Working Practices in Reservoir Study Teams

Good liaison and teamwork amongst the various disciplines is key to a successful study.


Client Liaison

  • What is the overall agreed timeframe for the project?
  • Does any work need to be completed before the geological modelling can begin? e. g. merging of log curves, data loading
  • Are software licences available and who is responsible?
  • Keep the client informed of progress and any significant problems.
  • However, do not overload the client with unnecessary details.
  • Does the client already have a ”result that must achieved”?
  • Avoid jumping to conclusions before the bulk of the work has been started.
  • Avoid giving out results before routine checks on the numbers have been made.
  • On the other hand do not wait until the end of the project for a peer review.
 

 

deterministic models using the same seismic envelope

Data

Go back to the original data sources where possible. Eliminate errors in manipulation of the data and sense the reliability of the data. Some data may be rejected as unreliable.

Remember that what a team member thinks is “data” and what is “interpretation” varies according to their viewpoint, discipline and the quality of data acquisition.

For instance a geophysicist will make a seismic interpretation and depth conversion of the reservoir horizon. This will be provided to the reservoir modeller as “input data”. Another example: layer formation pressures are used in different ways by different disciplines.

The Use of Multiple Models

Multiple models of the reservoir can be built in order to give a range of outcomes to the project. These deterministic models are built according to a particular geological idea about the sub-surface.

Geological Methodology for input into Dynamic Reservoir Modelling

Initially, minimise the number of steps to create the static model. It is possible that a simple model is adequate, such as in some gas reservoirs. The key parameters can be studied further so that the model can be refined to honour the dynamic data. Complex models using all possible workflow steps and data subdivisions (e.g. facies) do not guarantee a valid dynamic model.

When refining the model, it is usually more valid to try global changes before local changes. Keep track of model versions. The first model provided to the reservoir engineer should be a good attempt, but it will not be the final version. Avoid using the term “base case” until sensitivities have been examined.

 
 
       
KM Geoscience Ltd