Enhancing low- and high-frequency components of the seismic data to emphasise BSRs and bright spots and implications for seismic attribute analysis

Abstract

Abstract: The bandwidth of recorded seismic signals is typically limited and influenced by various factors, including seismic source characteristics, receiver response, recording parameters, and subsurface properties. It is always preferable that the data contain both high- and low-frequencies to obtain seismic data with a broad bandwidth to achieve the desired resolution. High frequencies facilitate the discrimination of thin layers, while low-frequency components play a crucial role in hydrocarbon exploration due to the attenuation of the high-frequency seismic signal within the hydrocarbon zone. In this study, a straightforward approach to enhance the low- or high-frequency components of seismic data is proposed to emphasise the BSRs and bright spots. The method involves the integration and differentiation processes, which correspond to linear scaling of the amplitude spectrum of the input seismic data. Through the integration process, the amplitudes of the low-frequency components in the seismic data are amplified, resulting in enhanced visibility of bottom simulating reflections (BSRs) and bright spots. These zones become more prominent in the instantaneous amplitude and frequency sections, and the reflections with reversed polarity, typically obtained from shallow gas accumulations and BSRs, are more continuous in the apparent polarity sections after the integration process. This situation makes the integration process suitable for the submarine fluid flow investigations. On the other hand, the differentiation process enhances the amplitudes of high-frequency components, thus enhancing the temporal resolution of the seismic data. This aspect makes the differentiation process well-suited for studying thin reservoirs or conducting facies analysis in complex sedimentation areas. Research highlights: Integration and differentiation processes correspond to linear scaling of amplitude spectrum. Integration enhances the low-frequency components of the seismic data. Differentiation increases the amplitudes of the high-frequency components. Integration makes the BSRs and bright spots more clear. Differentiation increases the temporal resolution. © Indian Academy of Sciences 2024.