| 摘要 |
A method for enhancing production from multiple-fractured underground “tight” formations. Spaced upwardly-extending injection fissures are created along a horizontal injection wellbore, and upwardly-extending collection fissures, alternately spaced with the injection fissures, are created along the horizontal injection wellbore or another adjacent production wellbore. The injection wellbore is supplied with fluid under pressure, which flows into such created fissures and drives reservoir fluids within the formation to the remaining (alternately) spaced adjacent fissures along such wellbore or another parallel adjacent (production) wellbore, thereby allowing reservoir fluids to flow downwardly along such alternately spaced production fissures for collection. In a refinement, production is carried out initially from both the production and injection wellbores, and upon the rate of production of hydrocarbons slowing, production from the injection wellbore is stopped and a fluid is injected therein and thus into the formation via the alternate spaced fissures, thereby re-pressurizing the formation. |
| 主权项 |
1. A process for recovering hydrocarbons from a subterranean formation utilizing hydraulic fractures which become injection and production channels within said formation, comprising the steps of:
(i) drilling an injection well having a vertical portion and a horizontal portion extending horizontally outwardly from a lower end of said vertical portion; (ii) drilling a production well having a vertical portion and a horizontal portion extending outwardly from a lower end of said vertical portion, wherein said horizontal portion of said production well is situated parallel to said horizontal portion of said injection well; (iii) fracturing the formation along each of said production well and injection well and creating a plurality of upwardly-extending fissures extending upwardly from, and situated along a length of, said horizontal portion of each of said injection well and said production well, said upwardly-extending fissures created along said injection well mutually alternating along said horizontal length thereof with upwardly-extending fractures situated along said production well; (iv) injecting a pressurized fluid into said injection well and thereby into said fissures above said injection well and thence into said formation thereby pressurizing said formation and causing said hydrocarbons within said formation to be driven into said fissures above said production well, and to drain downwardly therein into said horizontal portion of said production well; and (v) producing said hydrocarbons which collect in said horizontal portion of said production well to surface. |
