity, erosion, and faulting. U-Th-Pb isotopic ages of zircons from the porphyritic quartz monzonite in the mine indicate an age of about 75 m.y., hence the present orebodies were formed about 24 m.y. after its intrusion. The 51-m.y. time of mineralization probably represents a period of mobilization and redeposition of uranium by supergene ground waters, perhaps aided by mild heating and ground preparation and preserved by a capping of newly accumulated, impermeable volcanic rocks. It seems most likely that the initial concentration of uranium occurred about 75 m.y. ago, probably from relatively mild hydrothermal fluids in the contact-metamorphic aureole of the U-rich porphyritic quartz monzonite.Pitchblende, coffinitc, pyrite, marcasite, and hisingerite are the most common minerals in the uranium-bearing veinlets, with minor sphalerite and chalcopyrite. Coffinitc with associated marcasite is paragenetically later than pitchblende, though textural and isotopic evidence suggests no large difference in the times of pitchblende and colfinite formation.The U-Pb isotope systematics of total ores and of pitchblende-coffinite and pyrite-marcasite separates show that whereas open system behavior for U and Pb is essentially negligible for large (200-500 g) ore samples, Pb migration has occurred on a scale of 1 to 10 mm (out of pitchblende and coffinite and into pyrite and marcasite). Also, long-term continuous leakage of radioactive daughters of 238 U (probably 222 Rn) has occurred on scales of from approximately 100 mu m approximately 10 cm. The isotopic composition of unsupported radiogenic Pb in pyrite-marcasite seems to depend on the mineralogical microenvironment of the grains, so that the radiogenic Pb in pyrite-marcasite intimately intermixed with pitchblende-coffinite tends to be deficient in 206 Pb, and the radiogenic Pb in pyrite-marcasite in gangue tends to have excess 206 Pb. These systematics probably reflect differences between the average distances of Pb and 222 Rn diffusion since the formation of the ores.","language":"English","publisher":"Society of Economic Geologists","doi":"10.2113/gsecongeo.76.1.89","usgsCitation":"Ludwig, K., Nash, J., and Naeser, C.W., 1981, U-Pb isotope systematics and age of uranium mineralization, Midnite mine, Washington.: Economic Geology, v. 76, no. 1, p. 89-110, https://doi.org/10.2113/gsecongeo.76.1.89.","productDescription":"22 p.","startPage":"89","endPage":"110","costCenters":[{"id":218,"text":"Denver Federal Center","active":false,"usgs":true}],"links":[{"id":221312,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Washington","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -124.79,45.54 ], [ -124.79,49.0 ], [ -116.92,49.0 ], [ -116.92,45.54 ], [ -124.79,45.54 ] ] ] } } ] }","volume":"76","issue":"1","noUsgsAuthors":false,"publicationDate":"1981-02-01","publicationStatus":"PW","scienceBaseUri":"505bb9cde4b08c986b327e05","contributors":{"authors":[{"text":"Ludwig, K.R.","contributorId":97112,"corporation":false,"usgs":true,"family":"Ludwig","given":"K.R.","email":"","affiliations":[{"id":218,"text":"Denver Federal Center","active":false,"usgs":true}],"preferred":false,"id":361895,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Nash, J. T.","contributorId":31751,"corporation":false,"usgs":true,"family":"Nash","given":"J. T.","affiliations":[],"preferred":false,"id":361894,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Naeser, C. W.","contributorId":17582,"corporation":false,"usgs":true,"family":"Naeser","given":"C.","middleInitial":"W.","affiliations":[],"preferred":false,"id":361893,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70011758,"text":"70011758 - 1981 - A stochastic fault model. 2. Time-dependent case","interactions":[],"lastModifiedDate":"2024-07-16T16:17:12.569402","indexId":"70011758","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":6453,"text":"Journal of Geophysical Research Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"A stochastic fault model. 2. Time-dependent case","docAbstract":"A random model of fault motion in an earthquake is formulated by assuming that the slip velocity is a random function of position and time truncated at zero, so that it does not have negative values. This random function is chosen to be self-affine; that is, on change of length scale, the function is multiplied by a scale factor but is otherwise unchanged statistically. A snapshot of slip velocity at a given time resembles a cluster of islands with rough topography; the final slip function is a smoother island or cluster of islands. In the Fourier transform domain, shear traction on the fault equals the slip velocity times an impedance function. The fact that this impedance function has a pole at zero frequency implies that traction and slip velocity cannot have the same spectral dependence in space and time. To describe stress fluctuations of the order of 100 bars when smoothed over a length of kilometers and of the order of kilobars at the grain size, shear traction must have a one-dimensional power spectrum is space proportional to the reciprocal wave number. Then the one-dimensional power spectrum for the slip velocity is proportional to the reciprocal wave number squared and for slip to its cube. If slip velocity has the same power law spectrum in time as in space, then the spectrum of ground acceleration will be flat (white noise) both on the fault and in the far field.