Abstract

The Sparky Formation of the Lower Cretaceous Mannville Group is the major oil producing formation in the Lloydminster heavy oil area (Twp 44-52, Rge. 25-28W3,1-7W4). The depositional environment has not been well understood although several depositional models have been suggested in the past. This paper briefly reviews the literature and stratigraphy of the Sparky Formation and proposes a depositional model based upon extensive geophysical log and core studies in the area. The cores selected are from the Aberfeldy, Blackfoot and Wainwright fields.

The Sparky Formation in the Lloydminster area is interpreted to be a northeastward prograding, wave-dominated deltaic system. Shale-filled channels developed in this deltaic system commonly act as an important trapping mechanism; sand-filled channels locally form potentially thick reservoirs. The thick sand reservoirs are probably related to tidal inlet deposition.