drainage area and well spacing

[sharpjiy]

Dear all

I'd like to ask something regarding well drainage area and spacing.
I understood that well drainage area is time dependent.
(The oil is more produced, the well drainge area larger when there is no physical boundary or do not contact with other producing well drainage area)

when we calculate EUR by each well, we might be need to reservoir area for each well.
if we have producing well which have a well testing data and want to use these data for other wells which not drilled, how can we do?
(drainage area isn't static value.... in my opinion)

I imagine we can calculate drainage area after Well spacing,
But someguys say that well drainage area used for well spacing.
which one is first?

Does anybody show me an example which build well spacing plan with only a few producing wells?

Best regards,
sharpjiy

[sundarraman.s]

well drainage depends upon a lot of things. like Permeability of the reservoir (heterogeneity of the reservoir - lithologically), drive mechanism, API gravity of oil. If the permeablity of the reservoir is on the higher side then its better to space out your wells rather than drilling wells close to one another and ending up with the production interference. Also in case of water drive reservoirs its generally better to optimise you well spacing so that the oil production doesnt leave too much of left out oil due to coning in between two producers.
And yes well spacing is generally calculated from well test data. and well spacing can be different in a single reservoir depending upon the heterogeneity of the same.
Well spacing studies need to done on priority while generating a Field Development Plan with the help of well test data available and the geological model to optimize ultimate recovery of any oil / gas field, and data from any new well drilled should be used to update your geological model and simulate the same. Such studies help a lot while planning Water injectors / gas injectors and suitable positions for oil producers.

Hope it helped .