鄂尔多斯盆地合水地区长8油层组非均质性研究

 从层间非均质性、层内非均质性和平面非均质性3方面对鄂尔多斯合水地区长8油层组非均质性进行了研究。研究区长81油层组和长82油层组砂体频率和砂体密度相近，层间渗透率非均质性较弱，层间隔层厚度变化较大，整体上长8油层组层间非均质性较弱；研究区长81、长82夹层发育，存在多段高渗层，层内渗透率的变异系数、突进系数和级差都较大，两油层段的层内非均质性均较强；研究区长81、长82流动单元分布受沉积微相的影响明显，差、中流动单元分布较多，好流动单元分布较少。

Heterogeneity of Chang 8 Member in Heshui Area,Ordos Basin

The heterogeneity of Chang 8 Member in Heshui Area in Ordos Basin is studied from the aspects of interlayer heterogeneity, intralayer heterogeneity and plane heterogeneity. The distribution of sandbodies is similar in both Chang 81 and Chang 82. The heterogeneity of interlayer permeability is weak. The thickness of barrier beds between Chang 81 and Chang 82 is quite changeable. The interlayer heterogeneity is weak as a whole. The barrier beds in Chang 81 and Chang 82 are well developed, with several highly-permeable beds. The variation coefficient, the rush coefficient and the differentials of intralayer permeability are large, and the intralayer heterogeneity is strong. The distribution of flow units in Chang 81 and Chang 82 in the studied area is mainly controlled by microfacies. There are more bad and intermediate flow units and less good ones. The good ones are mostly located in submarine distributary channel microfacies and mouth bar microfacies. The intermediate and bad ones are mostly located in distal bar and distributary interchannel microfacies. The heterogeneity of reservoirs is one of the most important factors to control the distribution of oil and water in the studied area. The heterogeneity of reservoirs has a pivotal effect on the distribution of remaining oil, and has a crucial effect on the oilfield development. Developing plans should be made and adjusted based on the reservoir heterogeneity.