An ion microprobe mass analyzer (IMMA) has been used to analyze semi-quantitatively mineral-rich coal particles from two separate facies of the Upper Freeport coal bed. Accuracy is estimated to be ∓ 20% for those elements making up more than 0.1 wt.% of the particles and ∓ 50% for elements making up less than 0.1 wt.%. Using IMMA data, we found statistically significant differences between the two samples for five (Fe, Ca, Mn, Li, Ce) of the 25 elements detected. For Li and Mn the differences between the mineral-rich particles within samples were similar to differences found between samples on a whole-coal basis. For Ca and Fe, the differences are attributed to different modes of occurrence, and for Ce, the differences are probably due to an irregular distribution of an inorganic phase. We conclude that the IMMA can be used to obtain semi-quantitative data that may provide insight into the distribution and mode of occurrence of some of the elements in coal.
Solutions of 30% H2O2 ranging from pH = 0 to pH = 11.5 have been used to oxidize anthracite at room temperature. The inorganic impurities, primarily pyrite, catalysed the oxidation and reduction of H2O2 (the Fenton reaction) to form the hydroxyl radical; the oxidation of the organic matter was minimal and was observed only in strong acidic solutions (pH < 1.5). After acid demineralization, samples of the same anthracite underwent a significant enhancement of oxidation in both acid and alkaline solutions (pH = 0.4–11.5). As all the iron had been removed from the surface and the reactions were completed in a much shorter time, the oxidation mechanism must have been of a different nature than that for the untreated anthracite. A qualitative model based on the catalytic decomposition of H2O2 by activated carbon sites in the coal surface is used to explain the oxidation of the demineralized anthracite.
","language":"English","publisher":"Elsevier","doi":"10.1016/0016-2361(84)90041-3","issn":"00162361","usgsCitation":"Heard, I., and Senftle, F.E., 1984, Chemical oxidation of anthracite with hydrogen peroxide via the Fenton reaction: Fuel, v. 63, no. 2, p. 221-226, https://doi.org/10.1016/0016-2361(84)90041-3.","productDescription":"6 p.","startPage":"221","endPage":"226","costCenters":[],"links":[{"id":220630,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"63","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f581e4b0c8380cd4c27f","contributors":{"authors":[{"text":"Heard, I.","contributorId":28362,"corporation":false,"usgs":true,"family":"Heard","given":"I.","affiliations":[],"preferred":false,"id":365517,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Senftle, F. E.","contributorId":47788,"corporation":false,"usgs":true,"family":"Senftle","given":"F.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":365518,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70013194,"text":"70013194 - 1984 - Changing patterns of Pennsylvanian coal-swamp vegetation and implications of climatic control on coal occurrence","interactions":[],"lastModifiedDate":"2024-02-24T01:31:04.407339","indexId":"70013194","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","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":"Changing patterns of Pennsylvanian coal-swamp vegetation and implications of climatic control on coal occurrence","docAbstract":"Improved regional and interregional stratigraphic correlations of Pennsylvanian strata permit comparisons of vegetational changes in Euramerican coal swamps. The coal-swamp vegetation is known directly from in situ coal-ball peat deposits from more than 65 coals in the United States and Europe. Interpretations of coal-swamp floras on the basis of coal-ball peat studies are extended to broader regional and stratigraphic patterns by use of coal palynology. Objectives of the quantitative analyses of the vegetation in relation to coal are to determine the botanical constituents at the peat stage and their environmental implications for plant growth and peat accumulation. Morphological and paleoecological analyses provide a basis for deducing freshwater regimes of coal swamps.
Changes in composition of Pennsylvanian coal-swamp vegetation are quire similar from one paralic coal region to another and show synchrony that is attributable to climate. Paleobotany and paleogeography of the Euramerican province indicate a moist tropical paleoclimate. Rainfall, runoff and evapotranspiration were the variable climatic controls in the distribution of coal-swamp vegetation, peat accumulation and coal resources. In relative terms of climatic wetness the Pennsylvanian Period is divisible into five intervals, which include two relatively drier intervals that developed during the Lower-Middle and Middle-Upper Pennsylvanian transitions. The climate during Early Pennsylvanian time was moderately wet and the median in moisture availability. Early Middle Pennsylvanian was drier, probably seasonally dry-wet; late Middle Pennsylvanian was the wettest in the Midcontinent; early Late Pennsylvanian was the driest; and late Late Pennsylvanian was probably the wettest in the Dunkard Basin. The five climatic intervals represent a general means of dividing coal resources within each region into groups with similar botanical constituents and environments of peat accumulation. Regional differences in basinal geology and climate were significant variables, but the synchronous control of paleoclimate was of primary importance.
Application of partial dissolution techniques to geochemical exploration has advanced from an early empirical approach to an approach based on sound geochemical principles. This advance assures a prominent future position for the use of these techniques in geochemical exploration for concealed mineral deposits. Partial dissolution techniques are classified as single dissolution or sequential multiple dissolution depending on the number of steps taken in the procedure, or as “nonselective” extraction and as “selective” extraction in terms of the relative specificity of the extraction. The choice of dissolution techniques for use in geochemical exploration is dictated by the geology of the area, the type and degree of weathering, and the expected chemical forms of the ore and of the pathfinding elements. Case histories have illustrated many instances where partial dissolution techniques exhibit advantages over conventional methods of chemical analysis used in geochemical exploration.
