1. Key Laboratory of Intraplate Volcanoes and Earthquakes (China University of Geosciences, Beijing), Ministry of Education, Beijing 100083, China and China University of Geosciences, School of Geophysics and Information Technology, Beijing, China.
2. Key Laboratory of Intraplate Volcanoes and Earthquakes (China University of Geosciences, Beijing), Ministry of Education, Beijing 100083, China and China University of Geosciences, School of Geophysics and Information Technology, Beijing, China. (corresponding author)