{"pageNumber":"1538","pageRowStart":"38425","pageSize":"25","recordCount":40797,"records":[{"id":70120212,"text":"70120212 - 1981 - Results of a modeling workshop concerning acid precipitation","interactions":[],"lastModifiedDate":"2014-08-13T10:00:04","indexId":"70120212","displayToPublicDate":"1981-01-01T09:58:09","publicationYear":"1981","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":9,"text":"Other Report"},"title":"Results of a modeling workshop concerning acid precipitation","docAbstract":"No abstract available.","language":"English","publisher":"U.S. Fish and Wildlife Service, Western Energy and Land Use Team","publisherLocation":"Fort Collins, CO","usgsCitation":"Andrews, A., Ellison, R., Hamilton, D.B., Roelle, J.E., and Marmorek, D., 1981, Results of a modeling workshop concerning acid precipitation.","costCenters":[],"links":[{"id":292062,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53ec7bd0e4b02bf5a7674093","contributors":{"authors":[{"text":"Andrews, A.K.","contributorId":44991,"corporation":false,"usgs":true,"family":"Andrews","given":"A.K.","email":"","affiliations":[],"preferred":false,"id":497992,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ellison, R.A.","contributorId":82709,"corporation":false,"usgs":true,"family":"Ellison","given":"R.A.","email":"","affiliations":[],"preferred":false,"id":497995,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hamilton, D. B.","contributorId":79553,"corporation":false,"usgs":true,"family":"Hamilton","given":"D.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":497994,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Roelle, J. E.","contributorId":91066,"corporation":false,"usgs":true,"family":"Roelle","given":"J.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":497996,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Marmorek, D.","contributorId":66187,"corporation":false,"usgs":true,"family":"Marmorek","given":"D.","email":"","affiliations":[],"preferred":false,"id":497993,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}}
,{"id":70011998,"text":"70011998 - 1981 - Seawater sulfate reduction and sulfur isotope fractionation in basaltic systems: interaction of seawater with fayalite and magnetite at 200–350°C","interactions":[],"lastModifiedDate":"2015-06-10T14:04:41","indexId":"70011998","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Seawater sulfate reduction and sulfur isotope fractionation in basaltic systems: interaction of seawater with fayalite and magnetite at 200–350°C","docAbstract":"<p id=\"\">Sulfate reduction during seawater reaction with fayalite and with magnetite was rapid at 350&deg;C, producing equilibrium assemblages of talc-pyrite-hematite-magnetite at low water/rock ratios and talc-pyrite-hematite-anhydrite at higher water/rock ratios. At 250&deg;C, seawater reacting with fayalite produced detectable amounts of dissolved H<sub>2</sub>S, but extent of reaction of solid phases was minor after 150 days. At 200&deg;C, dissolved H<sub>2</sub>S was not detected, even after 219 days, but mass balance calculations suggest a small amount of pyrite may have formed. Reaction stoichiometry indicates that sulfate reduction requires large amounts of H<sup>+</sup>, which, in subseafloor hydrothermal systems is provided by Mg metasomatism. Seawater contains sufficient Mg to supply all the H<sup>+</sup>&nbsp;necessary for quantitative reduction of seawater sulfate.</p>\n<p id=\"\">Systematics of sulfur isotopes in the 250 and 350&deg;C experiments indicate that isotopic equilibrium is reached, and can be modeled as a Rayleigh distillation process. Isotopic composition of hydrothermally produced H<sub>2</sub>S in natural systems is strongly dependent upon the seawater/basalt ratio in the geothermal system, which controls the relative sulfide contributions from the two important sulfur sources, seawater sulfate and sulfide phases in basalt. Anhydrite precipitation during geothermal heating severely limits sulfate ingress into high temperature interaction zones. Quantitative sulfate reduction can thus be accomplished without producing strongly oxidized rocks and resultant sulfide sulfur isotope values represent a mixture of seawater and basaltic sulfur.</p>","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(81)90054-5","issn":"00167037","usgsCitation":"Shanks, W.C., Bischoff, J.L., and Rosenbauer, R.J., 1981, Seawater sulfate reduction and sulfur isotope fractionation in basaltic systems: interaction of seawater with fayalite and magnetite at 200–350°C: Geochimica et Cosmochimica Acta, v. 45, no. 11, p. 1977-1995, https://doi.org/10.1016/0016-7037(81)90054-5.","productDescription":"19 p.","startPage":"1977","endPage":"1995","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":220870,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"45","issue":"11","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8902e4b08c986b316cb3","contributors":{"authors":[{"text":"Shanks, Wayne C. III","contributorId":100527,"corporation":false,"usgs":true,"family":"Shanks","given":"Wayne","suffix":"III","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":362478,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bischoff, James L. jbischoff@usgs.gov","contributorId":1389,"corporation":false,"usgs":true,"family":"Bischoff","given":"James","email":"jbischoff@usgs.gov","middleInitial":"L.","affiliations":[],"preferred":true,"id":362476,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rosenbauer, Robert J. brosenbauer@usgs.gov","contributorId":204,"corporation":false,"usgs":true,"family":"Rosenbauer","given":"Robert","email":"brosenbauer@usgs.gov","middleInitial":"J.","affiliations":[{"id":520,"text":"Pacific Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":362477,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70011918,"text":"70011918 - 1981 - The Redskin granite: Evidence for thermogravitational diffusion in a Precambrian granite batholith","interactions":[],"lastModifiedDate":"2024-07-16T16:04:04.778321","indexId":"70011918","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 Redskin granite: Evidence for thermogravitational diffusion in a Precambrian granite batholith","docAbstract":"<p>The 1000-Ma-old composite Pikes Peak batholith consists largely of medium- to coarse-grained biotite granite but is intruded by several smaller granite plutons. Two of these, the Tarryall Mountains batholith and the Redskin Granite (Hawley, 1969; Hawley and Wobus, 1977), are here interpreted as cupolas atop the main mass of the Pikes Peak batholith.</p><p>Chemical analysis for 38 elements in rocks from the Redskin Granite, the Tarryall Mountains batholith, and the biotite granite of the Pikes Peak batholith support the contention that the compositions of the smaller plutons are unlikely to have evolved from that of the main mass of the batholith by crystal fractionation. It is believed that these compositions arose through liquid-state fractionation processes, possibly the convection-aided thermogravitational model of Shaw et al. (1976).</p><p>It is important to recognize that the chemical signature of this fractionation process can be discerned in holocrystalline rocks as well as in their glassy equivalents because the process may be instrumental in the formation of some kinds of lithophile ore deposits.</p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB11p10423","issn":"01480227","usgsCitation":"Ludington, S., 1981, The Redskin granite: Evidence for thermogravitational diffusion in a Precambrian granite batholith: Journal of Geophysical Research Solid Earth, v. 86, no. B11, p. 10423-10430, https://doi.org/10.1029/JB086iB11p10423.","productDescription":"8 p.","startPage":"10423","endPage":"10430","numberOfPages":"8","costCenters":[],"links":[{"id":220729,"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":"505ba8afe4b08c986b321da0","contributors":{"authors":[{"text":"Ludington, S.","contributorId":91987,"corporation":false,"usgs":true,"family":"Ludington","given":"S.","email":"","affiliations":[],"preferred":false,"id":362284,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70012000,"text":"70012000 - 1981 - Correlation of natural gas content to iron species in the New Albany shale group","interactions":[],"lastModifiedDate":"2023-10-02T17:15:17.117744","indexId":"70012000","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1709,"text":"Fuel","active":true,"publicationSubtype":{"id":10}},"title":"Correlation of natural gas content to iron species in the New Albany shale group","docAbstract":"<p><span>Mössbauer parameters were obtained for four Illinois Basin shales and their corresponding &lt; 2μm clay fractions from wells drilled through the New Albany Shale Group in Henderson, Tazewell, and Effingham counties in Illinois and Christian County in Kentucky. Off-gas analysis indicated that the Illinois cores were in an area of low gas potential, while the Kentucky core was in an area of moderate-to-good potential. Iron-rich dolomite (ankerite) was found in the Kentucky core but not in the Illinois cores. In the Kentucky core, gas content could be correlated with the ankerite in the bulk sample, the Mössbauer M (2) species in the clay fraction, and a ferrous iron species in the clay fraction. The location of the greatest concentration of natural gas in the Kentucky core could be predicted by following the changes in percentage concentration of these iron species when plotted against the depth of burial of the core sample.