84
Statistical Methods for Estimating Petroleum Resources
and/or depreciation in resource assessment results vary for different
estimators. The results from the Jumping Pound example indicate that
(1) the effect of reserve appreciation or depreciation on the estimation
of play resource distribution is minimal, as shown in the comparison
of play resource distributions for a specifi c time window (fi gs. 4.15B,
4.17B, and 4.18B); and (2) the expected potential decreases consistently
as the amount of discovered resources increases—that is, the resources
of the time windows are similar in each play.
200000
100000
50000
In-Place Pool Size 10 6
m 3
10000
5000
1000
0
5
1 0
Pool Sizes by Rank, 5th to 95 Percentile
Quirk Creek Rundle A
Clearwater Rundle A
15
20
Figure 4.16. Pool-size-by-rank plot derived from a pre-1966 time window of the
Jumping Pound Rundle gas play (Fig. 4.15). Note that the Clearwater Rundle A
and Quirk Creek Rundle A pools were predicted.
Table 4.5. Summary of the Retrospective Study, Jumping Pound Gas Play
Time window Total no.
of pools
estimated
Discovered
resource at
time window
Expected
potential
Play resource at
0.9 probability
prediction interval
Expected
resource
Pre-1966
100
208
213
279–525
382
Pre-1974
100
262
63
183–730
376
Pre-1991
173
355
28
210–630
366