1. MICP – typical data on small samples
Clay destruction/texture alteration
pore volume increases during the test
distorted Pc curves

2. MICP curves - then

3. MICP curves - now
Same reservoir formation – different vintages and equipment and different sample size

4. Irreducible water saturation, Swirr

5. New core acquisition What core analysis tests do we need?
don’t pick tests from a menu
review legacy data for uncertainties & gaps
Is the contractor interpretation correct?
“raw” data needed to check and verify
Can operators improve on the lab interpretation?
“end users must not abdicate their responsibility for the interpretation of core data”

6. Planning for core analysis
Well operations
core bit, mud, tracers, preservation
core handling and stabilisation
Stage analysis program
to suit business needs
flexibility in-built

7. Improved project management
Project team
The lab is part of the team!
Single operator focal point
Real time quality control
Improved documentation
test specifications & reporting
invaluable in unitisation
Key Personnel
Drillers/well operations
Wellsite geologists
Mud engineers
Company geologists
Company petrophysicists
Coring company
Core analysis vendor
D&C, reservoir engineers and petrophysicists all have different and often conflicting demands for core data.
Job of the focal point is to liaise with the stakeholders and the lab and that there is a single point of contact, and to promote a much more pro-active and integrated approach.

8. Improved core analysis management
Better core
Coherent and consistent core analysis
Added value
data redundancy less than 10%
Labs more involved and aligned with stakeholder objectives
Full data audit trail
better equity and unitisation positions
Less uncertainty in reservoir models
Price is what you pay. Value is what you get - Warren Buffet

9. Core Analysis: A Guide to Maximising Added Value
Questions & discussion
Colin McPhee
Senergy (GB) Limited
Society of Petroleum Engineers Distinguished Lecturer Program

10. Back Up Slides

11. Porous plate Pc Semi-permeable membrane Loss of capillary contact
capillary contact medium
Loss of capillary contact
air/oil enters porous plate or contact medium before sample fully desaturates
Non-equilibrium saturation
plate permeability is low
brine relative permeability low
drainage through plate is slow

12. Porous plate Pc Semi-permeable membrane Loss of capillary contact
500
Underestimate OIP in Sw-height models
Semi-permeable membrane
capillary contact medium
Loss of capillary contact
air/oil enters porous plate or contact medium before sample fully desaturates
Non-equilibrium saturation
plate permeability is low
brine relative permeability low
drainage through plate is slow
400
Air-water capillary pressure (psi)
200
100
Water Saturation (v/v)
0.2
0.8
1.0

13. Formation factor (F) and ‘m’

14. Resistivity index (I) and ‘n’

15. MICP – sample damage Clay destruction/texture alteration
pore volume increases during the test
distorted Pc curves

16. SPE August 2010

17. Example plug history sheet
Emphasise details not so important, it can be easily adapted but it presents all data you need to evaluate data and to ensure full audit trail is available for each SCAL plug