深井蠕变地层钻井液密度优化技术

深部地层盐岩钻井是钻井工程中的重大技术难题之一。由于盐岩性能的特殊性，当钻开井眼后盐岩蠕变，常造成井眼失稳、卡钻、固井后挤毁套管等事故，给钻井带来重大经济损失。结合山东胜科1井钻井工程，对深部地层盐岩及软泥岩等岩层的蠕变速率进行测试，采用三维数值模拟方法获得了盐岩及软泥岩的蠕变参数。并通过所获得的蠕变参数，对胜利油田东营区块盐岩及软泥岩井眼不同深度、不同钻井液密度下地层的蠕变速率进行了分析，获得了盐岩及软泥岩井眼许可钻井液密度。研究成果可以为钻井工程钻井液密度选用提供指导意义。

Drilling mud density optimum technique of creep stratum in deep borehole

Thanks to the creep behavior of salt rock, drilling hole in the salt deposit of deep stratum is a very important and difficult problem in petroleum engineering. The creep of salt deposit often causes oil borehole losing stability, blocking aiguille and demolishing oil well casing, and brings huge economic loss. Based on the measured result of the drilling hole diameter between the different time in Shengke 1 borehole drilling engineering, the creep velocities of the rock layer in the deep stratum are obtained. The exponent creep constitutive law is employed to analyze the creep velocity of rock layer in the three dimension numerical method. The creep parameters of salt rock and soft mudstone are obtained. The creep velocities of rock layer under different drilling mud densities and salt layer depth are also analyzed based on the obtained creep parameters. Considering the permissive stratum creep velocity during drilling, the optimum drilling mud densities under different salt layer depths are obtained. The research result can be used in drilling engineering,