APPLICATION OF SEISMIC ATTRIBUTE ANALYSIS TO THE PERMIAN-TRIASSIC DEPOSITS IN THE SOUTH YELLOW SEA

Sedimentary facies analysis in the South Yellow Sea Basin was made in this paper based on seismic amplitude, phase and frequency, plus logging data. The old procedure did not take the full advantage of seismic attributes, although seismic attributes contain a lot of information of sedimentary facies. There are little well data existing in the South Yellow Sea Basin up to date. Therefore, it becomes a necessity to make full use of seismic attributes information for facies analysis of the Lower Triassic Qinglong Formation and the Permian Longtan-Dalong Formations in the South Yellow Sea. Our results show that there occur some relatively sensitive seismic attributes including arc length, average energy, energy half time, correlation length, average SNR and thickness. The arc length is a proxy to indicate the distribution of sand and mud, the average energy reflect the water energy or sediment dynamics at the time of deposition, energy half time is related to the continuity of facie distribution, correlation length and average SNR indicate the lateral continuity and seismic quality, and the thickness reflects the residual thickness of the target layers. Based on the analysis, we concluded that the platform facies of oolitic limestone is the most optimum reservoir in the Lower Triassic Qinglong Formation. The deltaic facies is the most optimum reservoir in the upper Permian Longtan and Dalong Formations, and the fluvial facies is also favorable.