Abstract:

Determination of suitable mud weights for the wells in the Hai Thach (HT-P) field is a very challenging task because of the high pore pressure and high temperature (HPHT) conditions. The main objective of this study is to determine a suitable mud weight for drilling into the HPHT zone of HT-P well. First, a thermo-chemo-pore-elastic model for calculating the stress around the wellbore is presented. Two failure criteria, Drucker-Prager and Mohr-Coulomb, are used and compared. Then, the determination of model inputs from well logs and available data is summarized. Finally, the numerical results of the model are analyzed to propose a new mud weight for the HPHT zone of HT-P well. The field data, modeling work and the proposed mud weight presented in this study can be used as a reference for drilling new wells in the Hai Thach field to avoid any wellbore instability problems.