泥火山在新疆北天山地区有广泛的分布,泥火山活动时可将大量深层有价值的信息带到地表,通过跟踪分析其活动特征和喷涌物化学组分变化,为区域中强地震预测提供可靠依据。本文首先介绍新疆北天山地区泥火山分布及活动特征,简述泥火山监测的发展历程: 连续监测方式由1990年的喷涌“脉冲”记录,到2011年的视频实时监控,再到2023年实现了特定气体流量的连续在线监测。总结周边300km范围内天山中段发生的9次5级和4次6级地震震例发现,泥火山异常活动特征为“背景值—上升—转折—下降—背景值”的时间进程变化,异常开始距发震时间为6～12个月,地震多发生在转折后,可将其作为天山中段中强震震情跟踪的中期指标; 泥火山喷涌物中的地球化学组分为高值异常,离子(F^-、CO₃^2-等)可作为中强震震情跟踪的短期指标,逸出气体(CH₄、Rn等)可作为中期指标。最后,利用新源—和静6.6级、呼图壁6.2级和精河6.6级3个地震回顾了乌苏艾其沟等泥火山在震情跟踪中的实际应用情况。

Mud volcanoes are widely distributed throughout the northern Tianshan region of Xinjiang,and their activities bring valuable information from deep layers of the Earth to the surface. By tracking and analyzing the activity characteristics and changes in the geochemical components of these mud volcanoes,researchers can gain reliable data for predicting moderate-to-strong earthquakes in the region. This article briefly introduces the distribution and activity characteristics of mud volcanoes in Xinjiang and details the development of monitoring techniques. Monitoring methods have evolved significantly over time,from regular sampling analysis to continuous gas flow monitoring in 2023. By summarizing data from nine earthquakes with magnitudes of 5.0 and four earthquakes with magnitudes of 6.0 within a 300km radius of the middle Tianshan Mountains,the anomalous activity of mud volcanoes follows a time course pattern of “Background Value-Increase-Turning Point-Decrease-Return to Background.” These anomalies typically begin about 6～12 months before an earthquake occurs,with the earthquake most often happening after the turning point,making this a useful mid-term indicator for tracking seismic activity in the region. Geochemical components from mud volcano eruptions show clear signs of abnormality. Elevated ion concentrations(F^-,CO₃^2-) serves as short-term indicators for tracking moderate-to-strong seismic activity,while escaping gases like methane(CH₄) and radon(Rn) can act as mid-term indicators. The paper also presents case studies of mud volcano activity,geochemical changes,anomaly verification,and earthquake prediction before several notable earthquakes:Xinyuan-Hejing M6.6 earthquake,Hutubi M6.2 earthquake,and Jinghe M6.6 earthquake.

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浙江省地震局科技项目(2023zjj01)、中国地震局地震科技星火计划项目(XH20066)共同资助