测井技术2009，Vol.33Issue(3)：293-298,6.
欠平衡钻井条件下钻井液的密度对中子孔隙度测井的影响
Effect of Drilling Fluid Density on Neutron Porosity in Under-balanced Drilling
摘要
Abstract
Low density drilling fluid is used for under balanced drilling. The neutron porosity log responses under this condition are different from normal borehole fluid conditions. Studied is the law of neutron porosity responses under the condition of low density drilling fluid by analyzing the analytical solution of double-group diffusion equation and using Monte-Carlo numerical simu-lation. The low density drilling fluid has borehole excavation effect on compensated neutron po-rosity logging, and by this way apparent porosity is lower than the true value. Besides, the lower the borehole fluid density, the bigger the borehole; the bigger the formation porosity, and the more obvious the borehole excavation effect. From the result of numerical simulation, obtained are the porosity correction formula for the borehole excavation effect and the neutron porosity correction chart for different density foam drilling fluid.关键词
中子孔隙度测井/欠平衡钻井/井眼挖掘效应/低密度/钻井液/蒙特卡罗模拟Key words
neutron porosity logging, under balanced drilling, borehole excavation effect, lowdensity, drilling fluid, Monte-Carlo simulation分类
天文与地球科学引用本文复制引用
王新光,张锋..欠平衡钻井条件下钻井液的密度对中子孔隙度测井的影响[J].测井技术,2009,33(3):293-298,6.基金项目
国家自然科学基金"随钻脉冲中子双孔隙度测井方法基础研究"(基金号:40874065)资助 （基金号:40874065）
