濮城油田沙三中层序格架内储层非均质性研究

对濮城油田沙三中油藏的研究表明,基准面旋回控制了砂体展布及储层的非均质性特征.在短期基准面上升期,形成向上物性变差、高渗段位于砂层下部的层内非均质模式;而在短期基准面下降期,形成向上物性变好、高渗段位于中上部的层内非均质模式.在中长期基准面较低位置处,砂体厚度大、分布面积广,沟道相对较为发育,物性相对较好;而在中长期基准面较高位置处,砂体厚度薄、面积小,沟道不发育,储层物性较差.在中长期基准面上升旋回内形成向上物性变差的层间非均质格局,而在中长期下降期则形成向上物性变好的非均质性格局.在水下扇前缘区,靠近湖心区其剖面上砂体中的沟道成分减小,砂体连通性和连续性及物性变差;而向岸方向则砂体相对较连续,物性较好.

Reservoir heterogeneity analysis in the base level frame of Pucheng Oilfield

The base level cycle controlled sand distribution and the reservoir heterogeneities in Pucheng oil reservoir.In the rising period of short cycle,the reservoir heterogeneity model with better property at the bottom of the sandstone and poorer to top,as well as with a totally different way in the falling semi_cycle.It was reversed in the lowering period of short cycle.At the lower position of medium and long term cycles,braided channels with a wide spread area and good property were well developed,while the braided channels were small,and the sand spread area was limited with poor property at the high position of the cycles.In the rising semi_cycle of long_and medium_cycles,the reservoir became poorer from bottom to top,while it became better in the falling semi_cycle.From the bank to lacustrine center,the braided channel became weaker and smaller,and the reservoir architecture turned from mainly channel sands near the middle fan to mainly sheet_like sands near the front of middle fan,and finally turned to lacustrine mud in the lake center.