production profile- reservoir model and well decline profile in excel.

[Chee Koh Peh]

Unfortunately this is more than meets the eye, particularly if the Gas Condensate reservoir is a retrograde reservoir and you are looking to model condensate production in the retrograde (liquid drop out) region. Well decline is a function of many parameters however is mainly influenced by: (1) reservoir drive mechanism, (2) relative permeability effects, (3) reservoir permeability, (4) well spacing and (5) well timing etc...

You get the drift here, it is unfortunately not straight forward particularly in the case of gas condensate reservoirs, however what you can do is look to a similar fields known as "analogues" that have similar reservoir and geological properties, see what the historical well declines are there and use those declines in your cashflow model. Importantly this gives you a "defensible" answer as to why you selected the well declines etc... you did.

Know this is probably not the answer you are looking for, but condensate reservoirs particularly retrograde condensate reservoirs are tricky.

[dumdum01]

Unfortunately this is more than meets the eye, particularly if the Gas Condensate reservoir is a retrograde reservoir and you are looking to model condensate production in the retrograde (liquid drop out) region. Well decline is a function of many parameters however is mainly influenced by: (1) reservoir drive mechanism, (2) relative permeability effects, (3) reservoir permeability, (4) well spacing and (5) well timing etc...

You get the drift here, it is unfortunately not straight forward particularly in the case of gas condensate reservoirs, however what you can do is look to a similar fields known as "analogues" that have similar reservoir and geological properties, see what the historical well declines are there and use those declines in your cashflow model. Importantly this gives you a "defensible" answer as to why you selected the well declines etc... you did.

Know this is probably not the answer you are looking for, but condensate reservoirs particularly retrograde condensate reservoirs are tricky.

Hi Thanks for the reply. Would it make it easier if it was just a gas reservoir.? It is primarily a gas reservoirs I am looking at with some associated condensate production. I have just downloaded the reservoir engineering handbook and using the volumetric method for gas reservoirs. There seems to be a lot of variables to calculate Gas in Place. I am wondering if some of these can be taken as constant based on analogues?

How do RE colleages do it if they have no prior information about a reservoir and only geological information.

Thanks again for your help.
Adi.