Edge enhancement of gravity anomalies and gravity gradient tensors using an improved small sub-domain filtering method  

基于改进的小子域滤波的重力异常及重力梯度张量边缘增强(英文)

作　　者：蒋甫玉[1] 高丽坤[2] 

机构地区：[1]河海大学地球科学与工程学院,南京210098 [2]江苏省地质矿产勘查局第一地质大队,南京210041

出　　处：《Applied Geophysics》2012年第2期119-130,233,共13页应用地球物理（英文版）

基　　金：supported by the Scientific Research Starting Foundation of HoHai University, China (No. 2084/40801136);the Fundamental Research Funds for the Central Universities (No.2009B12514).

摘　　要：In order to enhance geological body boundary visual effects in images and improve interpretation accuracy using gravity and magnetic field data, we propose an improved small sub-domain filtering method to enhance gravity anomalies and gravity gradient tensors. We discuss the effect of Gaussian white noise on the improved small sub-domain filtering method, as well as analyze the effect of window size on geological body edge recognition at different extension directions. Model experiments show that the improved small sub-domain filtering method is less affected by noise, filter window size, and geological body edge direction so it can more accurately depict geological body edges than the conventional small sub-domain filtering method. It also shows that deeply buried body edges can be well delineated through increasing the filter window size. In application, the enhanced gravity anomalies and calculated gravity gradient tensors of the Hulin basin show that the improved small sub-domain filtering can recognize more horizontal fault locations than the conventional method.针对利用重磁资料增强地质体边界在图像中的视觉效果和提高地质解译的准确性问题,提出应用改进的小子域滤波方法对重力异常及重力梯度张量数据进行增强处理。根据滑动窗口子域平均选择原理,探讨了改进的小子域滤波方法在位场异常数据含有高斯白噪声时,不同窗口大小对地质体边界的识别效果及其在具有不同边界延伸方向地质体中的应用效果。模型试验结果表明,利用改进的小子域滤波对重力梯度张量数据进行增强处理,得到的地质体边界形态失真更小,且受滤波窗口大小、噪声以及地质体边界方向的影响较小;对深部场源体,通过增大滤波窗口的方式,可以较好地反映深部场源体的边界。结合黑龙江省虎林盆地重力异常以及计算的重力梯度张量的处理实例表明改进的小子域滤波法较传统的小子域滤波法增强了对断裂水平位置信息的识别。

关 键 词：Small sub-domain filter gravity gradient tensor edge enhancement gravity anomaly 

分 类 号：P631.1[天文地球—地质矿产勘探]