Présentations Colloques

The study area is focused in Sukowati field, Bojonegoro Regency, East Java Basin. The geology formation is consisted by very thick claystone and characterized by many drilling events. Pore pressure prediction is very essential to reduce drilling uncertainty, determine safe and efficient mud window to prevent a blowout. One of pore pressure cases that often occurred was overpressure. People traditionally use a pressure diagram against depth to predict an overpressure phenomenon. A method that used to predict pore pressure in this research area is Eaton quantitative estimation.**Further analysis shows that overpressure in the research area is mostly affected by disequilibrium compaction which is explained by sedimentation rate. This mechanism is existed in Mundu Formation. Moreover, this study also noticed the possibility of clay diagenesis which played a role to generate overpressure that explained by geothermal gradient and cross-plot between log sonic against density.**