","language":"English","publisher":"Elsevier","doi":"10.1016/0375-6742(84)90078-5","issn":"03756742","usgsCitation":"Chao, T.T., 1984, Use of partial dissolution techniques in geochemical exploration: Journal of Geochemical Exploration, v. 20, no. 2, p. 101-135, https://doi.org/10.1016/0375-6742(84)90078-5.","productDescription":"35 p.","startPage":"101","endPage":"135","numberOfPages":"35","costCenters":[],"links":[{"id":220414,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"20","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bbf53e4b08c986b329abe","contributors":{"authors":[{"text":"Chao, T. T.","contributorId":31900,"corporation":false,"usgs":true,"family":"Chao","given":"T.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":365487,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70013180,"text":"70013180 - 1984 - Accretionary lapilli in altered tuffs associated with coal beds","interactions":[],"lastModifiedDate":"2024-05-21T23:28:50.997658","indexId":"70013180","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2450,"text":"Journal of Sedimentary Petrology","active":true,"publicationSubtype":{"id":10}},"title":"Accretionary lapilli in altered tuffs associated with coal beds","docAbstract":"Accretionary lapilli have been identified in claystones (tonsteins) associated with coal beds of Late Cretaceous age in Wyoming, Utah, and New Mexico. The presence of accretionary lapilli in these tonstein partings confirms their volcanic origin. Similar concentric structures in other claystones not in coal, such as some flint clays, may also be accretionary lapilli, indicating a volcanic origin for these deposits. The lapilli are spherical aggregates of volcanic ash that form in eruption columns, where water vapor and turbulence promote accretion of layers of fine ash about coarse-grained aggregates of ash acting as nuclei. The very fine particle size of the crystalline components of the claystones containing accretionary lapilli, coupled with the relatively small size of the lapilli themselves (2-7.5 mm), suggests that the lapilli formed far downwind from the volcano through interaction with moisture from the atmosphere, rather than with magmatic or phreatic moisture near the source vent.
Size and density separates of low-temperature-ashed coal from the Powhatan No. 6 mine, Ohio, have been used to determine the mode of occurrence of 28 minor and trace elements in coal. The size distribution of the major minerals has been determined, and correlations of trace elements with major minerals have been made. The role of minor minerals in the mode of occurrence of trace elements is also discussed. Instrumental-neutron-activation analysis was used to determine elemental concentrations, and X-ray diffraction and scanning electron microscopy were used for mineral identification.
","language":"English","publisher":"Elsevier","doi":"10.1016/0016-2361(84)90007-3","issn":"00162361","usgsCitation":"Palmer, C., and Filby, R., 1984, Distribution of trace elements in coal from the Powhatan No. 6 mine, Ohio: Fuel, v. 63, no. 3, p. 318-328, https://doi.org/10.1016/0016-2361(84)90007-3.","productDescription":"11 p.","startPage":"318","endPage":"328","costCenters":[],"links":[{"id":220183,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Ohio","otherGeospatial":"Powhatan No. 6 Mine","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -80.97002633381553,\n 39.899285314443205\n ],\n [\n -80.97002633381553,\n 39.898444085762804\n ],\n [\n -80.96803387008336,\n 39.898444085762804\n ],\n [\n -80.96803387008336,\n 39.899285314443205\n ],\n [\n -80.97002633381553,\n 39.899285314443205\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"63","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a030ce4b0c8380cd50301","contributors":{"authors":[{"text":"Palmer, C.A.","contributorId":81894,"corporation":false,"usgs":true,"family":"Palmer","given":"C.A.","email":"","affiliations":[],"preferred":false,"id":365445,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Filby, R.H.","contributorId":26071,"corporation":false,"usgs":true,"family":"Filby","given":"R.H.","email":"","affiliations":[],"preferred":false,"id":365444,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70013163,"text":"70013163 - 1984 - The continental slope off New England: A long-range sidescan-sonar perspective","interactions":[],"lastModifiedDate":"2018-01-30T19:15:43","indexId":"70013163","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","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":"The continental slope off New England: A long-range sidescan-sonar perspective","docAbstract":"The first continuous overview of a large segment of the continental slope and rise off the northeastern United States has been obtained using the GLORIA II long-range sidescan-sonar system. Extensive dissection by canyon and gully systems and evidence of possible large-scale sediment sliding are seen on the slope. The style and degree of incision, as well as the numbers and locations of canyons, have been found to differ significantly from previously published maps. It is suggested that the slope is a significant source of the sediment that has been deposited on the rise, and that some abrupt changes in the courses of canyons may be the result of local structural control.
