Early mining in South Australia     

PETER J. SMITH 《Geology Today》1988,4(1):30-34

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Concentrations of B,Sm, Gd and H in 24 Reference Materials*     

Denis M. SHAW  Patti L.C. SMITH 《Geostandards and Geoanalytical Research》1991,15(1):59-66

Analysis of 24 reference materials for B, Sm, Gd, H, has been carried out over several years, using prompt gamma neutron activation analysis. The results are compared with values obtained by other workers, in order to better calibrate these standards. In most cases our results of repeated analysis of RMs show agreement with results from other laboratories, using various methods. A djustments to working values are proposed in some cases.  相似文献   

Basalt and Sediment Geochemistry and Magma Petrogenesis in a Transect from Oceanic Island Arc to Rifted Continental Margin Arc: the Kermadec--Hikurangi Margin, SW Pacific   总被引：2，自引：1，他引：1  

GAMBLE  JOHN; WOODHEAD  JON; WRIGHT  IAN; SMITH  IAN 《Journal of Petrology》1996,37(6):1523-1546

Sediment mixing and recycling through a subduction zone canbe detected in lead isotopes and trace elements from basaltsand sediments from the Kermadec-Hikurangi Margin volcanic arcsystem and their coupled back-arc basins. Sr, Nd and Pb isotopesfrom the basalts delineate relatively simple, almost overlapping,arrays between back-arc basin basalts of the Havre Trough-NgatoroBasin (⁸⁷Sr/⁸⁶Sr = 0.70255; _Nd=+9.3; ²⁰⁶Pb/²⁰⁴Pb = 18.52; ²⁰⁸Pb/²⁰⁴Pb= 38.18), island arc basalts from the Kermadec Arc togetherwith basalts from Taupo Volcanic Zone (⁸⁷Sr/⁸⁶Sr 0.7042; _Nd= +5; ²⁰⁶Pb/²⁰⁴Pb= 18.81; ²⁰⁸Pb/²⁰⁴Pb = 38.61), and sedimentsderived from New Zealand's Mesozoic (Torlesse) basement (⁸⁷Sr/⁸⁶Sr 0.715; _Nd —4; ²⁰⁶Pb/²⁰⁴Pb 18.86; ²⁰⁸Pb/²⁰⁴Pb 38.8).Basalts from the arc front volcanoes have high Cs, Rb, Ba, Th,U and K, and generally high but variable Ba/La, Ba/Nb ratios,characteristic of subduction-related magmas, relative to typicaloceanic basalts. These signatures are diluted in the back-arcbasins, which are more like mid-ocean ridge basalts. Strongchemical correlations in plots of SiO₂ vs CaO and loss on ignitionfor the sediments (finegrained muds) are consistent with mixingbetween detrital and biogenic (carbonate-rich) components. Otherdata, such as Zr vs CaO, are consistent with the detrital componentcomprising a mixture of arc- and continent-derived fractions.In chondrite-normalized diagrams, most of the sediments havelight rare earth element enriched patterns, and all have negativeEu anomalies. The multielement diagrams have negative spikesat Nb, P and Ti and distinctive enrichments in the large ionlithophile elements and Pb relative to mantle. Isotopic measurementsof Pb, Sr and Nd reveal restricted fields of Pb isotopes butwide variation in Nd and Sr relative to other sediments fromthe Pacific Basin. Rare K-rich basalts from Clark Volcano towardthe southern end of the oceanic Kermadec Island Arc show unusualand primitive characteristics ( 2% K₂O at 50% SiO₂, Ba 600p.p.m., 9–10% MgO and Ni > 100 p.p.m.) but have highlyradiogenic Sr, Nd and Pb isotopes, similar to those of basaltsfrom the continental Taupo Volcanic Zone. These oceanic islandarc basalts cannot have inherited their isotope signatures throughcrustal contamination or assimilation—fractional crystallizationtype processes, and this leads us to conclude that source processesvia bulk sediment mixing, fluid and/or melt transfer or somecombination of these are responsible. Although our results showclear chemical gradients from oceanic island arc to continentalmargin arc settings (Kermadec Arc to Taupo Volcanic Zone), overlapbetween the data from the oceanic and continental sectors suggeststhat the lithospheric (crustal contamination) effect may beminimal relative to that of sediment subduction. Indeed, itis possible to account for the chemical changes by a decreasenorthward in the sediment flux into the zone of magma genesis.This model receives support from recent sediment dispersal studiesin the Southern Ocean which indicate that a strong bottom current(Deep Western Boundary Current) flows northward along the easterncontinental margin of New Zealand and sweeps continental derivedsediment into the sediment-starved oceanic trench system. Thetrace element and isotopic signatures of the continental derivedcomponent of this sediment are readily distinguished, but alsodiluted in a south to north direction along the plate boundary. KEY WORDS: subduction zone basalts; sediments; Sr-, Nd-, Pb-isotopes; trace elements ^*Present address: School of Earth Sciences, University of Melbourne, Parkville, Vic. 3052, Australia.  相似文献   

