Alberta Geological Survey

Oil Production from the Debolt/Elkton

Oil production from the Debolt/Elkton is primarily derived from the erosional unconformity in southeast Saskatchewan and south-central Alberta, as well as from the foothills disturbed belt in southern Alberta and northeast B.C. Scattered Debolt/Elkton oil production also occurs an southern Alberta, around the Peace River Arch and in northeast B.C. Included are fields producing from the Midale and Ratcliffe beds, Turner Valley and Debolt formations, and Stoddart Group.

There arc 19 Debolt/Elkton oil fields (13 in Saskatchewan, 5 in Alberta and 1 in B.C.) with Initial Established Recoverable Clil Reserves of over 1 x 10⁶m³ (6 MMBbls). The ten largest Debolt/Elkton oil fields, listed in order of Initial Established Recoverable Reserves, are shown in Table 1. Cumulative production data for Alberta and British Columbia are updated to the end of 1990 and for Saskatchewan to the end of 1989.

Table 1- Ten Largest Debolt/Elkton Oil Fields (in units of 10⁶m³)

Initial Established

No.	Field	Stratigraphic Unit	No. of Pools	Marketable Reserves	In-Place volume	Cumulative Production	Discovery Year
1	Weyburn	Midale	2	56.5	228.2	46.2	1954
2	Steelman	Midale	1	43.0	107.9	38.2	1954
3	Turner Valley	Rundle/TV	2	23.9	159.4	22.5	1922
5	Midale	Midale	1	21.1	76.8	17.5	1953
6	Harmattan East	Rundle/TV	2	12.7	33.4	11.0	1957
7	Harmattan-Elkn	Rundle/TV	2	12.0	30.0	10.3	1955
9	Caroline	Rundle/TV	3	9.3	26.8	8.3	1954
	Carnduff	Midale	1	5.2	15.2	4.6	1955
	Benson	Midale	1	3.5	19.9	2.4	1956
	Alameda	Midale	1	3.4	12.5	2.9	1956

Six of these fields occur along or immediately downdip of the unconformity developed on the Midale in southeast Saskatchewan. Caroline, Harmattan East and Hanmattan-Elkton occur in stratigraphic traps at the Elkton wedge edge. The Turner Valley field is in a structural trap in the foothills disturbed belt. Almost all of the Debolt/Elkton oil fields contain light to medium gravity oil.

Total recoverable oil reserves in the Debolt/Elkton are estimated at 220 x 10⁶m³, of which 184 x 10⁶m³ (i.e. 84%) have already bee produced. Initial Established In-Place Volume of Debolt/Elkton oil reserves totals 936 x 10⁶m³. There are 124 Debolt/Elkton oil pools, with average recoverable oil n serves of 1776 x 10³m³/pool. Table 2 lists the distribution of Debolt/Elkton oil reserves according to In-Place Pool Size.

Table 2 - Size Distribution of Debolt/Elkton Oil Pools (in units of 10⁶m³)

In-Place Pool Size Class	No. of Pools	Recoverable Reserves	Cumulative Production
less than 0.1	8	0.03	0.02
0.1 to 1	63	2.35	1.26
1.0 to 10	38	18.21	13.21
10.0 to 100	12	76.41	62.58
over 100	3	123.23	106.85
Total	124	220.24 x 106m3	183.91 x 106m3