Thermal metamorphism of primitive meteorites—VIII. Noble gases,carbon and sulfur in Allende (C3) meteorite heated at 400–1000°C     

Gregory F. Herzog  Everett K. Gibson  Michael E. Lipschutz 《Geochimica et cosmochimica acta》1979,43(3):395-404

Noble gases, C and S are lost from Allende samples heated for 1 week at temperatures of 400–1000°C in a low pressure environment. In the extreme, losses of ³He and ⁴He are ~ 100 × while for C. S and Ne, Ar and Kr isotopes and ¹³²Xe. these are ≤10 ×. Except for He, these losses are less severe than those of Bi or Tl from samples heated in the same runs. Significant He. Ne and Ar isotopic fractionation during heating indicates preferential outgassing of specific reservoirs. Apparent activation energies for all species generally indicate loss controlled by a diffusive process. Next to He, ⁴⁰Ar is the most labile of those species considered here but still less so than Bi or Tl. L-group (but not H- or LL-group) chondrites may have lost mobile elements like Tl while being outgassed after late impact-associated heating. A less likely alternative possibility involving a collateral relation between condensation conditions and depth in a parent object may also explain the L-group trend.  相似文献   

Stratified flow over non-uniform surface conditions: Mixing-length model     

Chin-Hua Huang  Everett C. Nickerson 《Boundary-Layer Meteorology》1974,5(4):395-417

The response of a neutrally stratified atmospheric surface layer to sudden changes in surface roughness and temperature is investigated by solving the steady-state boundary-layer equations. Near the discontinuities, the distributions of velocity and shear stress are found to be critically dependent upon whether or not the pressure and buoyancy terms are retained in the governing equations. Computed distributions of velocity and shear stress are found to be in good agreement with windtunnel and field data. The growth of the internal boundary layer under neutral conditions for smooth to rough transitions follows the 0.8 power law; however, rough to smooth transitions are associated with a 0.7 power law.  相似文献   

Constraints and Categories of Vadose Zone Monitoring Devices     

Lorne G. Everett  Edward W. Hoylman  L. Graham Wilson  Leslie G. McMillion 《Ground Water Monitoring & Remediation》1984,4(1):26-32

Traditional monitoring methods using chemical analysis of ground water samples to detect pollutant migration are being superseded or used in conjunction with innovative approaches. A need to detect pollutants before they reach the water table has drawn interest to vadose (unsaturated) zone monitoring and brought together hydrogeologists, soil scientists and agricultural engineers who have been working on this subject for years.
Recent studies have identified over 50 different types of vadose zone monitoring devices and methods that have optimum utility in varying hydrogeologic settings. In general, measurements made in the vadose zone are trying to define storage, transmission of liquid waste in terms of flux and velocity, and pollutant mobility.
Criteria for the selection of alternative vadose zone monitoring methods are important for the development of site-specific systems. These criteria include: type of site; applicability to new, active, and abandoned sites; power requirements; depth limitations; multiple use capability; type of data collection system; reliability and life expectancy; degree of operational complexity; direct versus indirect methods; applicability to alternate media; effect on flow regime; and effect of hazardous waste on sampling or measurements. Application of the selection criteria is discussed in Everett et al. (1982a).  相似文献   

Comment on “Late Holocene Lake Sedimentology and Climate Change in Southern Alberta, Canada” by Campbell     

Everett M. White 《Quaternary Research》2002,58(3)

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Non-linear inversion of controlled source multi-receiver electromagnetic induction data for unexploded ordnance using a continuation method   总被引：1，自引：0，他引：1  

A. Benavides  M.E. Everett   《Journal of Applied Geophysics》2007,61(3-4):243-253

This work adopts a continuation approach, based on path tracking in model space, to solve the non-linear least-squares problem for discrimination of unexploded ordnance (UXO) using multi-receiver electromagnetic induction (EMI) data. The forward model corresponds to a stretched-exponential decay of eddy currents induced in a magnetic spheroid. We formulate an over-determined, or under-parameterized, inverse problem. An example using synthetic multi-receiver EMI responses illustrates the efficiency of the method. The fast inversion of actual field multi-receiver EMI responses of inert, buried ordnances is also shown. Software based on the continuation method could be installed within a multi-receiver EMI sensor and used for near-real-time UXO decision-making purposes without the need for a highly-trained operator.  相似文献   

Distribution, ,movement,and evolution of the volatile elements in the lunar regolith     

Everett K. Gibson Jr. 《Earth, Moon, and Planets》1975,13(1-3):321-326

The abundances and distributions of carbon, nitrogen, and sulfur in lunar soils are reviewed. Carbon and nitrogen have a predominantly extra-lunar origin in lunar soils and breccias, while sulfur is mostly indigeneous to the Moon. The lunar processes which effect the movement, distribution, and evolution of carbon, nitrogen, and sulfur, along with the volatile alkali elements sodium, potassium, and rubidium during regolith processes are discussed. Possible mechanisms which may result in the addition to or loss from the Moon of these volatile elements are considered.  相似文献   

Theoretical controlled-source electromagnetic responses of fast-spreading mid-ocean ridge models     

M. E. Everett  R. N. Edwards 《Geophysical Journal International》1991,105(2):313-323

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Coupled organic synthesis and mineral alteration on meteorite parent bodies     

Mitch SCHULTE  Everett SHOCK 《Meteoritics & planetary science》2004,39(9):1577-1590

Abstract— The hypothesis that the soluble fraction of the organic compounds present in carbonaceous chondrite meteorites was formed during aqueous alteration of the parent body was tested with mass‐transfer, reaction‐path calculations. In these calculations, we start with likely compositions of the original parent body and asteroidal fluids that are far from thermodynamic equilibrium, and metastable and stable equilibrium constraints are imposed as the total Gibbs free energy of the parent body environment is minimized. The results of these calculations suggest that the classes of soluble organic compounds present in carbonaceous chondrite meteorites could have formed during relatively low temperature aqueous alteration of the meteorite parent body or bodies. The main controls on the potential for synthesis and transformation of organic compounds were the oxidation state of the rock/fluid system, the bulk composition of that system, and the temperatures that were achieved during the alteration event or events. It also appears that the alteration mineral assemblages were influenced by the presence of soluble organic compounds and reaction among them.  相似文献   

Igor S. Zektser,multifaceted Russian hydrogeologist     

Zaltsberg  Ernst  Vartanyan  Genrikh  Everett  Lorne 《Hydrogeology Journal》2017,25(3):863-866

Hydrogeology Journal -  相似文献   

Anomalous Magnetic Variations in Southwestern Scotland     

J. E. A. Osemeikhian †  J. E. Everett ‡ 《Geophysical Journal International》1968,15(4):361-366

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