No ‘immediate commercialization’ in sight for gas discovery offshore Japan

June 12, 2026, by Melisa Cavcic

Japan Petroleum Exploration Co., Ltd. (JAPEX) has shed light on its exploratory drilling activities in the offshore Hidaka area of Hokkaido.

Valaris 8504 rig; Curtesy of Valaris — Valaris 8504 rig, formerly ENSCO8504; Courtesy of Valaris

JAPEX completed the exploratory drilling in the offshore Hidaka area of Hokkaido on June 10, 2026. The firm had been conducting the activity to confirm the presence of natural gas since March 24, 2026. The rig that undertook the drilling work has been identified as Valaris 8504.

The operation was conducted based on the results of the exploratory drilling operations carried out in the area in 2019, approximately 5 kilometers northwest of the location already drilled around 50 kilometers offshore in the same area, at a water depth of 1,070 meters.

The Japanese player conducted exploratory drilling to a water depth of 1,900 meters, with understanding and cooperation from the local community, including the fishing industry and local government.

“We tested the reservoir where indications of natural gas were recognized during the drilling and confirmed the presence of natural gas in part of the reservoir and acquired geological data,” emphasized JAPEX.

The exploratory drilling was selected by the Agency for Natural Resources and Energy of the Ministry of Economy, Trade and Industry as a subsidized project under the ‘Subsidy for Geological Survey for Domestic Oil and Natural Gas in FY2024.’

According to the Japanese firm, the confirmed natural gas volume does not meet the criteria for “immediate commercialization.” However, JAPEX will analyze and evaluate the obtained data to consider the possibility of an exploration and development opportunity in the area.

View on Offshore-energy.