Amplitude Spectrum and Edge Detection Attributes for Channels Discrimination and Geometry in Otumara Field, Niger Delta, Nigeria.

Abstract

Geological interpretation of seismic data traditionally fulfill two main objectives: solving geometry of structures with possible hydrocarbon accumulations and correlation of recorded seismic amplitudes with lithology, with the latter based on factors largely depending on interpreters’ previous experiences. Upon the transformation of seismic data into frequency domain using the Fast Fourier Transform, the phase spectra indicate lateral geologic discontinuities while the amplitude spectra delineates temporal bed thickness variability, thus making the spectral decomposition technique an effective tool in discriminating geobody within a 3D seismic data such as channel fills and associated lithofacies. From its inception, spectral decomposition has been used in highlighting channels. In many tertiary basins such as the Niger Delta, there is a direct correlation between strong amplitude, greater porosity and the presence of hydrocarbons. We have employed such frequency attribute complimented with similarity, illustrating real possibilities in identifying stratigraphic features of interest.