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51.
V. I. Ferronsky S. A. Denisik S. V. Ferronsky 《Celestial Mechanics and Dynamical Astronomy》1996,64(3):167-183
The physical meaning of the terms of the potential and kinetic energy expressions, expanded by means of the density variation function for a nonuniform self-gravitating sphere, is discussed. The terms of the expansions represent the energy and the moment of inertia of the uniform sphere, the energy and the moment of inertia of the nonuniformities interacting with the uniform sphere, and the energy of the nonuniformities interacting with each other. It follows from the physical meaning of the above components of the energy structure, and also from the observational fact of the expansion of the Universe that the phase transition, notably, fusion of particles and nuclei and condensation of liquid and solid phases of the expanded matter accompanied by release of energy, must be the physical cause of initial thermal and gravitational instability of the matter. The released kinetic energy being constrained by the general motion of the expansion, develops regional and local turbulent (cyclonic) motion of the matter, which should be the second physical effect responsible for the creation of celestial bodies and their rotation. 相似文献
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55.
Mass heterogeneities and convection in the earth's mantle inferred from gravity and core-mantle boundary irregularities 总被引:1,自引:0,他引:1
Mass heterogeneities in the earth's mantle are retrieved from the gravity data and the topography of the core-mantle boundary as well as the topography of the earth's surface. A mantle circulation induced by the heterogeneities is modelled by solving the Stokes problem for incompressible Newtonian fluid. The derived models of mantle motions correlate well with the plate tectonics and point at a close relation between the surface tectonic activity and the processes in the vicinity of the core-mantle boundary. 相似文献
56.
57.
高、低煤阶煤层气藏地质特征及控气作用差异性研究 总被引:4,自引:0,他引:4
高、低煤阶煤层气地质特征及控气作用差异性是研究煤层气富集成藏的重要组成部分,是煤层气勘探开发理论研究过程中重要的基础性研究领域之一。本文以中国沁水、阜新盆地和美国粉河盆地等典型的含气盆地为例,探讨了高、低煤阶煤层气的储层物性差异,分析了构造控气和水文地质控气作用的差异性。研究表明,高煤阶气藏含气量高,CH4百分含量高,δ13C1值大于-38.75‰,储层渗透率变化小,储层改造难,构造热事件对煤层气的生成、富集贡献大,持续的水动力使气藏遭到破坏,且破坏幅度大,现今地下水格局对气藏的形成具有一定的影响;低煤阶气藏含气量低,CH4百分含量低,δ13C1值大于-49.11‰,储层渗透率变化大,储层易改造,煤热演化史及煤阶影响着煤层气的生成、富集,在煤层气生成过程中活跃的水动力是甲烷生成的主要的水文地质条件之一,但持续的水动力使气藏遭到破坏,且破坏幅度小,而合适的地层水矿化度则是低煤阶煤层气生成的重要条件,地下水格局对气藏的调整和改造起到决定性的影响。 相似文献
58.
Two algorithms for in-situ detection and identification of vertical free convective and double-diffusive flows in groundwater
monitoring wells or boreholes are proposed. With one algorithm the causes (driving forces) and with the other one the effects
(convection or double-diffusion) of vertical transport processes can be detected based on geophysical borehole measurements
in the water column. Five density-driven flow processes are identified: thermal, solutal, and thermosolutal convection leading
to an equalization, as well as saltfingers and diffusive layering leading to an intensification of a vertical density gradient.
The occurrence of density-driven transport processes could be proven in many groundwater monitoring wells and boreholes; especially
shallow sections of boreholes or groundwater monitoring wells are affected dramatically by such vertical flows. Deep sections
are also impaired as the critical threshold for the onset of a density-driven flow is considerably low. In monitoring wells
or boreholes, several sections with different types of density-driven vertical flows may exist at the same time. Results from
experimental investigations in a medium-scale testing facility with high aspect ratio (height/radius = 19) and from numerical
modeling of a water column agree well with paramters of in-situ detected convection cells. 相似文献
59.
Alessandro Tarantino Andrew M. Ridley David G. Toll 《Geotechnical and Geological Engineering》2008,26(6):751-782
This paper presents a review of techniques for field measurement of suction, water content, and water hydraulic conductivity
(permeability). Main problems in the use of field tensiometers are addressed and hints on how to improve tensiometer performance
are given. Advantages and limitations of instruments for indirect measurement of suction including electrical conductivity
sensors, thermal conductivity sensors, dielectric permittivity sensors, filter paper, and psychrometer are discussed. Techniques
for water content measurement based on dielectric methods are then presented. These include time and amplitude domain reflectometry
and capacitance. Finally, a brief overview of methods for measurement of water permeability in the field is presented. 相似文献
60.
松南海坨子—大布苏地区泉四段— 姚家组层序地层研究 总被引:2,自引:1,他引:1
根据工区内现有的钻井、测井和地震资料,应用以多级次基准面旋回为参照面的高分辨层序地层学理论与研究方法,对松辽盆地南部海坨子—大布苏地区的泉四段—姚家组地层进行了详细的层序地层研究,共识别出5个长期基准面旋回(相当于三级层序),9个中期基准面旋回(相当于四级层序),建立了研究区的层序划分方案,在连井剖面的层序地层对比基础上,建立了该区的地层格架,并对层序构成特征进行了分析,研究了储集层在层序格架内的分布规律,揭示出浊积砂体和三角洲前缘相的分流河道形成于基准面上升期,三角洲前缘相的河口坝、远砂坝和席状砂沉积形成于基准面下降期,指出浊积砂体和三角洲前缘相的远砂坝、席状砂沉积是研究区形成岩性油气藏的有利储集体。 相似文献