Journal of Canadian Petroleum Technology, Vol.49, No.12, 19-27, 2010
Drilling Challenges in the Bitumen-Saturated Grosmont Formation
The Upper Devonian Grosmont formation, located in the West Athabasca oil sands deposit, contains an estimated 318 billion barrels of bitumen. The reservoir is a heavily karsted and fractured, bitumen-saturated dolomite with up to 38% porosity and permeabilities commonly measured in the darcies. These properties make the Grosmont an excellent candidate for steam assisted gravity drainage (SAGD). Grosmont SAGD development will be exposed to similar operating conditions as McMurray SAGD projects, and will have similar logistics, well construction and materials challenges. However, there are many additional challenges, including severe loss circulation, that further complicate well design. This paper presents the challenges experienced by Laricina Energy in drilling Grosmont wells at Saleski and Burnt Lakes over the last three seasons. It will also address additional areas for future research and development in the drilling of vertical and horizontal wells.