Mineralogy,petrology, and chemistry of a Luna 16 basaltic fragment,sample B-1     

A.L. AlbeeA.A. Chodos  A.J. GancarzE.L. Haines  D.A. PapanastassiouL. Ray  F. TeraG.J. Wasserburg  T. Wen 《Earth and Planetary Science Letters》1972

Luna 16 sample B-1 was the largest fragment (62 mg) obtained in the sample exchange with the USSR. Petrologic, mineralogic, and chemical investigations have been made on this fragment in conjunction with Rb-Sr and⁴⁰Ar/³⁹Ar investigations by our colleagues. Sample B-1 is a fine-grained ophitic basalt but is distinguished from the Apollo samples by containing a single pyroxene, predominantly pigeonitic, an ilmenite content (7%) intermediate to that of the Apollo 11 and 12 samples, and subequal amounts of pyroxene (50%) and plagioclase (40%). Chemically it is distinguished by a high Sr content (437 ppm) and a high K/U value (4700). The K-content (1396 ppm) is higher than that of Luna 16 soil sample A-2.  相似文献   

P total,P_{H_2 O} and the occurrence of cummingtonite in volcanic rocks     

B. J. Wood  I. S. E. Carmichael 《Contributions to Mineralogy and Petrology》1973,40(2):149-158

The phenocryst assemblage of cummingtonite, orthopyroxene, quartz, titanomagnetite and ilmenite in rhyolites of New Zealand has been used to calculate P _total and . The values of P _total and depend strongly upon whether an ideal mixing, or an ordered, model is used for the solid-solutions, but in both cases P _total.The rhyolite magma contained over 9 per cent water (by weight) when the cummingtonite phenocrysts precipitated, and possibly as much as 12 per cent, so that it is surprising that one of these rhyolites is a coherent lava. The calculated values of P _total and are very sensitive to uncertainty in both the composition of the solid-solutions and temperature. Calculations show that >0.7–0.8 P _total for cummingtonite to precipitate in rhyolites, and that iron-rich olivine and cummingtonite could only exist in rhyolites over a small temperature range at a pressure near 5 kilobars. Hornblende phenocrysts co-existing with fayalitic olivine in rhyolites accordingly have a very low activity of Mg₇Si₈O₂₂(OH)₂.  相似文献   

Toxins in the red Whelk     

P.A. Ayres  P.C. Wood 《Marine pollution bulletin》1973,4(10):157-159

A case of poisoning following consumption of Neptunea occurred in Scotland in 1970. The organism is caught in traps with the Edible Whelk where it constitutes less than 0·5% of the catch. Toxin in the salivary gland demonstrated by mouse bioassay could be distinguished from PSP toxin. It is concluded that the public health risk from consumption of the Edible Whelk is negligible.  相似文献   

The economic analysis of raft foundations     

L. A. Wood 《国际地质力学数值与分析法杂志》1977,1(4):397-405

An approximate method, using a simplified soil model, for predicting the behaviour of raft foundations subjected to applied vertical forces and moments will be outlined. Results obtained for circular rafts of finite rigidity are compared with those obtained, from more rigorous solutions, by other authors. Satisfactory agreement is obtained for the surface settlements and raft bending moments over a wide range of soil inhomogeneity. Finally, the versatility of the method of analysis is illustrated for an unusual asymmetrical structure. Computed total and differential settlements are shown to be in reasonable agreement with measured values and those predicted by an independent plane strain finite element analysis.  相似文献   

The effect of H₂O on crystal-melt partitioning of trace elements     

Bernard J Wood  Jonathan D Blundy 《Geochimica et cosmochimica acta》2002,66(20):3647-3656

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Mapping of fault rupture of the 28 may 2004 iran earthquake (mw= 6.2) using satellite image     

M. Sharifikia  C. S. Dubey  B. K. Sharma  M. Chaudhry  P. K. Champati Ray 《Journal of the Indian Society of Remote Sensing》2006,34(4):423-430

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The Apoteri volcanic formation — tholeiitic flows in the North Savannas Graben of Guyana and Brazil     

Jevan P. Berrangé  Ray Dearnley 《International Journal of Earth Sciences》1975,64(1):883-899

Amygdaloidal tholeiitic flows, locally pillowed, have been mapped at intervals over a distance of 280 km along the margins of the North Savannas Rift Valley in southern Guyana and Brazil. The combined chemical and petrological evidence suggests that the formation represents an originally uniform continental tholeiitic sequence that has undergone variable secondary alteration involving increasing oxidation and ingress of soda, potash and water. The lavas are both spatially and temporally related to the rift faulting; field observations and K∶Ar age determinations on eleven samples from different localities indicate that the flows were erupted during the Early to Middle Jurassic (180-150 m. y.). It is shown that this tectono-magmatic event is synchronous with the initiation of the southern North Atlantic rift and the pan-Antarctic rift which resulted in fragmentation of the continents according to the scheme ofDietz &Holden (1970).  相似文献   

DR TERRANCE CHARLES RICHARDS     

John E. R. Wood 《Geophysical Prospecting》1980,28(2):314-315

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The Claygate Beds of Essex     

C.R. Bristow  R.A. Ellison  C.J. Wood 《Proceedings of the Geologists' Association. Geologists' Association》1980,91(4):261-277

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The interstellar dust as a precursor of Ca,Al-rich inclusions in carbonaceous chondrites     

John A. Wood 《Earth and Planetary Science Letters》1981

(1) The observed anomalies in meteoritic oxygen isotope compositions are not due to an incomplete mixing of several dust or gas-plus-dust components in the solar nebula. If they were, other elements would display similar anomalies. (The FUN inclusions in Allende appear to be exceptions to this premise.) (2) The anomalies must therefore stem from differing degrees of incomplete exchange of oxygen isotopes between the primordial gas and dust components of the nebula. The dust is more likely to have been the¹⁶O-enriched component. (3) Since the isotopic difference between dust and gas probably could not have been preserved if the dust was ever completely vaporized in the nebula, the Ca,Al-rich inclusions (CAI's) in carbonaceous chondrites are unlikely to be condensates, but instead are distillation residues. (4) If so, the observed depletion of super-refractory elements in the Group II CAI's cannot have been accomplished by fractional condensation in the solar nebula. (5) Then this depletion, and a number of other properties of the components of primitive meteoritic material, must be relics of pre-solar system fractionations among different populations of interstellar dust grains.  相似文献