Abstract:

Actual seismic exploration is corrupted by a variety of random noise. It is necessary to eliminate noise to extract the valid data. To address modeling method of ambient noise in land seismic exploration, this paper used classical chaotic Duffing system to model the ambient noise of forest belt area in China according to chaos of the ambient noise. It used MCMC(Markov Chain Monte Carlo) method to solve the system parameters according to nonlinear characteristics of Duffing system, and it contrasted simulated noise with actual ambient noise in terms of time-domain waveform, phase diagram, spectrum and Lyapunov exponent. The results show that the simulated noise records keep the chaos of the actual ambient noise, and the two noise have a good curve fitting in terms of time-domain waveform, phase diagram, spectrum. Therefore, the use of the Duffing system for land seismic ambient noise has certain prospects. The surrogate data obtained by the Duffing system is closer to the actual noise, which can provide new strategies to suppress noise and theoretical supports for seismic exploration in complex environment.

Key words: land seismic ambient noise, chaos, Duffing system, markov chain monte carb(MCMC) method