Sinopec made a major breakthrough in deep shale gas exploration
On June 30, Sinopec’s Xinye 1 well deployed in Qijiang, Chongqing, obtained a daily output of 530,000 cubic meters of shale gas, marking that the Xinchang structure has realized a resource of 100 billion cubic meters. So far, the complex structural belt “Xinchangnan-Dongxi-Dingshan-Lintanchang” in the basin margin of southeastern Sichuan Basin has formed an overall contiguous piece, and the overall resource volume has reached 1,193.05 billion cubic meters. The second trillion cubic shale gas resource position in China will make an important contribution to ensuring my country’s energy security.
Xinye 1 Well, completed at a depth of 5756 meters, is a deep shale gas risk exploration well deployed by Sinopec Exploration Company in Xinchang Structure in Qijiang District, Chongqing. Geologically, the Xinchang structure belongs to the complex structural belt in the basin margin of southeastern Sichuan. Previous studies have shown that this structural belt has a large favorable area and large resources for ultra-deep shale gas, and is an important area for Sinopec shale gas reserves and production.
“Xinchang South-Dongxi-Dingshan-Lintanchang” has an average depth of more than 3,500 meters, and the deepest drilled Well Dingye 8 gas layer reaches 4,614 meters. Generally speaking, shale gas buried deeper than 3500 meters is defined as deep shale gas. Deep shale gas passes through many strata, and there are many world-class problems such as large shale burial depth and complex in-situ stress, which require high technical requirements and are difficult to explore and develop. If the development of shallow shale gas is to expand the “small intestine trail” into a “highway”, then the development of deep shale gas is to build bridges on the Qinghai-Tibet Plateau and build complex interlaced “winding mountain roads”. Imagine. After a major exploration breakthrough was made in the Fuling shale gas field in 2012, Sinopec turned its attention to the complex structural belt in the basin margin in southeastern Sichuan, established a deep shale gas technical research team, and continued to carry out technical research on deep shale gas target evaluation and other technical research. The deep shale gas volume fracturing technology has been developed, and the drilling rate of high-quality shale is 100%. The fracturing equipment, tools and materials have all been localized, which greatly reduces the construction cost. In 2019, a strategic breakthrough was made in deep shale gas exploration. After that, the exploration of deep shale gas was further promoted, and the position of trillion cubic meters of shale gas resources was confirmed.
Sinopec attaches great importance to the exploration of deep shale gas, and innovates to form deep shale gas exploration theory and technology. In 2017, Sinopec established a deep shale gas research leading group and a deep shale gas research pilot area in the Dongxi structure, focusing on theoretical and technical research. After years of comprehensive research and exploration practice, the theoretical understanding of deep shale gas geology has been formed, the development and maintenance mechanism of deep shale pores in deep water shelf facies has been successfully revealed, and it is clear that deep shale can develop “high-porosity” high-quality reservoirs and clear “deep shale”. The formation of deep shale gas sweet spot prediction technology, it is proposed that “high-quality shale development, high fluid pressure, development of micro-fractures, and low in-situ stress” are the key elements for deep sweet spot evaluation, and the innovative formation is based on high-precision seismic exploration. It has developed a deep shale gas fracturing engineering technology, effectively solving the problems of deep shale buried depth, strong plasticity, high in-situ stress, and difficulty in fracturing stimulation, forming deep shale “dense cutting, increasing The three-dimensional fracture network fracturing technology of companding body, balanced extension, and keeping filling”.
Next, Sinopec will strengthen the fine evaluation of Xinchang structural targets, strengthen the overall evaluation and deployment of “Xinchang South – Dongxi – Dingshan – Liangcun North” in southeastern Sichuan, and strive to achieve new exploration breakthroughs.
