Murphy Oil confirms major find in Vietnam - potentially the biggest oil discovery in Southeast Asia of the last 20 years

Murphy Oil's successful appraisal of its Hai Su Vang (HSV) discovery in Vietnam's offshore Cuu Long Basin positions it as the largest oil find in Southeast Asia of the last two decades, according to Wood Mackenzie analysis. 

The HSV-2X appraisal well encountered 429 feet of oil across two reservoirs and tested at 6,000 barrels per day of 37° API oil. Murphy has revised its recoverable reserves estimate toward the upper end of the 170-430 million barrels of oil equivalent (mmboe) range previously announced, with additional shallow reservoir sections providing further upside potential. 

"In a predominantly gas-prone region, oil discoveries of this scale are exceptional," said Angus Rodger, head of Asia-Pacific upstream analysis for Wood Mackenzie. "HSV ranks as the third-largest oil discovery in Southeast Asia since 2000, trailing only Indonesia's Banyu Urip and Malaysia's Gumusut. Remarkably, Murphy has made two of the five largest oil finds since 2000 and was involved in the development of a third."

Wood Mackenzie now estimates Murphy’s Hai Su Vang to be the third largest oil discovery in Southeast Asia since 2000, and the largest oil find of the past two decades.  

Southeast Asia’s largest oil discoveries since 2000 

Source: Wood Mackenzie Lens 

Banyu Urip was discovered onshore Indonesia in 2001, and Gumusut in the deep waters of Malaysia in 2003. Interestingly, Murphy also discovered the Kikeh field off Malaysia in 2002, and was involved in the development of Gumusut, giving it a remarkable track record in Southeast Asia’s most recent big oil finds. 

A potential turning point for Vietnam 

The discovery offers Vietnam a chance to reverse a two-decade production decline. The country's oil output has fallen from 365,000 barrels per day in 2005 to below 120,000 b/d in 2025.  

The find also arrives at a critical moment for Vietnam's ongoing offshore licensing round, which includes Cuu Long Basin acreage. Confirmation of a discovery of this magnitude in a mature basin is expected to attract renewed exploration interest. 

However, Vietnam has been known for slow regulatory processes and a lack of data transparency, which has deterred potential investors and delayed new developments. Ccommercialisation speed will test Vietnam's recent regulatory reforms. "Positive changes to the petroleum law in 2023 and new leadership at the Ministry of Industry and Trade aim to improve investor confidence, but execution will be key," says Jasman Adam Leong, senior analyst at Wood Mackenzie. 

Murphy's Southeast Asia success story continues 

HSV marks Murphy's second major oil discovery in Southeast Asia, following its 2002 Kikeh find offshore Malaysia. The company sold its Malaysian portfolio to PTTEP in 2019 and has since pivoted to Vietnam, where it is also developing the Lac Da Vang field, due onstream later this year. 

Wood Mackenzie expects HSV to be developed as a standalone project using an FPSO linked to wellhead platforms. Murphy plans two additional appraisal wells through 2026 to further delineate the resource. 

The US explorer has now discovered over 1.4 billion boe of net resources in its Southeast Asia portfolio since 2002. 

Murphy’s largest operated discoveries 

Source: Wood Mackenzie Lens 

Regional exploration momentum builds 

HSV is the latest success in Southeast Asia's exploration renaissance and is great news for oil-focused exploration in the region, with other high-impact wells still to come in 2026e have identified three Asia-Pacific wells-to-watch over the next 12 months that are targeting material liquids targets.  

These include TotalEnergies' ultra-deepwater Maliu-1 in Papua New Guinea (targeting 500+ mmboe), Pertamina's Besar-1 offshore Indonesia (450 mmboe target), and TotalEnergies- Jampuk-1 in the ultra-deepwater of Malaysian Sabah. 

"Southeast Asia is proving that mature basins still hold significant potential when paired with modern exploration techniques and improved fiscal terms," added Rodger. "The challenge now is converting these discoveries into production that will require sustained commitment from both governments and operators."