Multi-attribute Seismic Analysis using Fractal Dimension and 2D 3D Continuous Wavelet Transform

摘要

3D post-stack seismic attributes provide an intuitive and effective way of utilizing seismic volumes for reservoir characterization and development, and further identification of exploration targets. Some of the seismic attributes can aid in precise prediction of geometry and heterogeneity of subsurface geological settings. These can also provide useful information on petro-physical and lithological properties when combined with well-log information. There exist numerous seismic attributes providing unique interpretation on some aspects of subsurface geology. Of these, proper demarcation of structural features, such as location and edges of faults, salt domes, their throw and extent, has always been of primary concern. In this paper we propose new multi-attribute seismic algorithms using fractal dimension and 2D/3D continuous wavelet transform (CWT). The use of higher dimensional wavelets incorporates information from ensemble of traces and can correlate information between neighboring traces in seismic data. The spectral decomposition based on CWT aids in resolving various features of geological interest at a particular scale or frequency, which when rendered with fractal attribute demarcates the boundaries between those. We apply these two algorithms separately to a seismic amplitude volume and co-render output volumes together with some weights to yield a final attribute volume incorporating information from above mentioned algorithms. We demonstrate the efficacy of these two algorithms in terms of resolution and proper demarcation of various geological structures on a real seismic data. Results illustrate better illumination and proper demarcation of various geological features such as salt domes, channels, faults etc. at a desired frequency and how simple mathematics can provide tools to extract most of the information from seismic data.