</span></p>","language":"English","publisher":"Elsevier","doi":"10.1016/0016-2361(81)90228-3","issn":"00162361","usgsCitation":"Shiley, R., Cluff, R., Dickerson, D.R., Hinckley, C., Smith, G.V., Twardowska, H., and Saporoschenko, M., 1981, Correlation of natural gas content to iron species in the New Albany shale group: Fuel, v. 60, no. 8, p. 732-738, https://doi.org/10.1016/0016-2361(81)90228-3.","productDescription":"7 p.","startPage":"732","endPage":"738","costCenters":[],"links":[{"id":220944,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Illinois, Kentucky","county":"Christian County, Effingham County, Henderson County, Tazewell County","otherGeospatial":"New Albany Shale Group","geographicExtents":"{\"type\":\"FeatureCollection\",\"features\":[{\"type\":\"Feature\",\"id\":617,\"properties\":{\"name\":\"Effingham\",\"state\":\"IL\"},\"geometry\":{\"type\":\"Polygon\",\"coordinates\":[[[-88.4704,39.2141],[-88.4698,39.1715],[-88.3606,39.1706],[-88.3613,39.0904],[-88.3621,39.0011],[-88.3623,38.9109],[-88.4705,38.9132],[-88.5805,38.9141],[-88.6301,38.9153],[-88.6597,38.9151],[-88.6946,38.9139],[-88.807,38.911],[-88.8074,38.9989],[-88.8077,39.0864],[-88.8075,39.1725],[-88.8077,39.2156],[-88.6954,39.2158],[-88.6337,39.2159],[-88.5844,39.2155],[-88.5173,39.2141],[-88.4704,39.2141]]]}},{\"type\":\"Feature\",\"id\":628,\"properties\":{\"name\":\"Henderson\",\"state\":\"IL\"},\"geometry\":{\"type\":\"Polygon\",\"coordinates\":[[[-90.9489,41.0718],[-90.9006,41.0703],[-90.878,41.0706],[-90.8756,41.0706],[-90.8683,41.0707],[-90.8311,41.0706],[-90.8262,41.0707],[-90.7866,41.0697],[-90.7868,40.9812],[-90.787,40.8946],[-90.7873,40.807],[-90.7875,40.7181],[-90.789,40.636],[-90.9041,40.6375],[-90.9405,40.6371],[-90.9611,40.6364],[-90.9647,40.6363],[-90.9974,40.635],[-91.0216,40.6348],[-91.1356,40.6374],[-91.1834,40.639],[-91.177,40.6419],[-91.1673,40.6465],[-91.1595,40.6503],[-91.1535,40.654],[-91.1425,40.6585],[-91.1373,40.661],[-91.1319,40.6642],[-91.1277,40.6668],[-91.1233,40.6704],[-91.1196,40.6744],[-91.1171,40.6785],[-91.1148,40.6826],[-91.113,40.6883],[-91.1122,40.6956],[-91.1115,40.7012],[-91.1111,40.7085],[-91.1122,40.7133],[-91.1138,40.7193],[-91.1142,40.726],[-91.1135,40.7296],[-91.1123,40.7343],[-91.1107,40.7391],[-91.1095,40.7435],[-91.1074,40.7468],[-91.1054,40.7499],[-91.1018,40.754],[-91.0995,40.7576],[-91.0966,40.7615],[-91.0947,40.7656],[-91.0926,40.7714],[-91.0913,40.7764],[-91.0897,40.7804],[-91.0892,40.7886],[-91.09,40.795],[-91.0928,40.8041],[-91.0946,40.8094],[-91.0942,40.8137],[-91.0922,40.8186],[-91.0894,40.8235],[-91.0841,40.8266],[-91.0802,40.8303],[-91.0778,40.8333],[-91.0757,40.8355],[-91.0715,40.8387],[-91.0672,40.8408],[-91.0637,40.8434],[-91.0585,40.847],[-91.0547,40.851],[-91.0502,40.8568],[-91.046,40.864],[-91.0431,40.8694],[-91.0359,40.8759],[-91.0282,40.8833],[-91.0218,40.8881],[-91.0162,40.8939],[-91.0073,40.9023],[-91.0043,40.9049],[-91.0013,40.9067],[-90.9983,40.9081],[-90.9943,40.9093],[-90.9898,40.9105],[-90.9856,40.9124],[-90.9813,40.9149],[-90.9808,40.9152],[-90.976,40.9175],[-90.9718,40.9193],[-90.9674,40.9222],[-90.9645,40.925],[-90.9611,40.9322],[-90.9582,40.9403],[-90.9558,40.9485],[-90.9541,40.9535],[-90.9531,40.9567],[-90.9525,40.9599],[-90.9526,40.9631],[-90.9539,40.9667],[-90.9558,40.9699],[-90.9565,40.9744],[-90.9572,40.978],[-90.9566,40.9817],[-90.9549,40.9844],[-90.9538,40.9865],[-90.9519,40.9903],[-90.9502,40.9958],[-90.9485,41.0031],[-90.9474,41.0085],[-90.9467,41.0145],[-90.9459,41.0213],[-90.9455,41.0304],[-90.9452,41.0404],[-90.9449,41.0481],[-90.9459,41.0549],[-90.948,41.0622],[-90.9485,41.0677],[-90.9489,41.0718]]]}},{\"type\":\"Feature\",\"id\":682,\"properties\":{\"name\":\"Tazewell\",\"state\":\"IL\"},\"geometry\":{\"type\":\"Polygon\",\"coordinates\":[[[-89.5504,40.7477],[-89.5025,40.7473],[-89.3897,40.7481],[-89.3308,40.749],[-89.3309,40.7172],[-89.3281,40.6152],[-89.2694,40.616],[-89.2682,40.5947],[-89.2683,40.572],[-89.2662,40.4854],[-89.2647,40.3978],[-89.2643,40.3266],[-89.6038,40.3209],[-89.7154,40.319],[-89.7169,40.4355],[-89.9235,40.4364],[-89.9187,40.4382],[-89.9115,40.4423],[-89.9054,40.4487],[-89.9037,40.4532],[-89.9019,40.4591],[-89.8977,40.4636],[-89.8875,40.475],[-89.8863,40.4786],[-89.8851,40.4864],[-89.8804,40.5059],[-89.878,40.5091],[-89.875,40.5113],[-89.8714,40.5132],[-89.8587,40.5191],[-89.8333,40.5296],[-89.8255,40.5341],[-89.8195,40.5373],[-89.8025,40.5437],[-89.7887,40.5469],[-89.7711,40.5524],[-89.7645,40.552],[-89.756,40.5506],[-89.7415,40.5507],[-89.7342,40.5525],[-89.7288,40.5543],[-89.7191,40.5552],[-89.7094,40.5575],[-89.7004,40.5612],[-89.6949,40.5607],[-89.6895,40.5575],[-89.6828,40.5517],[-89.6683,40.5598],[-89.6604,40.5676],[-89.6562,40.5726],[-89.6544,40.578],[-89.6562,40.583],[-89.6593,40.5875],[-89.6593,40.593],[-89.6575,40.5984],[-89.6533,40.6039],[-89.646,40.6125],[-89.64,40.6188],[-89.6364,40.6234],[-89.6291,40.6288],[-89.6236,40.6352],[-89.6146,40.6452],[-89.614,40.652],[-89.6152,40.6579],[-89.6134,40.6633],[-89.6007,40.676],[-89.5843,40.6865],[-89.5692,40.6951],[-89.5571,40.701],[-89.554,40.7028],[-89.5504,40.7096],[-89.545,40.7196],[-89.5462,40.7278],[-89.5474,40.7328],[-89.548,40.74],[-89.5504,40.7477]]]}},{\"type\":\"Feature\",\"id\":1014,\"properties\":{\"name\":\"Christian\",\"state\":\"KY\"},\"geometry\":{\"type\":\"Polygon\",\"coordinates\":[[[-87.3334,37.1571],[-87.3345,37.1521],[-87.3344,37.148],[-87.3319,37.1408],[-87.3307,37.1395],[-87.3288,37.135],[-87.324,37.1246],[-87.3216,37.1224],[-87.3168,37.1138],[-87.3173,37.112],[-87.305,37.1063],[-87.3033,37.1063],[-87.3005,37.1082],[-87.3023,37.1118],[-87.3006,37.1132],[-87.2954,37.1128],[-87.2907,37.1101],[-87.2843,37.108],[-87.2854,37.1034],[-87.284,37.0953],[-87.285,37.0889],[-87.2855,37.0866],[-87.2849,37.0844],[-87.2825,37.0817],[-87.2819,37.0794],[-87.2807,37.0772],[-87.2725,37.0723],[-87.2679,37.0742],[-87.2646,37.0779],[-87.2605,37.0775],[-87.2592,37.0725],[-87.2714,37.0002],[-87.3358,36.6425],[-87.4349,36.6417],[-87.4367,36.6417],[-87.4847,36.6409],[-87.6424,36.6385],[-87.6942,36.6377],[-87.6829,36.7032],[-87.675,36.7501],[-87.6719,36.8785],[-87.66,36.9662],[-87.7296,36.9999],[-87.7337,37.0021],[-87.7106,37.0216],[-87.6809,37.1491],[-87.6688,37.1497],[-87.6496,37.1469],[-87.6222,37.1352],[-87.5238,37.106],[-87.5203,37.1052],[-87.5146,37.1071],[-87.5112,37.1099],[-87.5118,37.1126],[-87.5062,37.1163],[-87.4993,37.1178],[-87.4959,37.1214],[-87.492,37.1251],[-87.4851,37.1266],[-87.3744,37.1338],[-87.3705,37.1366],[-87.3613,37.1413],[-87.3597,37.144],[-87.3598,37.1499],[-87.36,37.1567],[-87.3514,37.1591],[-87.3404,37.1575],[-87.3363,37.1548],[-87.3334,37.1571]]]}}]}","volume":"60","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fc3de4b0c8380cd4e1bf","contributors":{"authors":[{"text":"Shiley, R.H.","contributorId":44282,"corporation":false,"usgs":true,"family":"Shiley","given":"R.H.","email":"","affiliations":[],"preferred":false,"id":362482,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cluff, R.M.","contributorId":53948,"corporation":false,"usgs":true,"family":"Cluff","given":"R.M.","email":"","affiliations":[],"preferred":false,"id":362484,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dickerson, D. R.","contributorId":66837,"corporation":false,"usgs":true,"family":"Dickerson","given":"D.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":362485,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hinckley, C.C.","contributorId":50656,"corporation":false,"usgs":true,"family":"Hinckley","given":"C.C.","email":"","affiliations":[],"preferred":false,"id":362483,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Smith, Gerard V.","contributorId":93629,"corporation":false,"usgs":true,"family":"Smith","given":"Gerard","email":"","middleInitial":"V.","affiliations":[],"preferred":false,"id":362486,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Twardowska, H.","contributorId":98038,"corporation":false,"usgs":true,"family":"Twardowska","given":"H.","email":"","affiliations":[],"preferred":false,"id":362487,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Saporoschenko, Mykola","contributorId":31905,"corporation":false,"usgs":true,"family":"Saporoschenko","given":"Mykola","email":"","affiliations":[],"preferred":false,"id":362481,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}}
