Gates, IanEdafiaga, Benjamin2022-09-202022-09-202022-09Edafiaga, B. (2022). The application of fishbone wells in steam-assisted gravity drainage (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.http://hdl.handle.net/1880/115242Apart from cost, major challenges facing the recovery of bitumen from Canadian oil sands are the amount of energy utilized per volume of bitumen recovered as well as the amount of greenhouse gas (GHG) emitted to the environment. The situation is even worse in reservoirs that are considered to be challenging or difficult-to-produce due to the reservoir geology. Steam-assisted gravity drainage (SAGD) is the primary in-situ recovery technique for bitumen recovery in Northern Alberta, Western Canada. Within the reservoir, steam chamber conformance is a major control on the efficiency, economic performance, and GHG emissions intensity of the process. There is a search for ways to significantly reduce the costs and emissions of SAGD. Multilateral wells possess the potential to contribute towards this goal. To date, different theoretical designs of multilateral wells have been proposed in literature. One of the most common designs studied is the fishbone well configuration. This configuration has large reservoir contact and thus enhances the productivity of the well. While the merits of the application of multilateral wells are well documented in lighter oil systems, an understanding of the best operating conditions for the use in oil sands reservoirs is poorly understood. The research documented in this thesis examines in detail how fishbone multilateral wells can be used to improve the performance of SAGD. In summary, the results demonstrate that fishbone well are able to improve steam chamber conformance and ultimately minimize cumulative steam-oil ratio (cSOR), maximize ultimate bitumen recovery, improve net present value (NPV), and reduce GHG emissions. Therefore, fishbone multilateral wells should be considered for future SAGD operations.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Steam-Assisted Gravity Drainage (SAGD)Cumulative Steam Oil Ratio (cSOR)Green House Gas (GHG)Net Present Value (NPV)Engineering--Petroleumdoctoral thesis