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211.
塔中117井储层烃包裹体研究及油气成藏史   总被引:8,自引:0,他引:8  
将一个烃包裹体视为一个小小的“油气藏圈闭”。若已知油气藏烃组分,应用PVTpro4.0油藏烃类流体相态平衡软件,可以获取油气藏圈闭的组分PVT相图及捕获压力参数。本文首先对TZ117井盐水包裹体和烃包裹体进行观察分析,将TZ117烃包裹体分成三期,然后在-170℃条件下利用喇曼测定烃包裹体中烃组分的相对含量,并输入PVTpro4.0油藏烃类流体相态平衡软件中做出烃包裹体PVT相图,确定烃包裹体捕获压力。根据烃包裹体捕获压力,恢复三期烃包裹体形成时的深度。结合TZ117埋藏史,研究TZ117井油气成藏史。  相似文献   
212.
自动雨量站降雨资料质量评估方法研究   总被引:8,自引:0,他引:8       下载免费PDF全文
利用19种不同型号的自动雨量站2005年6—9月在北京 (54511)、宜昌 (57461) 和南京 (58238) 3站的实测对比观测资料, 进行降雨资料质量评估, 不同的评估方法将会导致评估结果的差异。结果表明:采用自动气象站降雨资料和雨量筒人工定时观测记录作为降雨量参考标准对自动雨量站进行评估时, 由于降雨量参考标准本身存在的不确定性, 或多或少影响了评估结果的准确性。在广泛试验的基础上, 提出了采用基于各自动雨量站观测结果的拟合降雨量作为降雨量参考标准的新思路, 并对拟合降雨量的可行性、适用性以及计算方法进行了详细论述。  相似文献   
213.
The concurrent multiscale method, which couples the discrete element method (DEM) for predicting the local micro‐scale evolution of the soil particle skeleton with the finite element method (FEM) for estimating the remaining macro‐scale continuum deformation, is a versatile tool for modeling the failure process of soil masses. This paper presents the separate edge coupling method, which is degenerated from the generalized bridging domain method and is good at eliminating spurious reflections that are induced by coupling models of different scales, to capture the granular behavior in the domain of interest and to coarsen the mesh to save computational cost in the remaining domain. Cundall non‐viscous damping was used as numerical damping to dissipate the kinetic energy for simulating static failure problems. The proposed coupled DEM–FEM scheme was adopted to model the wave propagation in a 1D steel bar, a soil slope because of the effect of a shallow foundation and a plane‐strain cone penetration test (CPT). The numerical results show that the separate edge coupling method is effective when it is adopted for a problem with Cundall non‐viscous damping; it qualitatively reproduces the failure process of the soil masses and is consistent with the full micro‐scale discrete element model. Stress discontinuity is found in the coupling domain. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
214.
Chuan-Yi Tu 《Solar physics》1987,109(1):149-186
A new solar wind model has been developed by including in the model the Alfvénic fluctuation power spectrum equation proposed by Tu et al. (1984). The basic assumptions of the model are as follows: (1) for heliocentric distances r > 10 R , the radial variation of the power spectrum of Alfvénic fluctuations is controlled by the spectrum equation (1), (2) for heliocentric distances r < 10 R , the radial variation of the fluctuation amplitude is determined by the Alfvén wave WKB solution, (3) no energy cascades from the low-frequency boundary of the Alfvénic fluctuation power spectrum into the fluctuation frequency range, and the energy which cascades from the high-energy boundary of the spectrum into the higher frequency range is transported to heat of the solar wind flow. Some solutions of this model which, on one hand, describe the major properties of the Alfvénic fluctuations and the high-speed flow observed by Helios in the space range between 0.3–1 AU and, on the other hand, are consistent with the observational constraints at the coronal base have been obtained under the following conditions: (1) the spectrum index of the fluctuations is near to -1 for almost the whole frequency range at 10 R , (2) the particle flux density at 1 AU is not greater than 3 × 108 cm?2 s?1, (3) the solution is for spherically-symmetric flow geometry or the solution passes through the outermost of the three critical points of the rapidly diverging flow geometry with f max = 7. Some solutions passing through the innermost critical point of the rapidly diverging flow geometry with f max = 7 have been found, however, with too low pressure at the coronal base to compare with the observational constraints. Heat addition or other kind of momentum addition for r < 10 R is required to modify this model to yield better agreement with observations. A cascade energy flux function which leads to Kolmogorov power law in the high-frequency range of Alfvénic fluctuations is presented in Appendix A. More detailed discussions about the characteristics, the boundary conditions and the solution of the spectrum equation (1) are given in Appendix B.  相似文献   
215.