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB11p10821","issn":"01480227","usgsCitation":"Andrews, D., 1981, A stochastic fault model. 2. Time-dependent case: Journal of Geophysical Research Solid Earth, v. 86, no. B11, p. 10821-10834, https://doi.org/10.1029/JB086iB11p10821.","productDescription":"14 p.","startPage":"10821","endPage":"10834","numberOfPages":"14","costCenters":[],"links":[{"id":221313,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"5059e5b2e4b0c8380cd46f13","contributors":{"authors":[{"text":"Andrews, D.J.","contributorId":7416,"corporation":false,"usgs":true,"family":"Andrews","given":"D.J.","email":"","affiliations":[],"preferred":false,"id":361896,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70011771,"text":"70011771 - 1981 - Some geologic and potential resource aspects of rutile in porphyry copper deposits","interactions":[],"lastModifiedDate":"2021-04-06T15:31:54.834899","indexId":"70011771","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1472,"text":"Economic Geology","active":true,"publicationSubtype":{"id":10}},"title":"Some geologic and potential resource aspects of rutile in porphyry copper deposits","docAbstract":"No abstract available.
","language":"English","publisher":"Society of Economic Geologists","doi":"10.2113/gsecongeo.76.8.2240","usgsCitation":"Czamanske, G., Force, E.R., and Moore, W.J., 1981, Some geologic and potential resource aspects of rutile in porphyry copper deposits: Economic Geology, v. 76, no. 8, p. 2240-2246, https://doi.org/10.2113/gsecongeo.76.8.2240.","productDescription":"7 p.","startPage":"2240","endPage":"2246","numberOfPages":"7","costCenters":[],"links":[{"id":221545,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"76","issue":"8","noUsgsAuthors":false,"publicationDate":"1981-12-01","publicationStatus":"PW","scienceBaseUri":"505b92abe4b08c986b31a050","contributors":{"authors":[{"text":"Czamanske, G.K.","contributorId":26300,"corporation":false,"usgs":true,"family":"Czamanske","given":"G.K.","email":"","affiliations":[],"preferred":false,"id":361926,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Force, E. R.","contributorId":28235,"corporation":false,"usgs":true,"family":"Force","given":"E.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":361927,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Moore, W. J.","contributorId":84334,"corporation":false,"usgs":true,"family":"Moore","given":"W.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":361928,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70182499,"text":"70182499 - 1981 - Application of spatial analysis techniques to remotely sensed images on ancillary geocoded data","interactions":[],"lastModifiedDate":"2017-03-22T15:33:03","indexId":"70182499","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Application of spatial analysis techniques to remotely sensed images on ancillary geocoded data","docAbstract":"No abstract available.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Computer mapping of natural resources and the environment, plus satellite derived data applications","language":"English","publisher":"Harvard University Laboratory of Computer Graphics and Spatial Analysis","publisherLocation":"Cambridge, MA","usgsCitation":"Greenlee, D.D., 1981, Application of spatial analysis techniques to remotely sensed images on ancillary geocoded data, chap. of Computer mapping of natural resources and the environment, plus satellite derived data applications, p. 111-120.","productDescription":"10 p. ","startPage":"111","endPage":"120","costCenters":[{"id":222,"text":"Earth Resources Observation and Science (EROS) Center","active":true,"usgs":true}],"links":[{"id":336115,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58b002dde4b01ccd54fb2823","contributors":{"authors":[{"text":"Greenlee, D. D.","contributorId":20079,"corporation":false,"usgs":true,"family":"Greenlee","given":"D.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":671279,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70182486,"text":"70182486 - 1981 - Effects of chronic exposure to arsenic trioxide on smoltification, downstream migration, and seawater adaptation of coho salmon (Oncorhynchus kisutch)","interactions":[],"lastModifiedDate":"2017-02-23T12:30:28","indexId":"70182486","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":21,"text":"Thesis"},"publicationSubtype":{"id":28,"text":"Thesis"},"title":"Effects of chronic exposure to arsenic trioxide on smoltification, downstream migration, and seawater adaptation of coho salmon (Oncorhynchus kisutch)","docAbstract":"No abstract available
