2003年呼和浩特城区流体异常特征及其地震地质意义

Seismological significance and features of fluid anomalies occurred in Hohhot City in 2003

通过对2003年3月呼和浩特城区出现流体异常的落实和跟踪监测,讨论了水温和水汞异常的成因,并分析了大青山地震带的地震动态。地下流体和地震地质资料表明,呼和浩特城区3月中旬出现的地下流体异常是区域地壳活动的结果,是呼 包盆地地壳活动引起新华广场断裂的活动,断裂活动破坏了地下浅层的隔水层,深层热水上涌形成了流体异常。呼和浩特城区流体异常与6月10日托克托县MS4.2地震都是岩石圈深部活动在地壳内的反映,2003年3月以来呼和浩特城区出现的流体异常应该是地震的前兆。西龙王庙的流体异常还未完全结束。

Genetic mechanism of fluid anomalies is discussed and seismic tendency along Daqingshan earthquake zone is analyzed based on observation and monitoring of temperature and chemical components of well waters. The data indicate that fluid anomalies occurred since March 2003 in Hohhot City were resulted from activity of Xinhua Yuangchang fault that caused the deeper hot groundwater migration upwards. The anomalies of temperature and mercury etc. in the wells were the precursors of Toketo earthquake with M_S4.2 occurred on June 10. The earthquake and the fluid anomalies were resulted from new activity of regional tectonics. In addition, the fluid anomalies are continued so far and regional seismic activity is becoming much stronger. Therefore, it can be predicted that earthquake M=5 in Richard scale will probably occur in one year and there is the possibility of M 6 to occur in coming 2 to 3 years along the middle and eastern segments of Daqingshan earthquake zone.