定源回线瞬变电磁x分量视电阻率计算方法

THE METHOD FOR CALCULATING x-COMPONENT APPARENT RESISTIVITY OF TEM FIXED-LOOP

为获得定源回线瞬变电磁x分量的视电阻率,将定源回线等效为多个垂直磁偶极子,从而计算得到定源回线x分量瞬变响应结果。通过均匀半空间的瞬变响应值来拟合实测瞬变响应每一时间道的值,将均匀半空间的电阻率值定义为该时间道的视电阻率值。计算结果表明该方法有效,计算精度能够满足要求,可为定源回线瞬变电磁法多个分量综合解释提供必要的基础。

For the purpose of obtaining the x-component apparent resistivity of fixed-loop TEM, the authors made the fixed-loop equiva- lent to some vertical magnetic dipoles so as to calculate the x-component TEM response. The x-component apparent resistivity of fixed- loop TEM can be obtained when channel data of every time are fitted by response of uniform halfspace, and each halfspace resistivity can be regarded as corresponding channel＇s apparent resistivity. The calculation results indicate that the method is effective and its pre- cision is enough, and hence this tecnique can provide necessary basis for the comprehensive interpretation of two or three components with the fixed loop TEM method.