000			02608nab a2200205 4500
005			20260520002020.0
008			260224s2011 xxu
245	0	0	_aOn SAGD in oil sands reservoirs with no caprock and top water zone
260			_a _b _cmar. 2011
270			_a07/09/2011 ; 07/09/2011
300			_a10 p. ; 21-33
520			_aTranscripción del resumen del autor. The ever-increasing world demand for energy to satisfy current needs and future economic growth has forced the oil and gas industry to exploit challenging energy resources. Heavy oil and oil sands are challenging because of the complexity of reservoirs together with high-oil viscosities, which are often greater than hundreds of thousands to millions of centipoise. Most steam-based recovery processes, such as cyclic steam stimulation (CSS) and steam-assisted gravity drainage (SAGD), require a competent caprock to prevent excessive steam losses and maintain good thermal efficiency and production rates, as well as preventing steam flow to surface. However, there exist significant amounts of oil sands resources, which have little or no caprock; thus, at this point, these resources are considered inaccessible. This research examines the feasibility of using SAGD in oil sands reservoirs with no caprock with detailed thermal reservoir simulation. The results of this research provide guidelines that explain how to implement the SAGD process in shallow oil sands reservoirs with no caprock. This could unlock a resource that is currently considered inaccessible. The results show that vertical chamber growth can be controlled to some extent by using variable pressure operating strategies and coinjection of a noncondensable gas, such as methane. In oil sands reservoirs without caprocks, pressure control is critical, especially if there is to be minimal fluid invasion from the oil sands formation into the water zone above. However, the pressure must be sufficient to delay or prevent flow of water into the steam chamber. This study is important because in Alberta, Canada alone there are billions of barrels of shallow oil sands resources without sufficient caprock to operate conventional high-pressure steam recovery processes, such as CSS and SAGD. The results of the study provide a technical basis to design feasible low-pressure steam processes for such reservoirs.
581			_a3
773	0		_tJournal of Canadian Petroleum Technology _g50
942			_cARTICULO
100	1		_aAl-Turki, Ali A. _951467
100	1		_aGates, Ian D. _938702
100	1		_aMaini, Brij B. _99552
999			_c185437 _d185437