The Anomaly Characteristics before Wenchuan Earthquake and Yushu Earthquark in Qinghai Yushu and Delingha Geothermal Observation Wells

详细信息   

• 责任者：He Anhua (Institute of Crustal Dynamics ; China Earthquake Administration ; Beijing 100085 ; China) ; Zhao Gang
• 刊名：Chinese Journal of Geophysics
• 出版年：2012
• 卷期：55(4)
• 关键词：地震前兆 ; precursor ; 地热井 ; geothermal wells ; 青海 ; Qinghai Province
• 页码：p.1261-1268
• 图表：3 illus., 1 table, 27 refs.
• 分类号：0500
• issnNo：ISSN0001-5733
• isbnNo：CN11-2074/P

摘要

In this paper,the data of water temperature observed in Yushu and Delingha（Qinghai Province） geothermal observation wells since 2007 were analyzed systematically,by which precursory anomalies were found in both wells right before the Wenchuan Earthquake（Sichuan Province） and Yushu Earthquake（Qinghai Province） occurred on 12th May 2008 and 14th April 2010 respectively,and similar abnormal phenomena were also detected before other violent earthquakes happened.Furthermore,the information of the precursory anomalies such as anomaly amplitude and duration were analyzed quantitatively,the anomaly curves of each well for different earthquakes were compared in terms of shape,and the correlation of abnormal data was studied.It can be concluded that the shapes of precursory anomaly curves of the two wells for different earthquakes have many similarities.The exploration of the precursory anomalies and their curves will break new ground for earthquake prediction by means of water temperature.Besides,the author discovered that the water temperature anomaly amplitude of Yushu Well varied with earthquake magnitude and epicentral distance,which can be described in detail as follows： the greater the magnitude,the shorter the epicentral distance,while the greater the anomaly amplitude and the longer the anomaly duration.Also the Yushu Well is dominated by medium and long-term anomalies,which will have significant impact on predicting magnitude of earthquakes using water temperature anomalies.On the other hand,the anomalies of Delingha Well were short term and imminent,and this feature will be very useful when estimating the occurrence time of an earthquake by analyzing data of water temperature.