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461.
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潍北凹陷是昌潍坳陷的次一级凹陷盆地,也是胜利油田外围常规油气开采区。潍北凹陷孔店组二段发育了较厚的暗色泥页岩,是页岩气形成最有利层段,也是常规油气的生烃母岩。利用昌页参1井数据,结合以往资料,对潍北凹陷孔店组二段岩性特征,有机地球化学特征、矿物组成、泥页岩含气性特征等进行分析研究,认为孔店组二段上亚段下部和中亚段下部具备页岩气资源勘查开发潜力。 相似文献
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B. J. Travis C. Anderson J. Baumgardner C. W. Gable B. H. Hager R. J. O'Connell 《地球物理与天体物理流体动力学》2013,107(3-4):137-160
Abstract A comparison is made between seven different numerical methods for calculating two-dimensional thermal convection in an infinite Prandtl number fluid. Among the seven methods are finite difference and finite element techniques that have been used to model thermal convection in the Earth's mantle. We evaluate the performance of each method using a suite of four benchmark problems, ranging from steady-state convection to intrinsically time-dependent convection with recurring thermal boundary layer instabilities. These results can be used to determine the accuracy of other computational methods, and to assist in the development of new ones. 相似文献
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L.C. Watson J.D. Pritchard J.B. Hearnshaw P.M. Kilmartin A.C. Gilmore 《Monthly notices of the Royal Astronomical Society》2001,325(1):143-150
The visual triple system HD 9770 (BB Scl) has been the subject of a four-year programme of UVB ( RI )C photometry and H α échelle spectroscopy. Analysis of the data obtained over that period shows that star B, and probably also star A, of HD 9770 is a binary. The A system comprises a K1V star, which may be in a binary system with another K dwarf. The B system is an eclipsing binary of the BY Dra type in which both stars are chromospherically active. An orbital period of 0.476 525±0.000 013 d has been derived from the light curve in V . Physical parameters derived from analysis of the light curves in UBV ( RI )C are presented. 相似文献
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The evolution of a melt region produced by a large impact during Mars formation is addressed. While some impact induced melt is redistributed during crater excavation, sufficiently large impacts (much larger than basin forming impacts) generate an intact melt region which is retained beneath the excavation zone, i.e., a local magma ocean. Local magma ocean evolution depends on the effective rheology controlling large scale deformation of the solid part of the planet, mechanism of crystallization, and melt region size. Within the uncertainties of various parameters, two scenarios are possible. For sufficiently weak rheology or large melt region size, evolution is characterized by rapid extrusion and formation of a global magma ocean. For sufficiently strong rheology or small melt region size, in situ crystallization to a partially molten solid state occurs prior to isostatic adjustment. Subsequent to in situ crystallization, local magma ocean evolution depends on melt region size and efficiency of lateral redistribution compared to bulk conductive cooling. For large melt regions, lateral spreading occurs via plastic deformation and results in an asymmetric, global, partial melt layer. For small melt region size, viscous spreading viscous can result in bulk cooling below the solidus prior to formation of a global layer. A hypothesis for the origin of the hemispherical crustal dichotomy and Tharsis rise is suggested. The dichotomy is associated with a global partial melt layer produced by evolution of a large, local magma ocean. After dichotomy formation, evolution of a second, smaller, local magma ocean is related to Tharsis development. 相似文献
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We present an analysis of the spatial orientations of 1315 galaxies in 10 Abell clusters of BM type II–III (type II–III in the Bautz–Morgan system). It is found that the spin-vector orientations of the galaxies in six clusters (Abell 168, 426, 1035, 1227, 1367 and 1904) tend to lie parallel to the Local Supercluster (LSC) plane. The spin-vector projections of galaxies in six clusters (Abell 168, 1020, 1035, 1227, 1904 and 1920) are found to be oriented perpendicular with respect to the direction of the LSC centre. Three clusters (Abell 1920, 2255 and 2256) show a bimodal orientation: spin vectors tend to be oriented both parallel and perpendicular to the LSC plane. No dependence of radial velocity, distance and cluster magnitude on galaxy orientation is noticed. In a comparison with previous work, we noticed that the anisotropy might increase from early-type (BM type I) to late-type (BM types II–III and III) clusters. We notice a vanishing angular momentum for the less massive galaxy clusters (richness class 0). A significant alignment of the angular momenta of galaxies for massive clusters, e.g. the core of the Shapley Supercluster (richness class 4, M > 1015 M⊙ ), is found. 相似文献