原生水饱和度（connate water saturation）的概念是啥？ [复制链接]

原生水饱和度（connate water saturation）是指什么饱和度啊？原始含水饱和度么？啊

油藏中的流体从运移到聚集经历了漫长的地质年代后，达到一种过平衡状态，按密度的不同进行分离。除了底水和边水外，储层中由于毛管力的作用，孔隙中还分布着最低限度的原生水。最低限度的原生水通常呈水膜状附着在岩石的孔隙周围，通常也称之为束缚水饱和度。
而原始含水包含束缚水，可能还有共生的边底水。

看来我们的论坛大有高人。学习了！

也感兴趣于这个话题。但不甚明了。想继续问：

什么是原生水？什么是共生水？

虽然通常认为原生水饱和度和束缚水饱和度相等，但从概念上讲，它们是不是仍有区别呢？

In formation evaluation for petroleum, connate saturation is lowest water saturation found in situ, while irreducible saturation applies to the lowest water saturation achievable in a core sample by displacing the water with oil or gas using a centrifuge or other device

懂了，谢谢楼主

原生水：在地质时期已经存在于储层中的水。           共生水：是指任何与油藏相伴生的水。

Petroleum literature contains several symbols for water saturation; Swi, Swc, Swir.
Care must be taken to ensure correct interpretation of the symbol. The following definitions should help.
1) Swir -irreducible water saturation, below which water cannot flow.
2) Swc -connate water saturation existing on discovery of the reservoir. It may or may not be irreducible. Be careful!
3) Swi -may mean irreducible, connate, or interstitial, which means saturation among the interstices, or pores. Interstitial may or may not signify irreducible. It may be the value on discovery of the reservoir, or the value at any time thereafter. Swi may also mean initial or original, which truly means the water saturation on discovery, but it may or may not be irreducible.

懂了，谢谢二楼大虾了