Strachan-Ricinus Gas Field, Alberta: ABSTRACT

Abstract

Exploration for reef reservoirs in the Deep Basin of Alberta during the mid-60s resulted in the discovery of 1.9 Tcf of sales gas, 50 million bbl of condensate, and 24.5 million LT of sulfur in two reefs of Late Devonian age, at Strachan and Ricinus. The reefs were discovered in 1967 and 1969, respectively, by adapting the seismic CDP techniques of data acquisition and processing that were then being developed (particularly in the Rainbow area, in the shallower part of the Western Canada sedimentary basin). The key well for these discoveries was the Gulf-Strachan well in Lsd. 12-31-37-9 W5M, which was drilled in 1955. This well encountered a partial buildup of Upper Devonian reef which yielded some gas and salt water End_Page 469------------------------------ from a depth of 13,900 ft (4,237 m). CDP seismic data were acquired and, after considerable experimentation in processing with orientation to the appropriate geologic model, showed that the key well was on the flank of what is now called the Strachan reef. In 1968, Banff and Aquitaine drilled a full reef buildup of 900 ft (27 m) in Lsd. 10-31-37-9 W5M with a pay section of 540 ft (165 m). A separate pool, the Ricinus reef, was discovered in 1969 by Banff and Aquitaine in Lsd. 6-25-36-10-W5M. The well showed a reef buildup of 800 ft (245 m) and a maximum pay of 690 ft (210 m). Remaining reserves of marketable natural gas at Strachan and Ricinus, after 6 years of production, are approximately 1 Tcf. End_of_Article - Last_Page 470------------