Murphy Oil Corp. said its subsidiary has drilled the Hai Su Vang-2X (HSV-2X) appraisal well in Block 15-2/17 in the Cuu Long basin, about 40 miles offshore Vietnam, strengthening the company’s view of the Hai Su Vang (Golden Sea Lion) discovery made in 2025. The well was spud in early October 2025 as part of Murphy’s appraisal campaign to delineate the field.
Murphy said the HSV-2X appraisal well encountered 429 ft of net oil pay across the same two reservoirs tested in the discovery, compared with approximately 370 ft of net pay reported in the initial Hai Su Vang discovery well. The appraisal included 332 ft of net oil pay in the deeper primary reservoir and 97 ft in a shallower reservoir.
Within the primary reservoir, Murphy said HSV-2X deepened the proven oil-down-to by 413 ft without encountering water, extending the total hydrocarbon column to about 1,600 ft. Formation evaluation supports reservoir continuity to the HSV-1X discovery well, the company said.
Flow testing of the primary reservoir produced 6,000 bopd, and Murphy said the well produced 37° API oil, consistent with results from the discovery well. The company said additional testing is ongoing.
Murphy said the results support an updated recoverable resource view for the field, with the midpoint estimate for the primary reservoir trending toward the high end of its previously communicated 170–430 MMboe range, and the new high end exceeding 430 MMboe. Murphy said results from the shallow reservoir add potential upside not included in the earlier range, but additional appraisal wells will be required to further refine recoverable resources in both reservoirs. The company plans to continue appraisal with HSV-3X in Block 15-1/05 and HSV-4X in Block 15-2/17, and reaffirmed 2026 capex guidance of $1.1–$1.3 billion.
