Alberta Geological Survey

Gas Production from the Woodbend Group

Gas production from the Woodbend Group is primarily derived from D-3 reefs in south-central Alberta and especially occurs as solution gas in D-3 oil pools. There are 35 Woodbend gas fields with Initial Established Marketable Gas Reserves of over 1000 x 10⁶m³ (35 BCF). The ten largest Woodbend gas fields, listed in order of Initial Established Marketable gas reserves, are shown in Table 1. Cumulative production data are updated for Alberta to the end of 1990.

Table 1 - Ten Largest Woodbend Gas fields (in units of 10⁶m³)

Initial Established

No.	Field	Formation	No. of Pools	Marketable Reserves	In-place Volume	Cumulative Production	Discovery Year
1	Westerose South	Leduc	1	39,200	52,407	38,938	1953
2	Strachan	Leduc	3	29,369	44,364	25,891	1967
3	Ricinus West	Leduc	1	24,500	49,756	21,545	1969
4	Homeglen-Rimbey	Leduc sol'n	2	24,499	33,296	24,158	1952
5	Bonnie Glen	Leduc sol'n	2	18,858	31,964	6,558	1951
6	Leduc-Woodbend	Leduc sol'n	6	11,778	18,111	5,329	1947
7	Liege	Grosmont	11	9,179	16,746	4,936	1974
8	Windfall	Leduc sol'n	7	9,067	29,136	6,635	1955
9	Wimborne	Leduc sol'n	1	8,006	14,443	5,349	1954
10	Westerose	Leduc sol'n	1	6,166	8,815	3,123	1952

The largest field, Westerose South, occurs along the Rimbey-Meadowbrook Reef Trend, and the Strachan and Ricinus West fields are located in the deeper foothills of south-central Alberta. Six of the remaining seven largest Woodbend gas fields occur as solution gas associated with major Woodbend oil fields in south-central Alberta. The Liege gas field is the largest of a string of Grosmont gas fields along the Woodbend wedge edge in northeastern Alberta.

Total recoverable gas reserves in the Woodbend Group are estimated at 265.3 x 10⁹m³, of which 188.9 x 10⁹m³ (i.e. 71%) have already been produced. Initial Established In-Place Volume of Woodbend gas reserves totals 522.9 x 10⁹m³. There are a total of 243 Woodbend gas pools, with an average 1092 x 10⁶m³ recoverable gas reserves/pool. Table 2 lists the distribution of Woodbend gas reserves according to In-Place Pool Size.

Table 2 - Size Distribution of Woodbend Gas Pools (in units of 10⁶m³)

In-Place Pool Size Class	No. of Pools	Recoverable Reserves	Cumulative Production
1.0 to 10	20	60	22
10 to 100	78	1,896	586
100 to 1000	92	18,913	7,389
1000 to 10000	41	69,822	37,914
over 10000	12	174,616	142,976
Total	243	265,307 x 106m3	188,887 x 106m3