","language":"English","publisher":"Springer","doi":"10.1007/BF02237966","usgsCitation":"Scanlon, K.M., 1984, The continental slope off New England: A long-range sidescan-sonar perspective: Geo-Marine Letters, v. 4, no. 1, p. 1-4, https://doi.org/10.1007/BF02237966.","productDescription":"4 p.","startPage":"1","endPage":"4","costCenters":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":220182,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"Georges Bank","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -72.09228515625,\n 38.08268954483802\n ],\n [\n -64.16015624999999,\n 38.08268954483802\n ],\n [\n -64.16015624999999,\n 42.84375132629021\n ],\n [\n -72.09228515625,\n 42.84375132629021\n ],\n [\n -72.09228515625,\n 38.08268954483802\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"4","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baa5ae4b08c986b3227e6","contributors":{"authors":[{"text":"Scanlon, Kathryn M.","contributorId":6816,"corporation":false,"usgs":true,"family":"Scanlon","given":"Kathryn","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":365443,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70013161,"text":"70013161 - 1984 - Sampling design optimization for spatial functions","interactions":[],"lastModifiedDate":"2012-03-12T17:18:36","indexId":"70013161","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2554,"text":"Journal of the International Association for Mathematical Geology","active":true,"publicationSubtype":{"id":10}},"title":"Sampling design optimization for spatial functions","docAbstract":"A new procedure is presented for minimizing the sampling requirements necessary to estimate a mappable spatial function at a specified level of accuracy. The technique is based on universal kriging, an estimation method within the theory of regionalized variables. Neither actual implementation of the sampling nor universal kriging estimations are necessary to make an optimal design. The average standard error and maximum standard error of estimation over the sampling domain are used as global indices of sampling efficiency. The procedure optimally selects those parameters controlling the magnitude of the indices, including the density and spatial pattern of the sample elements and the number of nearest sample elements used in the estimation. As an illustration, the network of observation wells used to monitor the water table in the Equus Beds of Kansas is analyzed and an improved sampling pattern suggested. This example demonstrates the practical utility of the procedure, which can be applied equally well to other spatial sampling problems, as the procedure is not limited by the nature of the spatial function. ?? 1984 Plenum Publishing Corporation.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of the International Association for Mathematical Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Kluwer Academic Publishers-Plenum Publishers","doi":"10.1007/BF01029887","issn":"00205958","usgsCitation":"Olea, R., 1984, Sampling design optimization for spatial functions: Journal of the International Association for Mathematical Geology, v. 16, no. 4, p. 369-392, https://doi.org/10.1007/BF01029887.","startPage":"369","endPage":"392","numberOfPages":"24","costCenters":[],"links":[{"id":205013,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF01029887"},{"id":220180,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"16","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ab07be4b0c8380cd87b23","contributors":{"authors":[{"text":"Olea, Ricardo A. 0000-0003-4308-0808","orcid":"https://orcid.org/0000-0003-4308-0808","contributorId":26436,"corporation":false,"usgs":true,"family":"Olea","given":"Ricardo A.","affiliations":[{"id":241,"text":"Eastern Energy Resources Science Center","active":true,"usgs":true}],"preferred":false,"id":365440,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70013160,"text":"70013160 - 1984 - Determination of rare-earth elements, yttrium and scandium in manganese nodules by inductively-coupled argon-plastma emission spectrometry","interactions":[],"lastModifiedDate":"2023-03-07T16:20:14.320241","indexId":"70013160","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","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":"Determination of rare-earth elements, yttrium and scandium in manganese nodules by inductively-coupled argon-plastma emission spectrometry","docAbstract":"A sequential-scanning, inductively-coupled argon plasma emission spectrometer is used for the determination of the rare-earth elements, plus yttrium and scandium, in manganese nodules. Wavelength selection is optimized to minimize spectral interferences from manganese nodule components. Samples are decomposed with mixed acids in a sealed polycarbonate vessel, and elements are quantified without further treatment. Results for U.S. Geological Survey manganese nodule standards A-1 and P-1 had average relative standard deviations of 6.8% and 8.1%, respectively, and results were in good agreement with those obtained by other methods.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0003-2670(00)84307-X","usgsCitation":"Fries, T.L., Lamothe, P.J., and Pesek, J.J., 1984, Determination of rare-earth elements, yttrium and scandium in manganese nodules by inductively-coupled argon-plastma emission spectrometry: Analytica Chimica Acta, v. 159, no. C, p. 329-336, https://doi.org/10.1016/S0003-2670(00)84307-X.","productDescription":"8 p.","startPage":"329","endPage":"336","numberOfPages":"8","costCenters":[],"links":[{"id":220129,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"159","issue":"C","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ffc0e4b0c8380cd4f398","contributors":{"authors":[{"text":"Fries, Terry L.","contributorId":76349,"corporation":false,"usgs":true,"family":"Fries","given":"Terry","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":365439,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lamothe, Paul J","contributorId":118580,"corporation":false,"usgs":true,"family":"Lamothe","given":"Paul","email":"","middleInitial":"J","affiliations":[],"preferred":false,"id":365437,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Pesek, J. J.","contributorId":78872,"corporation":false,"usgs":false,"family":"Pesek","given":"J.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":365438,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70013158,"text":"70013158 - 1984 - Magmatic inclusions in rhyolites, contaminated basalts, and compositional zonation beneath the Coso volcanic field, California","interactions":[],"lastModifiedDate":"2018-10-24T15:10:55","indexId":"70013158","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1336,"text":"Contributions to Mineralogy and Petrology","active":true,"publicationSubtype":{"id":10}},"title":"Magmatic inclusions in rhyolites, contaminated basalts, and compositional zonation beneath the Coso volcanic field, California","docAbstract":"Basaltic lava flows and high-silica rhyolite domes form the Pleistocene part of the Coso volcanic field in southeastern California. The distribution of vents maps the areal zonation inferred for the upper parts of the Coso magmatic system. Subalkalic basalts (<50% SiO2) were erupted well away from the rhyolite field at any given time. Compositional variation among these basalts can be ascribed to crystal fractionation. Erupted volumes of these basalts decrease with increasing differentiation. Mafic lavas containing up to 58% SiO2, erupted adjacent to the rhyolite field, formed by mixing of basaltic and silicic magma. Basaltic magma interacted with crustal rocks to form other SiO2-rich mafic lavas erupted near the Sierra Nevada fault zone.
