川西坳陷鸭子河构造上三叠统须二段储层评价

RESERVOIR EVALUATION OF THE SECOND MEMBER OF THE UPPER TRIASSIC XUJIAHE FORMATION IN THE YAZIHE FORMATION OF WESTERN SICHUAN DEPRESSION

鸭子河构造上三叠统的勘探主攻目的层须家河组二段,钻井少,勘探难度较大。依据川鸭92等井岩心观察、测井响应特征划分出须二段辫状河道沉积、废弃河道沉积、越岸沉积三个沉积微相;根据物性资料的分析,并与相邻地区同层位的对比得出储层整体致密,但在须二段上部等次生溶孔和微裂缝发育层段孔渗条件较好。综合认为鸭子河构造须二段储集层砂体致密巨厚,储集性整体较差,但在须二段中上部仍有41.4m的Ⅰ类、Ⅱ类有利储层,是下一步勘探工作的重点工作区域。

The second member of Xujiahe formation is the major layer of Upper Triassic in Yazi River Structure, with little drilling wells and being difficult for exploration. According to cores and logging of some wells such as in the well Chuanya 92 etc., we divide three sedimentary micro-facies: braid channel, abandon bar and exceed bank. Through the analysis of physical characters and comparison with the layers of adjacent area, we conclude that the reservoir is generally compact, but some horizon has better developments of micro-fractures and secondary solution pores in the upper of second member of Xujiahe formation Finally, we summarize that the second member of Xujiahe Formation is generally composed with huge-compact sand rock., and though the storage ability is poor, there is still nearly 41.4m thickness of typeⅠand Ⅱ reservoir in the upper of the second member of Xujiahe formation.