Using special core analysis in reservoir engineering
The extensive use of reservoir simulation in the evaluation, development and management of oil fields is placing increased importance on the correct use of results from special core analysis, particularly those from relative permeability tests.
Correct use of these data requires knowledge of the history of the core, including the drilling mud used during coring as well as how it was handled on its way to and in the laboratory. As a consequence the course covers such topics as coring operations and core preservation techniques. Laboratory measurement methods are also addressed, since results are affected by the techniques used and the test conditions.
Results that are considered valid require adjustment and refinement, and an understanding of laboratory techniques is needed to do this, since each method has its own strengths and weaknesses. The reasons why steady-state and unsteady-state waterflood results are often different is explained in this way. There is emphasis throughout the course on identifying invalid or questionable data and making the necessary refinements to the data which are considered to be valid.
A comprehensive manual accompanies the course which includes numerous examples from the North Sea and elsewhere in the world.
- On completion of the course, participants should be able to:
- carry out a systematic review of a laboratory report and differentiate results that are clearly invalid from those that may be reliable,
- define the strengths and weaknesses of the various laboratory measurement techniques and identify which portions of reported relative permeability curves are likely to require refinement,
- analyse and evaluate reported relative permeability curves and make necessary adjustments and refinements,
- relate relative permeability results to rock types,
- formulate a special core analysis programme for a new well or field.
Who should attend?
The course is designed primarily for reservoir engineers involved with reservoir simulation and/or classical hand calculations, but will also be of great value to supervisors and managers who review simulation results carried out by others.
Laboratory personnel involved with SCAL measurements will find the course useful in learning how their results are used and in gaining insight into how laboratory programmes might be improved. Production geologists and petrophysicists working in integrated teams will also find the course valuable, particularly in selecting samples for analysis and assisting in relating relative permeability and capillary pressure to rock type.
While lectures form the foundation of the course, exercises will be used through computer workshops to improve understanding and allow the participants to gain hands-on experience.
These illustrate the techniques and refinements that are often required when using a set of water-oil relative permeability results from an intermediate wettability reservoir. Such techniques can be used not only to analyse raw laboratory data, but also to assess the reliability of relative permeability relationships used in existing reservoir simulation models.
Other exercises will deal with (a) estimating true residual oil saturation from flooding results and (b) characterising plugs used in special core analysis tests.
Although the principal course focus is on the use of relative permeability data, the use of primary drainage capillary pressure data to define the distribution of connate water saturation is also covered.
The course is 3 days in length and can be presented as an in-company course tailored to your company’s requirements.
Comments from past participants
"I will say that the instructor and the material of this course are excellent. I gain a lot of knowledge from this course."
"Excellent understanding of work undertaken and would recommend."
"Excellent for understanding oil-water and gas-oil perm relationships. Course overall is extremely useful."