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71.
72.
特低渗透砂岩储层可动流体变化特征与差异性成因——以鄂尔多斯盆地延长组为例 总被引:1,自引:0,他引:1
特低渗透砂岩储层微观孔隙结构复杂,流体赋存状态不同于常规储层,利用核磁共振技术对鄂尔多斯盆地延长组3个层位样品的可动流体变化特征与差异性成因进行了分析。结果表明,样品T2谱分布主要表现出4种形态、T2截止值中等—偏高、可动流体参数变化幅度较大;沉积和成岩作用差异导致微观特征参数不同,造成各层位可动流体参数复杂变化;渗透率较小时,可动流体参数变化幅度大,当渗透率增大到一定程度后,可动流体参数数据点收敛,变化幅度减小;储层物性、孔隙(尤其是次生孔隙)发育连通程度、微裂缝的发育程度、粘土矿物的存在形式及其对孔隙的充填程度等微观孔隙结构特征变化是可动流体参数差异性产生的主要原因。可动流体参数本身就是储层诸多微观特征参数的综合反映,应在储层评价中予以考虑。 相似文献
73.
仇山酸化钙基膨润土的 27Al和 29Si 魔角旋转核磁共振谱及脱色率研究 总被引:1,自引:0,他引:1
对用不同酸度处理的仇山钙基膨润土进行了化学分析、X射线衍线(XRD)、^27Al和^29Si魔角旋转核磁共振(MAS NMR)、吡啶吸附样品的红外光谱(IR)、比表面积、阳离子交换容量(CEC)和脱色率等测定。结果表明,随着处理酸度的增加和蒙脱石中阳离子的溶出,它的d(001)的衍射强度降低,同时其Si和Al原子局域结构环境发生了显著的改变,Al原子由Al^Ⅵ变成Al^Ⅵ,Si原子由Q^Si(0Al)结构向Q^4Si(0Al)和Q^3Si(1OH)结构转变。八面体片阳离子的溶出和Si,Al原子局域结构环境的转变,显著地增加了比表面积和孔结构;Al^Ⅵ向Al^Ⅵ的转变形成了Lewis酸中心,而Si原子局域结构环境的改变形成了Br φnsted酸中心。膨润土脱色率随处理酸度增加的本质原因是在Si和Al原子局域环境的变化过程中,在其表面分别形成了Brφnsted酸中心和Lewis酸中心。 相似文献
74.
简单介绍了核磁测井数据弛豫谱反演方法原理 ,用混合编程方法和动态连接库技术 ,将用FORTRAN语言编写的核心处理模块转换为动态连接库 ,并在C++语言中动态调用。应用快速应用程序开发工具完成了图形用户界面的核磁测井数据处理软件设计。 相似文献
75.
27Al,29Si MAS NMR studies of kaolinite and its thermal transformation products show that in the kaolinite-mullite reaction series
there is an extensive segregation of Al2O3 and SiO2 and the reaction of Al2O3 with SiO2 to form mullite is the main path of mullite formation. At about 850° C, the peak intensity of A1(V) reaches its maximum and
with the further rise of temperature the A1(V) signal completely disappears. At about 950°C, γ-Al2O3 accounts for about 71% of the material phases containing Al atoms. In the series there is no obvious presence of Al-Si spinel.
The27Al and29Si MAS NMR spectra show that there is an obvious difference between the temperature points for Al-O2(OH)4 octahedral sheet collapsing and Si-O4 tetrahedral sheet breaking down. 相似文献
76.
An algorithm for the stratigraphic correlation of well logs 总被引:3,自引:0,他引:3
Franklin Kemp 《Mathematical Geology》1982,14(3):271-285
This paper describes an algorithm for the semiautomatic shifting and stretching of one well log relative to another until a local maximum correlation coefficient between the two logs is found. The algorithm grew out of a graphical interpretation of the standard shift correlation procedure. The algorithm does not interpolate data and it is as computationally efficient as the standard correlation method using linear interpolation. The algorithm is generalized to the simultaneous stratigraphic correlation of separate sections from two well logs and two examples of its operation are given. 相似文献
77.
