【作者】 唐俊； 王琪； 廖朋； 郝乐伟； 田兵； 庞国印；

【Author】 TANG Jun~(1,2,3),WANG Qi~1,LIAO Peng~(1,2),HAO Le-wei~1,TIAN Bing~(1,2), PANG Guo-yin~(1,2) 1.Key Laboratory of Petroleum Resources Research,Institute of Geology and Geophysics, Chinese Academy of Sciences,Lanzhou 730000,China 2.University of Chinese Academy of Sciences,Beijing,100049,China 3.School of Mathematics,Physics and Biological Engineering,Inner Mongolia University of Science and Technology,Baotou 014010,Inner Mongolia,China

【机构】 中国科学院地质与地球物理研究所油气资源研究重点实验室； 中国科学院大学； 内蒙古科技大学数理与生物工程学院； 中国科学院地质与地球物理研究所 油气资源研究重点实验室；

【摘要】 在充分分析研究区长8段砂岩储层特征、主控因素及地层埋藏史和成岩史的基础上,应用数理统计方法,以现今孔隙度为约束条件,将孔隙度演化分为减小和增大两个过程,分别建立了鄂尔多斯盆地环县地区长8段砂岩储层从埋藏初始至现今的孔隙度随埋藏深度和地史时间变化的演化模型.结果表明孔隙度定量演化模型为一个4段式分段函数.机械压实和胶结阶段为孔隙度减小模型,是对埋深和埋藏时间的指数函数.次生增孔是由于地层酸性流体的溶蚀作用而产生的,主要发生在80～100℃的温度窗口内.因此,溶蚀阶段为孔隙度增大模型,是对埋深、埋藏时间及增孔过程的复合函数.溶蚀阶段结束后地层孔隙度为压实和保持阶段.最后进行实例验证,验证结果表明该方法建立的砂岩孔隙度定量演化模型符合地质实际,具有较好的应用效果.更多还原

【Abstract】 Thin section analysis indicated that the diagenesis of the sandstone reservoir in the research area had mainly undergone the processes of compaction,cementation and dissolution.Combined with the mathematical statistics method,the methodology was based on an analysis of tight sandstone reservoir characteristics, controlling factors and a study of the burial history and diagenetic history of the study area.With current porosity as boundary constraint conditions,the geological time and burial depth as variables,the whole porosity evolution from initial burial until the present was dividcd into two independent processes:porosity decrease and porosity increase,for which two mathematical models were established respectively.The quantitative simulation result indicates that the whole porosity-evolution quantitative simulation was a piecewise function with four sections.That is,the porosity decrease model for the mechanical compaction and cementation stages served a continuous exponential function with the geological time and burial depth as the variables,and the secondary porosity increase was caused by organic acid dissolution within a temperature window of 80～100°C.Therefore, the dissolution phase was of a porosity increase model,which was a composite function of the depth,burial time and porosity decrease amount.After the dissolution phase,the porosity was in the phase of compaction and maintenance.Finally,through the exemplification,it was verified that the porosity-evolution quantitative simulation established by the present researcher is consistent with actual geological conditions and can be applied to porosity calculation of any stratum in the study area.更多还原