Multiscale Analysis of Gravity Anomalies on East China Sea and Adjacent Regions

Abstract

AbstractThe form and depth of sedimentary basement and Moho basement are the main subjects in studies of deep Earth crust of ocean. Because the density difference of the two basements is prominent, which could reach 0.1 g/cm3 and 0.4 g/cm3, the gravity values are suitable to study the basements. However, the gravity anomalies include the whole lithosphere and upper mantle, the decomposition of the gravity field is important to study. Recently we have applied the wavelet analysis to decomposition of gravity field and obtained better results. In order to obtain the gravity anomalies corresponding to the sedimentary and Moho basement, we decomposed the free–air gravity anomalies of East China Sea and adjacent regions by using the two dimensional wavelet decomposition technique. The results show that the fourth order detail of the free‐air gravity anomalies mainly reflects the sedimentary basement and the fourth order approximation of the free–air gravity anomalies reflects the Moho. In this paper, we introduce the method of two dimensional multi–scale decomposition, show the result, and discuss its preliminary interpretation.