Comprehensive Utilization of Seismic Diffractions for Different Imaging Purposes
S.Z. Sun, D. Zhang, H.W. Xie, D.M. Zheng, Y.B. Liu, T. Peng and L. Chen
Event name: 77th EAGE Conference and Exhibition 2015
Session: Diffraction Modelling & Imaging
Publication date: 01 June 2015
Info: Extended abstract, PDF ( 1.15Mb )
Price: € 20
Seismic diffractions occur when propagating seismic waves strike on structural or lithologic abruptions in the subsurface, such as fault ridges, dissolved caves, pinch-out points, and abruptions on stratal or lithologic uniformities. Traditionally speaking, diffractions are often viewed as a special type of noise and can degrade the ultimate imaging quality especially for the deep. Nevertheless, considering that diffractions are mainly induced by discontinuities (e.g. faults and cavities), valuable information can be extracted from diffractions to better understand the subsurface geology from a different perspective. In this paper, a comprehensive utilization of seismic diffractions is introduced for different imaging purposes. On one hand, a specularity-weighted stack is applied to improve the imaging quality by suppressing disturbance of diffractions. On the other hand, diffractions are suggested to be extracted from dip-angle gathers with the help of generalized Radon transform, in order to detect subsurface discontinuities. Moreover, encouraging imaging results are achieved by employing the above two methods on a complex carbonate reservoir in Tarim Basin.