Fault
Facies Modelling - a Practical Approach to Incorporating 3D
Fault
Architecture in Standard Reservoir Models
Jan Tveranger, Alvar Braathen, Nestor Cardozo, Magne Espedal, Niclas Fredman,
et al.
Center for Intergrated Petroleum Research (CIPR), University of Bergen, Bergen, Norway
Present methods for including faults in reservoir simulation models largely disregard the fact that fault
impact in reservoirs is commonly not limited to a single, clear-cut
fault
plane but affects a volume of host rock, thereby creating a complex 3D architecture significantly influencing fluid flow. By failing to incorporate the presence of often extensive
fault
damage zones and
fault
core architectures into the reservoir model: -actual 3D flow inside and through
fault
zones is not captured -in-place volumes are overestimated -
fault
sealing (including capillary seals) is highly simplified -communication along faults can not be forecast -model uncertainty cannot be properly evaluated as
fault
features critical for reservoir behaviour are not included in the model -hazardous areas for drilling can not be reliably predicted
The Fault
Facies project has developed a practical methodology that allows volumetric gridding of
fault
zones on reservoir scale models and populating the resulting
fault
envelopes with realistic
fault
architectural elements and petrophysical properties. Models are built using a standard reservoir modelling tool (Irap RMS) employing a customised gridding algorithm in HAVANA. Architecture and petrophysical properties of the
fault
zones are modelled by adapting facies model tools developed for object based modelling of sedimentary facies and employing volumetric strain as a conditioning parameter for the resulting
fault
zone architecture and petrophysical properties. The new method is fully integrated with existing modelling workflows and offers a practical solution to evaluation of
fault
impact on reservoir fluid flow in realistic detail.
AAPG Search and Discovery Article #90072 © 2007 AAPG and AAPG European Region Conference, Athens, Greece