重力异常处理中小子域滤波法的改进

An improvement on small sub-domain filtering method in processing gravity anomalies

在重力资料处理中,小子域滤波法会导致异常边界严重失真。为了弥补这一缺陷,提出一种改进的小子域滤波法,通过对子域剖分方式的改进以达到提升计算速度和控制异常边界失真的效果。通过模型试验对该方法的可行性进行验证,试验结果表明:重力异常数据利用改进的小子域滤波法多次迭代计算后,可以较好地反映地质体边界的分布情况,失真现象得到明显抑制;利用该方法描绘出虎林盆地断裂分布图,得到了25条断裂的分布情况,与已有的地质资料存在很好的对应关系。

Small sub - domain filtering method is one of common methods in processing gravity data. After processing gravity anomaly data, the cascade bands of gravity anomaly become more convergent, which could be used to reflect geological boundaries. Multiple iterations can improve the effect of convergence, but they also cause serious distortions of boundaries of gravity anomalies. In order to reme- dy the defect, we use an improved small sub -domain filtering method which raises calculation speed and alleviates the distortions of abnormal boundaries by improving partition mode. We conducted a model experiment to verify the feasibility of this method. The Model experiment shows that geological boundaries can be better reflected by gravity anomaly data after reusing the improved small sub -do- main filtering method several times, and the distortions of abnormal boundaries are well alleviated. We reused this method to process gravity anomaly data of Hulin Basin several times. Then we got the map of HuIin Basin faults distribution by the result, and a distribution of 25 faults was obtained. The result matches well with existing geological data.