Uncertainty configuration

[Sjat]

Dear senior RE,

I am junior RE, I just finished capture uncertain parameters in my reservoir model. I did static and dynamic model by myself. Condition : There are 7 flow units clastic rock, undersaturated, no natural fracture, and mature field.

During static modeling phase, I generate 3 Facies model ( consist of 4 rock type), 2 Porosity/permeability each facies model, 3 groups of OWC (P90, P50, P10). these uncertain parameters could give me range of oil in place.

I have 15 years production history. limited on rates and several points of BHP from PLT. Now, in dynamic model I have 2 additional uncertain parameter. SWCR and SOR. I have Sor data from SCAL, it ranges from 0.56 to 0.2 . to meet oil cumulative field production in simulation case, I must adjust Swcr and Sor depend on OWC (example : in P90 OWC I must choose higher Swcr & lower Sor).

so, there are 5 uncertain parameters.
1. Facies Model (3 realizations)
2. Oil Water Contact (3 realizations)
3. Poro/Permeability (2x @ facies realizations)
4. Swcr (depand on OWC)
5. Sor (depand on OWC)

now please advice me what should I do to quantify my most likely case, before I do manual history matching.

Many thank...

Sjat

[vinomarky]

So you are asking for guidance on selecting a 'most likely case' before embarking on the process which should reveal what the most likely case is???

Just start with what YOU think is most likely, explore sensitivities and go from there. If you want a bit more structure, try looking up some guides/papers on experimental design, which basically step you through a more structured way to assess and characterise range of outputs for a range of inputs to not only help get your history match, but to better understand the uncertainty in it.

[Sjat]

Thank vinomarky,

yes, I just read from a paper about that, your answer is exactly same. But, I still confuse with my dependent parameter, which is also depend on uncertainty parameter too (Sor depend on OWC to meet historical Oil cum). can I group these parameter into single Variable (let says, it called Z variable consist of group Z1,Z2,Z3...e) ?

now, I need experimental design spread sheet or software, do you have one ?

[vinomarky]

If you can create a relationship of (for example) Sor as a function of OWC, then its easy. When you have a moderate degree of linkage only it becomes more difficult, and you will just have to think through what makes most sense for your situation.

I do not have any sheet to calculate appropriate pairings to most efficiently calculate a response surface for a given number of simulation runs - I've seen many different tables though that for a desired number of runs suggest optimal parings to gain most information - those papers should be a good start, otherwise I think the likes of JMP can help. I normally use the package EnABLE to do it all in the background automatically for me.