Abstract

Early in 1986, the first commercial gas pool in the British Columbia Deep Basin was discovered at Noel, when several metres of gas pay were encountered in the Cadotte Member in the Canhunter Noel d-15-D/93-P-8 well. Subsequent development drilling and coring have provided sufficient data to interpret the depositional history of the Cadotte in the Noel area.

Two cores illustrate the two primary depositional sequences. One from the Noel d-15-D/93-P-8 well represents a progradational sequence that coarsens upward from fine grained, low-energy shoreface sandstones through interbedded poorly sorted sandstones and conglomerates of the high-energy shoreface to better-sorted conglomerates deposited on the foreshore. In contrast, the core from the Noel b-28-C/93-P-8 well illustrates an incised channel sequence cutting into low-energy shoreface sandstones, and consists of a basal mud-clast and conglomerate lag, fining upward to poorly sorted sandstones. When all the well control data are considered, a major southwest-northeast paleovalley system can be mapped, incising the regional east-west Cadotte shoreline trend.

Other examples of valley incision during deposition of the Cadotte Member have been found in outcrop and the subsurface, and provide abundant evidence of a lowering of base level in late Cadotte time as the result of a relative sea-level fall.