Several rhyolite domes in the Coso volcanic field contain sparse andesitic inclusions (55–61% SiO2). Pillow-like forms, intricate commingling and local diffusive mixing of andesite and rhyolite at contacts, concentric vesicle distribution, and crystal morphologies indicative of undercooling show that inclusions were incorporated in their rhyolitic hosts as blobs of magma. Inclusions were probably dispersed throughout small volumes of rhyolitic magma by convective (mechanical) mixing. Inclusion magma was formed by mixing (hybridization) at the interface between basaltic and rhyolitic magmas that coexisted in vertically zoned igneous systems. Relict phenocrysts and the bulk compositions of inclusions suggest that silicic endmembers were less differentiated than erupted high-silica rhyolite. Changes in inferred endmembers of magma mixtures with time suggest that the steepness of chemical gradients near the silicic/mafic interface in the zoned reservoir may have decreased as the system matured, although a high-silica rhyolitic cap persisted.
The Coso example is an extreme case of large thermal and compositional contrast between inclusion and host magmas; lesser differences between intermediate composition magmas and inclusions lead to undercooling phenomena that suggest smaller ΔT. Vertical compositional zonation in magma chambers has been documented through study of products of voluminous pyroclastic eruptions. Magmatic inclusions in volcanic rocks provide evidence for compositional zonation and mixing processes in igneous systems when only lava is erupted.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Contributions to Mineralogy and Petrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Springer-Verlag","doi":"10.1007/BF01150292","issn":"00107999","usgsCitation":"Bacon, C., and Metz, J., 1984, Magmatic inclusions in rhyolites, contaminated basalts, and compositional zonation beneath the Coso volcanic field, California: Contributions to Mineralogy and Petrology, v. 85, no. 4, p. 346-365, https://doi.org/10.1007/BF01150292.","productDescription":"20 p.","startPage":"346","endPage":"365","numberOfPages":"20","costCenters":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"links":[{"id":205009,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF01150292"},{"id":220127,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","volume":"85","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a4b47e4b0c8380cd69411","contributors":{"authors":[{"text":"Bacon, C. R. 0000-0002-2165-5618","orcid":"https://orcid.org/0000-0002-2165-5618","contributorId":21522,"corporation":false,"usgs":true,"family":"Bacon","given":"C. R.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"preferred":false,"id":365431,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Metz, J.","contributorId":59942,"corporation":false,"usgs":true,"family":"Metz","given":"J.","email":"","affiliations":[],"preferred":false,"id":365432,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70013157,"text":"70013157 - 1984 - Periodic jökulhlaups from Pleistocene glacial Lake Missoula-New evidence from varved sediment in northern Idaho and Washington","interactions":[],"lastModifiedDate":"2015-06-05T13:41:51","indexId":"70013157","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3218,"text":"Quaternary Research","active":true,"publicationSubtype":{"id":10}},"title":"Periodic jökulhlaups from Pleistocene glacial Lake Missoula-New evidence from varved sediment in northern Idaho and Washington","docAbstract":"Newly examined exposures in northern Idaho and Washington show that catastrophic floods from glacial Lake Missoula during late Wisconsin time were repeated, brief jökulhlaups separated by decades of quiet glaciolacustrine and subaerial conditions. Glacial Priest Lake, dammed in the Priest River valley by a tongue of the Purcell trench lobe of the Cordilleran ice sheet, generally accumulated varved mud; the varved mud is sharply interrupted by 14 sand beds deposited by upvalley-running currents. The sand beds are texturally and structurally similar to slackwater sediment in valleys in southern Washington that were backflooded by outbursts from glacial Lake Missoula. Beds of varved mud also accumulated in glacial Lake Spokane (or Columbia?) in Latah Creek valley and elsewhere in northeastern Washington; the mud beds were disrupted, in places violently, during emplacement of each of 16 or more thick flood-gravel beds. This history corroborates evidence from southern Washington that only one graded bed is deposited per flood, refuting a conventional idea that many beds accumulated per flood. The total number of such floodlaid beds in stratigraphic succession near Spokane is at least 28. The mud beds between most of the floodlaid beds in these valleys each consist of between 20 and 55 silt-to-clay varves. Lacustrine environments in northern Idaho and Washington therefore persisted for two to six decades between regularly recurring, colossal floods from glacial Lake Missoula.
