ONGC explores deepwater promise at BB-OS-DW-II

Vol 20, PW 4 (03 Nov 16) Exploration & Production
     

As pre-NELP blocks go ONGC's licence BB-OS-DW-II on the west coast is not one that immediately springs to mind as an obvious exploration play.

But excited about discoveries at nearby acreage, ONGC is gearing up for a Rs295cr ($44m) exploration programme beginning April 2017 to drill two wells: GBBDW-II-A and GBBDW-II-B-SH, located in water depths ranging from 189 to 210 metres. ONGC's renewed enthusiasm for BB-OS-DW-II, held since December 28, 1998 when it won the PEL, stems from a hugely significant gas discovery made in February this year (2016) at well MBS053NAA#1 which flowed 68,410 cm/d from two intervals at nearby block MB-OSN-2005/3 that ONGC (70%) and Essar (30%) share.

"This was the first discovery ever made beyond the (continental) shelf margin and also in the Pliocene formation in the Mumbai offshore basin," says an ONGC submission to the environment ministry on September 12. "Clearance (for drilling) is being pursued with the help of the DGH from the Ministry of Defence and is expected any moment." Until now a lack of deepwater rigs and defence ministry refusal to grant drilling permission have blocked ONGC plans.

Adding to ONGC's excitement is discovery well SR-01-A1-ST1 at nearby exploration block SR-OS-94/1 once operated by Reliance but since relinquished but which, "has shown the presence of biogenic gas in a shallow Plio-Pleistocene interval marked by high amplitude reflections at a shallow level (800m)."