注水开发过程中变差函数的变化及孔隙度变化规律

不同微相的孔隙度在开发过程中的变化规律是不一样的。丛聚型河道中,开发初中期孔隙度分布明显受单河道的大小和形状控制,注水开发过程使得粘土矿物被带走,并消除了河道之间的高含泥屏障,致使开发后期孔隙度的次变程加大,平面上的分布更趋广泛,但纵向上非均质性加剧。对离散型河道而言,由于孔隙度的高值区仅分布于离散的河道内,注水过程并不能改变河道的形状,因此,尽管河道侧缘的储层性质有所改观,平面上孔隙度的分布基本不受注水开发的影响。

THE CHANGE OF THE VARIOGRAM FUNCTION AND THE VARYING RULE OF THE POROSITY IN THE COURSE OF WATER FLOODING

The variation of the porosity in different microfacies during the development of hydrocarbon is different.In the clustered channel facies,the distribution of porosity is controlled obviously by the width and shape of the single channel during the early production stage.The perpendicular variogram range of the porosity during the later production stage becomes greater,the distribution of the porosity becomes wider and more even,and the vertical heterogeneity becomes more intensive,because the clay minerals between grains were taken away by the fluids in water flooding performance,and the high mud content barrier between channels were removed by the fluids.In the dispersed channels,the high porosity was distributed in the center of the dirpersed channels,and the shape of the channel cannot be changed by the fluids of the water flood process,therefore,the distribution of the porosity is essentially not influenced by the water flood process,even though the properties of the flanks of channels can be changed in some extent..