In order to study the characteristics of crustal deformation around the epicenter before the 2016 M_S6. 4 Menyuan earthquake,the GPS continuous stations of the period from 2010 to 2016 were selected according to the o...In order to study the characteristics of crustal deformation around the epicenter before the 2016 M_S6. 4 Menyuan earthquake,the GPS continuous stations of the period from 2010 to 2016 were selected according to the observation data of the tectonic environment monitoring network in Chinese Mainland. The deformation characteristics of the crust before the earthquake were discussed through inter-station baseline time series analysis and the strain time series analysis in the epicentral region. The results show that a trend turn of the baseline movement state around the epicenter region occurred after 2014,and the movement after 2014 reflects an obvious decreasing trend of compressional deformation.During this period,the stress field energy was in a certain accumulation state. Since the beginning of 2014,the EW-component linear strain and surface strain rate weakened gradually before the earthquake. It shows that there was an obvious deformation deficit at the epicentral area in the past two years,which indicates that the region accumulated a high degree of strain energy before the earthquake. Therefore,there was a significant background change in the area before the earthquake. The results of the study can provide basic research data for understanding the seismogenic process and mechanism of this earthquake.展开更多
In this paper,the average dose level is introduced in an environment and area when BEPCⅡis debugged. The typical dose graphs are offered when the electronic storage ring is debugged and works in the synchrotron radia...In this paper,the average dose level is introduced in an environment and area when BEPCⅡis debugged. The typical dose graphs are offered when the electronic storage ring is debugged and works in the synchrotron radiation mode.At the same time,some suggestions about radiation protection are presented.All the data indicate that the main and local part shielding satisfy the need and attain the design target.展开更多
基金funded by the Earthquake Science and Technology Development Fund of GEA(Grant No.2016M02,2016Y02)the Earthquake Tracking Task of CEA(2017010221)+1 种基金the Fund of Science for Earthquake Resilience,CEA,(XH16038Y,XH14049)Grant of National Natural Science Foundation of China(51408567,41304048)
文摘In order to study the characteristics of crustal deformation around the epicenter before the 2016 M_S6. 4 Menyuan earthquake,the GPS continuous stations of the period from 2010 to 2016 were selected according to the observation data of the tectonic environment monitoring network in Chinese Mainland. The deformation characteristics of the crust before the earthquake were discussed through inter-station baseline time series analysis and the strain time series analysis in the epicentral region. The results show that a trend turn of the baseline movement state around the epicenter region occurred after 2014,and the movement after 2014 reflects an obvious decreasing trend of compressional deformation.During this period,the stress field energy was in a certain accumulation state. Since the beginning of 2014,the EW-component linear strain and surface strain rate weakened gradually before the earthquake. It shows that there was an obvious deformation deficit at the epicentral area in the past two years,which indicates that the region accumulated a high degree of strain energy before the earthquake. Therefore,there was a significant background change in the area before the earthquake. The results of the study can provide basic research data for understanding the seismogenic process and mechanism of this earthquake.
文摘In this paper,the average dose level is introduced in an environment and area when BEPCⅡis debugged. The typical dose graphs are offered when the electronic storage ring is debugged and works in the synchrotron radiation mode.At the same time,some suggestions about radiation protection are presented.All the data indicate that the main and local part shielding satisfy the need and attain the design target.
