OWC and FWL

[guizadosis]

Hi everyone,
Something that I can't understand really is how it can be that for oil wet reservoir the FWL is above the OWC
can someone explain it?

[DAH7542]

In a capillary tube, water-wetting surface forces cause water to rise (thus OWC above FWL) displacing oil, but if the tube inner surface is oil-wetting, the oil will push water down (thus OWC below FWL).

Read this: "Fundamentals of Wettability " by Schlumberger. Download from:

[link Point to another website Only the registered members can access]

[DAH7542]

In a capillary tube, water-wetting surface forces cause water to rise (thus OWC above FWL) displacing oil, but if the tube inner surface is oil-wetting, the oil will push water down (thus OWC below FWL).

Read this: "Fundamentals of Wettability " by Schlumberger. Download from:

[link Point to another website Only the registered members can access]

[guizadosis]

thanks DAH but this in a capillary tube, how it can happen really in a reservoir

[DAH7542]

Pore throat network in porous rocks are physically describe as capillary tubes. The physics are the same. Take a look at the paper "Fundamentals of Wettability " by Schlumberger and you'll get an idea of these physical principles.

[temr]

To speak shortly
FWL- is the level from you model you PC curve
OWC - is the level where you get pure water and can cave some oil there but in in movable condition
The diff is FWL is almost cases is lower than OWC
but there reservoirs where FWL is higher than OWC

[temr]

To speak shortly
FWL- is the level from you model you PC curve
OWC - is the level where you get pure water and can cave some oil there but in in movable condition
The diff is FWL is almost cases is lower than OWC
but there reservoirs where FWL is higher than OWC

[guizadosis]

do you mean that the FWL doesn't exist in reality it's fictif concept

[DAH7542]

The FWL does exist. In fact, the common approach of using RFT/MDT data to determined the intersection of, let's say for example, the oil and water gradients yields the position of the FWL, not the OWC as commonly believed.