圆弧插值在测井资料处理中的应用  

Application of Arc Interpolation in Logging Data Processing

作　　者：刘越 伍东 和志明 

机构地区：[1]中国石油长城钻探工程公司,北京102206

出　　处：《特种油气藏》2016年第6期136-140,共5页Special Oil & Gas Reservoirs

基　　金：中国石油天然气集团公司科学研究与技术开发项目"重大工程关键技术装备研究与应用/随钻电磁波成像与测录井解释支持系统研发"(2013E-3809)

摘　　要：具有圆周阵列型探头的测井仪器数据处理中,运用圆弧插值方法可以获得井筒横截面圆周上任意多个测量值,达到增加测井信息量的目的,为井眼状况和套管损伤评价提供技术支撑。利用适用于圆弧处理的余弦函数和第一类边界条件的三次样条函数组合插值法,将井筒横截面上分布的多个测井仪器探头测量值模拟成一个类圆周上的多个均匀排列的数据点,将类圆周模拟为余弦函数,通过第一类边界条件的三次样条函数插值法获得系数矩阵为三对角阵的方程组,使用追赶法求解方程组,得到井筒横截面圆周上的插值点数据。CIFLog-GeoMatrix软件声电成像和多臂井径成像测井资料解释结果表明,插值法形成的圆弧边界具有圆滑性,与实际井壁情况相吻合,且在井眼变形严重的区域能够避免出现与钻头尺寸不匹配的尖弧段,圆弧保形度较高。现场应用表明,经圆弧插值法处理后的多臂井径成像测井资料能够鉴定多种类型的套管损伤,且鉴定效果较好,效率较高。In the processing of logging data with circular array probe,any number of measurements on the circumference of wellbore cross-section can be gained by arc interpolation. This method could increase logging information and provide technical support for borehole environment and casing damage. The measurements from multiple probes distributing on the wellbore cross-section can be simulated by the cosine function for arc processing and cubic-spline combination interpolation of direct boundary condition. These measurements can be converted into a plurality of data points uniformly arranged on an analogous circumference. The analogous circumference is simulated as a cosine function and an equation set is gained by the cubic- spline combination interpolation of direct boundary condition. The coefficient matrix of this equation set is a triangular matrix and chasing solution can be used to obtain the data of interpolation points on the wellbore cross-section. The logging interpretation of acoustic-electric imaging and multi-arm caliper imaging from the CIFLog-GeoMatrix software indicates that the smoothing arc boundary gained by arc interpolation is perfectly consistent with that of actual borehole wall. In addition,this processing method with high shape-preserving capability could avoid sharp arc segment that mismatches drilling bit size in the interval with severe borehole deformation. Field application shows that multiple kinds of casing damage can be accurately and efficiently identified by multi-arm caliper imaging data after arc interpolation processing.

关 键 词：圆弧插值 测井数据处理 多臂井径成像测井 三次样条函数 CIFLog-GeoMatrix软件 

分 类 号：TE319[石油与天然气工程—油气田开发工程]