","language":"English","publisher":"Elsevier","doi":"10.1016/0033-5894(84)90005-X","issn":"00335894","usgsCitation":"Waitt, R.B., 1984, Periodic jökulhlaups from Pleistocene glacial Lake Missoula-New evidence from varved sediment in northern Idaho and Washington: Quaternary Research, v. 22, no. 1, p. 46-58, https://doi.org/10.1016/0033-5894(84)90005-X.","productDescription":"13 p.","startPage":"46","endPage":"58","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":219782,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":266554,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0033-5894(84)90005-X"}],"volume":"22","issue":"1","noUsgsAuthors":false,"publicationDate":"2017-01-20","publicationStatus":"PW","scienceBaseUri":"505a769ae4b0c8380cd781f1","contributors":{"authors":[{"text":"Waitt, Richard B. 0000-0002-6392-5604 waitt@usgs.gov","orcid":"https://orcid.org/0000-0002-6392-5604","contributorId":2343,"corporation":false,"usgs":true,"family":"Waitt","given":"Richard","email":"waitt@usgs.gov","middleInitial":"B.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"preferred":true,"id":365430,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70013156,"text":"70013156 - 1984 - Santaclaraite, a new calcium-manganese silicate hydrate from California.","interactions":[],"lastModifiedDate":"2012-03-12T17:18:26","indexId":"70013156","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":738,"text":"American Mineralogist","active":true,"publicationSubtype":{"id":10}},"title":"Santaclaraite, a new calcium-manganese silicate hydrate from California.","docAbstract":"Santaclaraite, ideally CaMn4(Si5O14(OH))(OH).H2O, occurs as pink and tan veins and masses in Franciscan chert in the Diablo Range, Santa Clara and Stanislaus counties, California. It is associated with four unidentified Mn silicates, Mn-howieite, quartz, braunite, calcite, rhodochrosite, kutnahorite, baryte, harmotome, chalcopyrite and native copper. Santaclaraite is triclinic, space group B1, a 15.633(1), b 7.603(1) , c 12.003(1) A, alpha 109.71(1)o, beta 88.61(1)o, gamma 99.95(1) o, V 1322.0(3) A3; Z = 4. The strongest lines of the X-ray pattern are 7.04(100), 3.003(84), 3.152(80), 7.69(63), 3.847(57) A. Crystals are lamellar to prismatic (flattened on (100)), with good cleavage on (100) and (010); H. 61/2 Dcalc. 3.398 g/cm3, Dmeas. 3.31 (+ or -0.01); optically biaxial negative, alpha 1.681, beta 1.696, gamma 1.708 (all + or - 0.002), 2Valpha 83 (+ or -1)o. Although chemically a hydrated rhodonite, santaclaraite dehydrates to Mn-bustamite at approx 550oC (in air) . Santaclaraite is a five-tetrahedral-repeat single-chain silicate and has structural affinities with rhodonite, nambulite, marsturite, babingtonite and inesite.-J.A.Z.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"American Mineralogist","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"0003004X","usgsCitation":"Erd, R.C., and Ohashi, Y., 1984, Santaclaraite, a new calcium-manganese silicate hydrate from California.: American Mineralogist, v. 69, no. 1-2, p. 200-206.","startPage":"200","endPage":"206","numberOfPages":"7","costCenters":[],"links":[{"id":219781,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"69","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b86bbe4b08c986b3160d2","contributors":{"authors":[{"text":"Erd, Richard C.","contributorId":89899,"corporation":false,"usgs":true,"family":"Erd","given":"Richard","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":365429,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ohashi, Y.","contributorId":64382,"corporation":false,"usgs":true,"family":"Ohashi","given":"Y.","email":"","affiliations":[],"preferred":false,"id":365428,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70013155,"text":"70013155 - 1984 - Geophysical methods as mapping tools in a strata-bound gold deposit: Haile mine, South Carolina slate belt","interactions":[],"lastModifiedDate":"2024-01-09T00:05:37.078597","indexId":"70013155","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","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":"Geophysical methods as mapping tools in a strata-bound gold deposit: Haile mine, South Carolina slate belt","docAbstract":"Very low frequency electromagnetic, magnetic, and induced polarization methods. The very low frequency electromagnetic resistivity data show high resistivity zones that correlate with siliceous units known to host the gold. The magnetic data clearly identify the mafic and ultramafic dikes which cut metasediments and also fill faults that offset them. The induced polarization method allows examination of the mineralized metasediments in two dimensions by giving vertical sections of resistivity and percent frequency effect, parameters which correlate with silica and pyrite content, respectively. Lithologic units as well as ore zones can thus be mapped in this terrain which is deeply weathered and partially covered by coastal plain sediments.
","language":"English","publisher":"Society of Economic Geologists","doi":"10.2113/gsecongeo.79.2.382","issn":"03610128","usgsCitation":"Wynn, J.C., and Luce, R., 1984, Geophysical methods as mapping tools in a strata-bound gold deposit: Haile mine, South Carolina slate belt: Economic Geology, v. 79, no. 2, p. 382-388, https://doi.org/10.2113/gsecongeo.79.2.382.","productDescription":"7 p.","startPage":"382","endPage":"388","numberOfPages":"7","costCenters":[],"links":[{"id":219780,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"79","issue":"2","noUsgsAuthors":false,"publicationDate":"1984-04-01","publicationStatus":"PW","scienceBaseUri":"505a2862e4b0c8380cd5a097","contributors":{"authors":[{"text":"Wynn, J. C.","contributorId":38544,"corporation":false,"usgs":true,"family":"Wynn","given":"J.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":365426,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Luce, R.W.","contributorId":39862,"corporation":false,"usgs":true,"family":"Luce","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":365427,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70013153,"text":"70013153 - 1984 - Time and the crystallization of apatite in seawater","interactions":[],"lastModifiedDate":"2024-03-19T16:13:04.660908","indexId":"70013153","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","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":"Time and the crystallization of apatite in seawater","docAbstract":"Carbonate fluorapatite has been synthesized in seawater in an experiment of nearly 10-years duration. The addition of phosphate to seawater whose fluoride concentration had been increased to 7.6 mg/l brought about an initial amorphous phosphate precipitate. After 20 months, a crystalline magnesium phosphate phase developed within the amorphous phosphate. Crystallization of apatite, which occurred during the last 3 years of the experiment, was accompanied by dissolution of the crystalline magnesium phosphate phase.
The MgO content of the apatite (1.9 percent) is high in comparison to Tertiary and older apatite but similar to some young apatite; the CO2 content (3.6 percent) is medium, and the fluorine content (2.2 percent) is low but again similar to some young apatite. The hydroxyl ion (OH−) likely fills the need for additional fluorine-position atoms. The mole ratio of Ca plus substituent elements to P plus substituent elements (1.50) is low in comparison to the expected ratio of 1.67. The substitution of the hydronium ion (H3O+) for Ca may account for this difference.
