ONGC targets Mumbai High UBD by September
Following on from its successful three-well underbalanced drilling programme at the Heera field earlier this year, ONGC now wants to use the production-boosting technique at its Mumbai High North field.
"We have begun preparing for a campaign by mid-September," confirms a senior consultant associated with the project. Halliburton and Baker Hughes carried out the underbalanced pilot at Heera.
But a Baker Hughes source when contacted said ONGC is yet to finalise any company. "They have tentative plans to drill four wells at Mumbai High North," he confirms.
ONGC will be targeting the prolific L-III layer in the main multi-layered limestone oil reservoir at an average TVD of 1300 metres. In underbalanced drilling the pressure in the wellbore is kept lower than the formation pressure.
Mumbai High pressure is at 1400-psi so the wellbore pressure will be kept at 1200-psi. Mumbai-based Askara Enterprises is coordinating the campaign on behalf of ONGC's Houston-based underbalanced drilling consultant Blade Energy.