1,623 metres deep, an 11-metre gas pay zone, three days of continuous flaring: ONGC's third strike in the same 23-nautical-mile corridor off Konark.
NEW DELHI: Oil and Natural Gas Corporation Limited disclosed a deepwater natural gas discovery in the Mahanadi Offshore Basin to stock exchanges on September 21, 2026, marking the maiden exploratory success under the government’s “Samudra Manthan” national offshore exploration campaign. The well, designated MN-DW18-1-H-D, struck gas-bearing reservoirs on September 18 after reaching a total depth of 1,623 metres, with the primary pay zone identified between 1,441 and 1,452 metres, an 11-metre gas interval.
Drill-stem testing confirmed the find over a three-day period, during which ONGC reported continuous flaring and sustained, encouraging reservoir pressure. The well sits approximately 43 kilometres off the coast of Konark, Odisha, in water depths between 765 and 770 metres, drilled by the dynamically positioned drillship Platinum Explorer, which had spudded the well on July 25 following a formal launch by Union Minister of Petroleum and Natural Gas Hardeep Singh Puri.
A Third Strike Along the Same Corridor
Notably, this is not ONGC’s first success in this particular stretch of seabed. The well extends a play fairway already validated by two earlier discoveries in the same OALP block, MN-DWHP-2018/1. The Utkal discovery, made in August 2023 at roughly 714 metres water depth, was the basin’s first deepwater find under the Open Acreage Licensing Policy regime, while the Konark discovery followed in 2024 at 1,110 metres, confirming the lateral spread of gas-bearing channel sandstones. By striking gas roughly 23 nautical miles from the Konark find, ONGC has demonstrated that the shallow Pliocene turbidite channel system carrying hydrocarbons extends across a meaningful distance, a result that meaningfully reduces geological risk across the surrounding acreage and strengthens the case for developing the discoveries as a shared cluster rather than isolated standalone fields.
ONGC has been exploring the Mahanadi Basin since 2006, though deepwater drilling here has historically faced high costs and the technical challenge of imaging thin turbidite sand bodies. Compared with the Krishna-Godavari Basin, ONGC’s other major eastern offshore province, Mahanadi’s shallower reservoirs carry lower mechanical drilling risk and potentially lower completion costs, even as the KG basin continues to contend with high-pressure, high-temperature conditions.
The Policy Machinery Behind the Well
This discovery arrives as the first deepwater success tied directly to Samudra Manthan, the National Offshore Exploration Scheme approved by the Union Cabinet on July 31, 2026 with an outlay of ₹84,084 crore aimed at de-risking India’s unappraised offshore basins through extensive seismic surveys and drilling incentives. ONGC has separately committed ₹1 lakh crore in offshore capital expenditure over five years, targeting 87 exploratory and appraisal wells by FY31.
The commercial terms governing the block matter here too. Under the Hydrocarbon Exploration and Licensing Policy, which replaced the older cost-recovery production sharing model, ONGC retains full pricing and marketing freedom for gas produced from the block. New deepwater gas qualifies for “New Well Gas” pricing, and ONGC reported realising $13.31 per mmBtu for such gas in the first quarter of FY27, nearly double the $7.00 per mmBtu ceiling under the older Administered Price Mechanism for nomination gas. Separately, the Petroleum and Natural Gas Rules, 2025 now permit operators to pool adjacent offshore discoveries and share processing platforms and subsea pipelines across block boundaries, a mechanism that could make smaller, otherwise uneconomical gas pools viable when developed together.
What Still Needs to Happen
However, a discovery is not a producing field, and ONGC has released no volumetric estimates, meaning no Gas-Initially-In-Place figures, no certified 2P reserves and no projected daily flow rates. The path to commercial gas involves several distinct regulatory and technical stages. ONGC has planned a four-well appraisal campaign to delineate the field’s true boundaries, after which it must file a formal Declaration of Commerciality with the Directorate General of Hydrocarbons, typically within 18 to 60 months of discovery under standard HELP timelines. A Field Development Plan follows within 12 to 18 months of that declaration, before the company’s board can take a Final Investment Decision. From there, the engineering and construction phase, covering subsea trees, flowlines and platform installation, typically runs another 36 to 48 months before first gas actually flows.
Given the well’s relative proximity to shore, ONGC could plausibly tie subsea flowlines from Utkal, Konark and MN-DW18-1-H-D into a shared gathering hub, feeding a roughly 43-kilometre trunk pipeline to an onshore terminal on the Odisha coast, before connecting into the wider Dhamra-Kakinada pipeline network. That said, deepwater development carries real execution risk. Individual appraisal and exploratory wells in this class of water depth can cost between $50 million and $100 million each, and eastern offshore reservoirs have a history of complications, including sand production and unexpected water ingress, that could affect recoverable volumes or delay timelines.
What Comes Next
Whether MN-DW18-1-H-D becomes a genuine addition to India’s gas supply, or remains a promising but ultimately marginal find, will depend on the outcome of ONGC’s upcoming appraisal drilling and the eventual reserve certification that follows. For now, the discovery gives ONGC a second validated deepwater gas province on India’s eastern margin, alongside continued questions about volumetric scale, development architecture and whether the company brings in international technical partners, as it has done previously with bp on the Mumbai High redevelopment, to execute the Mahanadi cluster.
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