f Harmonic resonance structure and chaotic dynamics in the land vibrator system

Source-generated energy in vibrator records includes harmonies, subharmonics and chaotic oscillatory behavior. A simple, physically-based, nonlinear model of an ideal vibrator displays all of these behaviors. The model implies these nonlinear phenomena are the natural product of earth-vibrator interaction. The physical model is based on a form of the amplitude-dependent Duffing equation for forced oscillation in a damped, nonlinear system. The resultant resonances in the earth-vibrator system are assumed to be due entirely to the total vibrator mass reaction with an individual site position.