物探与化探Issue(3)：516-521,6.DOI:10.11720/wtyht.2014.3.18
基于“双烟圈”理论的瞬变电磁全期视电阻率计算
The calculation of full time apparent resistivity for transient electromagnetic survey based on "double smoking ring" theory
摘要
Abstract
Owing to the impact of inductor and capacitor of transmit coil, the transmit current of transient electromagnetic turns off like the ramp current. If we use the "single smoke ring" theory which fits for step turning off transmit current to make interpretation, the distortion will occur during the early and middle stage. According to the expression of second field induced voltage for ramp current, this paper presents interpretation with the"double smoke ring" theory, i.e., the secondary field induced voltage is made to be equiva-lent to the summation of secondary magnetic induction excited by two equal, opposite and successive"smoke ring" after the current is completely turned off. The secondary magnetic induction excited by every"single smoke ring" is calculated with forward and backward recurrence respectively. After that, the monotony of secondary magnetic induction excited by "smoke ring" is utilized to calculate the full-time apparent resistivity of ramp current and remove the distortion. At last, the numerical simulation model is used to confirm the correctness. The results obtained by the authors provide theoretical support for the full-time transient electromagnetic exploration and ex-planation.关键词
瞬变电磁/斜阶跃关断/双烟圈/全期视电阻率Key words
transient electromagnetic survey/ramp turn off/double smoke ring/full time apparent resistivity分类
天文与地球科学引用本文复制引用
许洋铖,吴燕清,崔靭,韩双..基于“双烟圈”理论的瞬变电磁全期视电阻率计算[J].物探与化探,2014,(3):516-521,6.基金项目
国家科技重大专项课题 （）
