Electron spin resonance of auriferous and barren quartz at beaconsfield, Northern Tasmania   总被引：1，自引：0，他引：1  

J. C. Van Moort  D. W. Russell 《Journal of Geochemical Exploration》1987,27(3)

The intensity of ESR spectra of powdered quartz from auriferous veins at Beaconfield is greater that the intensity of the spectra from barren vein quartz at the same locality. Lattice impurities are presumed to be the cause of the electron paramagnetism of the mineralised quartz species. The method can be used for the characterisation of different types of quartz and may provide a tool useful in exploration geochemistry.  相似文献   

A stable isotope study of serpentinization and metamorphism in the Highland Border Suite,Scotland, U.K.     

Nicholas P Ikin  Russell S Harmon 《Geochimica et cosmochimica acta》1983,47(2):153-167

$\text{D}\text{H}$ and ${}^{18}\text{O}{}^{16}\text{O}$ ratios have been measured for whole-rock samples and mineral separates from the mafic and ultramatic rocks of the Cambro-Ordovician Highland Border Suite. The H- and O- isotopic compositions of these rocks record individual stages in a relatively complex 500 Myr old hydrothermal/metamorphic history. Lizardite serpentinites (δD ～ ? 105‰; δ¹⁸O ～ + 6.2‰) record a premetamorphic history and indicate that parent harzburgites, dunites, and pyroxenites were serpentinized through low-temperature interaction with meteoric waters during cooling. The other rocks of the Highland Border Suite record subsequent interaction with metamorphic fluids. Amphibolite facies hornblende schists were produced through thrust-related (dynamothermal) metamorphism of spilitic pillow lavas. During dehydration, D-enriched fluids were driven off from the spilites thus leaving the hornblende schists to equilibrate with a relatively D-depleted internal fluid reservoir (δD ～ ? 45‰). The expelled D-enriched fluids may have mixed with more typical Dalradian metamorphic waters which then exchanged with the remaining mafic rocks and lizardite serpentinites during greenschist facies regional metamorphism to produce antigorite serpentinites (δD ～ ? 62‰; δ¹⁸O ～ + 8‰) and greenschist metaspilites (δD ～ ? 57‰; δ¹⁸O ～ + 7.3‰) with similar H- and O-isotopic compositions. Serpentinites which have been only partially metamorphosed show intermediate H-isotopic compositions between that of metamorphic antigorite (δD ～ ? 62‰) and non-metamorphic lizardite δD ～ ? 105‰) end members.  相似文献   

Major element chemistry of glasses in Apollo 14 soil 14156     

Arch M. Reid  W.I. Ridley  Russell S. Harmon  Pete Jakes̆ 《Geochimica et cosmochimica acta》1973,37(3):695-699

Glasses in a soil sample (14156) from the middle layer of the trench at the Fra Mauro landing site show a wide range of compositions clustered around certain preferred compositions. Ninety per cent of the glasses are of two major types—Fra Mauro basalt (63 per cent) with high K and 17 weight per cent Al₂O₃ and Highland basalt or anorthositic gabbro (27 per cent) with low K and 25–26 weight per cent Al₂O₃. The glass population is almost identical with that of the comprehensive soil 14259 (Apollo Soil Survey, 1971).  相似文献   

Annual oceanic heat transports computed from an atmospheric model     

James R. Miller  Gary L. Russell  Lie-Ching Tsang 《Dynamics of Atmospheres and Oceans》1983,7(2):95-109

Mean annual estimates of the oceanic poleward energy transport are obtained using a global atmospheric general circulation model. The computations are carried out by using the atmospheric model to determine the net annual heat flux into the ocean on an 8° × 10° grid. Assuming no net annual heat storage, the annual surface heat fluxes into any zonal band must be accompanied by a corresponding meridional heat transport in the ocean. Heat is transported northward at all latitudes in the Atlantic Ocean and is transported poleward in both hemispheres in the Pacific Ocean. To account for the net northward transport throughout the Atlantic, heat is transported into the Atlantic from the Indian and Pacific basins. The results are compared with several recent direct and indirect calculations of oceanic meridional heat transports.  相似文献   

