四川盆地威远—资阳地区震旦系储层沥青特征及意义

四川盆地威远—资阳地区震旦系灯影组储层中存在大量固体沥青。该区沥青产状以溶孔充填和裂隙充填为主,晶间充填次之,微粒浸染最少。根据生物标志化合物特征,可将该区沥青分为2类:一类以威117井为代表,另一类以威118井、资1井和资6井为代表。沥青产状和沥青含量的分布与储层的储集性能呈正相关关系。沥青反射率值呈2段分布,各层段演化程度相似。结合地质条件,认为该区沥青多为后生—储层沥青,属原油热裂解成因。储层沥青的含量和分布指示了原油裂解气的气源灶。沥青的产状、等效镜质体反射率值分布和生物标志化合物特征表明该区存在2期沥青,且以第2期为主,第1期较少。在此基础上,结合构造演化史,恢复了该区天然气成藏史。 

CHARACTERISTICS OF THE SINIAN RESERVOIR BITUMEN IN WEIYUAN-ZIYANG AREAS OF THE SICHUAN BASIN AND ITS SIGNIFICANCE

There is large amount of bitumen in the Sinian Dengying Formation in Weiyuan-Ziyang areas,the Sichuan Basin.The occurrence of the bitumen is dominated by dissolution pore-filling and fracture pore-filling,with the intergranular-filling in the second and the micrograined disseminated-type in the least.Based on the biomarker characteristics,the bitumen can be divided into two types: one to Well Wei 117 as the representative,and the other to Wells Wei 118,Zi 1 and Zi 6 as the representative.There is a positive...