,{"id":70012048,"text":"70012048 - 1981 - Flow through fractures","interactions":[],"lastModifiedDate":"2018-02-05T12:34:17","indexId":"70012048","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":"Flow through fractures","docAbstract":"<p><span>Flow through fractures is often idealized as flow between two parallel plates (plane Poiseuille flow). The opening or aperture between parallel plates is unambiguous and its relation to flowrate is well known. However, fractures in rock have uneven walls and a variable aperture. A model for flow in a fracture is proposed wherein the fracture is represented by a set of parallel plate openings with different apertures. The model leads to a modified Poiseuille equation for flow which includes an aperture frequency distribution for the fracture. Any arbitrary aperture distribution can be used; in order to simplify computation and demonstrate the properties of the model a log normal form of distribution is assumed. Even when an analytical form of the distribution is assumed, two parameters, rather than a single value representing ‘aperture size’ are required to determine flowrate. Models of aperture change for a fracture undergoing compression (fracture walls deforming) and extension (fracture walls separating) are developed which constrain the additional parameter and allow calculation of flowrate as a function of mean aperture. The theoretical relationships developed between mean aperture and flowrate can be used to interpret published laboratory data for single fractures.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/WR017i001p00191","usgsCitation":"Neuzil, C., and Tracy, J.V., 1981, Flow through fractures: Water Resources Research, v. 17, no. 1, p. 191-199, https://doi.org/10.1029/WR017i001p00191.","productDescription":"9 p.","startPage":"191","endPage":"199","costCenters":[],"links":[{"id":222694,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"17","issue":"1","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"505a1255e4b0c8380cd5427d","contributors":{"authors":[{"text":"Neuzil, C. E. 0000-0003-2022-4055","orcid":"https://orcid.org/0000-0003-2022-4055","contributorId":81078,"corporation":false,"usgs":true,"family":"Neuzil","given":"C. E.","affiliations":[],"preferred":false,"id":362611,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Tracy, James V.","contributorId":52585,"corporation":false,"usgs":true,"family":"Tracy","given":"James","email":"","middleInitial":"V.","affiliations":[],"preferred":false,"id":362610,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70012004,"text":"70012004 - 1981 - Matrix modification with silver for the electrothermal atomization of arsenic and selenium","interactions":[],"lastModifiedDate":"2023-03-07T16:58:51.554955","indexId":"70012004","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":760,"text":"Analytica Chimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Matrix modification with silver for the electrothermal atomization of arsenic and selenium","docAbstract":"<p><span>Silver as a matrix modifier is shown to improve the carbon-rod atomization of both arsenic and selenium for atomic absorption spectrometry. Compared to nickel, the efficiency of silver is greater for arsenic and about the same for selenium. Silver fulfils two functions in its reaction, namely stabilization during the ashing stage and enhancement of absorbance in the final atomization.</span></p>","language":"English","publisher":"Elsevier","doi":"10.1016/S0003-2670(01)84103-9","usgsCitation":"Sanzolone, R.F., and Chao, T.T., 1981, Matrix modification with silver for the electrothermal atomization of arsenic and selenium: Analytica Chimica Acta, v. 128, no. C, p. 225-227, https://doi.org/10.1016/S0003-2670(01)84103-9.","productDescription":"3 p.","startPage":"225","endPage":"227","numberOfPages":"3","costCenters":[],"links":[{"id":220948,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"128","issue":"C","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a528ee4b0c8380cd6c4dc","contributors":{"authors":[{"text":"Sanzolone, R. F.","contributorId":64199,"corporation":false,"usgs":true,"family":"Sanzolone","given":"R.","middleInitial":"F.","affiliations":[],"preferred":false,"id":362497,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chao, T. T.","contributorId":31900,"corporation":false,"usgs":true,"family":"Chao","given":"T.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":362496,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70011944,"text":"70011944 - 1981 - Cretaceous Arctic silicoflagellates","interactions":[],"lastModifiedDate":"2012-03-12T17:18:29","indexId":"70011944","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1742,"text":"Geo-Marine Letters","active":true,"publicationSubtype":{"id":10}},"title":"Cretaceous Arctic silicoflagellates","docAbstract":"Cretaceous silicoflagellate assemblages from Arctic Ocean USGS Core 437 show Vallacerta siderea the most abundant species; most species of Lyramula disappear halfway up the core; only L. burchardae, n. sp., persists into the upper sections. These occurrences are untypical of the few documented Cretaceous assemblages from other areas. A Campanian or Maestrichtian age is suggested by correlation, but the uniquely high abundance of V. siderea and lack of Corbisema suggests that a difference in both age and general environment could be involved. If Core 437 is latest Maestrichtian, then the evidence from this core would constrain the timing of the ocean-freshening model for the Cretaceous-Tertiary boundary extinctions. ?? 1981 A.M. Dowden, Inc.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geo-Marine Letters","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Springer-Verlag","doi":"10.1007/BF02463303","issn":"02760460","usgsCitation":"Bukry, D., 1981, Cretaceous Arctic silicoflagellates: Geo-Marine Letters, v. 1, no. 1, p. 57-63, https://doi.org/10.1007/BF02463303.","startPage":"57","endPage":"63","numberOfPages":"7","costCenters":[],"links":[{"id":221143,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205092,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF02463303"}],"volume":"1","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fca5e4b0c8380cd4e36d","contributors":{"authors":[{"text":"Bukry, D.","contributorId":15338,"corporation":false,"usgs":true,"family":"Bukry","given":"D.","affiliations":[],"preferred":false,"id":362363,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70011946,"text":"70011946 - 1981 - 13C 12C exchange between calcite and graphite: A possible thermometer in Grenville marbles","interactions":[],"lastModifiedDate":"2024-03-14T16:02:34.074509","indexId":"70011946","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"displayTitle":"<sup>13</sup>C <sup>12</sup>C exchange between calcite and graphite: A possible thermometer in Grenville marbles","title":"13C 12C exchange between calcite and graphite: A possible thermometer in Grenville marbles","docAbstract":"<p>The fractionation of<span>&nbsp;</span><sup>13</sup>C between calcite and graphite, Δ(Cc-Gr). is consistently small (2.6–4.8 permil) in 34 assemblages from upper amphibolite- and granulite-facies marbles of the Grenville Province. In 25 samples from the Adirondack Mountains, New York, it decreases regularly with increasing metamorphic temperature. The fractionations are independent of absolute δ<sup>13</sup>C values of calcite (−2.9 to +5.0). For<span>&nbsp;</span><i>T</i><span>&nbsp;</span>= 600–800°<i>C</i>, the Adirondack data are described by<span>&nbsp;</span><i>Δ</i>(<i>Cc</i>-<i>Gr</i>) = −0.00748<i>T</i><span>&nbsp;</span>(°<i>C</i>) + 8.68. This good correlation between Δ and<span>&nbsp;</span><i>T</i><span>&nbsp;</span>suggests that carbon isotope equilibrium was attained in these high-grade marbles and that the theoretical calculations of this fractionation by Bottinga are approximately 2 permil too large in this temperature range. Because of the relatively high temperature sensitivity suggested by these results and by Bottinga's calculations, and the pressure independence of isotope fractionation, Δ(Cc-Gr) may provide a very good thermometer for high-grade marbles.</p><p>Comparison of this field calibration for Δ(Cc-Gr) vs temperature with results from other terranes supports the utility of Δ(Cc-Gr) for geothermometry and suggests that graphite is much more sluggish to exchange than calcite, that exchange between calcite and graphite occurs at temperatures as low as 300°C, and that equilibrium may normally be attained only when peak metamorphic temperatures are greater than 500–600°C.</p><p>Because<span>&nbsp;</span><sup>13</sup>C exchange is an unavoidable metamorphic process at temperatures above 300°C, high values of δ<sup>13</sup>C(Gr) in moderate- to high-grade carbonate-bearing rocks do not provide a sufficient criterion to infer an abiogenic origin for the graphite.</p>","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(81)90249-0","issn":"00167037","usgsCitation":"Valley, J., and O’Neil, J.R., 1981, 13C 12C exchange between calcite and graphite: A possible thermometer in Grenville marbles: Geochimica et Cosmochimica Acta, v. 45, no. 3, p. 411-419, https://doi.org/10.1016/0016-7037(81)90249-0.","productDescription":"9 p.","startPage":"411","endPage":"419","numberOfPages":"9","costCenters":[],"links":[{"id":480581,"rank":2,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"http://hdl.handle.net/2027.42/24452>","text":"External Repository"},{"id":221204,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"45","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e224e4b0c8380cd459ba","contributors":{"authors":[{"text":"Valley, J.W.","contributorId":28741,"corporation":false,"usgs":true,"family":"Valley","given":"J.W.","email":"","affiliations":[],"preferred":false,"id":362367,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"O’Neil, J. R.","contributorId":69633,"corporation":false,"usgs":true,"family":"O’Neil","given":"J.