Daji gas field, China's largest coal-rock gas project, has surpassed an annual production capacity of 4 billion cubic meters, solidifying its position as a critical replacement resource for China's domestic natural gas growth.

The field now accounts for more than 75 percent of the country's total coal-rock gas output, said its operator China National Petroleum Corp.

Coal-rock gas is an unconventional form of natural gas found either adsorbed or free within deep coal seams, typically at depths exceeding 1,500 meters.

While the resource offers vast exploration prospects, its extraction has historically been hindered by high technical barriers and complex geological conditions.

Between 2023 and 2025, the Daji field achieved a multi-stage surge in production, leading the development of China's unconventional gas industry. The breakthrough underscores China's efforts to enhance energy security by tapping into deep, unconventional reserves to offset its reliance on energy imports.