Elastic envelope inversion using multicomponent seismic data without low frequency
C. Huang, L. Dong, Y. Liu, and B. Chi
State Key Laboratory of Marine Geology, Tongji University, Shanghai 20092, China
Received: 06 Nov 2014 – Accepted for review: 07 Nov 2014 – Discussion started: 05 Dec 2014
Abstract. Low frequency is a key issue to reduce the nonlinearity of elastic full waveform inversion. Hence, the lack of low frequency in recorded seismic data is one of the most challenging problems in elastic full waveform inversion. Theoretical derivations and numerical analysis are presented in this paper to show that envelope operator can retrieve strong low frequency modulation signal demodulated in multicomponent data, no matter what the frequency bands of the data is. With the benefit of such low frequency information, we use elastic envelope of multicomponent data to construct the objective function and present an elastic envelope inversion method to recover the long-wavelength components of the subsurface model, especially for the S-wave velocity model. Numerical tests using synthetic data for the Marmousi-II model prove the effectiveness of the proposed elastic envelope inversion method, especially when low frequency is missing in multicomponent data and when initial model is far from the true model. The elastic envelope can reduce the nonlinearity of inversion and can provide an excellent starting model.
Huang, C., Dong, L., Liu, Y., and Chi, B.: Elastic envelope inversion using multicomponent seismic data without low frequency, Nonlin. Processes Geophys. Discuss., 1, 1757-1802, doi:10.5194/npgd-1-1757-2014, 2014.