Integrated History Matching Process As Applied to the Tengiz Field

Travis C. Billiter¹, Steve Jenkins², Wayne Narr³, and Mark Skalinski^1
1TengizChevroil, Atyrau, Kazakhstan
²CABGOC, Luanda, Angola
³Chevron Energy Technology Co, San Ramon, CA

Fractured carbonates such as Tengiz are known to be difficult to history match. In tackling the history matching of the Tengiz simulation model, an integrated approach was taken by the Work Team. This approach provided for rapid feedback loops between engineer and earth scientists, throughout the upscaling and history matching process. This approach provided a final history matched model which balanced the needs of the earth scientists and engineers, and one that resulted in fewer simulation runs.
This updated model was a step change in reservoir characterization introducing new methods: APERM, (permeability from PLT), Petrophysical Rock Types, and use of Multipoint Point Statistics.
During the upscaling process, the Team approach was utilized with the engineers exploring different upscaling techniques, sharing the results, and receiving feedback from the earth scientists. The history matching process was started during the upscaling process and allowed the engineers to feed key information back to the earth scientists.
The next stage involved the transfer of fracture transmissibilities from the fracture model to the upscaled simulation model. The fracture specialist and engineer worked iteratively, both reviewing the history matching results. By working closely with the fracture specialist, the engineer was able to quickly capture in the history matched model a reasonable fracture representation.
During the final portion of the history matching approach, the Team agreed on geologic features in the model which reasonably could be adjusted. These guidelines allowed the engineer to proceed quickly towards a history matched model. By studying the dynamic data within the listed constraints, the engineer was able to provide key feedback to the earth scientists.

AAPG Search and Discovery Article #90072 © 2007 AAPG and AAPG European Region Conference, Athens, Greece