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":362368,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70011952,"text":"70011952 - 1981 - Interpretation of changes in water level accompanying fault creep and implications for earthquake prediction","interactions":[],"lastModifiedDate":"2024-07-16T15:54:28.337138","indexId":"70011952","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":"Interpretation of changes in water level accompanying fault creep and implications for earthquake prediction","docAbstract":"<p><span>Quantitative calculations for the effect of a fault creep event on observations of changes in water level in wells provide an approach to the tectonic interpretation of these phenomena. For the pore pressure field associated with an idealized creep event having an exponential displacement versus time curve, an analytic expression has been obtained in terms of exponential-integral functions. The pore pressure versus time curves for observation points near the fault are pulselike; a sharp pressure increase (or decrease, depending on the direction of propagation) is followed by more gradual decay to the normal level after the creep event. The time function of the water level change may be obtained by applying the filter—derived by A. G. Johnson and others to determine the influence of atmospheric pressure on water level—to the analytic pore pressure versus time curves. The resulting water level curves show a fairly rapid increase (or decrease) and then a very gradual return to normal. The results of this analytic model do not reproduce the steplike changes in water level observed by Johnson and others. If the procedure used to obtain the water level from the pore pressure is correct, these results suggest that steplike changes in water level are not produced by smoothly propagating creep events but by creep events that propagate discontinously, by changes in the bulk properties of the region around the well, or by some other mechanism. In addition, simplistic calculations show that significant pressure field variations and water level changes near the surface may be expected to accompany a propagating creep event on a buried fault. Water level changes of as much as several meters may be expected at the surface for a creep event having a dislocation amplitude of l m on a semi-infinite dislocation surface extending downward from a depth of 10 km and propagating horizontally at a rate of 10 km/day. The maximum near-surface effect should be observed at a horizontal distance from the fault about equal to the depth of the top of the dislocation surface. These results are consistent with the observations made in China of large water level changes preceding large earthquakes, if some sort of aseismic creep event at depth precedes these earthquakes.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB10p09259","issn":"01480227","usgsCitation":"Wesson, R.L., 1981, Interpretation of changes in water level accompanying fault creep and implications for earthquake prediction: Journal of Geophysical Research Solid Earth, v. 86, no. B10, p. 9259-9267, https://doi.org/10.1029/JB086iB10p09259.","productDescription":"9 p.","startPage":"9259","endPage":"9267","numberOfPages":"9","costCenters":[],"links":[{"id":221266,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"B10","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a3d6ae4b0c8380cd6355f","contributors":{"authors":[{"text":"Wesson, R. L.","contributorId":51752,"corporation":false,"usgs":true,"family":"Wesson","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":362379,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70011933,"text":"70011933 - 1981 - Chrysophyte cysts as potential environmental indicators","interactions":[],"lastModifiedDate":"2024-01-04T01:50:16.705788","indexId":"70011933","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Chrysophyte cysts as potential environmental indicators","docAbstract":"<div id=\"15238342\" class=\"article-section-wrapper js-article-section js-content-section  \" data-section-parent-id=\"0\"><p>Many Chrysophyte algae produce morphologically distinctive, siliceous, microscopic cysts during a resting stage of their life cycles; these cysts are often preserved in sediments. Scanning electron microscopy and Nomarski optics permit much more detailed observation of these cysts than was heretofore possible. We have used an ecologic and biogeographic approach to study the distribution of cyst forms in sediments and have established that many cyst types are found only in specific habitats, such as montane lakes, wet meadows, ephemeral ponds, and<span>&nbsp;</span><i>Sphagnum</i><span>&nbsp;</span>bogs. In the samples we have studied, cysts seem to be most common in fluctuating fresh-water habitats of low to moderate pH and some winter freezing. Numerous taxonomic problems have yet to be resolved. We believe that chrysophyte cysts have the potential to become a useful tool for both modern environmental assessments and paleoecological studies of Cenozoic fresh-water lacustrine deposits.</p></div>","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1981)92<839:CCAPEI>2.0.CO;2","usgsCitation":"Adam, D., and Mahood, A., 1981, Chrysophyte cysts as potential environmental indicators: Geological Society of America Bulletin, v. 92, no. 11 pt I, p. 839-844, https://doi.org/10.1130/0016-7606(1981)92<839:CCAPEI>2.0.CO;2.","productDescription":"6 p.","startPage":"839","endPage":"844","numberOfPages":"6","costCenters":[],"links":[{"id":221006,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"92","issue":"11 pt I","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f5fbe4b0c8380cd4c527","contributors":{"authors":[{"text":"Adam, D.P.","contributorId":14815,"corporation":false,"usgs":true,"family":"Adam","given":"D.P.","email":"","affiliations":[],"preferred":false,"id":362329,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mahood, A.D.","contributorId":55960,"corporation":false,"usgs":true,"family":"Mahood","given":"A.D.","email":"","affiliations":[],"preferred":false,"id":362330,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70011739,"text":"70011739 - 1981 - Thermal modeling of cometary nuclei","interactions":[],"lastModifiedDate":"2024-02-20T13:21:04.145178","indexId":"70011739","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1963,"text":"Icarus","active":true,"publicationSubtype":{"id":10}},"title":"Thermal modeling of cometary nuclei","docAbstract":"<div id=\"preview-section-abstract\"><div id=\"abstracts\" class=\"Abstracts u-font-serif text-s\"><div id=\"aep-abstract-id6\" class=\"abstract author\"><div id=\"aep-abstract-sec-id7\"><p>A new model of the sublimation of volatile ices from a cometary nucleus has been developed which includes the effects of diurnal heating and cooling, rotation period and pole orientation, and thermal properties of the ice and subsurface layers. The model also includes the contribution from coma opacity, scattering, and thermal emission, where the properties of the coma are derived from the integrated rate of volatile production by the nucleus. The model is applied to the specific case of the 1986 apparition of Halley's comet. It is found that the generation of a cometary dust coma actually increases the total energy reaching the Halley nucleus. This results because of the significantly greater geometrical cross section of the coma as compared with the bare nucleus, and because the coma provides an essentially isotropic source of multiply scattered sunlight and thermal emission over the entire nucleus surface. For Halley, the calculated coma opacity is approximately 0.2 at 1 AU from the Sun, and 1.2 at perihelion (0.587 AU). At 1 AU this has little effect on dayside temperatures (maximum ≈200°K) but raises nightside temperatures (minimum ≈150°K) by about 40°K. At perihelion the higher opacity results in a nearly isothermal nucleus with only small diurnal and latitudinal temperature variations. The general surface temperature is 205°K with a maximum of 209°K at local noon on the equator. Some possible consequences of the results with respect to the generation of nongravitational forces, observed volatile production rates for comets, and cometary lifetimes against sublimation are discussed.</p></div></div></div></div><div id=\"preview-section-introduction\"><br></div><div id=\"preview-section-snippets\"><br></div><div id=\"preview-section-references\"><br></div>","language":"English","publisher":"Elsevier","doi":"10.1016/0019-1035(81)90177-9","issn":"00191035","usgsCitation":"Weissman, P., and Kieffer, H.H., 1981, Thermal modeling of cometary nuclei: Icarus, v. 47, no. 3, p. 302-311, https://doi.org/10.1016/0019-1035(81)90177-9.","productDescription":"10 p.","startPage":"302","endPage":"311","numberOfPages":"10","costCenters":[],"links":[{"id":220788,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"47","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb24be4b08c986b3256e0","contributors":{"authors":[{"text":"Weissman, P.R.","contributorId":7838,"corporation":false,"usgs":true,"family":"Weissman","given":"P.R.","email":"","affiliations":[],"preferred":false,"id":361848,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kieffer, H. H.","contributorId":40725,"corporation":false,"usgs":false,"family":"Kieffer","given":"H.