A Methodology of Underbalanced Drilling Design in Depleted Reservoir

When overbalanced drilling is done in depleted reservoir, lost circulation occurs and cause formation damaged.<br>Underbalanced drilling (UBD) is proposed to be done to prevent lost circulation and increases production due to minimizes<br>formation damaged. Besides, as formation being drilled underbalanced, it is possible to produce hydrocarbons from permeable<br>zones, therefore earlier benefit could be acquired by company as producing phase began.