页岩气勘查开发对含水层潜在甲烷污染成因机理

Genetic mechanism of potential methane contamination of aquifer caused by shale gas development

我国页岩气资源潜力丰富,勘查开发刚起步,环境保护工作需要基本理论和技术方法支撑。文章围绕我国页岩气勘查开发规划,以保障国家能源安全为宗旨,针对页岩气勘查开发过程中环境影响热点课题——含水层潜在甲烷污染成因机理问题,对其研究意义和国外研究现状进行了系统的分析和综述。得出目前国外该领域的研究可归纳为:(1)含水层中多种不同成因来源甲烷识别研究;(2)含水层甲烷污染途径与迁移通道识别技术研究。然而以上研究存在缺乏系统性证据或模拟中地质条件概化处理过于理想化等不足,有望在以下几方面投入更多的研究:(1)建立含水层中多种不同成因来源甲烷判定指标体系;(2)不同成因来源甲烷的定量化分析方法;(3)复杂地质结构和地层条件下的多次脉冲式非达西流垂向迁移模拟。

China has abundant resource potential of shale gas.The exploration and development of shale gas has just started,and the multitude of environmental protection work requires basic theory and technique support.The focuses of this paper is on the exploration and development of shale gas plan of China for the purpose of ensuring national energy security.The authors systematically analyze and review the significance,aboard research status and research tendency of the genetic mechanism of potential methane contamination of groundwater,which is one of the hot topics in environmental impact during shale gas exploration and development.The result shows that the research in this area can be summarized two parts：（1） identification of genetic source of various types of methane in aquifers.（2） Identification of contamination pathways and migration channels of methane to aquifer.However,these studies lack systematic evidence or the treatment of geological（hydrogeological） conditions in the model is too idealistic.More attention is expected to pay in the following aspects：（1） establishing the index system of different genetic sources of methane in aquifer;（2）requiring quantitative analysis of different genetic sources of methane;（3） conducting non-Darcy flow vertical migration simulation under conditions of complex geological structure and formation.