THE CHARACTERISTICS OF SUBSURFACE FLUID ANOMALIES IN LANGFANG REGION BEFORE ZHANGBEI M6.2 EARTHQUAKE

The observation in Antoutun well and Qianniu No.6 well located in Langfang region is static water level, The observation in Wenan well that has been carried out many years by Wenan Seismostation is water radon.The observation of the 3 wells started from 80s of last century, and their data is continuous and reliable.Through study we found that there were obvious anomalies before Zhangbei M6.2 earthquake occurred on Jan.10 of 1998 and its strong aftershocks.The synthetic characteristic of anomalies for the event is also discussed here.