Rescue palaeontology     

Dee Edwards  Dave Williams 《Geology Today》2011,27(2):65-69

A technique for replicating large rock outcrops has been developed so that casts of these surfaces can be archived in their present stage of preservation. Researchers can then study these casts in the laboratory under optimum lighting conditions, sometimes revealing new fossil evidence, while students and members of the public can be shown geological features that might otherwise be inaccessible to them.  相似文献   

Two Dimensional Wavelet Analysis Applied to Geoid Anomalies Mixing and High Rayleigh Number Mantle Convection     

Luke Vecsey  Cathy Hier  Dave Yuen  Erik Sevre 《Visual Geosciences》2001,6(3):1-6

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Fitness spaces and their potential for visualizing change in the physical landscape     

Rob Inkpen  & Dave Petley 《Area》2001,33(3):242-251

The use of the metaphors of general fitness and N-K spaces can assist in the understanding of the development of the physical landscape. Different modes of change can be viewed as different types of movement in, and distortions of, these phase spaces. Visualized in this manner landscape change can be viewed as both channelized, constrained and random.  相似文献   

A geochemical model of mid-ocean ridge magma chambers     

Dave Robson  J.R. Cann 《Earth and Planetary Science Letters》1982,60(1):93-104

A computer model of mid-ocean ridge basalt generation using trace element geochemistry has been developed. The model simulates a periodically replenished, continually cooled and fractionated magma chamber, with periodic lava extrusion. Primitive basalts from the ocean floor are used to generate likely evolution paths for the magma chamber. The steady state variant of this model has led to the isolation of several variables which critically affect the basalt composition. Although the fraction of cumulates is an important parameter, other variables such as the volume of incoming magma batches, their frequency, and the volume of the mixing cell, play a critical part especially on slow-spreading ridges. The growing magma chamber model uses random number generators to simulate the initiation and growth of a chamber. This model predicts a rapid increase in incompatible element concentrations, immediately after chamber initiation on a fast-spreading ridge. This would occur in situations such as propagating rifts and may help in the understanding of ferrobasalt generation.  相似文献   

Water and Radioactive Tracer Flow in a Heterogeneous Field-Scale System   总被引：1，自引：0，他引：1  

Frank M. Dunnivant  Meredith E. Newman  Carolyn W. Bishop  Dave Burgess  John R. Giles  Brian D. Higgs  Joel M. Hubbell  Erick Neher  Greg T. Norrell  M. Cathy Pfiefer  Indrek Porro  Robert C. Starr  Allan H. Wylie 《Ground water》1998,36(6):949-958

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Cation ordering in omphacite and effect on deformation mechanism and lattice preferred orientation (LPO)   总被引：1，自引：0，他引：1  

Frank E. Brenker  Dave J. Prior  Wolfgang Friedrich Müller 《Journal of Structural Geology》2002,24(12)

We present microstructural data and lattice preferred orientations (LPOs) of omphacites from a suite of eclogites, from the Adula/Cima Lunga nappe (Central Alps). Our work shows a surprisingly strong correlation between the measured LPO and the ordering state of cations in omphacite. Estimates of deformation temperature from metamorphic petrology, together with measured omphacite compositions and LPOs, determine the field (ordering state), on the omphacite phase diagram, into which each sample falls. LPOs dominated by L-type and S-type signatures are developed in samples that fall in the P2/n field (ordered structure) and C2/c field (disordered structure), respectively.Dislocations with b=1/2−110 or b=[001] are observed in the transmission electron microscope (TEM) in all samples. The former change from a perfect dislocation in the C2/c structure to a partial in P2/n. Any movement of a partial dislocation requires the formation or growth of a stacking fault. Furthermore, in order to pass an obstacle a partial dislocation has to constrict to a unit dislocation. The energy to form a constriction is high in omphacite due to the large separation width. Thus, the activity of the b=1/2−110 dislocation is hindered in the P2/n structure relative to the C2/c structure, which change the balance between the two and might give rise to the different LPOs.  相似文献   

Shipboard sunphotometer measurements of aerosol optical depth spectra and columnar water vapor during ACE‐2, and comparison with selected land, ship, aircraft, and satellite measurements     

John M. Livingston  Vladimir N. Kapustin  Beat Schmid  Philip B. Russell  Patricia K. Quinn  Timothy S. Bates  Philip A. Durkee  Peter J. Smith  Volker Freudenthaler  Matthias Wiegner  Dave S. Covert  Santiago Gassó  Dean Hegg  Donald R. Collins  Richard C. Flagan  John H. Seinfeld  Vito Vitale  Claudio Tomasi 《Tellus. Series B, Chemical and physical meteorology》2000,52(2):594-619

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The Geomagnetic Spectrum For 1980 and Core-Crustal Separation     

Joseph C. Cain  Zhigang Wang  Dave R. Schmitz  J. Meyer§ 《Geophysical Journal International》1989,97(3):443-447

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Bianchi Type-III String Cosmological Model with Bulk Viscous Fluid in General Relativity     

Raj Bali  Shuchi Dave 《Astrophysics and Space Science》2002,282(2):461-466

A Bianchi type-III string cosmological model with bulk viscous fluid for massive string is investigated. To get a determinate solution, a supplementary condition B=C ⁿ, between metric potentials, is used whereB and C are function of time alone. The behaviour of the model in presence and absence of bulk viscosity, is discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

A multiply imaged, submillimetre-selected ultraluminous infrared galaxy in a galaxy group at z∼ 2.5     

Jean-Paul Kneib  Paul P. van der Werf  Kirsten Kraiberg Knudsen  Ian Smail  rew Blain  Dave Frayer  Vicki Barnard  Rob Ivison 《Monthly notices of the Royal Astronomical Society》2004,349(4):1211-1217

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