[关键词]
[摘要]
2018年9月以来,河北省邢台市出现了地下水位大幅回升、多口干涸泉眼复涌等宏观异常现象。为判定异常现象是否与区域内构造活动和地下应力改变有关,2019年4~6月进行了3期现场调查,并对3口灌溉井和6处地表水进行水样采集,分析了水化学离子浓度和氢氧稳定同位素等水化学数据。结果表明,3口灌溉井具有地表水的特征,补给来源相似且与地下水存在一定的水力联系;受区域煤矿资源丰富及人类活动的影响,水体中富含SO42-离子。结合异常出现前的生态补水资料,分析认为2018年9月以来河北省邢台市水位抬升现象可能是由邢台地区生态补水引起的,与区域内构造活动和地下应力改变没有直接联系,排除其是地震宏观前兆的可能。
[Key word]
[Abstract]
The macro anomalies,such as rise of groundwater level,re-gushing of several dry-up springs have occurred in Xingtai city,Hebei Province since September 2018. The field investigations were conducted in three times in order to determine whether such anomalies are related to regional tectonic activity or change of underground stress. We collected 3 samples from irrigation well water and 6 samples from surface water. Hydrochemical ion concentration and isotopic ratios of the samples were analyzed. The results are as follows:① samples from 3 irrigation wells show the similar supply source and a certain hydraulic connection with ground water;② the enrichment of SO42- in water is caused by the richness of coal resources and human activity. We conclude that the anomaly phenomena probably were caused by ecological water supplement project based on ecological water supplement data before occurrence of anomalies,and no evidence was found to support the correlation between the cause of anomalies and regional tectonic activity or change of underground stress. Consequently,the possibility of seismic macro precursor anomaly is eliminated.
[中图分类号]
P315
[基金项目]
中国地震科学实验场的地震可预测性国际合作研究(2018YFE0109700)、中国地震局震情跟踪定向工作任务(2019010310)和中国地震台网中心青年科技基金(QNJJ201809)共同资助