","language":"English","publisher":"University of Washington","publisherLocation":"Seattle, WA","usgsCitation":"Nichols, J., 1981, Effects of chronic exposure to arsenic trioxide on smoltification, downstream migration, and seawater adaptation of coho salmon (Oncorhynchus kisutch).","costCenters":[{"id":654,"text":"Western Fisheries Research Center","active":true,"usgs":true}],"links":[{"id":336097,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"publicComments":"Master's Thesis","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58b002dde4b01ccd54fb2827","contributors":{"authors":[{"text":"Nichols, J.W.","contributorId":97290,"corporation":false,"usgs":true,"family":"Nichols","given":"J.W.","email":"","affiliations":[],"preferred":false,"id":671246,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70182485,"text":"70182485 - 1981 - Serological comparison of isolates of Aeromonas salmonicida ssp. Salmonicida","interactions":[],"lastModifiedDate":"2017-02-23T12:28:42","indexId":"70182485","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":21,"text":"Thesis"},"publicationSubtype":{"id":28,"text":"Thesis"},"title":"Serological comparison of isolates of Aeromonas salmonicida ssp. Salmonicida","docAbstract":"No abstract available
","language":"English","publisher":"University of Washington","publisherLocation":"Seattle, WA","usgsCitation":"Hahnel, G., 1981, Serological comparison of isolates of Aeromonas salmonicida ssp. Salmonicida.","costCenters":[{"id":654,"text":"Western Fisheries Research Center","active":true,"usgs":true}],"links":[{"id":336096,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"publicComments":"Master's Thesis","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58b002dde4b01ccd54fb2829","contributors":{"authors":[{"text":"Hahnel, G.B.","contributorId":79431,"corporation":false,"usgs":true,"family":"Hahnel","given":"G.B.","email":"","affiliations":[],"preferred":false,"id":671245,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70182484,"text":"70182484 - 1981 - Physiological and immunological differences among three stocks of coho salmon, Oncorhynchus kisutch","interactions":[],"lastModifiedDate":"2017-02-23T12:27:18","indexId":"70182484","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":21,"text":"Thesis"},"publicationSubtype":{"id":28,"text":"Thesis"},"title":"Physiological and immunological differences among three stocks of coho salmon, Oncorhynchus kisutch","docAbstract":"No abstract available
","language":"English","publisher":"University of Washington","publisherLocation":"Seattle, WA","usgsCitation":"D.M., G., 1981, Physiological and immunological differences among three stocks of coho salmon, Oncorhynchus kisutch.","costCenters":[{"id":654,"text":"Western Fisheries Research Center","active":true,"usgs":true}],"links":[{"id":336094,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"publicComments":"Master's Thesis","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58b002dee4b01ccd54fb282b","contributors":{"authors":[{"text":"D.M., Gould","contributorId":152299,"corporation":false,"usgs":false,"family":"D.M.","given":"Gould","email":"","affiliations":[],"preferred":false,"id":671244,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70011997,"text":"70011997 - 1981 - Sudden death at the end of the Mesozoic","interactions":[],"lastModifiedDate":"2021-12-23T15:56:25.992063","indexId":"70011997","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1427,"text":"Earth and Planetary Science Letters","active":true,"publicationSubtype":{"id":10}},"title":"Sudden death at the end of the Mesozoic","docAbstract":"A paleoecological analysis of the fossil record before and after the Cretaceous/Tertiary boundary indicates that the widespread extinctions and biological stresses around the boundary are best explained in terms of a sudden, significant, but short temperature rise. L. Alvarez and co-authors, having found an enrichment in iridium at the same boundary, postulated that it was associated with the impact of an extraterrestrial body. If this body struck the ocean, the water injected into the atmosphere may have led to a transient increase in the global surface temperature. This temperature pulse may have been primarily responsible for the effects observed in the biosphere. The pattern of extinction of higher plant species suggests that splash down occurred in the northern Pacific-Bering Sea area.
