桂西地区重力场小波多重分解及地质意义

重力场包含了各种密度不均匀体的叠加效应.为了更好地划分重力异常,尝试利用具有多尺度分析功能的小波分析进行重力场的分离.通过对桂西地区重力场进行小波多重分解,分离出埋藏较浅、尺度较小的源体和埋藏较深、尺度较大的源体,反映了不同深度和尺度地质体密度的不均匀性,较好地圈定了构造盆地、深部隐伏岩体,并直观地显示了其产状变化特征.因此,利用小波分析进行重力场分解具有较好的效果,值得进一步推广使用.

THE WAVELET MULTIPLE DECOMPOSITION OF THE GRAVITY FIELD IN GUIXI (WESTERN GUANGXI) AREA AND ITS GEOLOGICAL SIGNIFICANCE

The gravity field contains the superimposition effect of heterogeneous bodies with different densities.In order to divide the gravity anomaly more effectively,the authors tentatively used the wavelet analysis with the function of multi-scale analysis to separate the gravity fields.Through the wavelet multiple decomposition of the gravity fields in Guixi area,the authors distinguished the sources which had relatively shallower burial depth and smaller scale from those which had comparatively greater burial depth and larger scale.Such a result reflects the heterogeneity of the densities of geological bodies with different burial depths and different scales,and hence can quite effectively delineate tectonic basins and deep concealed rock bodies,with an audiovisual demonstration of their attitude variations.It is therefore concluded that the application of wavelet analysis to decomposing the gravity fields can yield fairly satisfactory result,and thus deserves further popularization.