迪北地区致密砂岩储集层损害实验研究

Tight Sandstone Gas Reservoir Damages in Dibei Area of Tarim Basin:Experimental Study

致密砂岩气是中国非常规气开发的主要对象,深入研究造成致密砂岩储集层的损害机理,对于在开发过程中更好地保护储集层具有重要意义。结合塔里木盆地迪北地区侏罗系阿合组致密砂岩储集层地质特征,分析了孔隙结构及黏土矿物引起的潜在损害因素,进行了敏感性、水相圈闭等实验。结果表明,侏罗系阿合组储集层表现为中等偏强水敏、中等偏强液体速敏、中等强度的酸敏、较大水相圈闭等损害。要实现该致密砂岩气藏的高效开采,应控制入井液的类型、流速等,慎用酸液。

Tight sandstone gas is the main type and the direction of development of unconventional gas in China. Study on the mechanicsand factors for tight sandstone gas reservoir damage is more favorable to reservoir protection during the reservoir development and field op-eration. This paper presents the geological characteristics of the Ahe tight sandstone gas reservoir of Jurassic in Dibei area of Tarim basin,analyzes the potential factors of reservoir damage caused by pore structure and clay minerals,and makes the experiments of reservoir sensi-tivity and aqueous phase trapping. The results show that there exist such damages as moderate-strong water sensitivity,medium-strong fluidvelocity sensitivity,medium acid sensitivity and larger aqueous phase trapping in the Ahe reservoir,and it is suggested that the well fluidtype,flow rate and other related properties should be controlled,and acid liquid should be used very carefully for the purpose of efficientdevelopment of such a gas reservoir.