The synthesis of apatite in seawater demonstrates that the factor of time overcomes the well known inhibiting effect of magnesium upon the crystallization of apatite. It also implies that given an adequate supply of phosphate, apatite can form in most ocean environments and likely plays a major pan in the control of the phosphate content of seawater.
","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(84)90365-X","issn":"00167037","usgsCitation":"Gulbrandsen, R.A., Roberson, C.E., and Neil, S., 1984, Time and the crystallization of apatite in seawater: Geochimica et Cosmochimica Acta, v. 48, no. 1, p. 213-218, https://doi.org/10.1016/0016-7037(84)90365-X.","productDescription":"6 p.","startPage":"213","endPage":"218","numberOfPages":"6","costCenters":[],"links":[{"id":220627,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"48","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb392e4b08c986b325e8b","contributors":{"authors":[{"text":"Gulbrandsen, R. A.","contributorId":48543,"corporation":false,"usgs":true,"family":"Gulbrandsen","given":"R.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":365422,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Roberson, C. E.","contributorId":40190,"corporation":false,"usgs":true,"family":"Roberson","given":"C.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":365421,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Neil, S.T.","contributorId":27444,"corporation":false,"usgs":true,"family":"Neil","given":"S.T.","email":"","affiliations":[],"preferred":false,"id":365420,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70013150,"text":"70013150 - 1984 - Gases and trace elements in soils at the North Silver Bell deposit, Pima County, Arizona","interactions":[],"lastModifiedDate":"2025-03-07T16:35:25.785604","indexId":"70013150","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","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":"Gases and trace elements in soils at the North Silver Bell deposit, Pima County, Arizona","docAbstract":"Reconstruction of some aspects of the initial environment of ore deposition through detailed S, C, and O isotope studies of the Fowler orebody, and through reconnaissance trace element and S isotope studies of sphalerite concentrates and composite samples of ore from 22 orebodies; and (2) evaluation of the effects of high-grade metamorphism on the stable isotope geochemistry of both the ore and gangue minerals of a massive sulfide orebody. The delta 34 S values of pyrite, sphalerite, and galena in the Fowler orebody range from 11.5 to 17.5 per mil; anhydrite associated with ore ranges from 25.6 to 27.0 per mil. Average equilibration temperatures calculated from the delta 34 S differences between coexisting sulfur-bearing phases are 388 degrees C for pyrite-sphalerite, 338 degrees C for sphalerite-galena, 329 degrees C for pyrite-galena, and 602 degrees C for anhydrite-pyrite; all pairs display narrow temperature distributions. The delta 13 C and delta 18 O values of carbonates from the Fowler orebody range from -1.6 to 1.4 per mil and from 24.8 to 27.0 per mil, respectively; quartz delta 18 O values range from 23.0 to 27.0 per mil. The delta 34 S values of sphalerite concentrated from composite samples of the orebodies range from 12.7 to 14.7 per mil. This narrow range contrasts sharply with the wide variability of associated evaporitic anhydrite lenses, which range from 8 to 28 per mil. A stratigraphic increase in the delta 34 S value of the evaporitic anhydrite at Balmat, and large sulfide iron-formation occurrences near Balmat, imply that bacterial sulfate reduction occurred on an unusually large scale during Balmat sedimentation. The presence of such an increase in a sedimentary section may constitute a valuable exploration guide.
","language":"English","publisher":"Society of Economic Geologists","doi":"10.2113/gsecongeo.79.2.239","issn":"03610128","usgsCitation":"Whelan, J.F., Rye, R.O., and Delorraine, W., 1984, The Balmat-Edwards zinc-lead deposits; synsedimentary ore from Mississippi Valley-type fluids: Economic Geology, v. 79, no. 2, p. 239-265, https://doi.org/10.2113/gsecongeo.79.2.239.","productDescription":"27 p.","startPage":"239","endPage":"265","numberOfPages":"27","costCenters":[],"links":[{"id":220518,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"79","issue":"2","noUsgsAuthors":false,"publicationDate":"1984-04-01","publicationStatus":"PW","scienceBaseUri":"505ba693e4b08c986b3211f0","contributors":{"authors":[{"text":"Whelan, J. F.","contributorId":45328,"corporation":false,"usgs":true,"family":"Whelan","given":"J.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":365398,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rye, R. O.","contributorId":66208,"corporation":false,"usgs":true,"family":"Rye","given":"R.","email":"","middleInitial":"O.","affiliations":[],"preferred":false,"id":365399,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Delorraine, W.","contributorId":12617,"corporation":false,"usgs":true,"family":"Delorraine","given":"W.","email":"","affiliations":[],"preferred":false,"id":365397,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70013144,"text":"70013144 - 1984 - Catastrophic isotopic modification of rhyolitic magma at times of caldera subsidence, Yellowstone Plateau Volcanic Field","interactions":[],"lastModifiedDate":"2024-06-27T16:53:21.29494","indexId":"70013144","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","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":"Catastrophic isotopic modification of rhyolitic magma at times of caldera subsidence, Yellowstone Plateau Volcanic Field","docAbstract":"The Yellowstone Plateau volcanic field has undergone repeated eruption of rhyolitic magma strongly depleted in 18O. Large calderas subsided 2.0, 1.3, and 0.6 Ma ago, on eruption of ash flow sheets that represent at least 2500, 280, and 1000 km3 of zoned magma. More than 60 other rhyolite lavas and tuffs permit reconstruction of the long-term chemical and isotopic evolution of the silicic system. Narrow δ18O ranges in the ash flow sheets contrast with wide δ18O variations in postcaldera lavas of the first and third caldera cycles. Earliest postcollapse lavas are 3 to 6‰ lighter than the preceding ash flow sheets. The O18 depletions were short-lived events that immediately followed caldera subsidence; hundreds of cubic kilometers of magma were drastically 18O depleted and thousands were depleted by 1–2‰. Sequences of postcaldera lavas record partial recovery toward precaldera δ18O values; secular trends between collapse events thus reflect gradual reenrichment of the roofmost