SAGD oil recovery method utilizing multi-lateral production wells and/or common flow direction

摘要

Improved SAGD methods for recovering heavy oil from underground formations. In a first aspect a method is provided for drilling, using multi-lateral drilling techniques, a series of horizontal collector wells from a vertical shaft of a production well, below and parallel to an injection well. In a further alternative to the typical SAGD configuration having injector and producer well drilled from the same end of a region under development, the production well is instead drilled at an end of a region of development opposite to an end of such region at which an injector well is drilled. Lastly, in yet another aspect, the invention comprises a method for rejuvenating an existing SAGD well pair, comprising drilling a further production well or wells at an opposite end of said formation at which an existing injector well was drilled, preferably using multi-lateral drilling techniques.