3D Post-Stack Acoustic Impedance Inversion Results for Kijing and Malong Fields,South Natuna Sea

摘要

Post-stack acoustic impedance inversion was performed atKijing, Malong, and Buntal fields. The results allow detailedreservoir characterization of the fields to be done, and predictthe location of porous, reservoir-quality sands, and in manycases, reservoir-quality sands that contain gas. Several aspectsof the inversion results prove to be useful that cannot beachieved through the use of seismic analysis alone. Theremoval of wavelet effects (tuning, extra events due toconstructive wavelet sidelobe interference, and dimming dueto destructive wavelet sidelobe interference) is one importantenhancement. Seeing the impedances as layer propertiesinstead of as interfaces allows information about the sands andshales to be observed. Increase in bandwidth, both on the lowend with the introduction of a good low frequency model fromthe interpolation/extrapolation of well log impedance alonginterpreted horizons and the use of geologic constraints, andon the high end due to the use of a spectral whiteningdeconvolution operator and proper inversion parametersproduces increased resolution.The inversion results at Kijing, Malong, and Buntal fields maybe used to discern details about the reservoir sands, especiallyin conjunction with the current geologic and geophysicalinformation from conventional seismic data, well logs,analogs, etc. 3D visualization of the reservoir shows thestructure of the sands, most of which are channelized.