【作者】 雷芬丽；

【导师】 贺振华； 唐湘蓉； 文晓涛；

【作者基本信息】 成都理工大学 ， 应用地球物理， 2011， 硕士

【摘要】 碳酸盐岩礁滩储层的特点是,地层非均质强、物性差异小、多解性强,而且地震资料的品质也比较差,这就加大了碳酸盐岩礁滩储层精确预测的难度。而地震反演在精细油气勘探研究工作中所起的作用越来越重要,它能较真实地反映地下的地质构造和储层的岩性特征,大大提高钻井的成功率。本文在充分吸收前人关于碳酸盐岩礁滩储层的研究成果的基础上,应用目前使用较多的反演方法(递推反演、基于模型反演、约束稀疏脉冲反演等),详细地研究了每种反演方法的基本原理、关键处理技术以及适用条件等,并且分析了每种反演方法的优缺点,最后分析了实际应用效果,优选出适合本研究区碳酸盐岩礁滩储层预测的反演方法和处理流程。取得了以下成果和认识:1)对研究区的地质特征做了系统的认识,如碳酸盐岩礁滩的基本概念、主要分类及沉积环境等地质特征,总结了碳酸盐岩礁滩的地球物理响应特征。2)子波的选择影响着层位标定的效果,同时也直接影响着反演结果。本文分析了子波的长度、时窗、起跳时间以及其它影响因素,不断地进行层位标定和误差分析,估算最优化子波,使得最终反演结果的误差最小化。3)综合分析了三种反演方法的基本原理、适用条件以及优缺点。其中,递推反演虽然较忠实地反映了地震资料,但其效果却受制于原始地震资料,而且难以满足薄储层描述的要求,对于复杂的多井地区反演效果较差;基于模型反演充分利用了地震、测井以及地质资料,其反演结果分辨率大大提高,能够较好地反映井间储层的岩性和物性,但是由于该方法受初始模型的影响比较大,反演结果过于层状化;约束稀疏脉冲反演能够反映储层的横向变化,较忠实于地震资料,但是由于假定条件的限制有时候与实际条件不符,因此不能反映储层纵向细微的变化。4)本次研究的反演是基于反演软件STRATA,该软件中,基于模型反演过程中涉及的参数很多,例如硬约束、软约束、平均块的大小、迭代次数等,这些参数对于反演效果的影响比较大,因此每种参数都需要进行多次试验,反复验证,以便得出适合本区的最优化参数组合。5)反演方法评价。首先,结合本研究区的测井资料和地质资料,通过分析纵横向分辨率以及与测井资料的吻合度,选出适合本研究区的反演方法;然后对该方法的反演结果,结合实际资料进行地质解释。更多还原

【Abstract】 The reef flat reservoir was inhomogeneous, heterogeneous and differential, then it is very difficult to predict them. The seismic inversion plays a more and more important role in the research work of delicate oil-gas exploration. The technology can actually reflect underground geological structured and reservoir rock character, and can greatly raise the percentage of drilling hits. On the basis of fully consulting the study result of the reef flat reservoir, the thesis uses multiple methods of seismic inversion (including Recursive trace inversion, Model based inversion, Constrained spare spike inversion, etc). The author takes a detailed research on the basic principles, key technology and applied condition of every inversion methods, analyses advantages and disadvantages of each inversion method and applied effectiveness. The several results and my understanding are follows:1) It had been done a systematic understanding on the geological characteristics in the research area, such as the basic principles, main classification and sedimentary environment of the reef flat reservoir. The author has summarized geophysical response characteristics.2) Wavelet affects the effects of horizon calibration and finally results of the inversion. The author analyzed the length of wavelet, time windows, take-off time and other factors, continued to carry out horizon calibration and error analysis, estimate the optimal wavelet. And the error of the final inversion results is the smallest.3) The author has made a comprehensive analysis of principles, applicable conditions and pros and cons of three inversion methods. Recursive trace inversion reflects the seismic data more faithfully, but its effect subjects to the initial seismic data. It cannot meet the requests of thin reservoir description. Model based inversion makes full use of seismic, logging and geology data, greatly improves the resolution of inversion results, better able to reflect lithological characters and physical properties of reservoir. However, it has the relatively large impact of the initial model. Constrained spare spike inversion is able to reflect the lateral change of reservoirs and faith to seismic data. Because of the limit of assumptions, it cannot reflect slight vertical change of reservoirs.4) The inversion of a research based on STRATA of the inversion soft. In the soft there are a great many parameters in the course of model based inversion, such as hard constraint, soft constraint, the block time, the number of iteration and etc. These parameters influence the effects of inversion. Each kind of parameters needs to carry on the multiple trials. Finally the optimization parameters have been obtained for this area.5) Evaluation of impedance inversion. First of all, Based on logging data and geology data of the researched area, analyzing vertical and horizontal resolution and the coincidence with the logging data, the author has chosen the inversion method suitable for the area. Then, the geological interpretation about inversion results of this method has made.更多还原