升平油田葡萄花油层高分辨率层序地层格架及储层特征

利用高分辨率层序地层理论分析方法,在升平油田葡萄花油层三维地震资料及15口井岩心和356口井测井资料综合研究的基础上,通过不同级次基准面旋回界面特征的识别,将本区划分为1个长期、2个中期、6个短期和13个超短期层序,以超短期层序为目标,建立了单砂体等时对比单元的地层格架。以超短期层序为控制目标,详细研究了葡萄花油层沉积微相及单砂体分布规律:基准面上升期是三角洲河道砂体发育最有利时期,单砂体厚度大连续分布广;湖泛期细粒沉积物分布广泛,储集层不发育;基准面下降期受下切作用影响,河道砂体不发育。提出了葡萄花油层超短期旋回层序由于同沉积构造抬升作用所导致的从北到南逐渐减薄超覆尖灭新地层模式。

High Resolution Sequence Stratigraphic Framework and Reservoir Characteristics of Putaohua Reservoir in Shengping Oilfield

According to the three-dimensional seismic,15 well cores,and 356 well logging data,by using the high-resolution sequence stratigraphy theory,the authors identified the cycle surfaces of Putaohua reservoir at different time base level cycle in Shengping oilfield.The stratigraphy is divided into one long-term,two medium-term,six short-term and 13 super short-term cyclic sequences.The high resolution sequence stratigraphic framework has been established by taking the super short-term cycle sequence as the isochronous stratigraphic correlation unit in the region.The gradually southward thinning and missing stratigraphic model has been proposed in Putaohua super short-term base level cycle sequence,which was resulted from the tectonic uplift.The main sand distribution of Putaohua reservoir has been clarified through the research on the characteristics of single sand body distribution in the super short-term base level cycle.It is indicated that the continuous stacking thick sandbodies developed at the ascending hemicycle in the delta channel and the fine-grained sediments deposited at the descending hemicycle represent the main development stage of regional restraining barrier and cap rock. Based on the above analysis and application of the high-resolution sequence stratigraphy,the isopach map of sandstone,the ratio of sandstone to mudstone,the sedimentary microfacies map,and 3-D simulation of sequence indicator of sandbody distribution are plotted in a chronological stratigraphic framework.