【作者】 罗美娥；

【导师】 肖安成； 谢朝阳；

【作者基本信息】 浙江大学 ， 地质学， 2010， 硕士

【摘要】 地应力是油气资源评价、油藏数值模拟、油气井工程设计的重要基础资料之一,是提高采油工程方案设计准确性和可靠性的基础保障。本研究采用了室内实验和有限元数值模拟相结合的方法确定X3地区的三维地应力分布特征。研究首先采用古地磁定向技术对岩心进行定向,并从保证测量精度和力求实验操作简单、成功率高角度出发,选用了差应变分析法和波速各向异性法测量地应力,两种方法联合应用,相互验证,较为准确地确定出X3地区实测岩心所在位置的地应力大小和方向；其次通过室内实验同步测出地层的动静态参数,建立动静态参数相关模型,实现动静态参数的转化,结合测井资料解释成果,给出X3地区储层力学参数纵向分布剖面,为后续三维地应力场的数值模拟奠定了基础；然后应用有限元三维数值模拟方法反演X3地区地应力场的空间分布,解决地应力测试只能确定地层中某一点或数个点,而不能对地应力场的空间分布进行确定的问题,拓宽了地应力测试成果的应用范围,数值模拟过程充分考虑不同层位之间的相互影响、各层厚度变化、岩层产状变化、断裂产状变化等结构构造,计算结果给出了主力油层顶、底界面在平面上的应力分布及沿垂向上任意剖面的应力变化；最后应用X3地区的地应力特征研究成果,有效地指导了该地区的射孔、压裂及防砂方案优化设计,为油田的全面有效开发提供了技术保障。更多还原

【Abstract】 Ground stress is one of the important data for oil and gas resource assessment, reservoir simulation and engineering design of oil and gas wells, and moreover, complete and precise information about ground stress is a fundamental guarantee of the reliability and accuracy for production engineering design.This paper investigated the 3D distribution of ground stress in area X3 by jointly using laboratory experimental study and finite-element numerical simulation. For the first, palaeomagnetic direction-finding technique was adopted to determine the orientation of the core samples. To ensure the precision of measurements, simplify the experimental operation and raise the ratio of success, both methods of differential strain analysis and nonisotropic diagnosis of wave velocity were applied to measure the ground stress. These two methods were used in combination, they verify their results each other, and as a result, the magnitude and direction of the ground stress was settled correctly at every location where core was sampled. For the second, the dynamic and static parameters of formation were measured simultaneously through laboratory experiments. The relationship between them was established, which makes the transform between them possible, from dynamic to static or from static to dynamic.With the achievement of well log interpretation incorporated as another information, the vertical distribution of mechanic parameters of formation was defined, which offers a basis for the subsequent numerical simulation of 3D ground stress field. For the third, finite-element numerical simulation was done to calculate the 3D distribution of ground stress by inversion method. This overcomes the limitation of ground stress measurement, which can only supply one or several points, not the whole body of the formation. Numerical simulation also widened the extent of application of the result of stress measurement. It takes into consideration the mutual influence of different layers over each other and the structural factors such as the heterogeneity of formation thickness and the mode of occurrence of formation and fracture.The simulation presented us with the horizontal stress distribution across the upper interface and the lower interface of the main layer, the vertical distribution of ground stress across any longitudinal profile.As the last work, the research achievement about the characteristics of the ground stress in area X3 is employed to optimize the project design of perforation, fracturing and sand control. It contributes a very efficient technological approach for the triumphant development of the whole oilfield.更多还原