Sichuan Basin, brimming with natural gas, is hailed as the "Kingdom of Natural Gas," ranking first in China for both reserves and production. However, you might not know that in the oil and gas sector, Sichuan has long been an "unbalanced student"—excellent in gas but consistently failing in oil. The label "gas-rich, oil-poor" has been worn for decades.
In 2023, Sichuan's crude oil production hit a low of less than 20,000 tons annually, a stark contrast to Daqing Oilfield's 30 million tons the same year—only 1/1500th. But after hitting bottom, a rebound has begun. In recent years, crude oil exploration and development in the Sichuan Basin have seen frequent breakthroughs, with multiple records continuously being refreshed. A new round of oil campaign has already commenced.
On May 8, in Ma'an Town, Yilong County, Nanchong City, the Longye 102H well—the first shale-type shale oil pilot test well by PetroChina Southwest Oil & Gasfield Company—officially commenced drilling. The well is designed to reach a depth of over 5,000 meters, targeting the Jurassic Lianggaoshan Formation, which dates back hundreds of millions of years. A few days later, on May 12, a record-breaking figure emerged: a daily drilling footage of 1,015 meters. To put this in perspective, the previous highest record in this block was 600 meters per day. "Everyone was thrilled when we saw the footage break 1,000 meters," said Rao Fujia, the well manager of Longye 102H, still exhilarated when visited on May 13.
What is a pilot test well? Rao Fujia explained it is used to verify technical feasibility and optimize development plans before large-scale commercial development. "We are drilling for shale oil in the Lianggaoshan Formation. Geological predictions suggest Lianggaoshan has great potential. Now we need to verify if there is oil down there." Shale oil, an unconventional petroleum resource trapped in shale formations, is seen as a crucial replacement force for China's long-term stable crude oil production. PetroChina's deployment of seven shale oil pilot test wells in the Yilong area of Nanchong underscores the block's potential for increasing reserves and production. "Only a few wells in Southwest Oil & Gasfield have a designated well manager, which shows the importance of this well," Rao Fujia noted.
The drilling operation is handled by Chuanqing Drilling Team 70229. Team leader Li Changjin, with over a decade of experience drilling gas wells, is working on an oil well for the first time. "Drilling a conventional gas well used to take about a year. Now, for an oil well, we aim to complete drilling in just over 30 days. The pace is incredibly fast," Li said. What drives the daily kilometer progress? Rao Fujia attributes it to Southwest Oil & Gasfield's high-level promotion. To enhance the efficiency of pilot test wells in the Longgang area, the company established an integrated on-site working group and a well manager system, with management personnel stationed throughout to oversee operations, implement specialized drilling acceleration measures, and optimize workflows. "Everyone is determined to strike oil," Li Changjin shared with anticipation. When he first started drilling, veteran team leaders told him about striking oil in Suining Anju in the 1980s, where it could be directly used for motorcycles. "But in my over ten years on the job, I've never seen what oil looks like."
Shale oil carries high expectations. A clear signal came at the end of 2025 when Southwest Oil & Gasfield officially established a Crude Oil Division, with Tang Qingsong appointed as manager. Tang, previously responsible for natural gas production in the Development Management Department, was tasked in 2023 with a dual role focusing on oil. Initially puzzled—"At that time, the entire company was striving to produce 50 billion cubic meters of natural gas. Why focus on oil now?"—he later realized, after leading his team to delve into data, conduct field surveys, and hold discussions, that crude oil indeed holds significant potential.
Sichuan is the birthplace of New China's oil campaigns. Over the past 60 years, Southwest Oil & Gasfield has discovered multiple crude oil reservoirs and put over a thousand wells into production. However, limited by geological understanding and engineering technology, fewer than a hundred wells are actively producing crude oil. Why establish a Crude Oil Division? Tang Qingsong believes it reflects both original intent—Southwest Oil & Gasfield was born for oil and thrived on gas, with "finding oil fields" being the long-held aspiration of generations of oil workers—and determination: establishing a dedicated division to extract underground oil when the nation needs it most.
Currently, Southwest Oil & Gasfield has set a development goal of "increasing reserves by 100 million tons and boosting production by 1 million tons." While solidifying its position as the nation's second-largest gas field and striving to become the largest, the crude oil sector is also making vigorous efforts. "Balancing oil and gas" and "prospering in both oil and gas" hold promising prospects.
