The pulse-probe method of conductivity measurement   总被引：11，自引：0，他引：11  

C. R. B. Lister 《Geophysical Journal International》1979,57(2):451-461

Summary. An alternative to the steady heating of a cylindrical probe, in the 'needle-probe' method of conductivity measurement, is the observation of the thermal decay from a short, calibrated, heat pulse. The theoretical solution is the time-differential of that for the former method, and requires only the measurement of point temperatures rather than the determination of a gradient. A careful analysis of the theoretical decay function shows that it should be possible to make accurate conductivity measurements in as little as three probe 'time constants' if external information is available on the heat capacity of the medium. A self-contained method, using two temperature determinations from a record about six time-constants long, can be used where such information is not available. The theory was tested by measurements on the ocean-floor, and the data correspond to the theory when a correction was applied for some internal probe conduction problems.  相似文献   

Heat flow maintained in ocean basins of great age: investigations in the north-equatorial West Pacific   总被引：5，自引：0，他引：5  

C. R. B. Lister  J. G. Sclater  E. E. Davis  H. Villinger  S. Nagihara 《Geophysical Journal International》1990,102(3):603-628

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Fabric transitions in the Saxony granulite terrain     

G.S Lister  U.F Dornsiepen 《Journal of Structural Geology》1982,4(1):81-92

Quartz fabric transitions reported from the Saxony granulite terrain and from the nearby Ore Mountains are interesting because of the changes in the pattern types, and the variation in the opening angles of the fabric skeletons. A short summary is presented of salient features in research documented in the East German literature between 1961 and 1978.The changes in fabric skeleton with decreasing metamorphic grade are proposed as mainly consequent to the deactivation of prism 〈c〉 glide systems as temperature decreases. Fabrics indicative of the appearance of the 〈c〉 Burgers vector might be diagnostic for deformation in regimes of comparatively high temperatures or low strainrates, or for deformation, under conditions such that there is a relatively high ‘kinetically effective’ hydroxyl content in the quartz structure.  相似文献   

The effect of the basal-prism mechanism switch on fabric development during plastic deformation of quartzite     

G.S Lister 《Journal of Structural Geology》1981,3(1):67-75

Blacic described a transition from basal 〈a〉 to prism 〈c〉 dislocation glide systems as temperature increased or strain-rate decreased in sequences of experiments involving deformation of single crystals of quartz. In this paper theoretical aspects of competition between these systems during plastic deformation are discussed. It is concluded that the basal-prism mechanism switch should have important consequences for the development of crystallographic fabrics during plastic deformation of quartzite, and the Taylor-Bishop-Hill analysis is used in an attempt to predict expected fabric transitions.  相似文献   

The American public’s preference for preparation for the possible effects of global warming: impact of communication strategies     

Bo MacInnis  Jon A. Krosnick  Adina Abeles  Margaret R. Caldwell  Erin Prahler  Debbie Drake Dunne 《Climatic change》2015,128(1-2):17-33

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Flow localization in fissure eruptions     

Jonathan J. Wylie  Karl R. Helfrich  Brian Dade  John R. Lister  John F. Salzig 《Bulletin of Volcanology》1999,60(6):432-440

 During a basaltic fissure eruption heat transfer from the hot magma to the surrounding rock causes a dramatic increase in the magmatic viscosity and solidification at the margins. Both viscosity contrast and solidification can amplify initial variations in the flow rate and lead to localization of the flow along the strike of the fissure. However, for typical parameters, amplification driven by solidification is slower and significantly weaker than amplification driven by viscosity variations. In fact, for the parameters examined, the amplification due to solidification is so weak that its effect is almost insignificant, whereas viscosity variation provides a strong active mechanism for flow localization. Laboratory experiments illustrate viscous localization and suggest that this mechanism is robust. The dependence of viscosity on temperature can cause a small change in the pressure of the magma chamber to lead to a large jump in the flow rate of magma through the fissure. Received: 13 March 1998 / Accepted: 27 September 1998  相似文献