On May 13, Sinopec achieved another major breakthrough in its “Deep Earth Project – Sichuan-Chongqing Natural Gas Base.” The Tiefa-1 Side HF Well, deployed by Zhongyuan Oilfield in the Puguang area of the Sichuan Basin, recorded a high industrial gas flow with a daily output of 314,500 cubic meters. The well, with a vertical depth exceeding 5,300 meters and a horizontal section stretching 1,312 meters, set a new national record for shale gas well depth in China.

This breakthrough is expected to greatly advance large-scale production capacity and reserve expansion in the Puguang area. It also provides a valuable reference for deep shale gas exploration in the Sichuan Basin and supports the region’s broader shale gas development.

Threading a Needle at Great Depths

The Puguang gas field is China’s first large-scale deep, high-sulfur gas field to be developed, having operated efficiently for over 20 years. In pursuit of long-term stable output, Sinopec has turned its attention to the deeper Permian formations beneath Puguang.

These ultra-deep Permian shale gas resources lie mostly below 4,500 meters and are located in geologically and topographically complex areas. Rapid variations in subsurface velocity make them difficult to track, earning the area the nickname “deep earth forbidden zone” in the industry.

To overcome this major challenge, Sinopec developed new processing techniques, achieving a 100% high-quality shale encounter rate in horizontal drilling. The precision has been compared to “threading a needle thousands of meters underground,” leading to the successful drilling of the Tiefa-1 Side HF Well.

Creating Artificial Gas Pathways in High-Pressure Formations

To address challenges such as high formation pressure, large stress differentials, and multiple limestone interlayers, the project team used Sinopec’s self-developed 175 MPa ultra-high-pressure fracturing equipment. With advanced modifications like ultra-high-pressure and high-flow-rate cross-layer fracturing, the team dynamically optimized parameters for each section, effectively creating an intricate network of artificial gas pathways at a depth of 5,300 meters.

This successful volume fracturing in an ultra-deep horizontal well enables recovery from even the deepest and most remote parts of the reservoir, maximizing the efficiency and economic value of gas extraction.

Zhongyuan Oilfield’s Chief Expert Peng Jun stated that preparations are underway for a comprehensive exploration and development plan targeting Permian shale gas in the Puguang region. With continued advancements in geological evaluation, geophysical technologies, and fracturing techniques, exploration and production efficiency will be further enhanced, transforming the "deep earth forbidden zone" into a "deep earth granary."

Advancing China’s Shale Gas Industry

Sinopec continues to spearhead the high-quality development of China’s shale gas industry. With a resource structure characterized by abundant coal, limited oil, and scarce gas, China has long been a major oil and gas importer. Shale gas exploration and development hold strategic importance for the country’s energy landscape.

In 2012, Sinopec discovered the Fuling shale gas field, marking the start of China’s commercial shale gas development and making China the third country—after the U.S. and Canada—to achieve this milestone.
In 2017, the Fuling field became China’s first shale gas field with 10 billion cubic meters of annual production capacity.
In 2020, Phase I of the Weirong shale gas field became the nation’s first deep shale gas field with proven reserves exceeding 100 billion cubic meters.
In 2024, exploratory wells like Jinye-3 and Ziyang-2 continued to open new potential for reserve growth and production, providing sustained momentum for clean energy development.