In recent years, the Sichuan Basin has witnessed a new narrative for crude oil:
Bazhong Pingchang Oilfield: In September 2024, reserves of the Ping'an 1 block were reviewed and filed by the Ministry of Natural Resources. By 2025, Bazhong's prospective oil resources reached about 2.5 billion tons, with annual production at 22,000 tons, a year-on-year increase of over 360%.
Chongqing Fuxing Oilfield: In July 2025, the first phase of proven oil reserves exceeding 20 million tons passed review, making it the first shale formation oilfield in the Sichuan Basin.
Nanchong Shunqing Oilfield: In December 2025, newly added proven crude oil reserves exceeding 20 million tons passed review, marking the birth of the first tight oilfield in the Sichuan Basin. On May 10, the latest news reported that the first development pilot test program well for Jurassic crude oil in central Sichuan, located in Shunqing Oilfield, completed drilling. Through the phased implementation and technological iteration of nine pilot test wells, preliminary technical policies for zonal and classified development of Jurassic crude oil in central Sichuan were clarified, providing a technical basis for high-quality replication and promotion.
Currently, PetroChina's Southwest Oil & Gasfield and Daqing Oilfield, along with multiple teams from Sinopec, have once again gathered in the Sichuan Basin to launch a new round of oil campaign. PetroChina has integrated professional forces in oil and gas exploration and development, geophysical exploration, logging, and research to establish a crude oil production increase consortium, conducting in-depth original research.
Why has crude oil exploration and development achieved breakthrough progress? To answer this, one must first ask: Why was oil not found in the past? "The approach was wrong," said Yang Yi, Deputy Director of the Geology and Engineering Department of Southwest Oil & Gasfield's Crude Oil Division, bluntly. He explained that past oil exploration focused on "finding oil outside the source"—searching for places where oil and gas migrated and accumulated, akin to looking for "children." "But the geological structure of the Sichuan Basin is too complex, making it hard to find the 'children.'" Now, the approach has changed. "We've started 'finding oil within the source'—directly targeting the hydrocarbon source rocks that generate oil, or finding the 'mother.'" He used an analogy: "In the past, hydrocarbon source rocks were thought to be like a chicken that laid eggs and was done. Later, we realized this chicken still has many eggs inside." This shift in understanding has directly opened new prospects for increasing reserves and production of crude oil in the Sichuan Basin.
The favorable area for crude oil in the Sichuan Basin spans about 50,000 square kilometers, concentrated in the triangular zone of central Sichuan, northeastern Sichuan, and eastern Sichuan. Vertically, there is a "five-story" structure—the entire Jurassic sedimentary system, including the Shaximiao Formation, Lianggaoshan Formation, Da'anzhai Formation, Dongyuemiao Formation, and Xujiahe Formation, all contain oil. The focus of crude oil development has shifted from conventional oil to unconventional directions like shale oil and tight oil, building on breakthroughs in shale gas and tight gas exploration and development.
Shale oil and shale gas share highly similar technical routes: horizontal wells + volume fracturing + long horizontal sections. However, shale oil has a natural advantage—shallower burial depth. Shale gas reservoirs are typically buried at depths of 3,500–4,500 meters, while shale oil is only 2,000–3,000 meters deep, enabling faster development and production cycles.
Challenges remain real. "Our current technology is called shale oil 2.0, which can support development but isn't highly profitable," Tang Qingsong admitted. "It's right at the breakeven point—neither making nor losing money." What to do? Two paths: reduce costs and increase EUR (Estimated Ultimate Recovery). How to achieve this? Set strict constraints from the start. "We won't repeat the old path of high initial costs like shale gas. From the beginning, we limit: if a well can only produce 20,000 tons of oil, I can only invest 20 million; if it can produce 50,000 tons, I can invest 50 million. All parties, whether client or contractor, operate around this mechanism." From its inception, the Crude Oil Division made "cost reduction" its first survival principle.
The goal is clear: by 2030, Southwest Oil & Gasfield's annual crude oil production will reach 500,000 tons. This means production will increase more than tenfold in five years. Meanwhile, the Sichuan Basin's crude oil production is expected to reach 1 million tons by the end of the "15th Five-Year Plan" period.
At the Longye 102H well site, the信念 of Rao Fujia, Li Changjin, and all on-site personnel is even firmer than the roaring drilling rig. "We will succeed!" their words resonate powerfully. Can Sichuan, long labeled "gas-rich, oil-poor," defy fate? The answer awaits.
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