A wave equation migration method for receiver function imaging: 1. Theory

摘要: [1] A wave equation-based poststack depth migration method is proposed to image the Earth's internal structure using teleseismic receiver functions. By utilizing a frequency number domain one-way phase screen propagator for field extrapolation in scheme, common conversion point (CCP) stacked functions are backward propagated construct subsurface structural image. The takes into account effects of diffraction, scattering, and travel time alternation caused by lateral heterogeneities, therefore it particularly useful imaging complex structures deep discontinuities overlain strong shallow anomalies. Synthetic experiments demonstrate validity variety laterally heterogeneous models. migrated images show considerable improvement over CCP recovering model features. Influences several factors on quality further investigated, including interstation spacing, noise level data, velocity used migration, earthquake distribution (incident direction source fields). On basis sampling theorem previous statistic results, we discuss relation spatial resolution signal-to-noise ratio with surface station spacing stacking. We that both stacking need be designed target-oriented way reliable efficient imaging. Our results also suggest careful consideration necessary designing seismic aimed at steeply dipping structures.