地下介质和物流运移的综合成像方案 总被引:2,自引:1,他引:1
郭履灿 《CT理论与应用研究》2003,12(3):53-55
目的:借鉴描述冷暖气流等多科参数(气压、温度和湿度、风速、风向、水蒸汽密度等)的动态三维显示,初步解决了暴雨和天气预报的难题,促进了天气预报的成功,在地球科学中起到了示范作用。从而联想到在地下介质和物流运移过程的综合成像。资料和方法本文总结了地面和地下探测手段的多样性,列举了天然地震CT的精度已能达到l~5km的量级,地震人工曝破作勘探可以达到10~20米的成像分辨率,地下电阻率和电磁成像可以分辨到l—2米的量级;将磁共振(MRI)用于地下成像可得到地下水分布的动态观测深度,概括了这三方面的前沿性进展,并与震源的空间分布和地应力相结合,进而设计出综合性的观测系统。发展地下水、岩浆、地应力和活断层结构和地震破裂面等多种参数的动态显示,设计出一套观测系统,并阐述言的科学意义。结果和结论:将以上三方面的观测方法综合起来;可在有火山喷发危险的区域,具有诱发地震危险的大型水库地区,和在发生了强烈地震的地区,为了抗震救灾,有必要同时进行以上三个系统的观测,引入可视化数字科技,便于了解地下水和岩浆的过移过程及相关参数的变化,并配合当前已有的综合监测系统(震源空间分布、地震应力和其他前兆等),服务于保障大型水库的安全、促进强震预测,及对火山喷发、矿井塌陷、突出的监测预报。 相似文献
78.
Electrical borehole image logs yield high-resolution information about variations in micro-resistivity along the borehole wall. To interpret these variations in terms of sedimentary structures and lithofacies types, calibration with real rock is needed. Normally, the only real rock available is core, and this only provides one-dimensional information. In this paper, the interpretation of fluvial facies types from borehole image logs was established by direct comparison with outcrops. Four fluvial facies associations were established in an outcrop study of a low net-to-gross fluvial succession: (i) meandering rivers, (ii) braided rivers, (iii) crevasse deltas, and (iv) crevasse splays. The lithofacies characteristics and palaeocurrent distributions of each fluvial facies association were established. Two 200 m deep wells were drilled behind the cliff face outcrops. One well was cored to a depth of 150 m and borehole image logs were recorded in both wells. The wells were correlated with the outcrop. The borehole image logs were analysed by their vertical colour succession and the dipmeter pattern. Image log facies were established, and these were interpreted in terms of the fluvial facies associations encountered in the corresponding outcrops. The study of borehole image logs yields a set of diagnostic criteria for a detailed fluvial facies interpretation and the establishment of depositional trends, and thus provides a powerful tool for the direct interpretation of fluvial facies in a reservoir setting. 相似文献
79.
29Si,27Al MAS NMR and IR spectra of rnonophase K-feldspars (sanidine, orthoclase and microcline) and Na-feldspars (monalbite, anorthoclase
and low albite) in different structural states have been studied. The NMR and IR spectra of K-feldspars and Na-feldspars vary
regularly along with their degrees of Si/Al ordering evolution. Si in orthoclase occupiesT
2m,T2o andT1m, and the high-temperature Na-feldspar (monalbite and anorthoclase) coincides in29Si,27Al NMR and IR spectra. Moreover, all the high-temperature Na-feldspars and sanidine have the same27Al NMR and IR spectra.
Project supported by the Foundation of Laboratory of Magnetic Resonance and Atom and Molecular Physics, Wuhan Institute of
Physics, Chinese Academy of Sciences. 相似文献
80.
Relation between source rock properties and wireline log parameters: An example from Lower Jurassic Posidonia Shale, NW-Germany 总被引:1,自引:0,他引:1
The relationships between source rock quality and wireline log parameters were established for the Lower Jurassic Posidonia Shale, the most prolific petroleum source rock of Central Europe. Wireline logs used are the gamma ray spectrometry, density, sonic and various resistivity logs. The organic geochemical parameters considered include the organic carbon content, hydrogen index, and the hydrocarbon potential expressed by pyrolysis yield. The case history presented is based on a continuous core through the entire Posidonia Shale interval from a location where this source rock is immature. Care was taken to detect and to avoid samples and log values influenced by bore hole roughness and fractures. Fair correlations were observed only between uranium content from gamma ray spectrometry log and organic carbon content. No correlation was recognized between uranium content and kerogen type as defined by hydrogen indices. For various reasons density, sonic, and resistivity logs did not provide useful data in this study.Three rock units with irregular, high and low uranium contents could be differentiated. Possible causes for this tripartition are different environments during deposition and postdepositional redistribution of uranium during early diagenesis and in association with fractures. 相似文献