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":361849,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70011958,"text":"70011958 - 1981 - Storm-built sand ridges on the Maryland inner shelf: a preliminary report","interactions":[],"lastModifiedDate":"2012-03-12T17:18:35","indexId":"70011958","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1742,"text":"Geo-Marine Letters","active":true,"publicationSubtype":{"id":10}},"title":"Storm-built sand ridges on the Maryland inner shelf: a preliminary report","docAbstract":"Several aspects of the Maryland ridge field are pertinent to the problem of ridge genesis in response to Holocene sea-level rise. There is a systematic morphologic change from shoreface ridges through nearshore ridges to offshore ridges, which reflects the changing hydraulic regime. Grain size is 90?? out of phase with topography, so that the coarsest sand lies between the axis of each trough and the adjacent seaward ridge crest, while the finest sand lies between each ridge crest and the axis of the adjacent seaward trough. Finally, analysis over a 43-year period on an outer ridge reveals a systematic pattern of landward flank erosion, seaward flank deposition, and seaward crest migration. These relationships support a model which explains the ridges as consequences of the up-current shift of maximum bottom shear stress with respect to the crests of initial bottom irregularities. The oblique orientation of the ridges with respect to the beach may be at least partly due to the more rapid migration rate of the ridges' inshore ends. ?? 1981 A.M. Dowden, Inc.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geo-Marine Letters","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Springer-Verlag","doi":"10.1007/BF02463299","issn":"02760460","usgsCitation":"Swift, D., and Field, M., 1981, Storm-built sand ridges on the Maryland inner shelf: a preliminary report: Geo-Marine Letters, v. 1, no. 1, p. 33-37, https://doi.org/10.1007/BF02463299.","startPage":"33","endPage":"37","numberOfPages":"5","costCenters":[],"links":[{"id":205111,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF02463299"},{"id":221331,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"1","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b987be4b08c986b31c058","contributors":{"authors":[{"text":"Swift, D.J.P.","contributorId":18505,"corporation":false,"usgs":true,"family":"Swift","given":"D.J.P.","email":"","affiliations":[],"preferred":false,"id":362387,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Field, M.E.","contributorId":27052,"corporation":false,"usgs":true,"family":"Field","given":"M.E.","affiliations":[],"preferred":false,"id":362388,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70011984,"text":"70011984 - 1981 - Computer-assisted photogrammetric mapping systems for geologic studies-A progress report","interactions":[],"lastModifiedDate":"2013-03-20T19:48:14","indexId":"70011984","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3050,"text":"Photogrammetria","active":true,"publicationSubtype":{"id":10}},"title":"Computer-assisted photogrammetric mapping systems for geologic studies-A progress report","docAbstract":"Photogrammetry has played an important role in geologic mapping for many years; however, only recently have attempts been made to automate mapping functions for geology. Computer-assisted photogrammetric mapping systems for geologic studies have been developed and are currently in use in offices of the Geological Survey of Greenland at Copenhagen, Denmark, and the U.S. Geological Survey at Denver, Colorado. Though differing somewhat, the systems are similar in that they integrate Kern PG-2 photogrammetric plotting instruments and small desk-top computers that are programmed to perform special geologic functions and operate flat-bed plotters by means of specially designed hardware and software. A z-drive capability, in which stepping motors control the z-motions of the PG-2 plotters, is an integral part of both systems. This feature enables the computer to automatically position the floating mark on computer-calculated, previously defined geologic planes, such as contacts or the base of coal beds, throughout the stereoscopic model in order to improve the mapping capabilities of the instrument and to aid in correlation and tracing of geologic units. The common goal is to enhance the capabilities of the PG-2 plotter and provide a means by which geologists can make conventional geologic maps more efficiently and explore ways to apply computer technology to geologic studies. ?? 1981.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Photogrammetria","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/0031-8663(81)90012-0","issn":"00318663","usgsCitation":"Pillmore, C.L., Dueholm, K., Jepsen, H., and Schuch, C., 1981, Computer-assisted photogrammetric mapping systems for geologic studies-A progress report: Photogrammetria, v. 36, no. 5, p. 159-171, https://doi.org/10.1016/0031-8663(81)90012-0.","startPage":"159","endPage":"171","numberOfPages":"13","costCenters":[],"links":[{"id":221783,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":269812,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0031-8663(81)90012-0"}],"volume":"36","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f96fe4b0c8380cd4d5e6","contributors":{"authors":[{"text":"Pillmore, C. L.","contributorId":46093,"corporation":false,"usgs":true,"family":"Pillmore","given":"C.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":362441,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dueholm, K.S.","contributorId":98338,"corporation":false,"usgs":true,"family":"Dueholm","given":"K.S.","affiliations":[],"preferred":false,"id":362443,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Jepsen, H.S.","contributorId":105856,"corporation":false,"usgs":true,"family":"Jepsen","given":"H.S.","email":"","affiliations":[],"preferred":false,"id":362444,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Schuch, C.H.","contributorId":96419,"corporation":false,"usgs":true,"family":"Schuch","given":"C.H.","email":"","affiliations":[],"preferred":false,"id":362442,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70011957,"text":"70011957 - 1981 - Systems for measuring thickness of temperate and polar ice from the ground or from the air.","interactions":[],"lastModifiedDate":"2024-05-07T00:16:51.493199","indexId":"70011957","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2328,"text":"Journal of Glaciology","active":true,"publicationSubtype":{"id":10}},"title":"Systems for measuring thickness of temperate and polar ice from the ground or from the air.","docAbstract":"<div class=\"abstract-content\"><div class=\"abstract\" data-abstract-type=\"normal\"><p>Equipment has been designed and tested for ground-based and airborne sounding of temperate glaciers. The transmitter is a free-running pulse generator that uses avalanche-mode transistor breakdown to create high-voltage pulses. The transmit and receive antennas are resistively loaded dipoles; for the airborne system, a twin-lead transmit element and a three-layer coaxial receive element are used on the inboard end of the respective antennas. The sounders are broadband systems; oscilloscopes are used for receivers. The oscilloscope trace is recorded photographically in the ground-based systems. A sampling oscilloscope is used in the airborne system—the sampling process strobes the waveform to audio frequencies so that it can be recorded on magnetic tape. Echoes have been obtained from ice depths of 550 m using the airborne system and about 1 000 m using the ground-based system.</p></div></div>","language":"English","publisher":"Cambridge University Press","doi":"10.3189/S0022143000011485","issn":"00221430","usgsCitation":"Watts, R., and Wright, D., 1981, Systems for measuring thickness of temperate and polar ice from the ground or from the air.: Journal of Glaciology, v. 27, no. 97, p. 459-469, https://doi.org/10.3189/S0022143000011485.","productDescription":"11 p.","startPage":"459","endPage":"469","numberOfPages":"11","costCenters":[],"links":[{"id":486978,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.3189/s0022143000011485","text":"Publisher Index Page"},{"id":221330,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"27","issue":"97","noUsgsAuthors":false,"publicationDate":"2017-01-20","publicationStatus":"PW","scienceBaseUri":"505ba377e4b08c986b31fcf4","contributors":{"authors":[{"text":"Watts, R.D.","contributorId":94666,"corporation":false,"usgs":true,"family":"Watts","given":"R.D.","email":"","affiliations":[],"preferred":false,"id":362386,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wright, D.L.","contributorId":88758,"corporation":false,"usgs":true,"family":"Wright","given":"D.L.","email":"","affiliations":[],"preferred":false,"id":362385,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70011990,"text":"70011990 - 1981 - The late-Neoglacial histories of the Agassiz and Jackson glaciers, Glacier National Park, Montana.","interactions":[],"lastModifiedDate":"2017-05-04T16:38:58","indexId":"70011990","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":898,"text":"Arctic and Alpine Research","active":true,"publicationSubtype":{"id":10}},"title":"The late-Neoglacial histories of the Agassiz and Jackson glaciers, Glacier National Park, Montana.","docAbstract":"<p><span>Twenty-one tree-ring stations, totaling 116 trees, were sampled at various localities within the forest trimlines fronting the Agassiz and Jackson glaciers, Glacier National Park, Montana. Tree ages within these zones became progressively younger from the region of the maximum late-Neoglacial position to the bases of the bedrock slopes on which these glaciers are now confined. The age of the oldest tree plus 15 yr was used to estimate the date of glacier withdrawal from a given station. It was found that both the Agassiz and Jackson glaciers began to retreat from their maximum late-Neoglacial positions about 1860. Hence, Matthes's (1940) estimate of glacial advances culminating about 1850 to 1855 for many glaciers in the western United States seems reasonable for the Glacier National Park region. Retreat rates, derived from the tree-ring data, appear to have been modest (&lt;7 m yr<sup>-1</sup>) until about 1910 when they increased reaching more than 40 m yr<sup>-1</sup> for the Agassiz Glacier between 1917 and 1926. Retreat rates after the late 1920s could not be monitored by tree-ring analysis as both glaciers had retreated onto bare bedrock dip slopes. However, from various literature descriptions and National Park Service records, both glaciers experienced rapid retreat (&gt;100 m yr<sup>-1</sup>) from this time until 1932. In addition, while the Agassiz Glacier was monitored by the National Park Service (1932 to 1942) retreat continued at a rapid rate (&gt;90 m yr<sup>-1</sup>). This period of rapid retreat corresponds with a period of above-average summer temperatures and decreased precipitation in the climatic record of the region. Since the mid-1940s the retreat rate of both glaciers has slowed markedly.