Cumulative Drilling Depth
YEAR
Cumulative Drilling Depth
Cumulative Oil
Cumulative Gas
3.36 ϫ 10 9 m 3 (21.1 ϫ 10 9 bbl)
4.69 ϫ 10
12 m 3 (167 Tcf)
YEAR
0
0
0
50
100
150
Tcf
1950
60
70
80
90
1
2
3
4
20
40
60
80
100
0
5
10
15
20
10 9 m 3
10 12 m 3
10 9 bbl
1
2
3
1950
60
70
80
90
20
40
60
80
100 10
6 m
10 6 m
2.2 ϫ 10 9 bbl
discovered
32Tcf
discovered
Predicted Future
Past
A
B
Predicted Future
Past
Figure 7.4. (A, B) Example regression models for petroleum resource evaluation
(after Lee and Price, 1991). Dots represent reserves. The curve was derived by
regression analysis. (A) Recoverable oil reserves. (B) Marketable gas reserves. By
1990, a total of 2.2 Bbbls of oil and 32 Tcf of gas had been discovered. Data from
the Western Canada Sedimentary Basin.