| 摘要 |
A method of micro-fracturing in a well bore to define the stress field and fracture system for the purpose of optimizing subsequent hydraulic fracturing well completion operations. During or subsequent to drilling of the well bore, a down hole imager takes measurements that allow the operator to select appropriate zones of the well bore for optional micro-fracture testing. The micro-fracturing testing is conducted by stopping the flow of drilling mud and expanding one, or preferably two packers incorporated into a micro-fracture module of the drill string. The pressure in the isolated zone between the packers (or below the packer if one packer is used) is pressurized until fracture occurs. The trend in the pressure in the isolated zone of the bore hole is measured during the test to assess information about the fracturing of the bore hole. After micro-fracture testing, or upon completion of the drilling, the same zone of the bore hole is again scanned by the imager and the natural beak-outs or pre- and post-micro-fracture testing images are analyzed to ascertain further information about the formation. Micro-fracture testing is repeated over different zones of the well bore as the drilling proceeds or subsequent to the drilling operation and the information from these tests is used to optimize the major fracturing in the completion phase of the drilling. |