No abstract available.
","language":"English","publisher":"American Chemical Society","doi":"10.1021/es00092a012","issn":"0013936X","usgsCitation":"Davis, J., and Gloor, R., 1981, Adsorption of dissolved organics in lake water by aluminum oxide. Effect of molecular weight: Environmental Science & Technology, v. 15, no. 10, p. 1223-1229, https://doi.org/10.1021/es00092a012.","productDescription":"7 p.","startPage":"1223","endPage":"1229","costCenters":[],"links":[{"id":222236,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Switzerland","otherGeospatial":"Lake Greifensee","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n 8.691212933995217,\n 47.34413784526322\n ],\n [\n 8.69095756008025,\n 47.35278911927125\n ],\n [\n 8.686105455704649,\n 47.35849818333759\n ],\n [\n 8.681253351327996,\n 47.36334175331743\n ],\n [\n 8.6771673686942,\n 47.364552576333125\n ],\n [\n 8.6764012469514,\n 47.36628227528749\n ],\n [\n 8.671804516488635,\n 47.36783895585336\n ],\n [\n 8.662611055565293,\n 47.374584040766365\n ],\n [\n 8.653417594640871,\n 47.37302755927732\n ],\n [\n 8.651629977238429,\n 47.371298081519\n ],\n [\n 8.652140725068193,\n 47.36974150304462\n ],\n [\n 8.650353107665694,\n 47.36818487862885\n ],\n [\n 8.651374603324427,\n 47.36645524206372\n ],\n [\n 8.6508638554956,\n 47.36213090251064\n ],\n [\n 8.659035820761261,\n 47.35400018447538\n ],\n [\n 8.662355681650325,\n 47.35296213028735\n ],\n [\n 8.666441664283155,\n 47.347252467261455\n ],\n [\n 8.674358255634957,\n 47.34465696169181\n ],\n [\n 8.6771673686942,\n 47.34136913809493\n ],\n [\n 8.6771673686942,\n 47.33894640020719\n ],\n [\n 8.681253351327996,\n 47.33756192864186\n ],\n [\n 8.682274846985706,\n 47.33513901605076\n ],\n [\n 8.683807090473266,\n 47.33375444465335\n ],\n [\n 8.683807090473266,\n 47.33133135735633\n ],\n [\n 8.686105455704649,\n 47.3299466861271\n ],\n [\n 8.688148447021092,\n 47.326831043127726\n ],\n [\n 8.688148447021092,\n 47.323542109466416\n ],\n [\n 8.689425316593685,\n 47.32181100949981\n ],\n [\n 8.695043542714131,\n 47.32007985280842\n ],\n [\n 8.699895647090727,\n 47.32163789638301\n ],\n [\n 8.699129525346933,\n 47.324061428395254\n ],\n [\n 8.700917142748466,\n 47.32544625391321\n ],\n [\n 8.70474775146738,\n 47.32475384569253\n ],\n [\n 8.707812238441505,\n 47.328215796038904\n ],\n [\n 8.708067612356444,\n 47.33375444465335\n ],\n [\n 8.706279994953888,\n 47.33496594661122\n ],\n [\n 8.698618777517083,\n 47.33790804993703\n ],\n [\n 8.696065038371785,\n 47.33894640020719\n ],\n [\n 8.692234429653922,\n 47.3418882817497\n ],\n [\n 8.691212933995217,\n 47.34413784526322\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"15","issue":"10","noUsgsAuthors":false,"publicationDate":"2002-05-01","publicationStatus":"PW","scienceBaseUri":"5059e6fde4b0c8380cd47796","contributors":{"authors":[{"text":"Davis, J.A.","contributorId":71694,"corporation":false,"usgs":true,"family":"Davis","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":362518,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gloor, R.","contributorId":10929,"corporation":false,"usgs":true,"family":"Gloor","given":"R.","email":"","affiliations":[],"preferred":false,"id":362517,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70011972,"text":"70011972 - 1981 - Lu-Hf total-rock age for the Amîtsoq gneisses, West Greenland","interactions":[],"lastModifiedDate":"2015-06-10T13:20:26","indexId":"70011972","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1427,"text":"Earth and Planetary Science Letters","active":true,"publicationSubtype":{"id":10}},"title":"Lu-Hf total-rock age for the Amîtsoq gneisses, West Greenland","docAbstract":"Lu-Hf total-rock data for the Amîtsoq gneisses of West Greenland yield an age of 3.55±0.22Gy(2σ), based on the decay constant λ176Lu=1.96×10−11y−1, and an initial176Hf/177Hf ratio of 0.280482±33. The result is in good agreement with Rb-Sr total-rock and U-Pb zircon ages. In spite of severe metamorphism of the area at 2.9 Gy, zircons from two of the samples have remained on the total-rock line, and define points close to the initial Hf ratio. The initial176Hf/177Hf lies close to a chondritic Hf isotopic evolution curve from 4.55 Gy to present. This is consistent with the igneous precursors to the Amîtsoq gneisses having been derived from the mantle at or shortly before 3.6 Gy. Anomalous relationships between Hf concentration and the176Lu/177Hf ratio may suggest that trace element abundances in the Amîtsoq gneisses are partly controlled by processes related to metamorphism.
