岩石泊松比的测井计算方法研究

岩石泊松比不仅是计算其它岩石力学参数的基础,也是计算地层应力及3个地层压力的重要参数之一.该参数计算的准确与否直接影响到井壁力学稳定性评价的准确性.由于常常缺乏横波时差测井资料,以致不能准确地计算岩石的泊松比.针对这一不足,充分利用川东地区罗家寨构造LJ9井纵波时差、地层密度等常规测井资料,在对横波时差进行构建的基础上来建立岩石泊松比的计算模型.将该方法应用于同一构造LJ2井的泊松比的计算中,结果表明,与利用实测横波时差计算的泊松比相比,误差较小,完全能满足石油工程的需要.

On Calculating Method of the Rock Poisson Ratio Using Well Logging Data

Rock Poisson ratio is not only the basis calculating the rock mechanics parameters, but also is one of the significant parameters for calculating formation stress and three formation pressures. Whether the parameter is accurately calculated or not directly affects the evaluation precision of borehole mechanics stability. Since shear wave time difference is frequently not gained, the rock Poisson ratio cannot be accurately obtained. For this reason, compressional wave time difference and formation density provided by conventional logging in LT9 well, Luojiazhai structure in the east Sichuan Basin are sufficiently used to build the math model of rock Poisson ratio based on the constructed shear wave time difference model. The above approach is used to LJ2 well's Poisson ratio calculation. Compared with Poisson ratio calculated with the actual measured shear wave time difference, the error resulted from the above approach is little, so that it completely meets the requirement of the petroleum logging.