Premium
Wave refocusing for linear diffractor using the time‐reversal principle
Author(s) -
Keydar Shemer,
Landa Evgeny
Publication year - 2019
Publication title -
geophysical prospecting
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.735
H-Index - 79
eISSN - 1365-2478
pISSN - 0016-8025
DOI - 10.1111/1365-2478.12784
Subject(s) - diffraction , geology , point (geometry) , seismic wave , vertical seismic profile , karst , seismology , geometry , optics , physics , mathematics , paleontology
One of the problems encountered in a variety of near‐surface investigations is detecting and mapping localized heterogeneities. The heterogeneities may be classified under two kinds of objects: (1) a point diffractor that can be considered as an approximation of a small quasi‐isometric, such as small karstic cavities and caves; (2) a linear diffractor roughly approximating an elongated object, such as a tube or fault plane. The point and linear diffractors generate two types of seismic diffraction: tip and edge waves, respectively. During the last few decades, different methods were proposed by many researchers for detecting these heterogeneities utilizing seismic waves diffracted by them. An alternative method for detecting point diffractors using a time‐reversal principle combined with focusing analysis is proposed in this study: we present an extension of the time‐reversal method for linear diffractors. It consists of a coherent summation of seismic energy along edge‐diffraction traveltimes. Real data examples show the feasibility and efficiency of the proposed method.