泥浆侵入对阵列感应电阻率测井影响的数值模拟与校正

Numerical Simulation and Correction of Influence of Array-induction Resistivity Logging in Mud Invaded Reservoirs

研究证明,高矿化度泥浆侵入地层,电阻率校正量的大小与地层物性、泥浆矿化度与地层水矿化度比值以及泥浆的浸泡时间有关。通过数值模拟计算作出电阻率增大倍数与侵入时间以及孔渗指数的关系图版。利用图版法进行阵列感应测井电阻率侵入校正得到地层真电阻率,将其与试验结果及阿尔奇公式反推结果对比分析,图版法用于电阻率侵入校正存在局限性,阿尔奇公式毛管法适合高矿化度泥浆侵入校正,并且应针对不同地层孔隙结构和泥浆矿化度与地层水矿化度比值分别建立模型来进行电阻率侵入校正。

Study indicates that as the high salinity mud is invaded into formation, resistivity correction is related with ratios of formation physical property, mud salinity and the salinity of formation water and time of mud immersion. A chartboard of times of resistivity accretion multiple, mud invasion interval and porosity index is made through numerical simulation. True formation resistivity is obtained by using resistivity invasion correction of array-induction logging with the chartboard method. It is contrasted with experimental result and Archie conversion result. There is a limitation for resistivity invasion correction in chartboard method, Archie capillary method is for correction of high salinity mud invasion. Models are established for resistivity correction for different formation structures and mud salinities and for different salinity ratios of formation water.