","language":"English","publisher":"Elsevier","doi":"10.1016/0012-821X(81)90093-5","issn":"0012821X","usgsCitation":"Pettingill, H., and Patchett, P., 1981, Lu-Hf total-rock age for the Amîtsoq gneisses, West Greenland: Earth and Planetary Science Letters, v. 55, no. 1, p. 150-156, https://doi.org/10.1016/0012-821X(81)90093-5.","productDescription":"7 p.","startPage":"150","endPage":"156","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":221559,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"55","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a4a81e4b0c8380cd68e0c","contributors":{"authors":[{"text":"Pettingill, H.S.","contributorId":70114,"corporation":false,"usgs":true,"family":"Pettingill","given":"H.S.","email":"","affiliations":[],"preferred":false,"id":362414,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Patchett, P. J.","contributorId":55152,"corporation":false,"usgs":true,"family":"Patchett","given":"P. J.","affiliations":[],"preferred":false,"id":362413,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70012099,"text":"70012099 - 1981 - The Galapagos Spreading Centre at 86° W: A detailed geothermal field study","interactions":[],"lastModifiedDate":"2024-07-16T16:54:00.922554","indexId":"70012099","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":6453,"text":"Journal of Geophysical Research Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"The Galapagos Spreading Centre at 86° W: A detailed geothermal field study","docAbstract":"We report here measurements of the heat flow field of the Galapagos Spreading Center on crust of age less than 1.0 m.y. The 443 measurements in an area of about 570 km2 reveal the general planform of the geothermal flux and permit the first truly areal estimate of the near-axis conductive heat flux. The intrusion process and associated hydrothermal circulation dominate the surface heat flow pattern, with circulation apparently continuing beyond the limits of our survey. The areal average of the conductive heat flux is 7.1 ± 0.8 HFU (295 ± 33 mW/m2), about one-third the heat flux predicted by plate models. The remaining heat is apparently removed by venting of hydrothermal waters at the spreading axis and through basalt outcrops and hydrothermal mounds off axis. The pattern of surface heat flux is lineated parallel to the axis and the strongly lineated topography. Sharp lateral gradients in the heat flow, greater than 10 HFU/km near escarpments and commonly expressed as high heat flow at the tops of the scarps and lower heat flow in the valleys, may indicate a local concentration of the circulation by surface fault systems and/or variable sediment thickness.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB02p00979","issn":"01480227","usgsCitation":"Green, K., Von Herzen, R.P., and Williams, D., 1981, The Galapagos Spreading Centre at 86° W: A detailed geothermal field study: Journal of Geophysical Research Solid Earth, v. 86, no. B2, p. 979-986, https://doi.org/10.1029/JB086iB02p00979.","productDescription":"8 p.","startPage":"979","endPage":"986","numberOfPages":"8","costCenters":[],"links":[{"id":221802,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"B2","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505ba740e4b08c986b32146a","contributors":{"authors":[{"text":"Green, K.E.","contributorId":88487,"corporation":false,"usgs":true,"family":"Green","given":"K.E.","email":"","affiliations":[],"preferred":false,"id":362728,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Von Herzen, R. P.","contributorId":87662,"corporation":false,"usgs":true,"family":"Von Herzen","given":"R.