新疆伽师M_(S)6.4地震前后柯坪断裂土壤气地球化学特征变化

FAULT GAS GEOCHEMICAL CHARACTERISRICS CHANGING OF KEPING FAULT BEFORE AND AFTER JIASHI M_(S)6.4 EARTHQUAKE IN XINJIANG

由于土壤中气体的浓度可能会因为地下应力的变化而改变,通过对2016~2020年10期柯坪断裂土壤气地球化学流动观测结果总结和分析,土壤气浓度的变化不仅和覆盖层的厚度、粒度组合有关,也和断层出露点的破碎程度及断裂的活动状态有关。在伽师M_(S)6.4地震前柯坪断裂逸出气体强度出现了较为显著的增强,表明柯坪断裂西克尔至阿依库勒段活动性增强,地震发生后异常强度增强的区域显著减少与柯坪断裂的断层活动性减弱有关。

As the concentration of gas in soil may change due to change of underground stress,it is said that change of soil gas concentration is not only related to the thickness and particle size combination of overburden layer,but also related to the degree of fracture of fault dew point and the active state of fault through the summary and analysis of the observation results of soil gas geochemical flow in Keping fault form 2016 to 2020.Before Jiashi M_(S)6.4 earthquake,the intensity of gas escaping from the Keping fault increased significantly,indicating that the activity of Xikele Ayikule section of Keping fault increased,and the area with increased abnormal intensity after the earthquake decreased significantly,which is related to Keping fault activity weakening.