Thanks for that Petro, a few questions
Given that the P10 figures from GLJ and GCA only differ by 14.5% (11.8 versus 10.3), but
- There is a 50% gap in P50 numbers
- There is a much bigger difference in range (P10-P90) in GCA compared to GLJ; 57% versus 140%
Does that not indicate that:
- Much greater uncertainty on the part of GCA
- But at least some of that greater uncertainty comes from the fact that they had one reef well (the others are rounding errors) to work with
- Does the similarity in P10 figures not indicate that they have roughly the same seismic interpretation and work from similar geological models?
- Would it not be reasonable to assume that including Ant3 data into a future GCA appraisal would impact more on the P90 and P50 numbers, as it reduces uncertainty about how much of the seismics and geological model can deemed to have been demonstrated by actual well data?
It seems to me that the big difference in P90 and P50, but much less so in P10 numbers indicate that GCA roughly agrees with GJL about what seismics and the geological model show could be there, they are just much less certain about it, and to at least some degree that is because they had two, not three wells to work with.
Additional info for reference:
- GLJ: low case (P90): 7.53Tcfe; high case (P10): 11.8Tcfe; a difference of 4.3Tcf or just 57%
- Gaffney Cline: low case (P90): 4.3Tcfe; high case (P10) 10.3Tcfe, a difference of 6Tcfe or 140%
Let's also keep in mind that the payout from the certification is based on P50 numbers. If we did that today, we would have 8.25Tcfe (the average from GCA and GLJ, even excluding Ant3 from GCA).
Thanks.