塔里木盆地奥陶系碳酸盐岩缝洞型油气藏注水开发机理

Water injection development mechanism of carbonate fracture-cave reservoir in Ordovician,Tarim Basin

塔里木盆地奥陶系碳酸盐岩储层非均质性极强,流体性质复杂,开发难度大。注水是碳酸盐岩油气藏二次开发的主流方式,但目前依然对其注采机理缺乏系统梳理。文中结合现场注水开发实践,总结归纳了塔里木盆地奥陶系各类型油气藏注水机理及适宜的注水开发类型。分析认为对于单井单元,黑油、稠油油藏可通过注水吞吐替出剩余油,高含水油井可进行注水压锥降低含水率;挥发性油藏通过注水保压,抑制原油脱气;早期衰竭开发的高含凝析油凝析气藏可通过注水替出已析出的凝析油。对于多井连通井组,通过纵向替油和横向驱油可提高油藏采收率。

The Ordovician carbonate reservoirs in the Tarim Basin are of strong heterogeneity and fluid property is complex,which is difficult to develop. Water injection is the main method for the secondary development of carbonate reservoir,but now its injection and production mechanism is still lack of systematic review. In this paper,combined with the practice of field water injection,the injection mechanism of various types of oil and gas reservoirs in the Tarim Basin and the favorable water injection development types are summarized. According to the analysis,for the single well unit,concerning black oil and heavy oil reservoir,the remaining oil can be replaced by water injection. And high water oil wells can reduce moisture content by water injection pressure cone; The volatile oil reservoir can keep the pressure by water injection to depress the degassing; the early depletion-drive development of High condensate oil and gas reservoir can replace the precipitated condensate oil through water injection. For multi well connected well group,the oil recovery can be improved by vertical displacement and lateral displacement.