Constraining Stochastic Inversion with Frequency Domain Seismic Signature for Seismically Thin-bed Interpretation

2013 International Conferences on Geological, Geographical, Aerospace and Earth Sciences

Purnomo, Eko Widi^1 ; Ghosh, Deva Prasad^1

Center for Seismic Imaging, Faculty of Petroleum Geosciences Universiti Teknologi, Petronas, Malaysia^1

关键词: Accuracy and precision;    Frequency domains;    Limited information;    Seismic amplitudes;    Seismic attributes;    Seismic inversion;    Seismic signatures;    Thin-bed interpretation;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/19/1/012002/pdf
DOI  :  10.1088/1755-1315/19/1/012002

来源: IOP

【 摘 要 】

An alternative technique in interpreting thin-bed structure has been developed. The technique involved stochastic inversions which use frequency domain energy spectral attribute as a constraint instead of time domain seismic amplitude. Maximum Amplitude Weighed Integrated Energy Spectra is a proposed energy spectral attribute which was used to constrain the stochastic process. Amplitude Weighed Integrated Energy Spectra is a deployed seismic attribute obtained by multiplying integrated energy spectra with maximum amplitude of a seismic trace. It is shown that Amplitude Weighed Integrated Energy Spectra provides a more separable signature in responding to bed thickness changes than seismic signature. A lower degree of ambiguity of Amplitude Weighed Integrated Energy Spectra in sensing thin-bed seismic is a potential method of reducing thin bed interpretation uncertainty. Qualitatively, Amplitude Weighed Integrated Energy Spectra is capable of showing one of the reported very thin meandered channel complexes of gas reservoir of Stratton field which is difficult to be seen in seismic amplitude. In this research, Amplitude Weighed Integrated Energy Spectra is incorporated in a stochastic seismic inversion to improve both accuracy and precision (certainty) of thin-bed interpretation. The signature of Amplitude Weighed Integrated Energy Spectra is used to constrain the degree of match (likelihood) between seismic model and data. Synthetic data testing shows that the proposed method significantly improves both accuracy and precision of a single wedge model seismic inversion. The thickness and reflection coefficient are estimated more accurately, although limited information is used. The proposed method was tested to invert a structurally subtle gas production zone of Stratton field. Confirmed by well log data, a cross section of inverted impedance showed that some channel complex structure of gas reservoirs are able to be imaged.