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":362727,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Williams, D.L.","contributorId":7681,"corporation":false,"usgs":true,"family":"Williams","given":"D.L.","email":"","affiliations":[],"preferred":false,"id":362726,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70011899,"text":"70011899 - 1981 - Preconsolidation stress of aquifer systems in areas of induced land subsidence","interactions":[],"lastModifiedDate":"2018-02-05T12:32:59","indexId":"70011899","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"Preconsolidation stress of aquifer systems in areas of induced land subsidence","docAbstract":"Aquifer systems in the Eloy-Picacho area, Arizona, the Houston-Galveston area, Texas, and the Tulare-Wasco area and Santa Clara Valley, California, appear to have been overconsolidated by an amount that ranged approximately from 1.6 to 6.2 bars (16 to 63 m of water) before man began to withdraw groundwater from them. The relation between land subsidence and water level decline in these areas, consists of two linear segments. In these areas, subsidence per unit water level decline was approximately constant until water levels had declined an amount that ranged from 16 to 63 m. When water levels declined past these values, subsidence per unit water level decline increased to larger constant values. Although slow drainage from aquitards may have contributed to this response, it is interpreted here to be caused primarily by natural overconsolidation of the compacting part of the aquifer system. The water level decline at which the ratio of subsidence to unit water level decline changed indicates approximately the amount by which the preconsolidation stress exceeded the overburden stress on the aquifer system that existed before groundwater withdrawals began.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/WR017i003p00693","usgsCitation":"Holzer, T.L., 1981, Preconsolidation stress of aquifer systems in areas of induced land subsidence: Water Resources Research, v. 17, no. 3, p. 693-704, https://doi.org/10.1029/WR017i003p00693.","productDescription":"12 p.","startPage":"693","endPage":"704","costCenters":[],"links":[{"id":221476,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arizona, California, Texas","volume":"17","issue":"3","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"505a8147e4b0c8380cd7b447","contributors":{"authors":[{"text":"Holzer, Thomas L. tholzer@usgs.gov","contributorId":2829,"corporation":false,"usgs":true,"family":"Holzer","given":"Thomas","email":"tholzer@usgs.gov","middleInitial":"L.","affiliations":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"preferred":true,"id":362244,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70011969,"text":"70011969 - 1981 - Determination of organic-matter content of Appalachian Devonian shales from gamma-ray logs","interactions":[],"lastModifiedDate":"2023-01-12T11:53:00.585526","indexId":"70011969","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":701,"text":"American Association of Petroleum Geologists Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Determination of organic-matter content of Appalachian Devonian shales from gamma-ray logs","docAbstract":"The organic-matter content of the Devonian shale of the Appalachian basin is important for assessing natural-gas resources. In most of the western part of the Appalachian basin the organic-matter content of the Devonian shale can be estimated from gamma-ray wire-line logs. Organic-matter contents estimated using these logs are compared with determinations from direct laboratory analyses of organic carbon for 74 intervals of varying thickness from 12 widely separated wells. The cumulative pool of gamma-ray logs for the Devonian shale forms a large and geographically broad data base. The approach may also be applicable to other formations.