Bayanhot Oilfield's CCUS construction site. [Photo/Bayanhot Daily]

The Hetao Basin in Inner Mongolia on Dec 21 reached a major milestone as cumulative crude oil production surpassed 5 million metric tons – marking not only a numerical breakthrough but also a significant advance in China's push into deep oil and gas exploration.

In early 2018, China National Petroleum Corporation's North China Oilfield Company secured exploration rights in Inner Mongolia's Bayanhot and the newly identified Hetao Basin.

Guided by a "resources first" strategy, it intensified risk-focused exploration across new areas, plays, layers, and reservoir types, driving a new wave of reserve growth through integrated exploration of shallow, mid, and deep layers.

From the first discovery well to 5 million tons of output, the "Bayanhot speed" has repeatedly set records. The first 1 million tons took 49 months, while the next four milestones were achieved in 13, 10, nine, and eight months, respectively – reflecting accelerated progress in geological understanding, engineering technology, and organizational efficiency, as well as a steady boost to national energy security.

Technological innovation underpins high-quality development. Geologists performed detailed reservoir characterization and built 3D geological models to support efficient development.

The company also pioneered tailored development models and enhanced oil recovery measures, commissioning China's first conglomerate oilfield using early-stage oxygen-reduced air injection – an initial success for a new gravity-driven development approach in newly discovered reservoirs.

While advancing deep subsurface exploration, the company's Bayanhot exploration and development branch has prioritized environmental protection on the surface, pursuing a dual strategy of "underground reserve growth and above-ground greening". 

Breaking from traditional waterflooding concepts, it is exploring carbon capture, utilization and storage (CCUS) to enhance oil recovery in deep sandstone reservoirs. To date, three pilot zones have injected more than 110,000 tons of CO₂, setting domestic records for the deepest liquid CO₂ injection and profiling tests.

Committed to green development and environmental protection, the branch has developed a diversified model integrating oil and gas with solar, wind, and solar thermal energy. The Bayanhot Oilfield now has 16.9 megawatts of photovoltaic capacity, generating about 30 million kilowatt-hours of green electricity annually. Its "PV + desert control + animal husbandry" model has rehabilitated around 450 mu (about 30 hectares) of desertified land, achieving coordinated progress in energy development and ecological restoration.