Reservoir Volume estimation method

How are reserve volumes estimated and how often do they change througout a fields life?
A basic introduction is very welcome, more details aswell...

thanks!

The process of estimating oil and gas reserves for a producing field generally continues throughout the life of the field. There is always uncertainty in making such estimates. The level of uncertainty is affected by the following factors:

1. Reservoir type,
2. Source of reservoir energy,
3. Assumptions adopted when making the estimate,
4. Available technology, and
5. Quantity and quality of the geological, engineering, and geophysical data,
6. Experience and knowledge of the evaluator.

All these factors need to be re-assessed as new data comes in during the life a of a field.
Therefore, the magnitude of uncertainty decreases with time until the economic limit is reached and the ultimate recovery is realized.

hope this helped

Reservoir estimation method will be hot topic in 2014ICRSM, the commitee collected estimation methods from relative reservoir experts, managers and consult for decades, the suitable solutions will be benifit oilfields and relative operators.