Virtual real source

Abstract

Estimation of the seismic source signature is an important problem in reflection seismology, especially in seismic imaging problems. Existing methods of source signature estimation (statistical methods and well-log-based methods) suffer from several drawbacks. Here, I introduce a method of extracting the source signature based on the theory of seismic interferometry, also known as the virtual source method. The only requirement for this method is to have a receiver location lie at the shot position whose source signature we want to estimate (not necessarily a zero-offset receiver). Through modeling examples, I show that the Virtual Real Source method produces accurate source signatures even for complicated subsurface and source signatures. Source signature of each shot can be extracted reliably if they all have similar amplitude spectra even though their phase spectra might be completely different. This method of source signature estimation not only gives accurate traveltimes and amplitudes of reflection events, but also has the potential to solve other issues, such as finding source radiation patterns, measuring intrinsic attenuation, and estimating statics.