</span></p>","language":"English","publisher":"INSTAAR, University of Colorado","doi":"10.2307/1551194","usgsCitation":"Carrara, P., and McGimsey, R.G., 1981, The late-Neoglacial histories of the Agassiz and Jackson glaciers, Glacier National Park, Montana.: Arctic and Alpine Research, v. 13, no. 2, p. 183-196, https://doi.org/10.2307/1551194.","productDescription":"14 p.","startPage":"183","endPage":"196","costCenters":[],"links":[{"id":220733,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Montana","otherGeospatial":"Glacier National Park","volume":"13","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bad88e4b08c986b323c93","contributors":{"authors":[{"text":"Carrara, P. E.","contributorId":33727,"corporation":false,"usgs":true,"family":"Carrara","given":"P. E.","affiliations":[],"preferred":false,"id":362461,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McGimsey, R. G.","contributorId":93921,"corporation":false,"usgs":true,"family":"McGimsey","given":"R.","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":362462,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70011856,"text":"70011856 - 1981 - Northwest margin of California continental borderland: Marine geology and tectonic evolution","interactions":[],"lastModifiedDate":"2023-01-12T11:53:35.159296","indexId":"70011856","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":"Northwest margin of California continental borderland: Marine geology and tectonic evolution","docAbstract":"<p>The northwest margin of the California continental borderland consists mainly of two northwest-trending pre-Neogene lithologic belts blanketed by Miocene and younger strata. These belts, which are lithologically and structurally correlated with the Franciscan Complex and Great Valley sequence of northern California, are interpreted to represent facies corresponding to the subduction complex and forearc-basin deposits of a late Mesozoic and Paleogene continental-margin arc-trench system. The outer belt, which forms the acoustic basement underlying the continental slope and Patton Ridge, is characterized by: (1) moderately high compressional velocities (5.1 to 6.2 km/sec), (2) discordant and discontinuous seismic reflectors, and (3) nonfossiliferous and diverse rock types t at range in metamorphic grade from zeolite-bearing arkosic sandstone to blueschist. Landward, the inner Great Valley sequence belt underlies Santa Rosa-Cortes Ridge and Santa Cruz and San Nicolas Basins; in contrast to the outer belt, this belt is characterized by: (1) intermediate compressional velocities (4.5 to 4.6 km/sec), (2) concordant and relatively continuous reflectors, and (3) a thick turbidite sequence of relatively undeformed and unmetamorphosed fossiliferous Cretaceous and Paleogene strata. The inner belt overlies a 6.6-km/sec layer that is probably oceanic crust, a relation consistent with the hypothesis that trapped old oceanic crust underlies the forearc basins along parts of some convergent margins.</p><p>Well-developed wrench-fault structures in overlying Miocene strata record a transition from Paleogene subduction to Neogene transform faulting. Related events include widespread andesitic to dacitic volcanism and concurrent uplift and erosion of Miocene and older rocks. The proximity of these Miocene silicic volcanic rocks to the paleotrench (&lt; 20 km) is best explained as resulting from passage of the southward-migrating Rivera ridge-fault-trench triple junction along the margin. On the basis of the age of the adjacent sea floor, passage of this triple junction occurred about 17 m.y. ago, a date that corresponds closely to the inception of volcanism and uplift in the northwest margin of the borderland. A widespread unconformity that separates highly deformed lower and lower middle iocene strata from relatively undeformed younger strata is assumed to mark the subsequent onset of wrench faulting.</p><p>The timing of volcanism and uplift, and of the slightly younger wrenching event, closely matches the plate-tectonic model of Atwater and Molnar if the northwest margin of the borderland is restored to an earlier tectonic setting off Baja California, approximately 260 km southeast of its present position.</p>","language":"English","publisher":"American Association of Petroleum Geologists","doi":"10.1306/2F9197A1-16CE-11D7-8645000102C1865D","usgsCitation":"Crouch, J., 1981, Northwest margin of California continental borderland: Marine geology and tectonic evolution: American Association of Petroleum Geologists Bulletin, v. 65, no. 2, p. 191-218, https://doi.org/10.1306/2F9197A1-16CE-11D7-8645000102C1865D.","productDescription":"28 p.","startPage":"191","endPage":"218","numberOfPages":"28","costCenters":[],"links":[{"id":220725,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"coordinates\": [\n          [\n            [\n              -118.19125226917674,\n              33.86449981604767\n            ],\n            [\n              -120.63224634312732,\n              33.86449981604767\n            ],\n            [\n              -120.63224634312732,\n              32.238222576392715\n            ],\n            [\n              -118.19125226917674,\n              32.238222576392715\n            ],\n            [\n              -118.19125226917674,\n              33.86449981604767\n            ]\n          ]\n        ],\n        \"type\": \"Polygon\"\n      }\n    }\n  ]\n}","volume":"65","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a684ee4b0c8380cd73726","contributors":{"authors":[{"text":"Crouch, J.K.","contributorId":107694,"corporation":false,"usgs":true,"family":"Crouch","given":"J.K.","email":"","affiliations":[],"preferred":false,"id":362129,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70011854,"text":"70011854 - 1981 - Blast dynamics at Mount St Helens on 18 May 1980","interactions":[],"lastModifiedDate":"2012-03-12T17:18:33","indexId":"70011854","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":"Blast dynamics at Mount St Helens on 18 May 1980","docAbstract":"At 8.32 a.m. on 18 May 1980, failure of the upper part of the north slope of Mount St Helens triggered a lateral eruption ('the blast') that devastated the conifer forests in a sector covering ???500 km2 north of the volcano. I present here a steady flow model for the blast dynamics and propose that through much of the devastated area the blast was a supersonic flow of a complex multiphase (solid, liquid, vapour) mixture. The shape of the blast zone; pressure, temperature, velocity (Mach number) and density distributions within the flow; positions of weak and strong internal shocks; and mass flux, energy flux, and total energy are calculated. The shape of blast zone was determined by the initial areal expansion from the reservoir, by internal expansion and compression waves (including shocks), and by the density of the expanding mixture. The pressure within the flow dropped rapidly away from the source of the blast until, at a distance of ???11 km, the flow became underpressured relative to the surrounding atmosphere. Weak shocks within the flow subparallel to the east and west margins coalesced at about this distance into a strong Mach disk shock, across which the flow velocities would have dropped from supersonic to subsonic as the pressure rose back towards ambient. The positions of the shocks may be reflected in differences in the patterns of felled trees. At the limits of the devastated area, the temperature had dropped only 20% from the reservoir temperature because the entrained solids thermally buffered the flow (the dynamic and thermodynamic effects of the admixture of the surrounding atmosphere and the uprooted forest and soils into the flow are not considered). The density of the flow decreased with distance until, at the limits of the blast zone, 20-25 km from the volcano, the density became comparable with that of the surrounding (dirty) atmosphere and the flow became buoyant and ramped up into the atmosphere. According to the model, the mass flux per unit area at the source was 0.6 ?? 104 g s-1 cm-2 and the energy flux per unit area was 2.5 MW cm-2. From the measured total ejected mass, 0.25 ?? 1015 g, the total energy released during the eruption was 1024 erg or 24 megatons. The model, triggering of the eruption and the transition from unsteady to steady flow, and applications to eyewitness observations and atmospheric effects are discussed in ref. 1. ?? 1981 Nature Publishing Group.