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This paper was selected for presentation by an SPE Prcgram Committee fdlcwing reviaw LX information contained in an abstract submitted by the author(s). Contenk of the paper, as presented, have not been reviewad by theSocLetj cd Petroleum Engineers and are subject to cow+ztion by the author(s). The material, as presented, does not necessarily reflect any position of the Society C4 Peboleum Engineers, iks dfims, or members. Papers presented at SPE meetings are subject to publication review by Edtiorial Committees cd the Society d Petrcleum Engineem Electronic reprcdution, distribution, or storage of any part d this papar for ccxnmercial purposes without the written consent C4the Society d Petroleum Engineers is pmhitited, Permission to reproduce in print is restricted to an abstract d not more than X0 work, illustrations may not be copied. The abstract must contain conspicuous acknmvledgment d where and by whom the papar was presented. Write Librarian, SPE, PO. Box 833436, Richardscm, TX 75083-3836, U. S. A., fax 01-972-952-9435. AbstractThee major new technologies developed in the past decade in the heavy oil regions of Alberta and Saskatchewan are long, shallow horizontal wells, &eam-Assisted @avity Drainage (SAGD), and cold lkoduction (C?). These three technologies are briefly reviewed. They can be combined in a geneml approach to heavy oil reservoir development that will give the advantages of reasonable early oil production rates, continued long-term production, and excellent long-term recovew. A combination of vertical wells and horizontal wells are used to achieve early CP, which is then gradually replaced by long-term SAGD production. As the processes progress, vertical CP wells will decline in production rate; when they are no longer economical to produce, these wells are converted to other purposes. They can Ix used as inert gas injectors, control wells, low-rate thermal injection or production wells, or even sand disposal wells, as long as they help maintain the reservoir at the appropriate pressure for SAGD. The proper balance of pressures through injection or production to maintain the long-term stability of processes in the gravitydorninated flow regime is critical to SAGD success.Given price fluctuations and long-term projections, economic factors related to heavy oil must be addressed. It is appropriate to point out that within 10-15 years, the current conditions of low prices and over-supply of conventional crude oil will be replaced by a world-wide shortfall in oil supply, which should bring a permanent increase in oil prices..

The technology of multiple hydraulic fracture stimulation in horizontal wells has transformed the business of oil and gas exploitation from extremely tight, unconventional hydrocarbon bearing rock formations. The fracture stimulation process typically involves placing multiple fractures stage-by-stage along the horizontal well using diverse well completion technologies. The effective design of such massive fracture stimulation requires an understanding of how multiple hydraulic fractures would grow and interact with each other in heterogeneous formations. This is especially challenging as the interaction of these fractures are subject to the dynamic process of subsurface geomechanical stress changes induced by the fracture treatment itself. This paper consists of two parts. Firstly, an idealised analytical model is used to highlight some key features of multiple hydraulic fractures interaction, and to provide a quantification of 'stress shadow'. Secondly, a new non-planar three dimensional (3D) hydraulic fracturing numerical model is used to provide an insight into the growth of multiple fractures under the influence of subsurface geomechanical stress shadows. Attention is given to studying the height growth of multiple fractures.

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