engleski

Reservoir Characterization of the Stari Gradac Gas Condensate Field Using Seismic Attributes

Analysis of seismic attributes was applied to the seismic reflection survey of the Stari Gradac gas condensate field. The Stari Gradac reservoirs are located at a depth exceeding 3, 400 m, in high temperature and pressure conditions. The complex structure and lithologic diversity also contribute to the uniqueness of the reservoir. During the investigation and development phase several reinterpretations of the geological model and reservoir relations were made in accordance with available data and program packages. In this paper, a reinterpretation of the lithologic boundaries which define the reservoir was carried out. For the purpose of their reliable identification on the seismic cross-sections, one-dimensional modeling was used (synthetic seismogram). The results of one dimensional modeling on the Stari Gradac field indicated solutions which better defined the boundaries of the lithofacies than the earlier interpretations. The shallowest clastic lithofacies in the reservoir was interpreted as a uniform unit, whereas the position of the top of the dolomite lithofacies was also corrected, according to the synthetic seismogram. Seismic trace attributes were calculated from the seismic trace presented in the complex form, which separated the amplitude information from the phase and frequency information. Fundamental attributes improved the accuracy of interpretation and confirmed the synthetic seismogram results. In the selected time intervals statistical seismic attributes were calculated along the seismic horizons. A simultaneous analysis of different statistical attributes showed changes in individual lithologic units of the reservoir, such as changes in thickness and compactness as well as changes in saturation.

Hilbert transform; seismic attributes; seismic reflection; synthetic seismogram; Stari Gradac field

nije evidentirano