用较高活度的页岩样品置于不同低活度的盐溶液上方,测定其吸附等温线,发现溶液活度越低页岩脱水越甚。测定页岩在不同溶液中的线膨胀量。当溶液活度降低到一定值时,页岩开始发生收缩,一段时间后收缩页岩重新膨胀,收缩量随溶液活度降低而增大。证实了活度平衡理论在水基流体中成立,但渗透压是一种动力学现象,具有瞬时特征。最后讨论了毛细管效应不是导致页岩膨胀的主要因素。 Shale samples with higher activity were placed on top of salt solutions with different activities. The adsorption isotherms were determined. The lower the activity, the more shale dehydration. Determination of shale in different solutions in the amount of linear expansion. When the solution activity decreases to a certain value, the shale begins to shrink. After a period of time, the shrinkage shale re-expands. The amount of shrinkage increases with decreasing solution activity. It is confirmed that the activity equilibrium theory is established in water-based fluids, but the osmotic pressure is a kind of dynamical phenomenon with instantaneous characteristics. Finally, it is discussed that the capillary effect is not the main factor leading to the shale expansion.