Figure 4 - Little Beaver Tertiary Air Injection Project.
(Encore Investor Presentation, 2006)

The Encore Acquisition Company's High Pressure Air Injection (HPAI) project at Little Beaver (Cedar Creek Anticline, U.S.A) was implemented as a tertiary process, i.e. after waterflood. The reservoir is a dolomite and contains 33 – 39 ^oAPI oil. The pool is situated on the crest of the anticline.

As shown in Figure 4, most of the injection and producing wells were both horizontal.

This project showed an early increase in oil production rate in response to air injection. Later, reservoir fractures near the crest of the anticline are believed to have caused channelling of the injected air and profile control issues in the laterals. There is a high probability that this problem could have been mitigated using wet combustion or cyclic air injection.