2018年5月28日吉林松原发生5.7级地震，为了探究地震对断层气的影响以及震后断层气变化特征，震后在震中区进行了多期土壤氢气浓度观测工作，得到了震中区氢气浓度的最大值、背景值等多项指标。结合地震前后氢气浓度数据，分析震中区震前、震后氢气浓度趋势性变化情况，结果显示：在此次地震活动中，氢气浓度变化有"震前缓慢升高-临震下降-震后迅速升高-强余震前再次骤升"的现象；氢气浓度变化与地震活动间有很好的映震关系，主震对氢气浓度的上升起主要作用，而余震则起诱发作用，余震的活动会使赋存在地下岩石裂隙的氢气释放量增大，表明氢气对余震活动的响应较灵敏；另外，震后某一时刻空气中的氢气浓度也会升高，这可能与区域断层中的氢气逸散到大气中有一定关系。

The Songyuan M_S5.7 earthquake occurred on May 28,2018. In order to study the influence of earthquakes on fault gas and the variation characteristics of fault gas after earthquakes,several periods of soil hydrogen observation were carried out in the epicenter after earthquakes. Finally,the maximum and background values of hydrogen concentration in the epicenter region were obtained. Based on the data of hydrogen variation before and after earthquakes,the trend change of hydrogen concentration in epicenter is analyzed. The results show that during this earthquake activity,hydrogen concentration has the phenomenon of "slow increase before earthquakes-decrease when earthquakes are about to occur-sharp increase after earthquakes-a sharp rise again before strong aftershocks". The variation of hydrogen concentration has a good correspondence with seismic activity. Main shocks play a major role in the increase of hydrogen concentration,while aftershocks play an inductive role. Aftershocks release gases trapped in underground rock fissures faster,so aftershocks make hydrogen concentration change more sensitive. In addition,at a certain time after the earthquake,the concentration of hydrogen in the air will also increase,which may be related to the escape of hydrogen from faults to the atmosphere. In addition,at a certain time after the earthquake,the concentration of hydrogen in the air will also increase,which may be related to the escape of hydrogen from faults to the atmosphere. This study shows that hydrogen changes obviously before and after the earthquake,which has very good indicative significance.

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黑龙江省地震局重点科研项目（201701）、黑龙江省地震局震情跟踪项目（201803）共同资助