陆东凹陷交南断鼻上侏罗统砂岩的分形孔隙

FRACTAL PORES OF UPPER JURASSIC SANDSTONE IN JIAONAN FAULT-NOSE, LUDONG DEPRESSION

王泽中 钟宝荣 陈恭洋 李龙滟 周丽娟 李真济 廖兴明 吴仁山

Wang Zezhong Zhong Baorong Chen Gongyang Li Longyan Zhou Lijuan Li Zhenji Liao Xingming Wu Renshan

用SEM图片半自动分析方法,对陆东凹陷交南断鼻上侏罗统砂岩储层的28块样品进行的孔隙分形测量表明,该储层孔隙分形分为沉积分形和成岩分形两大类。沉积分形孔隙是由颗粒表面原始的不规则性产生的,分形维数一般小于2.50,分形孔隙度小于5%,分形孔隙占总孔隙的15%以下;成岩分形孔隙是由自生粘土矿物、自生石英和长石溶蚀所产生的,分形维数多大于2.50,分形孔隙度大于5%,分形孔隙在总孔隙中占50%～80%或更高。没有观察到碳酸盐胶结物产生的分形,泥岩中的孔隙几乎全为分形孔隙,而辉绿岩则无分形孔隙。

Fractal pore measurement of 28 samples collected from Upper Jurassic sandstone were made using a statistical analysis of structural features on fracture surfaces of SEM pictures.The fractal pore measurement indicates that there are two types of fractal pores. The depositional fractal pores and diagenetic fractal pores. The depositional fractal pores are formed of original irregular grain surfaces during deposition. The fractal dimension is less than 2.50,the fractal porosity is generally less than 5%, the fractal pores amount to 15% of the total pores. The diagenetic fractal pores resulted from authigenetic clay minerals, qaurts and dissolution of fieldspars. The fractal dimension of those fractal pores is greater than 2.50,the fractal porosity is usually higher than 5%, and the fractal pores are more than 50%-80%. No fractal pores caused by carbonate cements could be found. Almost all the pores in mudstone are fractal pores while there is no fractal pores in diabase.

10.11743/ogg19950406