多种重力边缘识别方法在华北厚覆盖区断裂识别中的对比与应用效果分析OA

To effectively identify faults beneath thick cover in North China,this study systematically compared and evaluated the performance of six gravity edge detection techniques.The results indicate that the second vertical derivative is highly sensitive to shallow faults but is readily affected by noise,whereas the total horizontal derivative and analytic signal amplitude are more effective for detecting deeper faults,although their responses weaken in thick cover settings.The tilt angle and theta map can jointly extract information on shallow and deep structures but are prone to generating spurious boundaries.By contrast,the softsign function exhibited the best overall performance in our tests,effectively delineating major faults at different depths and within thick cover areas.Using a combined workflow incorporating these methods,we identified a possible concealed fault that is consistent with controlled source seismic and magnetotelluric profiles.We further inferred that the Jinhuo Fault may comprise two branches,one coinciding with the mapped trace and another trending N-E toward the Handan Fault,consistent with the spatial distribution of relocated earthquakes.In addition,an approximately E-W trending anomalous belt was detected west of the Jianchangying Fault,the origin of which may be related to a westward continuation of this fault.