基于精细三维地质模型的储层非均质表征方法探讨

APPROACH TO THE 3-D DETAILED GEOLOGICAL MODEL-BASED RESERVIOR HETEROGENEITY CHARACTERIZATION METHOD

储层非均质性研究是油藏描述的重要内容,传统的表征参数是基于少量离散观测值(井点)的统计。文章根据地质建模成果并结合地质规律,对曙光油田杜229区块兴隆台油组储层非均质性进行的研究表明:兴隆台油组层间非均质性严重,属不均匀型。兴I—兴V组储层为近源扇三角洲沉积,平面上由于河道摆动频繁,相变快,层与层之间渗透率差异性大;其中分流河口坝砂体非均质性最弱,分流间薄层砂微相最强。兴VI组为水下重力流沉积,岩性变化大,层间渗透率差异明显,非均质性更强。兴VI组辫状水道相非均质性最弱,水道间薄层砂微相非均质性最严重。隔夹层分布受沉积相带控制,在冲积扇分流河道内、边滩及心滩内等部位较发育,纵向上,隔夹层分布不均一,上部各油层组之间夹层分布相对稳定。

The reservoir heterogeneity research is the key for reservoir description and the traditional characteristic parameter is derived from the statistics of sparsely discrete observation points （wells）. Combined with the geological regularity the writer attempt to use results of the refined geological modeling and make detail researches on the reservoir heterogeneity of XingLongTai oil group block of Du 229 in ShuGuang oil field in three （horizontal, intra layer and interlayer） aspects in this paper. Data obtained show that the reservoir in XingLongTai oil group is seriously heterogeneous belonging to the heterogene ous type. The reservoir of I-V oil groups is proximal fan delta deposition. In plan channel of the river swings frequently and the sedimentary facies change abruptly with quite different permeability among layers. The reservoir heterogeneity of distributary mouth bar is the weakest, and the strongest for thin sand layer micro-facies of the distributary. Oil group VI is deposited by sub-water gravity flow and lithology is quite diversified and permeability among layers changes greatly and the reservoir heterogeneity stronger. The heterogeneity of braided channel is the weakest, and strongest for thin sand layer micro-facies among channels. The distribution of interlayer and oil-resisting layer are controlled by sedimentary facies and the interlayer is relatively developed in distributaries of the alluvial fan and in the central and side flood plains. The distribution of inter layer is heterogeneous vertically and is relatively stable in the upper part.