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Nature","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1038/291568a0","issn":"00280836","usgsCitation":"Kieffer, S.W., 1981, Blast dynamics at Mount St Helens on 18 May 1980: Nature, v. 291, no. 5816, p. 568-570, https://doi.org/10.1038/291568a0.","startPage":"568","endPage":"570","numberOfPages":"3","costCenters":[],"links":[{"id":205060,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1038/291568a0"},{"id":220723,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"291","issue":"5816","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f1e0e4b0c8380cd4ae95","contributors":{"authors":[{"text":"Kieffer, S. W.","contributorId":19186,"corporation":false,"usgs":true,"family":"Kieffer","given":"S.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":362123,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70011850,"text":"70011850 - 1981 - A review of regional mineral resource assessment methods","interactions":[],"lastModifiedDate":"2024-01-12T17:11:09.746558","indexId":"70011850","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":"A review of regional mineral resource assessment methods","docAbstract":"<p><span>Over 100 papers on regional mineral resource assessment of nonfuels are classified according to method(s) used and form(s) of product in order to help identify possible methods for future assessments. Types of products that have been used include: tons of metal; tons of rock and associated grade; gross value; potential; number of deposits; probability of one or more deposits; tons of rock, grade, and number of deposits by type; potential supply; and net value. Assessment methods considered are: time-rate, crustal abundance, cumulative tonnage versus grade, simple subjective, complex subjective, Bayesian, frequency, trend, geometric probability, multiple regression, discriminant analysis, modified component, multivariate logistic, cluster analysis or pattern recognition, and simulation.Selection of a method to be employed in an assessment should be based on: (1) appropriateness of the product to the problem, (2) limitations in resources, such as information or time available for the assessment, (3) the level of uncertainty and acceptability of biases in the assessment, and (4) the need for verification of results and acceptance of the method.</span></p>","language":"English","publisher":"Society of Economic Geologists","doi":"10.2113/gsecongeo.76.5.1006","issn":"03610128","usgsCitation":"Singer, D., and Mosier, D., 1981, A review of regional mineral resource assessment methods: Economic Geology, v. 76, no. 5, p. 1006-1015, https://doi.org/10.2113/gsecongeo.76.5.1006.","productDescription":"10 p.","startPage":"1006","endPage":"1015","numberOfPages":"10","costCenters":[],"links":[{"id":221698,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"76","issue":"5","noUsgsAuthors":false,"publicationDate":"1981-08-01","publicationStatus":"PW","scienceBaseUri":"5059e556e4b0c8380cd46cc9","contributors":{"authors":[{"text":"Singer, D.A.","contributorId":69128,"corporation":false,"usgs":true,"family":"Singer","given":"D.A.","email":"","affiliations":[],"preferred":false,"id":362113,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mosier, D.L.","contributorId":21965,"corporation":false,"usgs":true,"family":"Mosier","given":"D.L.","email":"","affiliations":[],"preferred":false,"id":362112,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70011977,"text":"70011977 - 1981 - Experimental seawater-basalt interaction at 300°C, 500 bars, chemical exchange, secondary mineral formation and implications for the transport of heavy metals","interactions":[],"lastModifiedDate":"2015-06-10T13:23:30","indexId":"70011977","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Experimental seawater-basalt interaction at 300°C, 500 bars, chemical exchange, secondary mineral formation and implications for the transport of heavy metals","docAbstract":"<p id=\"\">Seawater and NaCl solutions were reacted with basalt (basalt glass and diabase) for several months at 300&deg;C, 500 bars and a water/rock ratio of 10.</p>\n<p id=\"\">During reaction, seawater was significantly modified, increasing in Ca, H<sub>2</sub>S, CO<sub>2</sub>. SiO<sub>2</sub>, K. Fe, Mn. Ba, Al and H<sup>+</sup>, and decreasing in Mg and SO<sub>4</sub>. Basalt glass was completely replaced by smectite, wairakite, anhydrite and hematite, and diabase was partially replaced by mixed layered smectite-chlorite, anhydrite and magnetite (?). Diabase was altered more slowly than basalt glass and the corresponding changes in seawater chemistry were less pronounced.</p>\n<p id=\"\">Basalt glass reacted with a 0.45 m NaCl solution resulted in the formation of smectite, albite. truscottite and wairakite. Solutions from this experiment were characterized by a relatively high pH and dominated by Ca for Na exchange reactions. At no point in this experiment were heavy metals solubilized, in contrast to the seawater experiments. This behavior illustrates the fundamental importance of seawater chemistry to heavy-metal solubility; that is, the removal of Mg from seawater generates acidity which maintains heavy metals in solution. Apparently seawater chlorinity is not capable of enhancing heavy-metal solubility by chloride complexing.</p>\n<p id=\"\">Seafloor heavy-metal deposits can result from the following:</p>\n<ol>\n<li>Seawater-basalt interaction at moderate temperature (&sim;-300&deg;C and high effective water/rock ratios; or</li>\n<li>at relatively high temperatures (&sim;-400&deg;C) and low (e.g.&lt; 10) water/rock ratios.</li>\n</ol>","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(81)90157-5","issn":"00167037","usgsCitation":"Seyfried, W., and Bischoff, J.L., 1981, Experimental seawater-basalt interaction at 300°C, 500 bars, chemical exchange, secondary mineral formation and implications for the transport of heavy metals: Geochimica et Cosmochimica Acta, v. 45, no. 2, p. 135-147, https://doi.org/10.1016/0016-7037(81)90157-5.","productDescription":"13 p.","startPage":"135","endPage":"147","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":221628,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"45","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0ddfe4b0c8380cd53223","contributors":{"authors":[{"text":"Seyfried, W.E. Jr.","contributorId":15347,"corporation":false,"usgs":true,"family":"Seyfried","given":"W.E.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":362422,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bischoff, J. L.","contributorId":28969,"corporation":false,"usgs":true,"family":"Bischoff","given":"J.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":362423,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70011720,"text":"70011720 - 1981 - Electrolytic oxidation of anthracite","interactions":[],"lastModifiedDate":"2023-10-02T17:17:10.933691","indexId":"70011720","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1709,"text":"Fuel","active":true,"publicationSubtype":{"id":10}},"title":"Electrolytic oxidation of anthracite","docAbstract":"<p><span>An anthracite slurry can be oxidized only with difficulty by electrolytic methods in which aqueous electrolytes are used if the slurry is confined to the region of the anode by a porous pot or diaphragm. However, it can be easily oxidized if the anthracite itself is used as the anode. No porous pot or diaphragm is needed. Oxidative consumption of the coal to alkali-soluble compounds is found to proceed preferentially at the edges of the aromatic planes. An oxidation model is proposed in which the chief oxidants are molecular and radical species formed by the electrolytic decomposition of water at the coal surface-electrolyte interface. The oxidation reactions proposed account for the opening of the aromatic rings and the subsequent formation of carboxylic acids. The model also explains the observed anisotropic oxidation and the need for the porous pot or diaphragm used in previous studies of the oxidation of coal slurries.</span></p>","language":"English","publisher":"Elsevier","doi":"10.1016/0016-2361(81)90066-1","issn":"00162361","usgsCitation":"Senftle, F.E., Patton, K., and Heard, I., 1981, Electrolytic oxidation of anthracite: Fuel, v. 60, no. 12, p. 1131-1136, https://doi.org/10.1016/0016-2361(81)90066-1.","productDescription":"6 p.","startPage":"1131","endPage":"1136","costCenters":[],"links":[{"id":221542,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"60","issue":"12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a08a3e4b0c8380cd51bdd","contributors":{"authors":[{"text":"Senftle, F. E.","contributorId":47788,"corporation":false,"usgs":true,"family":"Senftle","given":"F.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":361802,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Patton, K.M.","contributorId":43914,"corporation":false,"usgs":true,"family":"Patton","given":"K.M.","email":"","affiliations":[],"preferred":false,"id":361801,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Heard, I. Jr.","contributorId":95199,"corporation":false,"usgs":true,"family":"Heard","given":"I.