Well test interpretation

[Umair.Shafeeq]

Can anybody tell me about phase redistribution during build up of a well test?
How can we get k and s from distorted data in this region?
I am using KAPPA Ecrin for WT analysis.
pic is not being uploaded..
A sharp hump is observed at the start of build up. Gauge P becomes above the Res P.

Regards,
Umair Shafeeq
Reservoir Engineer
ENI Pakistan

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

[zaheer.jamali]

send me pics into my mail
zaheer.jamali@live.com

[alouche]

Umair,

These pressure humps are the results of the phase redistribution effect. The reservoir fluid is light compressible oil (or gas). As the pressure build up start, the compressible reservoir fluid and the less compressible mud filtrate is redistributed within the isolated zone and the tool internal volume. This process generates an extra pressure. Although the pressure hump effect on the pressure build-up data is significant (how much is the drawdown pressure during pumping? ). The pressure build up almost reaches the reservoir pressure . The hump effect causes the recorded pressure to exceed the reservoir pressure and it takes certain time to reach the pressure equilibrium. The decreasing pressure buildup destroys the diagnostic feature of the pressure derivative .
Can you share the data for more details? is this MDT or RCI ?
email: nounounig(at)gmail.com

Regards
Alouche

[brhm]

You can not estimate the permeability from this derivative plot. if you have another data you can try to put your straight line to get kh value...

[gmwambler]

Umair

do you have production history for this well?
if yes then can you share it on gmwambler@yahoo.com
because this distorted data could mislead you, if you have production history including rate variations you can directly run deconvolution after extract P and get results.

you can share data on gmwambler@yahoo.com
regards,
Salman

[indianoilman]

You can not estimate the permeability from this derivative plot. if you have another data you can try to put your straight line to get kh value...

There are methods available...
you can simulate the whole process using variable wellbore storage models available now a days and can estimate reservoir properties. Try latest PanSystem software. it has some inbuilt methods to do that.