Patent ID: 7559368
Filing Date: 2009-07-14
Classification: C10G,E21B

Abstract:
1. A method for treating an oil shale formation comprising nahcolite, the method comprising: providing a first fluid to a portion of the formation through at least two injection wells; producing a second fluid from the portion through at least one injection well until at least two injection wells are interconnected such that fluid can flow between the two injection wells, wherein the second fluid includes at least some nahcolite dissolved in the first fluid, and wherein producing the second fluid from the portion causes selective vertical shifting of the portion such that the hydrocarbon richness of the portion that has been vertically shifted is increased; injecting the first fluid through one of the interconnected injection wells; producing the second fluid from at least one of the interconnected injection wells; providing heat from one or more heaters to the formation to heat the formation; and producing hydrocarbon fluids from the formation.