Preferential filtering method and its application to Bouguer gravity anomaly of Chinese continent

We presented the preferential filtering method for denoising and anomaly separation of gravity data based on Green's equivalent-layer concept and Wiener filter. Compared to the conventional upward continuation and the preferential continuation, the preferential filtering method has the advantage of no requirement of continuation height. The data test on the synthetic gravity data showed that the preferential filtering method produced better separation of gravity anomaly than both the band-pass filtering and the conventional upward continuation. We then used the preferential filtering method to suppress the noise in the Bouguer gravity anomaly data of Chinese continent and separate the regional gravity anomaly. Then with constraints of the scattered Moho depth information deduced from the deep seismic detection, the regional gravity anomaly was inversed to obtain the Moho depth distribution of the whole Chinese continent. The preferential filtering method provides technique support for the deep detection and tectonic study of Chinese continent.