DETECTION AND DELINEATION OF THIN SANDSTONE RESERVOIRS

Abstract

Ever since the time of Widess (1973), seismic resolution of thin layers was limited.to measuring the length of the wavelet. Widess stated that the wavelet remains stable after a thickness of wavelength/4. Building on these foundations, Greg Partyka (1999) furthered our understanding by incorporating discrete Fourier transforms (DFT). This process inferred below these limits by using the tuning effect of frequency. Most of today's geophysicists believe a 1/ wavelength is a barrier and thickness of sediment cannot be determined below this limit but inferred. In this dissertation work, various attributes have been analyzed to delineate the thin beds defined by Widess. Synthetic model as that of Widess is generated using MATLAB to analyze the changes in amplitude, frequency and slope changes after. the Widess limit. Later on an area of thin bed was considered in Western offshore, India for detecting and delineating the thin bed 'using various techniques of conventional attributes, inversion and spectral decomposition. Among all the methods used spectral decomposition technique was found to be more effective in quantifying the area under thin beds. Slope method has further scope of enhancing the resolution.