| The Lower Cambrian Longwangmiao intra-platform shoal reservoirs are thin in Ziyang area in Sichuan Basin and they get pinching out due to denudation toward the northwest of Ziyang area. It is the key how to effectively identify the distribution of high-quality reservoirs. According to Well ZY-1 and 3D seismic data, some reservoir prediction technologies are adopted such as seismic facies, conventional and frequency-divided seismic attributes, ancient landform and fracture prediction on the basis of fine calibration and interpretation of reservoir horizons. Firstly, seismic facies and the conventional attribute are used to characterize sedimentary facies belt. Secondly, the frequency-divided attribute coupling with inversion is used to determine the boundary and thickness of the reservoirs. Finally, ancient landform and fracture prediction are used to determine the spacial distribution of high-quality reservoirs. It is shown that Longwangmiao reservoirs mainly develop in the middle and upper parts in longitude, and distribute in two NE-towards intra-platform shoal bodies in lateral. The northwest part of study area is just located in the pre-Permian palaeostructure high parts where exposed denudation area is likely to form dissolved pore dolostone reservoirs which is convinced to be the area favorable for hydrocarbon migration and accumulation. |