magma in δ18O. Much of the subcaldera reservoir was affected, because lavas that erupted as far apart as 115 km reflect the same pattern of depletion and partial recovery. Contemporaneous extracaldera rhyolites have the highest δ18O values in the volcanic field and show no effects of the repeated depletions. Sr and Pb isotope ratios of intracaldera rhyolites jump to more radiogenic values at times of caldera formation and show a longterm zigzag pattern like that of δ18O. Although some contamination by foundering roof rocks seenis to be required, water was probably the predominant contaminant. Even if roof rocks had been strongly depleted in O18 before engulfment, their assimilation would have been far from sufficient to account for the large O18 shift. The low- O18 lavas contain no xenocrysts and show no trace element or phenocryst evidence of massive contamination. Their Fe-Ti-oxide temperatures indicate no cooling relative to the caldera-forming ash flow magma, and their whole-rock, glass, and phenoeryst chemistry suggests compositional continuity with the ash flow sequence. Oxygen exchange between the magma and a mass of low-O18 water greatly exceeding solubility limits may require (1) recurrent explosive activity to sustain access and mixing of water with the magma and (2) convection of the magma reservoir to prevent local saturation.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB089iB10p08339","issn":"01480227","usgsCitation":"Hildreth, W., Christiansen, R., and O’Neil, J.R., 1984, Catastrophic isotopic modification of rhyolitic magma at times of caldera subsidence, Yellowstone Plateau Volcanic Field: Journal of Geophysical Research Solid Earth, v. 89, no. B10, p. 8339-8369, https://doi.org/10.1029/JB089iB10p08339.","productDescription":"31 p.","startPage":"8339","endPage":"8369","numberOfPages":"31","costCenters":[],"links":[{"id":220517,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"89","issue":"B10","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"5059f3c9e4b0c8380cd4b961","contributors":{"authors":[{"text":"Hildreth, W. 0000-0002-7925-4251","orcid":"https://orcid.org/0000-0002-7925-4251","contributorId":100487,"corporation":false,"usgs":true,"family":"Hildreth","given":"W.","affiliations":[],"preferred":false,"id":365396,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Christiansen, R.L. 0000-0002-8017-3918","orcid":"https://orcid.org/0000-0002-8017-3918","contributorId":25565,"corporation":false,"usgs":true,"family":"Christiansen","given":"R.L.","affiliations":[],"preferred":false,"id":365394,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"O’Neil, J. R.","contributorId":69633,"corporation":false,"usgs":true,"family":"O’Neil","given":"J.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":365395,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70013143,"text":"70013143 - 1984 - Uranium mineralization in response to regional metamorphism at Lilljuthatten, Sweden","interactions":[],"lastModifiedDate":"2024-01-08T23:59:30.282543","indexId":"70013143","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","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":"Uranium mineralization in response to regional metamorphism at Lilljuthatten, Sweden","docAbstract":"Analyses of six mineralized and five nonmineralized whole-rock drill core samples from the uranium deposit at Lilljuthatten yield a lead-lead isochron age of 420 + or - 1 m.y. This age corresponds to the last stage of the Caledonian Orogeny. None of the isotopic systems examined have completely retained the intrusive age of the Olden Granite, but data for several systems suggest an age of approximately 1,650 m.y. Indications that Caledonian hydrothermal activity strongly affected most of the Olden Granite. A model for the genesis of the ore deposit is proposed as follows: (1) derivation of a highly evolved granite by partial melting of crustal materials about 1,650 m.y. ago; (2) pervasive hydrothermal alteration and fracturing of the granite in response to the Caledonian Orogeny approximately 420 m.y. ago; (3) mobilization of uranium and lead in response to circulation of heated fluids; (4) precipitation of these elements in open fractures; and (5) recent modification of the Caledonian uranium distribution as a result of exposure to near-surface conditions.
","language":"English","publisher":"Society of Economic Geologists","doi":"10.2113/gsecongeo.79.3.509","issn":"03610128","usgsCitation":"Stuckless, J., and Troeng, B., 1984, Uranium mineralization in response to regional metamorphism at Lilljuthatten, Sweden: Economic Geology, v. 79, no. 3, p. 509-528, https://doi.org/10.2113/gsecongeo.79.3.509.","productDescription":"20 p.","startPage":"509","endPage":"528","numberOfPages":"20","costCenters":[],"links":[{"id":220516,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"79","issue":"3","noUsgsAuthors":false,"publicationDate":"1984-05-01","publicationStatus":"PW","scienceBaseUri":"505bbdc2e4b08c986b3291e5","contributors":{"authors":[{"text":"Stuckless, J. S.","contributorId":6060,"corporation":false,"usgs":true,"family":"Stuckless","given":"J. S.","affiliations":[],"preferred":false,"id":365392,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Troeng, B.","contributorId":56373,"corporation":false,"usgs":true,"family":"Troeng","given":"B.","email":"","affiliations":[],"preferred":false,"id":365393,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70013142,"text":"70013142 - 1984 - Chromite from the Blue Ridge province of North Carolina","interactions":[],"lastModifiedDate":"2023-02-06T17:24:41.688724","indexId":"70013142","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","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":"Chromite from the Blue Ridge province of North Carolina","docAbstract":"Accessory chromite in dunite shows a variety of textures that indicate alteration. One group, type A, consists of four types of chromite: clean chromite; lattice chromite, in which the invading chlorite occurs along three directions in the (100) plane; optically zoned chromite; and poikiloblastic chromite. Most of type A chromites are surrounded by chromian clinochlore. The other group, type B, consists of euhedral to subhedral chromite grains which are included in olivine or pyroxene. The accessory chromites define a trend exhibited by chromite from other areas that have undergone metamorphism. Olivine-spinel geothermometry indicates equilibration temperatures near 700 degrees C, roughly consistent with mineral assemblages in the host gneisses. Thus, the Blue Ridge dunites are metamorphic rocks and not primary mantle peridotites.
