Seismic Data Stacking Based on Time-varying Mapping
(2.BGP Seismic Data Processing Center, Zhuozhou, Hebei Province, China 072751)
(3.BGP Acquisition Technology Center, Zhuozhou, Hebei Province, China 072751)
(4.School of Earth Science and Engineering, Hebei University of Engineering, Handan, Hebei Province, China 056038)
【Abstract】Due to the existence of large source-receiver elevation differences in ocean-bottom-node (OBN) and mountain data, conventional common-midpoint (CMP) stacking based on the assumption of horizontal land surface is no longer feasible. We propose common reflection point (CRP) stacking based on time-varying data mapping as an alternative. We use stacking velocity to calculate time-varying CRP sampling points in output sections. At each CRP sampling point, two-way time is calculated using a modified double-square-root formula for NMO correction. We can use this method to improve the stacking quality for OBN and mountain data, and we also can obtain accurate stacking velocity for subsequent processing. Model and field data tests show that CRP stacking based on time-varying data mapping is better than CMP stacking.
【Keywords】 common reflection point; time varying; data mapping; stacking;
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