Research Of The Observational Method For Geotemperature About Seismic Response

Earthquake monitoring is the main means of collecting all aspects of earthquake information,and geotemperature is one of the important observation content.Because the capital area has a large population density and a high degree of economic development,the area has always been a key area for earthquake monitoring.The main area of the research in this article is near the Houhaoyao seismic station in the northwest of the capital circle in Huailai.The shallow layer temperature in this area is taken as the research object.According to the geothermal observation data from 2012 to 2015 in different layers of the experimentation area in Huailai,the data are analyzed with MAPSIS,MAPINFO,SPSS and other software,and some conclusions can be drawn.The geothermal data of multiple depths in well No.4 of Huailai were obtained,and the data were preprocessed and analyzed by correlation analysis to be drawn.It can be concluded that the temperature of the stratum below the depth of 3.2 meters in the well is basically not affected by short-term weather,but only with slow annual variation.According to the field survey results,it is concluded that the depth of the shallow stratum suitable for the equipment is under 3.2 meters,and the geotemperature data between 3.2 and 5 meters in the previous years can be used for earthquake-precursor research.Using the discrete wavelet transform to analyze the temperature data of the temperature and the depth of 4 meters,the detail coefficient of each period is obtained.It can be seen that the high frequency component of the geotemperature data of the 4 m depth is almost inexistent,and the temperature data has a distinct high frequency component.After the continuous wavelet analysis based on FFT,it can be seen that with the change of time,the absolute value of the wavelet coefficients of the 4 m depth geotemperature in the large scale(scale and frequency inverse ratio)is larger,and the wavelet coefficients in the small scale are very small,which conforms to the general situation.It is verifiable that the geotemperature of 4 m depth has been basically rid of the short-time influence of the air temperature,and the geotemperature detector can be set up at this depth to monitor the change of shallow ground temperature.The data of temperature sensors in four directions of East,West,South and North of Huailai experimental well No.3 are plotting,and the scale of vertical axis and horizontal axis are unified.Generally speaking,the trend of geothermal change in the four directions is similar,but there are obvious anomalies in data for a period of time,and the magnitude of anomalies in different directions is different.After on-site investigation,the hot water pipe near the well was broken and hot water spilled.By analyzing the anomalous amplitude in the four directions,we can get the approximate direction of the overflow hot water nearby.Based on this,the fourdirection(five-direction)temperature sensors of East,South,West,North can be placed in each observation well in the future when the geotemperature devices are set up,and these geotemperature monitoring points are best in banded or annular distribution surrounding the fracture zone.Through quantitative analysis of abnormal amplitude in various directions,the azimuth of abnormal heat source is obtained,and the directional intersection can be obtained.The anomalous heat source is under the area near the point.It is very helpful for earthquake early warning to determine the location of friction and compression heat generated by underground structures during the forepart of earthquakes.Finally,the geothermal data of Xichang Xiaojiang Fault Zone and the experimentation area in Huailai have been obtained.Combined with seismic information in recent years,these data can be used to study the relationship between geotemperature and earthquake,and the validity of the geothermal observation and observation methods in the experimentation area can be verified.The geotemperature of 12 m depth in Xichang and the depth of 4 m in Huailai is decomposed by wavelet details respectively.The geothermal figure of the information without tendency can be obtained,and the historical earthquake is corresponding to the abnormal part of the high frequency.