","language":"English","publisher":"American Journal of Science","doi":"10.2475/ajs.284.4-5.507","usgsCitation":"Lipin, B.R., 1984, Chromite from the Blue Ridge province of North Carolina: American Journal of Science, v. 284, no. 4-5, p. 507-529, https://doi.org/10.2475/ajs.284.4-5.507.","productDescription":"23 p.","startPage":"507","endPage":"529","numberOfPages":"23","costCenters":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"links":[{"id":220465,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"North Carolina","otherGeospatial":"Blue Ridge province","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -82.33171420337254,\n 35.16172419965186\n ],\n [\n -80.3549144361715,\n 36.498699563512446\n ],\n [\n -81.74146209797348,\n 36.584654476715144\n ],\n [\n -82.80252728344371,\n 35.94894466653062\n ],\n [\n -84.26280999082724,\n 35.237774229031075\n ],\n [\n -84.35734406944783,\n 35.017268463518306\n ],\n [\n -83.03490976176494,\n 34.9746276516219\n ],\n [\n -82.33171420337254,\n 35.16172419965186\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"284","issue":"4-5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f5e2e4b0c8380cd4c489","contributors":{"authors":[{"text":"Lipin, Bruce R. blipin@usgs.gov","contributorId":5723,"corporation":false,"usgs":true,"family":"Lipin","given":"Bruce","email":"blipin@usgs.gov","middleInitial":"R.","affiliations":[],"preferred":true,"id":365391,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70013141,"text":"70013141 - 1984 - Lu-Hf and Sm-Nd evolution in lunar mare basalts","interactions":[],"lastModifiedDate":"2024-06-28T16:03:03.657239","indexId":"70013141","displayToPublicDate":"1984-01-01T00:00:00","publicationYear":"1984","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":"Lu-Hf and Sm-Nd evolution in lunar mare basalts","docAbstract":"Lu-Hf and Sm-Nd data for mare basalts combined with Rb-Sr and total REE data taken from the literature suggest that the mare basalts were derived by small (≤10%) degrees of partial melting of cumulate sources, but that the magma ocean from which these sources formed was light REE and Hf-enriched. Calculated source compositions range from lherzolite to olivine websterite. Nonmodal melting of small amounts of ilmenite (≤3%) in the sources seems to be required by the Lu/Hf data. A comparison of the Hf and Nd isotopic characteristics between the mare basalts and terrestrial oceanic basalts reveals that the εHf/εNd ratios in low-Ti mare basalts are much higher than in terrestrial oceanic basalts. The results are qualitatively consistent with the hypothesis that terrestrial basalt sources are partial melt residues whereas mare basalt sources are cumulates. Alternatively, the results may imply that the terrestrial mantle has evolved in two (or more) stages of evolution, and that the net effect was depletion of the mantle during the first ∼1–3 b.y. followed by enrichment during the last 1–2 b.y.; or simply that there is a difference in Lu-Hf crystal-liquid partitioning (relative to Sm-Nd between the lunar and terrestrial mantles.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB089iS02p0B459","issn":"00221406","isbn":"0875902332","usgsCitation":"Unruh, D., Stille, P., Patchett, P., and Tatsumoto, M., 1984, Lu-Hf and Sm-Nd evolution in lunar mare basalts: Journal of Geophysical Research Solid Earth, v. 89, no. S02, p. B459-B477, https://doi.org/10.1029/JB089iS02p0B459.","productDescription":"19 p.","startPage":"B459","endPage":"B477","numberOfPages":"19","costCenters":[],"links":[{"id":220464,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"89","issue":"S02","noUsgsAuthors":false,"publicationDate":"2012-09-21","publicationStatus":"PW","scienceBaseUri":"505a4a7fe4b0c8380cd68dfd","contributors":{"authors":[{"text":"Unruh, D.M.","contributorId":8498,"corporation":false,"usgs":true,"family":"Unruh","given":"D.M.","email":"","affiliations":[],"preferred":false,"id":365387,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Stille, P.","contributorId":70113,"corporation":false,"usgs":true,"family":"Stille","given":"P.","email":"","affiliations":[],"preferred":false,"id":365389,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Patchett, P. J.","contributorId":55152,"corporation":false,"usgs":true,"family":"Patchett","given":"P. J.","affiliations":[],"preferred":false,"id":365388,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Tatsumoto, M.","contributorId":76798,"corporation":false,"usgs":true,"family":"Tatsumoto","given":"M.","email":"","affiliations":[],"preferred":false,"id":365390,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ]}