汶川MS8.0地震前后龙门山断裂带CO和CH4排气增强*
崔月菊1,杜建国1,陈 杨2,刘 雷1,刘 红1,易 丽1,孙凤霞1

(1. 中国地震局地震预测重点实验室(中国地震局地震预测研究所),北京 100036; 2. 中国国土资源航空物探遥感中心,北京 100083)

汶川地震; 龙门山断裂带; 高光谱; 气体地球化学

Increasing of CO and CH4 Gas Emission at Longmenshan Fault Zone before and after Wenchuan MS8.0 Earthquake
CUI Yueju1, DU Jianguo1, CHEN Yang2, LIU Lei1, LIU Hong1, YI Li1, SUN Fengxia1

(1. Key Laboratory of Earthquake Prediction, Institute of Earthquake Science, CEA, Beijing 100036, China)(2. China Aero Geophysical Survey & Remote Sensing Center for Land and Resources, Beijing 100083, China)

Wenchuan Earthquake; the Longmenshan Fault Zone; hyper-spectrum; gas geochemistry

备注

利用卫星高光谱数据研究了汶川地震前后震中周围及沿断裂带相同面积区域的CO和CH4总量的变化和相关程度。结果 表明:(1)龙门山断裂带地区常年有地下气体沿断裂带向大气中释放,CO沿断裂带释放,受构造控制明显,而CH4除了受构造控制影响外,还受川西地区地下天然气的弥漫式扩散影响;(2)汶川地震的发生促进了地下气体的释放,汶川地震前约1.5个月至震后3个月左右有大量的地下CO和CH4气体沿龙门山断裂带释放到大气中,并且距离震中越近,排气量越大。研究结果对地震监测、地气交换和环境地球化学监测有重要意义。

Based on the satellite hyper-spectral data, we studied the variation and correlation of total column CO and CH4 in the same areas around the epicenter and along the fault zone before and after the Wenchuan earthquake. The results indicated that:(1)The lager amount of gases emittied from the underground into the Wenchuan atmosphere along the Longmenshan Fault Zone throughout the year. The emission of CO along the fault was controlled obviously by the tectonic, while the emission of CH4 was not only controlled by the tectonic, but also influenced by the diffuse emission of natural gas in the Western Sichuan area.(2)The emitted underground gas was induced by the Wenchuan MS8.0 earthquake. A large number of CO and CH4 emitted from underground into the atmosphere along Longmenshan Fault Zone from about 1.5 months before the earthquake to 3 months after the earthquake, and the closer to the epicenter,the larger the amount of emitted gases was. The obtained results are significant to the earthquake monitoring, gas exchange between atmosphere and solid earth and environmental geochemistry monitoring.