Popis: |
Analyses of lost circulation and wellbore strengthening require knowledge of formation and wellbore geomechanics. This chapter provides a brief overview of some geomechanical concepts related to the subject, including in-situ stress, pore pressure, wellbore stress concertation, wellbore failure criteria, and drilling mud weight window. A variety of field injectivity tests for determining in-situ stress and fracture properties (e.g. fracture initiation, propagation, and closure pressures) are also discussed. |