张景廉 《地质科学》1998,33(3):310-317
Pb、Sr、Nd同位素体系研究表明沥青与寒武纪、奥陶纪地层中的干酪根具有明显的同位素组成差异,表明来自异源。沥青Pb同位素组成具有明显的幔源与壳幔混合特征,而干酪根显示出壳源特征。沥青与干酪根的Nd同位素组成也存在着明显的差别,反映出老地壳源与新地壳源的明显差别。来自柯坪隆起大湾沟沥青的Nd-Sr同位素体系给出了晚元古的相关等时线,年龄分别为872Ma与1195Ma,可能代表了沥青的最早形成年龄。但来自塔北隆起的沥青其Sm-Nd体系显示出介于大湾沟沥青与干酪根之间的混合相关,表明具有壳源与幔源的二元混合成因。Rb-Sr和Pb-Pb等时线趋向和Pb模式年龄还给出加里东期(~440Ma)和印支期(~250Ma)的原油运移与沥青沉淀年龄信息。Nd模式年龄还表明柯坪-阿克苏地区存在太古宙基底(3.2-2.5Ga).塔里木油藏受深断裂控制。  相似文献   
216.
THEPOSITIONANDROLEOFWUHANCITYINTHEREGIONALECONOMICMACROSTRATEGIESOFCHINA①LiuMiaolong(刘妙龙)DeptartmentofSurveyingandGeoinforma...  相似文献   
217.
Weathering processes cause important changes in rock porosity. Besides porosity, distribution of pore sizes is significant for the identification of changes due to rock weathering and its effects on fabric. The formation of secondary porosity in different types of rock taken from different parts of Turkey was examined and the results are presented in this paper. The aim of this study was to observe changes in porosity due to weathering. Effective porosity, mercury intrusion porosimetry, and optical and scanning electron microscopy were used to evaluate the changes in pore geometry of the rocks. Additionally, the dry density, water absorption and uniaxial compressive strength of the rocks at different weathering stages were determined. Analysis of experimental data showed that microstructure of the rocks in relation to weathering is the main feature, which controls their physical and mechanical properties. The study revealed that fabric characteristics, particularly the pore and fracture geometry are very important characteristics for assessment of the behaviour of weathered rock.  相似文献   
218.
The flow field over Hainan Island and the Leizhou Peninsula in summer and winter is discussed with three-dimensional mesoscale model developed in the University of Virginia and using the representative meteorological data of January and July.Simulation results indicate that the local weather characteristics over the Hainan Island are distinctly influenced by theWuzhi Mountain terrain. The cloudy or rainfall weather over the northeast of the Wuzhi Mountain occurs easily, under proper large-scale conditions of flow, temperature and humidity. while west wind prevails. The overcast or rainfall weather is often induced by strong convection in the afternoon over west of the Hainan Island under easterly prevailing wind.  相似文献   
219.
全国地质勘查资质管理信息系统经过多年的建设,逐步建成涵盖地质勘查资质申报、审批发证、分析统计、监督管理和社会化服务为一体的完整的地质勘查资质管理信息化体系.本文详解了全国地质勘查资质管理信息系统的建设背景、建设思路、建设内容、系统功能、建设特点和推广应用情况等,总结了系统建设所取得的成效.  相似文献   
220.
A sizable total-pressure (magnetic pressure plus kinetic pressure) enhancement was found within the high-speed wind stream observed by Helios 2 in 1976 near 0.3 AU. The proton density and temperature and the magnetic magnitude simultaneously increased for about 6 h. This pressure rise was associated with a comparatively large southward now velocity component (with Vz – 100 km · s–1) and magnetic-field rotation. The pressure enhancement was associated with unusual features in the electron distribution function. It shows a wide angular distribution of electron counting rates in the low-energy (57.8 eV) channel, while previous to the enhancement it exhibits a wide angular distribution of electron count rate in the high-energy (112, 221 and 309 eV) channels, perhaps indicating the mirroring of electrons in the converging field lines of the background magnetic field. These fluid and kinetic phenomena may be explained as resulting from an interplanetary magnetic flux rope which is not fully convected by the flow but moves against the background wind towards the Sun.  相似文献   
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