Gulf of Mexico deepwater discoveries survey shows lean year

By Bruce Beaubouef, Managing Editor  

The past twelve months have been a lean time for new oil and gas discoveries in the Gulf of Mexico, with only two publicly announced and a possible third. And one of those was offshore Mexico, an area not typically included in Offshore’s annual US Gulf of Mexico deepwater discovery survey. This contrasts significantly with the eight new discoveries in the deepwater Gulf of Mexico in 2023 but equals the three deepwater discoveries reported the year before. 

These numbers can be seen as a significant decline – or more in line with historical trends, depending on the comparison year. For example, if one reviews the numbers seen roughly 20 years ago, there were 12 discoveries announced in the deepwater GoM in 2004. That number contrasts starkly with the number of discoveries announced in 2024. But if one looks at the following year (2005), there were nine recorded discoveries – a number more in line with the number announced by industry in 2023 (eight discoveries).

Of course, the number of new discoveries can be driven by a range of factors, most notably oil price trends. Over the past 10 years, the industry has seen two oil price shocks (2014 and 2020); and more recently, a suspension of lease sales and a focus on renewable energy that has in turn led to lower levels of investment and drilling. 

One publicly announced discovery in 2024 was the Ewing Bank 953 well, operated by Walter Oil & Gas with partner Talos Energy, which encountered 127 ft of net pay in the target sand at 19,000 ft TVD. Early analysis suggests a recoverable resource range of 15 MMboe to 25 MMboe from a single subsea well. Current plans call for the well to be tied back to the Walter Oil & Gas-operated South Timbalier 311 Megalodon platform.

In addition, Talos Energy reported that it had contracted Transocean’s Deepwater Conqueror to complete its Sunspear discovery well, originally discovered in July 2023. This well will be connected to the Prince platform and should go online in 2Q 2025.

Reports have also indicated that Occidental Petroleum has made an oil discovery in the deepwater US Gulf of Mexico that is already being progressed towards a final investment decision. Little information was made available on this discovery.

Offshore Mexico, Eni has announced a potentially large oil and associated gas discovery in the Sureste basin. The Yopaat-1 EXP exploration well was drilled in 525 m of water (1,722.4 feet) in Block 9, some 63 km offshore in the Cuenca Salina, reaching a TD of 2,931 m. It delivered around 200 m net pay in hydrocarbon-bearing sands in the Pliocene and Miocene sequences. Eni estimates in-place resources of 300-400 MMboe.

The company operates the block under a 50-50 joint venture with Repsol. Yopaat, along with earlier Eni discoveries in Blocks 7 and 10 in the same basin (more than 1.3 Bboe combined), could form the basis for a future hub development, Eni added.

Other wells

Karoon Energy Ltd. has announced “promising” initial results from the Who Dat East exploration/appraisal well in Mississippi Canyon block 509 in approximately 3,200 feet of water. The company reported that the well intersected liquids-rich gas condensate in 45 m of “quality” net pay in a series of Miocene turbidite reservoirs. Karoon Energy says that intermediate logging confirmed the presence of “high-quality,” hydrocarbon-bearing sands in the upper target sections, with several deeper targets still to be drilled. The well has since been suspended as a potential future producer.

Elsewhere, LLOG says that all of the initial wells to support the Salamanca FPU have been successfully drilled and cased. This includes discovery wells drilled at Castile and Leon, with additional successful development wells drilled in 2023 and 2024. The final well finished drilling in September 2024 at the Leon Development (Keathley Canyon 686 #4), with better than expected results, encountering greater than 1,000 ft of high-quality oil-bearing sands, LLOG says. The facility will be located in Keathley Canyon 689 in about 6,400 ft of water. 

Upcoming drilling 

Talos Energy, one of the more active drillers in the Gulf of Mexico, announced last year that it would take delivery of Seadrill’s West Vela drillship for a three-well exploration program.

The vessel drilled the Katmai West #2 well in late September to further appraise the field and potentially add to the resource.

In 1Q 2025, the West Vela will drill a potentially high-impact Daenerys subsalt exploration well in the Walker Ridge area, targeting 100-300 MMboe in the Mid-Lower Miocene.

On completion the West Vela will likely drill Helms Deep, an amplitude-supported, near-infrastructure subsalt Pliocene prospect (17-27 MMboe) with a planned depth of round 18,000 ft.

Talos also acquired a 21.4% stake in the Monument discovery in the deepwater Wilcox play in the Walker Ridge area last year. Operator Beacon and its partners plan a subsea tieback to the Shenandoah production facility with an anticipated start-up of late 2026.

For more info, check out this year’s “Status of US Gulf of Mexico deepwater discoveries since 2000” in the tables below.