Publications

Shallow Zone reservoir of Tunu Field (TSZ) which was initially identified as drilling hazards, has now been extensively developed since 2009 with more than 600 Bscf of cumulative gas. The zone consists of widespread and scattered gas-bearing sand reservoirs, with strong aquifer drive mechanism. Today, more than 280 development wells have been drilled, and as the field is aging up, there are more than 62% wells have been died or idle. As an impact from driving mechanism, most of idle wells are related to water influx from reservoir to wellbore. These wells have been studied and revival program is performed by considering the strong aquifer support and reservoir re-equilibrium process in the reservoir. Based on trial phase that have been conducted, global strategy to revive the dead well have been developed, in order to optimize remaining reserves and also to support field production target. To implement this initiative, several supporting items were prepared: well candidate selection workflow, static condition requirement by dynamic well simulation, automatic monitoring tool for well candidate selection based on static condition requirement, campaign categories, job preparation (i.e. dedicated deltaic swamp testing barge), and regular monitoring & evaluation. Continuous implementation from this initiative has given additional production gain and recovered volume significantly to support field production target. Guidance from this best practice could give an initiative idea for other gas field with typical characteristics for optimizing each standard cubic feet of gas volume from existing idle wells.