姬塬油田A区长6储层特征研究及开发效果评价

Study on the characteristics and development effect of Chang 6 reservoir in Jiyuan oilfield

姬塬油田A区长6油藏位于鄂尔多斯盆地天环坳陷中-西部,为三角洲前缘水下分流河道沉积。发育长622、长631、长632三套含油砂体,单期砂体厚度薄(5~10 m),砂体呈北西南东向展布,砂体(油层)在纵向上、横向上连续性较差,且层间隔夹层多,属于长6超Ⅲ类油藏。2018年在该区开展小井距超前注水定向井试验,油藏整体开发效果差。2020年开始采用大斜度五点法注水开发,储层改造方式采用水力喷砂环空加砂体积压裂和全可溶桥塞体积压裂,取得了较好的效果。

The Chang 6 reservoir in A area of Jiyuan oilfield is located in the middle west of Tianhuan sag.It is an underwater distributary channel deposit of delta front.Three sets of oil-bearing sand bodies,Chang622,Chang631 and Chang632 are developed.The thickness of single stage sand body is thin(5~10 m),which spreads from northwest to southeast.The continuity of sand body(oil layer)in vertical and horizontal direction is poor,and there are many interlayer between layers,which belongs to Chang 6 super class III.In 2018,the pilot test of water injection directional well with small well spacing was carried out in the area.The overall development effect of the reservoir was poor.Since 2020,the high angle five point water injection method has been adopted.The reservoir reconstruction methods include hydraulic sand blasting annulus sand adding volume fracturing and fully soluble bridge plug volume fracturing,and good results have been achieved.