东海陆架盆地新生界咸水层二氧化碳封存地质条件及封存前景

Geological conditions and prospects of carbon dioxide storage in the Cenozoic saline water layers of the East China Sea Shelf Basin

目前可用于封存二氧化碳的地质体包含深部咸水层、枯竭油气田、玄武岩等,其中,深部咸水层广泛分布于全球大多数沉积盆地,具有封存能力大、技术成熟、安全性高、成本低等优点,是一种重要的二氧化碳封存地质体。相较于陆域,海域碳封存具有封存潜力大、安全性高、环境影响小、封存周期长等优点,是实现“双碳”目标的重要途径。东海陆架盆地面积大,盆地构造稳定性较高,属于次冷-次热盆地,碳封存目标层厚度大、分布广,具有良好的咸水层二氧化碳封存地质条件,且盆地油气勘探开发程度较高,实施二氧化碳咸水层地质封存的工程条件成熟。在中国海域含油气盆地中,东海陆架盆地咸水层二氧化碳地质封存适宜性为高适宜。综合考虑勘探开发程度、区域构造稳定性、地热条件、二氧化碳咸水层地质封存物质条件和地质封存工程实施条件等可影响二氧化碳地质封存前景评价的参数,分别评价了各区带二氧化碳封存前景。其中,台北坳陷和浙东坳陷碳封存前景最好,适宜实施二氧化碳地质封存;长江坳陷和海礁隆起碳封存前景较好,可作为实施二氧化碳地质封存的备选区带。

At present,geological bodies that can be used to store carbon dioxide include deep saline water layer,depleted oil and gas fields,basalts,etc.The deep saline water layer is widely distributed in most sedimentary basins in the world,has the advantages of large storage capacity,mature technology,high security,and low cost,and is an important carbon dioxide storage geological body.Compared with land areas,a carbon storage in sea areas has the advantages of large storage potential,high safety,small environmental impact,and long storage period,and is an important way to achieve the goal of"carbon peaking and carbon neutrality".The East China Sea Shelf Basin has a large area and high structural stability.It is a sub-cold–sub-hot basin.The carbon storage target layer is thick and widely distributed,and has good geological conditions for carbon dioxide storage in saline water layer.Furthermore,the engineering conditions for geological storage of carbon dioxide in saline water layers are mature.Among the oil and gas basins in China’s maritime area,the suitability for geological storage of carbon dioxide in saline water layers in the East China Sea Shelf Basin is great.After comprehensively considering the parameters that affect the evaluation of carbon dioxide geological storage prospects,such as the degree of exploration and development,regional structural stability,geothermal conditions,geological storage material conditions in saline carbon dioxide layers,and geological storage engineering implementation conditions,the prospects for carbon dioxide storage in each zones were evaluated.Results show that the prospects for carbon dioxide storage are the best in Taipei Depression and Zhedong Depression,and they are suitable for geological storage of carbon dioxide,followed by the Changjiang Depression and Haijiao Uplift that and can be used as candidates for carbon dioxide geological storage.