Reply to Rasool     

J. Hansen  D. Johnson  A. Lacis  S. Lebedeff  P. Lee  D. Rind  G. Russell 《Climatic change》1983,5(2):203-204

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Hydrothermal pyrite chimneys from the Ballynoe baryte deposit,Silvermines, County Tipperary,Ireland   总被引：4，自引：0，他引：4  

R. C. L. Larter  A. J. Boyce  M. J. Russell 《Mineralium Deposita》1981,16(2):309-317

We report the discovery of pyrite tubes 0.1 to 20mm in diameter in the Ballynoe sedimentary baryte deposit. Well developed tubes comprise concentric layers of pyrite of contrasting crystal sizes 0.05 to 1 mm thick. An outer rim of crystalline baryte 10mm thick commonly coats the tubes where these are not touching. The central canals contain myriad pyrite framboids. These tubes have characteristics in common with the chimney spires found on the East Pacific Rise at 21°N from which metal bearing solutions issue at temperatures of up to 380±30°C. Their presence carries the implication that the baryte deposit was not a distal facies of the Silvermines sedimentary pyritic zinc and lead ore, but was produced from local hydrothermal exhalations, though in a shallower part of the basin than the coeval sulphide deposits which had their own feeders. Some epigenetic mineralization may be awaiting discovery beneath the feeder sites at Ballynoe.  相似文献   

Structural analysis of sheath folds with horizontal X-axes,northeast Canada     

John Russell Henderson 《Journal of Structural Geology》1981,3(3):203-210

Early Proterozoic supracrustal rocks occur below a thick nappe of Archaean basement gneiss in the Melville Peninsula where sheath folds are exposed in a wide zone of middle Proterozoic dynamothermal metamorphism. Outcrop patterns of truncated isoclinal sheath folds resemble cylindrical folds except in relatively small areas around the paraboloidal caps. Bulk extension axes are parallel to strike in the belt as shown by isoclinal sheath folds with horizontal central axes (X-axes), as well as similarly aligned mullion structure and rotated scapolite prisms. Extension axes converge from northeast to southwest in the apparent flow direction.  相似文献   

Advances in research and forecasting of tropical cyclones from 1963–2013     

Russell L. Elsberry 《Asia-Pacific Journal of Atmospheric Sciences》2014,50(1):3-16

A review of progress over the past 50 years in observing and forecasting of tropical cyclones is presented. Tremendous progress has been made in track forecasting in the past 20 years with the improvement in numerical model guidance and the use of consensus forecasting, and this has contributed to a number of warning centers now issuing five-day track forecasts that are as accurate as three-day forecasts of a decade ago. Techniques are now available to specify the track forecast uncertainty for assessing the risk of a tropical cyclone. With the advent of five-day forecasts, a focus on improved understanding of formation has led to two field experiments. A recent advance has been in extended-range (5–30 days) forecasts of tropical cyclone events (formations and tracks) in the western North Pacific from the ECMWF 32-day ensemble predictions. This advance is a contribution to a goal of seamless forecasting from one day to a season for tropical cyclones. Little progress has been made in intensity forecasting, although the Hurricane Forecast Improvement Project in the United States and recent field experiments may offer some future advances. Some advances in forecasting tropical cyclone impacts such as storm surge, surface waves, and precipitation have been achieved. Future opportunities for continued advances are possible such that improved warnings can lead to reductions in losses of lives and minimizing damages from tropical cyclones.  相似文献   

Climate change impacts on freshwater fish,coral reefs,and related ecosystem services in the United States     

Diana Lane  Russell Jones  David Mills  Cameron Wobus  Richard C. Ready  Robert W. Buddemeier  Eric English  Jeremy Martinich  Kate Shouse  Heather Hosterman 《Climatic change》2015,131(1):143-157

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Erratum to: Climate change impacts on freshwater fish,coral reefs,and related ecosystem services in the United States     

Diana Lane  Russell Jones  David Mills  Cameron Wobus  Richard C. Ready  Robert W. Buddemeier  Eric English  Jeremy Martinich  Kate Shouse  Heather Hosterman 《Climatic change》2015,131(1):159-161

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