Pyrometamorphism of Phyllites by a Dolerite Plug     

SMITH  D. G. W. 《Journal of Petrology》1969,10(1):20-55

The progressive thermal metamorphism of Dalradian phyllitesadjacent to a Tertiary basic plug is traced petrographicallyfrom the initial stages of breakdown of micaceous minerals tothe eventual development, in places near the contact, of rheomorphicmaterial of granitic composition and complementary highly desilicatedferromagnesian residues. Chemical analyses of unmetamorphosedand thermally metamorphosed country rock, granophyres, and desilicatedresidues, are used to illustrate the chemistry of these metamorphicprocesses and to suggest approximate temperature-pressure conditionsunder which they took place. The petrological significance ofthe emery-like residues is discussed briefly.  相似文献   

IDENTIFICATION OF SEA-FLOOR SEDIMENTS USING UNDERWAY ACOUSTICS*     

W. N. LI  D. TAYLOR SMITH 《Geophysical Prospecting》1969,17(3):231-247

Laboratory measurements, and a few in situ observations, show that saturated marine sediments have interdependent mechanical and acoustical properties, Acoustically, of particular importance are the acoustic impedance, velocity of sound and the sound attenuation coefficient of the sediment. The first two properties can be measured relatively easily from a surface ship; the measurement of attenuation however, is more problematical. It is suggested that this can be achieved by a quantitative treatment of the acoustic data collected during routine sub-bottom profiling over a variable thickness of superficial sediments. In the assessment of four different sediment locations in the Irish Sea it was found that quantitative treatment of the acoustic signals yielded both a value of the attenuation coefficient as well as a measure of the frequency dependence of the attenuation. In addition a statistical analysis of the signal intensities seems to provide an indication of the relative roughness of the bottom and sub-bottom interfaces. From the wide range of information provided the mechanical properties of the sea-floor sediment may be estimated.  相似文献   

New Lateglacial fauna and early Mesolithic human remains from northern England     

IAN R. SMITH  DAVID M. WILKINSON  HANNAH J. O'REGAN 《第四纪科学杂志》2013,28(6):542-544

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RESEARCH IN CUBA: NAVIGATING LOGISTICAL BARRIERS*     

JEFFREY S. SMITH  CHARLES O. COLLINS  JENNY PETTIT 《Geographical review》2012,102(3):382-389

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The Meteoritical Bulletin,No. 98, September 2010     

Michael K. WEISBERG  Caroline SMITH  Christopher HERD  Henning HAACK  Akira YAMAGUCHI  Hasnaa CHENNAOUI AOUDJEHANE  Linda WELZENBACH  Jeffrey N. GROSSMAN 《Meteoritics & planetary science》2010,45(9):1530-1551

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The Meteoritical Bulletin,No. 97     

Michael K. WEISBERG  Caroline SMITH  Gretchen BENEDIX  Christopher D. K. HERD  Kevin RIGHTER  Henning HAACK  Akira YAMAGUCHI  Hasnaa CHENNAOUI AOUDJEHANE  Jeffrey N. GROSSMAN 《Meteoritics & planetary science》2010,45(3):449-493

Abstract– In this edition of The Meteoritical Bulletin, a total of 506 newly approved meteorite names with their relevant data are reported. These include 354 from northwest Africa, 31 from the Americas, 15 from Antarctica (Koreamet), 85 from Asia, 20 from Australia, and 1 from Europe. Among these meteorites are 2 falls, Grimsby (Canada) and Santa Lucia (2008) (Argentina). Also described are a CM with low degree of alteration, new ungrouped chondrites and achondrites, and 4 Martian meteorites.  相似文献   

Carbon monoxide production and emission by some Scottish soils   总被引：1，自引：0，他引：1  

J. M. MOXLEY  K. A. SMITH 《Tellus. Series B, Chemical and physical meteorology》1998,50(2):151-162

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