To investigate the characteristics and formation mechanisms of unexplained gas outbursts in high-altitude tunnels,this paper employed a multidisciplinary approach encompassing data collection,field surveys,testing,mon itoring,experimental petrology,and geochemical experimentation.By examining the geological environment hosting the outburst gases,the study elucidated the composition,evolutionary processes,and governing patterns of these gases.Integrating regional geological evolution,a model for the formation and evolution of the outburst gases was established.The findings reveal:(1)The Mainling Adit and its surrounding area lack the lithological conditions necessary for the development of substantial hydrocarbon resources;hence,the outburst gas is categorized as a mixed organic-inorganic gas.(2)The concentration of the outburst gas exhibits a decreasing trend over time,indicating limited reserves and non-flammability,with moderate to low corrosivity.(3)The Mainling Adit gas outburst represents a diverse and complex mixture of organically and inorganically derived gases,whose formation involves sequential organic and inorganic stages.The region's historically active magmatic activity and the presence of carbonate rocks at gas emission sites provide evidence for the inorganic origin of the outburst gases.These results serve as a reference for analogous studies and evaluations of gas outbursts in high-altitude tunnels.
NETL
NSTL
维普
万方数据
