低纬度地区ΔT异常的解释方法--“反号互余法”

“Opposite number and complementary angle” to the interpretation of magnetic ΔT anomalies in the low magnetic latitude area

非洲大部分区域,位于磁赤道带附近,属于低纬度地区,以水平磁化为主,磁性体产生的ΔT异常与处于中高纬度地区的中国大陆广大地区的ΔT异常特征差别较大,长期以来,人们主要通过化极的方法来对磁异常进行处理和解释,但往往因为精度较低和实用性较差等问题,很难真正使用.本文通过对各种形状磁性体磁场基本公式的分析与研究,分析了不同磁化条件下ΔT、Za、Ha异常特征的相互关系,提出了低纬度地区ΔT异常的解释方法——"反号互余法".该方法具有简单直观、易于实际操作的特点,不仅可以解决低纬度地区ΔT异常解释问题,而且对全球磁异常的认识也有重要作用.

Most of the African regions situated around the magnetic equator zone,they belong to the low magnetic latitude area,where rocks are magnetized horizontally and the property of ΔT is different from that in the other areas of Chinese Mainland which belong to the high magnetic latitude areas.For a long time,People mainly process and interpret the magnetic anomalies through the method of reduction to the pole（RTP）,but it is difficult to put into actual effect because of the low accuracy and poor practicality,etc.We make a detailed analysis and study to the shapes of magnetic body basic formula,analyze the abnormal characteristics of ΔT,Za,Ha in different magnetization conditions,put forward ＂opposite number and complementary angle＂to the interpretation of magnetic ΔT anomalies in the low magnetic latitude areas.This method is simple,intuitive and easily operated,it can not only solve the problem of the interpretation of magnetic ΔT anomalies in the low magnetic latitude areas,but also has an important role in the understanding of the global magnetic anomaly.