摘要
塞拉利昂位于赤道附近,属于低纬度地区。在低纬度区,以水平磁化为主的条件下,磁性体所产生的ΔT磁异常以负异常为主,正异常伴生。通过对磁资料进行倒相180°、化赤、化极处理方法的对比,认为在不考虑剩磁、磁性体退磁作用的情况下,结合当地地质情况,倒相180°的处理方法能够展现该区的磁场特征,以此作为基础资料对全区的磁异常进行解释。利用不同高度的向上延拓处理,有效地排除了浅层干扰,突出深层异常特征,再结合最大坡度法、经验切线法、欧拉奇次方程法确定其磁性体的埋深和水平大致位置,最后,采用二度半人机交互反演拟合磁性体大致的形态,通过布设钻探施工,验证结果与推断吻合较好。
Sierra Leone is located in a low magnetic latitude area around the magnetic equator. In view of the fact that the magnetic bodies of ΔT anomaly mainly produce negative anomalies associated with some positive anomalies at the low latitude area which is mainly under the condition of horizontal magnetization,the authors tried to make a comparative study of the magnetic body under the condition of demagnetization effect in combination with local geological conditions without considering remanent magnetism. The authors adopted the method of inverter 180 ° of experimental data and then made interpretation of the data. The upward continuation of different heights was utilized so as to effectively eliminate the shallow interference and highlight the anomaly characteristics of the deep layer. In combination with maximum gradient method,experience tangent method and Euler＇s equation method,the buried depth of the magnetic body and the level of general location were determined. Finally,2. 5 D interactive inversion was adopted to fit roughly the shape of the magnetic body. Drilling result is quite consistent with the inference.
出处
《物探与化探》
CAS
CSCD
2014年第4期649-653,共5页
Geophysical and Geochemical Exploration
基金
国外矿产资源风险勘查专项资金项目(201210B02300203)
关键词
高精度磁测
低纬度地区
2.5D反演
塞拉利昂洛琴铁矿
high-precision magnetic survey
low-latitude area
2.5 D inversion
the Roten iron deposit in Sierra Leone