-from Author","language":"English","publisher":"American Association of Petroleum Geologists","doi":"10.1306/03B5949A-16D1-11D7-8645000102C1865D","usgsCitation":"Schmoker, J.W., 1981, Determination of organic-matter content of Appalachian Devonian shales from gamma-ray logs: American Association of Petroleum Geologists Bulletin, v. 65, no. 7, p. 1285-1298, https://doi.org/10.1306/03B5949A-16D1-11D7-8645000102C1865D.","productDescription":"14 p.","startPage":"1285","endPage":"1298","numberOfPages":"14","costCenters":[],"links":[{"id":221487,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"Appalachian Basin","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -78.67006023839807,\n 42.64702735316396\n ],\n [\n -83.03139607752705,\n 42.64702735316396\n ],\n [\n -83.03139607752705,\n 37\n ],\n [\n -78.67006023839807,\n 37\n ],\n [\n -78.67006023839807,\n 42.64702735316396\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"65","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ffbae4b0c8380cd4f370","contributors":{"authors":[{"text":"Schmoker, James W.","contributorId":52171,"corporation":false,"usgs":true,"family":"Schmoker","given":"James","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":362408,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":1014387,"text":"1014387 - 1981 - You asked for it! Plastic bag hauling of small live fish: Part II","interactions":[],"lastModifiedDate":"2012-02-02T00:04:11","indexId":"1014387","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":855,"text":"Aquaculture Magazine","active":true,"publicationSubtype":{"id":10}},"title":"You asked for it! Plastic bag hauling of small live fish: Part II","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Aquaculture Magazine","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","collaboration":"None/FF","usgsCitation":"Martin, M., 1981, You asked for it! Plastic bag hauling of small live fish: Part II: Aquaculture Magazine, v. 7, no. 2, p. 42-43.","productDescription":"p. 42-43","startPage":"42","endPage":"43","numberOfPages":"2","costCenters":[{"id":365,"text":"Leetown Science Center","active":true,"usgs":true}],"links":[{"id":129352,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"7","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49d6e4b07f02db5de624","contributors":{"authors":[{"text":"Martin, M.","contributorId":103217,"corporation":false,"usgs":true,"family":"Martin","given":"M.","affiliations":[],"preferred":false,"id":320294,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":1014386,"text":"1014386 - 1981 - You asked for it! More information on plastic bag hauling","interactions":[],"lastModifiedDate":"2012-02-02T00:04:11","indexId":"1014386","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":855,"text":"Aquaculture Magazine","active":true,"publicationSubtype":{"id":10}},"title":"You asked for it! More information on plastic bag hauling","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Aquaculture Magazine","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","collaboration":"None/FF","usgsCitation":"Martin, M., 1981, You asked for it! More information on plastic bag hauling: Aquaculture Magazine, v. 7, no. 3, p. 36-37.","productDescription":"p. 36-37","startPage":"36","endPage":"37","numberOfPages":"2","costCenters":[{"id":365,"text":"Leetown Science Center","active":true,"usgs":true}],"links":[{"id":129351,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"7","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49b6e4b07f02db5cb864","contributors":{"authors":[{"text":"Martin, M.","contributorId":103217,"corporation":false,"usgs":true,"family":"Martin","given":"M.","affiliations":[],"preferred":false,"id":320293,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ]}