Converted-wave time domain registration using the inverted pseudo-PS-wave attribute section

Abstract

The main aim of the event registration of PP- and PS-waves in multicomponent seismic exploration is to provide the same time/depth domain data for further interpretation and application to reservoir characterization and hydrocarbon detection. Most registration methods are based on waveform similarity and phase consistency by correlating the stacked records, which may cause serious errors due to differences in PP- and PS-wave reflectivity. Our motivation was to develop a time matching workflow to improve the event registration of multicomponent seismic data and enhance joint interpretation techniques. In this paper, we present a prestack inversion method to obtain a pseudo-PS-wave (PPS) section based on prestack PP-wave gathers, and establish an attributes matching workflow based on the waveform similarity comparison of PP-, PS- and PPS-wave sections. We investigate the PP-wave prestack inversion method and the waveform similarity comparison of PP-, PS- and PPS-wave sections using synthetic data. The test on synthetic data clearly shows that the PPS-wave section has much better waveform similarity to the PS-wave section than the PP-wave due to the phase consistency of the reflectivity, increasing the correlation coefficient of waveform similarity to over 90% for PPS- and PS-waves from about 50% for PP- and PS-waves. The application to field data shows a very good improvement in the event registration, especially due to the partial nonexistence of events in the PP-wave section. The benefits for the time matching are also made evident by comparing the correlation sections of PPS- and PS-waves with PP- and PS-waves. The improved accuracy in event registration leads to better joint inversion and interpretation for the stratigraphic features and hydrocarbon detection in the subsequent applications.