Solar quiet daily variation(Sq)are dependent on local time.Herein,we applied the moving superposition method to separate the Sq component of correction observatory data and performed a time diff erence correction on t...Solar quiet daily variation(Sq)are dependent on local time.Herein,we applied the moving superposition method to separate the Sq component of correction observatory data and performed a time diff erence correction on the Sq component according to the longitudinal diff erence between the correction observatory and the field station while maintaining the time of other data components.The data were then reconstructed and used for diurnal-variation correction to improve the accuracy of the daily variations correction resu;lts The moving superposition method employs data of“nonmagnetic disturbance days”obtained 15 d before and after to perform the superposing average calculation on a daily basis,aiming to obtain the Sq of continuous morphological changes.The effect of longitude correction was tested using the observatory record and field survey data.The average correction distance of the test observatories was 2114 km,and the correction accuracies of the H(horizontal component of geomagnetic field),D(geomagnetic declination),and Z(vertical component of geomagnetic field)were improved by 28.4%,45.0%,and 21.7%,respectively;the average correction distance of the field stations was 2130 km,and the correction accuracies of the F(geomagnetic total intensity),D,I(geomagnetic inclination)components were improved by 35.2%,26.7%,and 13.9%,respectively.The test results also demonstrated that the longitude correction eff ect was greater with an increased correction distance.展开更多
A three-component geomagnetic survey was carried out during the period from 2002 to 2004 in China including Jiujiang-Ruichang region. Comparing the ＂2005.0 surface spline model of China geomagnetic field＂ created on...A three-component geomagnetic survey was carried out during the period from 2002 to 2004 in China including Jiujiang-Ruichang region. Comparing the ＂2005.0 surface spline model of China geomagnetic field＂ created on the basis of the survey data with the ＂1970.0 surface spline model of China geomagnetic field＂, we can see an obvious abnormity in the geomagnetic horizontal component within a range of about 100 km around the epicenter of the Ms=5.7 Jiujiang-Ruichang earthquake occurred on November 26, 2005. After the earthquake, we carded out a repeated geomagnetic survey at 21 stations in the Jiujiang-Ruichang region and created a corresponding ＂2005.0 partially revised surface spline model of China geomagnetic field＂. By comparing the above three models, analyzing the geomagnetic horizontal component at the profile in the Jiujiang-Ruichang region and quantitatively studying the geomagnetic data of every stations around the Ms=5.7 earthquake, we have obtained the geomagnetic abnormity associated with this earthquake. Then the geomagnetic abnormity and its relation with seismic activity are discussed in this paper.展开更多
基金supported by The Earthquake Science and Technology Program of Hebei Province (Grant Number DZ20190422046).
文摘Solar quiet daily variation(Sq)are dependent on local time.Herein,we applied the moving superposition method to separate the Sq component of correction observatory data and performed a time diff erence correction on the Sq component according to the longitudinal diff erence between the correction observatory and the field station while maintaining the time of other data components.The data were then reconstructed and used for diurnal-variation correction to improve the accuracy of the daily variations correction resu;lts The moving superposition method employs data of“nonmagnetic disturbance days”obtained 15 d before and after to perform the superposing average calculation on a daily basis,aiming to obtain the Sq of continuous morphological changes.The effect of longitude correction was tested using the observatory record and field survey data.The average correction distance of the test observatories was 2114 km,and the correction accuracies of the H(horizontal component of geomagnetic field),D(geomagnetic declination),and Z(vertical component of geomagnetic field)were improved by 28.4%,45.0%,and 21.7%,respectively;the average correction distance of the field stations was 2130 km,and the correction accuracies of the F(geomagnetic total intensity),D,I(geomagnetic inclination)components were improved by 35.2%,26.7%,and 13.9%,respectively.The test results also demonstrated that the longitude correction eff ect was greater with an increased correction distance.
文摘A three-component geomagnetic survey was carried out during the period from 2002 to 2004 in China including Jiujiang-Ruichang region. Comparing the ＂2005.0 surface spline model of China geomagnetic field＂ created on the basis of the survey data with the ＂1970.0 surface spline model of China geomagnetic field＂, we can see an obvious abnormity in the geomagnetic horizontal component within a range of about 100 km around the epicenter of the Ms=5.7 Jiujiang-Ruichang earthquake occurred on November 26, 2005. After the earthquake, we carded out a repeated geomagnetic survey at 21 stations in the Jiujiang-Ruichang region and created a corresponding ＂2005.0 partially revised surface spline model of China geomagnetic field＂. By comparing the above three models, analyzing the geomagnetic horizontal component at the profile in the Jiujiang-Ruichang region and quantitatively studying the geomagnetic data of every stations around the Ms=5.7 earthquake, we have obtained the geomagnetic abnormity associated with this earthquake. Then the geomagnetic abnormity and its relation with seismic activity are discussed in this paper.
