Diffractions possess the potential to reveal subsurface discontinuities, such as faults, collapsed columns, and the rough edges of the salt body. We have developed a novel diffraction separation method that first flattens the dominant reflections and then identifies the diffraction wavefields through an orthogonal polynomial transform (OPT). Based on the planewave assumption and local slope, the reflection events can be predicted and flattened using plane-wave differential equations. To enhance the stability of the flattening process, a sliding window algorithm and three finite-difference forms are adopted. As the dominant coherent event, a reflection often corresponds to low-order coefficients in the OPT. To better preserve the diffraction energy, a time-varying order threshold is used when removing the dominant reflections. Two field data applications are presented to demonstrate the feasibility and effectiveness of the proposed diffraction separation strategy.
展开▼
