CSAMT静态偏移的转换相位法校正  

Correction of CSAMT static shift using transformed phase

作　　者：石显新[1,2] 闫述[3] 陈明生 傅君眉[2] 

机构地区：[1]中煤科工集团西安研究院,陕西西安710077 [2]西安交通大学电子与信息工程学院,陕西西安710049 [3]江苏大学计算机科学与通信工程学院,江苏镇江212013

出　　处：《石油地球物理勘探》2011年第5期802-809,836+666-667,共8页Oil Geophysical Prospecting

基　　金：国家重点基础研究发展计划(973计划)项目(2006CB202207);江苏大学高级人才启动基金项目(05JDG054)联合资助

摘　　要：静态偏移可使CSAMT实测视电阻率曲线在双对数坐标中产生平行的上、下移动,导致资料解释的精度降低。相位数据与视电阻率的平行移动无关,只与其斜率有关,且相位曲线中同样包含与电场或磁场相同的地质信息,但在实测中不易得到高质量的相位曲线。本文将实测数据中的单分量电场数据转换成相位曲线,可有效地消除静态偏移的影响,且不存在校正不足或过量的问题,也不受测点布置的限制。用转换相位进行定量反演的结果和用电场幅值曲线反演的结果相差无几,在转换中引入的误差可以忽略不计。在CSAMT资料处理、解释中,相位曲线不仅可以和EMAP法一样作为常规的校正静态偏移的处理方法,而且可以和视电阻率数据一样作为常规的资料解释方法。The static shift makes measured apparent resistivity curves up and down parallel shifts in double logarithmic coordinate system.This badly impacts the accuracy of interpretation.Phase data have no relation with parallel shifting of apparent resistivity curves.They only have relation with their slope and the information contained in phase curves are as same as in the electric field or the magnetic field.However,high quality phase data are difficultly measured in practice.In this paper,transformed phase curves from single electric field component in measuring data are used to remove static shifts.The results show that the approach is effective.There are no under-corrected or over-corrected problems and no limitations of the observation point spread.The litter difference between the results of quantitative inversion with transformed phase and the results of inversion with amplitude of the electric field can be ignored.Just as EMP method in CSAMT data processing and interpretation,phase curves can be used not only for static shift correction but also in data interpretation with apparent resistivity.

关 键 词：CSAMT 静态偏移校正 电场分量 转换相位 相位反演 

分 类 号：P631[天文地球—地质矿产勘探]