Carbon sequestration for geological negative emissions of the shale gas value chain in China

Carbon sequestration in shale gas operations represents a crucial pathway to achieve Geological Negative Emissions, which is essential for global 1.5 °C targets. However, the emissions reduction potential and economic viability of this approach in China's shale gas value chain remain unclear. This study quantifies the potential for transforming China's shale gas value chain from an emission source to a carbon sink, while revealing spatial heterogeneity in economic feasibility. Results demonstrate that synergistic deployment of CO₂-based technologies can achieve Geological Negative Emissions across the value chain, with national carbon sink potential reaching 66 billion tonnes of CO₂-equivalents and shale gas production increasing by 4,518 billion cubic meters. Multi-scenario economic assessments reveal that marine shale in the Sichuan Basin exhibits inherent profitability, whereas continental reservoirs require carbon credit integration or optimized production. Current Chinese carbon market prices provide insufficient incentives, implementing region-specific subsidies and enhancing carbon pricing frameworks could unlock this potential, thereby contributing to national carbon neutrality goals and multiple Sustainable Development Goals.