目前塔里木所打的平均井深最深的井在山前构造带,此处地层较特殊,有断层、压力体系不同、地层倾角大、存在多层复合盐层及流动性极强的“软泥岩”,因而普遍用高密度钻井液,目的是:①压住高压盐水层;②控制盐膏层的迅速蠕变;③抵抗“软泥岩”的塑性流动。由于是新探区,所用钻井液密度往往过高,使井下情况更复杂。根据现场调查结果,就使用高密度钻井液的方法提出以下几点意见。 At present, the wells with the highest average well depth in Tarim play in the piedmont tectonic zone, where the strata are rather special. There are faults and pressure systems, and the dip of strata is large. There are multi-layer composite salt layers and extremely “soft mudstones” Therefore commonly used high-density drilling fluid, the purpose is: ① pressure high pressure saline layer; ② rapid creep control of the salt layer; ③ resistance to “soft mudstone” plastic flow. Because it is a new exploration area, the drilling fluid used is often too dense, making the situation downhole more complicated. According to the field survey results, the use of high-density drilling fluid method to make the following observations.