Convolution으로 정규화된 파동장을 이용한 송신원에 무관한 탄성파 완전파형 역산

Abstract

In conventional waveform inversion, geophysicists usually invert a velocity model as well as a source signature simultaneously. For a source-independent waveform inversion, we define a new objective function by multiplying both observed data and forward modeled data by the respective reference wavefields on the cross. For computation of the steepest descent of the new objective function, we exploit a matrix formalism originated from the symmetry of Green's function of wave equation. In this case, we calculate the steepest descent without explicitly computing the Jacobian matrix. Numerical structure of our algorithm resembles that of prestack reverse-time migration and waveform inversion.