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":361803,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70012081,"text":"70012081 - 1981 - Concentration of some platinum-group metals in coal","interactions":[],"lastModifiedDate":"2024-02-24T01:41:31.292194","indexId":"70012081","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2033,"text":"International Journal of Coal Geology","active":true,"publicationSubtype":{"id":10}},"title":"Concentration of some platinum-group metals in coal","docAbstract":"<div id=\"preview-section-abstract\"><div id=\"abstracts\" class=\"Abstracts u-font-serif text-s\"><div id=\"aep-abstract-id4\" class=\"abstract author\"><div id=\"aep-abstract-sec-id5\"><p>New data on some platinum group metals in coal indicate that the concentration of Pt is generally less than about 5 ppb, that of Pd is generally less than 1 ppb, and that of Rh is generally less than 0.5 ppb. No conclusive evidence was obtained concerning the mode of occurrence of these elements in coal.</p></div></div></div></div>","language":"English","publisher":"Elsevier","doi":"10.1016/0166-5162(81)90006-9","issn":"01665162","usgsCitation":"Finkelman, R.B., and Aruscavage, P.J., 1981, Concentration of some platinum-group metals in coal: International Journal of Coal Geology, v. 1, no. 2, p. 95-99, https://doi.org/10.1016/0166-5162(81)90006-9.","productDescription":"5 p.","startPage":"95","endPage":"99","numberOfPages":"5","costCenters":[],"links":[{"id":222634,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"1","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f980e4b0c8380cd4d638","contributors":{"authors":[{"text":"Finkelman, R. B.","contributorId":20341,"corporation":false,"usgs":true,"family":"Finkelman","given":"R.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":362682,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Aruscavage, P. J.","contributorId":41411,"corporation":false,"usgs":true,"family":"Aruscavage","given":"P.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":362683,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70011724,"text":"70011724 - 1981 - An alternative model for the development of the allochthonous southern Appalachian Piedmont","interactions":[],"lastModifiedDate":"2023-02-08T17:54:24.105924","indexId":"70011724","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":732,"text":"American Journal of Science","active":true,"publicationSubtype":{"id":10}},"title":"An alternative model for the development of the allochthonous southern Appalachian Piedmont","docAbstract":"<p>No abstract available.</p>","language":"English","publisher":"American Journal of Science","doi":"10.2475/ajs.281.9.1153","usgsCitation":"Zen, E., 1981, An alternative model for the development of the allochthonous southern Appalachian Piedmont: American Journal of Science, v. 281, no. 9, p. 1153-1163, https://doi.org/10.2475/ajs.281.9.1153.","productDescription":"11 p.","startPage":"1153","endPage":"1163","numberOfPages":"11","costCenters":[],"links":[{"id":221609,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"281","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e9ede4b0c8380cd4852c","contributors":{"authors":[{"text":"Zen, E-An","contributorId":47064,"corporation":false,"usgs":true,"family":"Zen","given":"E-An","email":"","affiliations":[],"preferred":false,"id":361812,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"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":"<p><span>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.</span></p>","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":70011691,"text":"70011691 - 1981 - Sr isotopic tracer study of the Samail ophiolite, Oman","interactions":[],"lastModifiedDate":"2024-07-16T16:33:20.824875","indexId":"70011691","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":"Sr isotopic tracer study of the Samail ophiolite, Oman","docAbstract":"<p><span>We have measured Rb and Sr concentrations and Sr isotopic compositions in 41 whole-rock samples and 12 mineral separates from units of the Samail ophiolite, including peridotite, gabbro, plagiogranite, diabase dikes, and gabbro and websterite dikes within the metamorphic peridotite. Ten samples of cumulate gabbro from the Wadir Kadir section and nine samples from the Wadi Khafifah section have mean&nbsp;</span><sup>87</sup><span>Sr/</span><sup>86</sup><span>Sr ratios and standard deviations of 0.70314 ± 0.00030 and 0.70306 ± 0.00034, respectively. The dispersion in Sr isotopic composition may reflect real heterogeneities in the magma source region. The average Sr isotopic composition of cumulate gabbro falls in the range of isotopic compositions of modern midocean ridge basalt. The&nbsp;</span><sup>87</sup><span>Sr/</span><sup>86</sup><span>Sr ratios of noncumulate gabbro, plagiogranite, and diabase dikes range from 0.7034 to 0.7047, 0.7038 to 0.7046, and 0.7037 to 0.7061, respectively. These higher&nbsp;</span><sup>87</sup><span>Sr/</span><sup>86</sup><span>Sr ratios are due to alteration of initial magmatic compositions by hydrothermal exchange with seawater. Mineral separates from dikes that cut harzburgite tectonite have Sr isotopic compositions which agree with that of cumulate gabbro. These data indicate that the cumulate gabbro and the different dikes were derived from partial melting of source regions that had similar long-term histories and chemical compositions.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB04p02709","issn":"01480227","usgsCitation":"Lanphere, M.A., Coleman, R.G., and Hopson, C., 1981, Sr isotopic tracer study of the Samail ophiolite, Oman: Journal of Geophysical Research Solid Earth, v. 86, no. B4, p. 2709-2720, https://doi.org/10.1029/JB086iB04p02709.","productDescription":"12 p.","startPage":"2709","endPage":"2720","numberOfPages":"12","costCenters":[],"links":[{"id":221058,"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":"505b963de4b08c986b31b3b2","contributors":{"authors":[{"text":"Lanphere, M. A.","contributorId":35298,"corporation":false,"usgs":true,"family":"Lanphere","given":"M.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":361722,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Coleman, R. G.","contributorId":75170,"corporation":false,"usgs":true,"family":"Coleman","given":"R.","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":361723,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hopson, C.A.","contributorId":13244,"corporation":false,"usgs":true,"family":"Hopson","given":"C.A.","email":"","affiliations":[],"preferred":false,"id":361721,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70012106,"text":"70012106 - 1981 - Ne matrix spectra of the sym-C6Br3F3+ radical cation","interactions":[],"lastModifiedDate":"2013-03-12T21:20:50","indexId":"70012106","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1215,"text":"Chemical Physics","active":true,"publicationSubtype":{"id":10}},"title":"Ne matrix spectra of the sym-C6Br3F3+ radical cation","docAbstract":"The electronic absorption and laser excited, wavelength resolved fluorescence spectra of the title cation have been observed in solid Ne matrix and vibrationally analysed. The vibrational structure of the excited B2A2??? state shows close similarity to the parent compound. The X2E??? ground state structure is strongly perturbed and irregular owing to a large Jahn-Teller distortion. The data are analysed in terms of a recently developed, sophisticated multimode Jahn-Teller theoretical model. We have generated the sym-C6Br3F3+ cations in solid Ne matrix and obtained their wavelength resolved emission and absorption spectra. T ground electronic X2E??? state exhibits an irregular and strongly perturbed vibrational structure, which can be successfully modeled using sophisticated multimode Jahn-Teller theory. ?? 1981.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Chemical Physics","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","doi":"10.1016/0301-0104(81)85043-4","issn":"03010104","usgsCitation":"Bondybey, V., Sears, T., Miller, T., Vaughn, C., English, J., and Shiley, R., 1981, Ne matrix spectra of the sym-C6Br3F3+ radical cation: Chemical Physics, v. 61, no. 1-2, p. 9-16, https://doi.org/10.1016/0301-0104(81)85043-4.","startPage":"9","endPage":"16","numberOfPages":"8","costCenters":[],"links":[{"id":221929,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":269232,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0301-0104(81)85043-4"}],"volume":"61","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a63c7e4b0c8380cd726b5","contributors":{"authors":[{"text":"Bondybey, V.E.","contributorId":74879,"corporation":false,"usgs":true,"family":"Bondybey","given":"V.E.","email":"","affiliations":[],"preferred":false,"id":362746,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sears, T.J.","contributorId":51912,"corporation":false,"usgs":true,"family":"Sears","given":"T.J.","email":"","affiliations":[],"preferred":false,"id":362745,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Miller, T.A.","contributorId":49926,"corporation":false,"usgs":true,"family":"Miller","given":"T.A.","email":"","affiliations":[],"preferred":false,"id":362744,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Vaughn, C.","contributorId":23689,"corporation":false,"usgs":true,"family":"Vaughn","given":"C.","email":"","affiliations":[],"preferred":false,"id":362741,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"English, J.H.","contributorId":28746,"corporation":false,"usgs":true,"family":"English","given":"J.H.","email":"","affiliations":[],"preferred":false,"id":362742,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Shiley, R.S.","contributorId":37899,"corporation":false,"usgs":true,"family":"Shiley","given":"R.S.","affiliations":[],"preferred":false,"id":362743,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}}
]}