A Novel Static Correction Approach for Eliminating the Effect of Geophones—A Case Study in Coal Reservoirs, Ordos Basin, China

Abstract

Static correction is an essential step in seismic processing and it has an effect on the later steps of seismic processing, including velocity analysis, data stacking, and seismic inversion. During seismic data acquisition, a receiving point usually sets a geophone several times to receive the seismic data. The same geophone cannot be set at the same receiving point every time. If the geophones have different delay time, then the common receiving-point gather (CRG) will have multiple receiver statics. However, the receiver statics of a CRG are considered the same in conventional static correction. In this paper, based on common attitude gather (CAG), a novel static correction method is proposed to analyze the receiver statics of a CRG. Attitude indicates the tilt angles of the three components of a geophone. According to the different attitudes of geophones, CRG can be divided into multiple CAGs. When the difference technique is used to the novel method and the conventional method, the statics are analyzed with CAGs and CRGs, respectively. A field example demonstrates that the proposed method cannot only enhance the continuity of the event in the shot gather, but also smooth the gaps of the event in the CRG. The results suggest that the proposed method can eliminate the effect of differences in delay time of geophones on static correction.

Keywords

• static correction
• common attitude gather (CAG)
• seismic geophone
• geophone delay time
• coal reservoirs