Characteristics and Mechanism of Water Temperature Anomalies in Eryuan Dian 20 Well
ZI Chengzhu
ZHANG Xiang
ZHANG Yuan
YANG Shufeng
Abstract：Based on the earthquake cases,the water temperature observation data of the Eryuan Dian 20 well were analyzed.The results showed that the water temperature anomaly has a good short-term indicating significance for the occurrence of medium strong earthquakes in the 200 km area around the measurement point.Before the earthquake,the anomalies mostly showed a downward change,lasting for 2-6 months,with a change range of 100‰ to 400‰℃.Earthquakes occurred either during the ongoing thermal anomaly phase or within two months after the anomaly continued.Based on the summarized abnormal characteristics and combined with hydrochemical analysis,temperature gradient analysis,and water level observation analysis,the possible causes of the anomalies were studied.The reason for the abnormal water temperature in the Eryuan Dian 20 well may be due to enhanced regional tectonic activity.Under the action of tension,the decrease in pore pressure causes the well water to flow back into the aquifer,leading to thermal convection inside the wellbore and the decrease of the water temperature at the sensor location.
Keywords：Eryuan Dian Well 20Water temperature observationAnomaly characteristicAnomaly mechanism
Publication Date：2025-03-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 59-67 )