不同覆压条件下储层物性变化特征及水驱油实验研究

Experimental Study of Reservoir Physical Property Change and Water Flooding under Different Overburden Pressures

在油田注水开发过程中,地层中流体静态平衡被打破,岩石储层在上覆地层压力作用下发生形变,从而改变岩石的物性特征,进而影响水驱采收率。以王龙庄油田、绥中油田取心井岩心为实验样品,开展了不同围压下的岩石物性测定及水驱油实验,结果表明:岩石孔隙度、渗透率与围压呈幂函数关系,且随着围压的增加,岩石孔隙度、渗透率逐渐减小;水驱油效率与围压呈指数函数关系,并确定了不同指数的分布范围。

In oilfield water flooding,due to the breaking of formation hydrostatic balance,reservoir rock deforms under the overburden pressure,changing its physical properties and thereby affecting its water flooding recovery.An experiment,with the core of coring wells in Wanglongzhuang oilfield and Suizhong oilfield as samples,was carried out to measure the petrophysical property and water flooding under different confining pressures.The results show that rock porosity and permeability are of power function relationship to confining pressure,decreasing with the increase of confining pressure,while oil displacement efficiency of water flooding is of exponential function relationship to confining pressure,determining the distribution range of different exponents.