遗传算法在起伏地形下磁异常反演的应用

Application of genetic algorithm in the inversion of magnetic anomalies in rugged topographical settings

实际的地面磁法勘探往往是在山区进行,所测得的磁测结果也是沿地形起伏分布,这样往往会对磁异常曲线形态产生畸变,因此在起伏地形条件下,对磁测结果进行必要的反演,将会更明确地下目标地质体的位置与形态。本文首先模拟在水平条件下板状体的磁异常剖面曲线,检验算法的正确性,然后模拟在起伏地形下板状体的磁异常剖面曲线,并应用遗传算法对所得异常曲线进行反演并讨论其可行性,加入噪声并对其反演,讨论算法的抗干扰性,最后将其应用至实际找矿项目中。反演的结果表明,该方法在实际应用中具有一定参考作用。

In practice the ground magnetic prospecting is often conducted in mountainous region. The fact that the measured magnetic results are distributed along the rugged topography tends to inflict distortion on the shape of the magnetic anomaly curve. Therefore in rugged terrain the inversion of magnetic survey results is required to verify the position and the shape of the target geologic bodies under the ground. Firstly this paper simulated the magnetic anomaly curve of plate-like body in flat topographical settings and verified the results of algorithm. Then it simulated the magnetic anomaly curve of plate-like body in rugged topographical set- tings, and conducted inversion on resulted anomaly curve by applying genetic algorithm. After the feasibility of application of genetic algorithm was proved, noises were added in the inversion for the sake of discussion of the anti-interference performance of the algorithm. At last the method was applied in prospecting works in reality. The results of the inversion indicates that this method is referential to some extent to practical appli- cation.