Page 169 - Enhanced Oil Recovery in Shale and Tight Reservoirs

Water injection 153

Figure 7.1 Comparison of water imbibition in matrix and fractured matrix (Lin et al.,
2016).

imbibition rate should be higher. Their lower imbibition rate might
result from other causes, for example, the core permeability might be
reduced after the earlier imbibition. Now we review some of waterflooding
field projects.

7.2.1 Waterflooding in Bakken and Lower Shaunavon,
Saskatchewan
Waterflooding projects have been performed by Crescent Point Energy in
its Bakken and Lower Shaunavon resources since 2006. Totally five patterns
in the Bakken and three patterns in the Lower Shaunavon were sanctioned
before 2011. For those trials, the first one in Bakken had a peak oil rate of
550 bbl/d from 50 to 100 bbl/d for four produces. The second pattern had
less increase in oil rate. It was too early to see the responses for rest of the
patterns by 2011. The injection patterns were such that horizontal injectors
paralleled horizontal producers with their spacings of hundreds meters
(Wood and Milne, 2011). Later a simulation study was conducted for a
Lower Shaunavon of one injector and 18 producers. The pilot production
and injection history were matched. At the end of history match, the recov-
ery factor was 1.4%. After 50 years, the recovery factor was predicted to be