临盘油田盘40区块馆三7油藏是强水敏性高孔高渗油藏,砂岩储层渗透率为(344~1573)×10^-3μm2,孔喉粗大且孔径分布范围广。在水平井钻井过程中引起储层损害的主要因素为固相和滤液的侵入,以及黏土水化膨胀和钻井液与地层流体配伍性差。为此,优选出了能保护强水敏高孔高渗储层的纳米乳液暂堵钻井液。室内评价试验结果和在盘40区块8口水平井的应用结果表明:该钻井液具有较强的抑制黏土水化膨胀和分散的能力,储层损害半径小,渗透率恢复率大于85%,日产油量提高7~8倍,具有良好的储层保护效果,适用于强水敏高孔高渗和储层的保护。
The Nt3^7 reservoir of Pan 40 block in Linpan Oilfield is a high porosity, high permeability, and strong water sensitive reservoir. The sandstone permeability ranges from 344×10^-3 to 1573×10^-3μm^2. Pore diameter is big and its distribution is wide. Formation damages were mainly caused by filtrate of solids and fluid, clay hydrate expansion, the poor compatibility between drilling fluid and formation fluid. Therefore, a nanometer-emulsion diverting drilling fluid was selected to solve these problems. The application in eight horizontal wells showed that the drilling fluid has good inhibition and anti-sloughing, low damage radius, permeability recovery up to 85%. The oil rate increased by 7--8 times.