Detection of Discontinuities in Post-Stack 3D Seismic Data Using Inline and Crossline Filtering

Abstract

ABSTRACT. The detection of seismic discontinuities in reflection seismology has gained prominence in recent years due to the increase in the quality of acquired seismic data, thus enabling a better prediction of structures such as faults and fractures and contributing to the improvement of the interpretation of conventional and non-conventional reservoirs. In view of the aforementioned facts, we present a three-step filtering methodology for detecting discontinuities in post-stack 3D seismic data: (i) firstly, a horizontal filtering (inline followed by crossline) is applied to attenuate most horizontal and sub-horizontal events (mainly associated with reflections in the layers), thus enhancing vertical and sub-vertical structures; (ii) secondly, the Hilbert transform is applied to each dimension of the volume to obtain the complex volume, and finally, (iii) a phase rotation is applied to each dimension of the amplitude volume. The final result is the highlighting the fractures and flaws in the original volume. We illustrate the application of the new methodology in the pre-stack time-migrated of a 3D seismic data of the Alto de Cabo Frio area located between the Santos and Campos Basins. Numerical results demonstrate the aplicability of this methodology for detecting and mapping structural discontinuities in 3D seismic volumes, thus allowing for the delimitation of hydrocarbon reservoirs.