Evidence for diurnal periodicity of earthquakes from midnight to daybreak

作     者：Jinlai Hao Jinhai Zhang Zhenxing Yao 

作者机构：Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences 

出 版 物：《National Science Review》 (国家科学评论(英文版))

年 卷 期：2019年第6卷第5期

页      面：1016-1023页

核心收录：

学科分类：070801[理学-固体地球物理学] 07[理学] 0708[理学-地球物理学] 

基　　金：support from the Strategic Priority Research Program of Chinese Academy of Sciences(XDA17010404,XDA15011700) the National Major Project of China(2017ZX05008-007) the National Natural Science Foundation of China(41574058)for support the Foundation for Excellent Member of the Youth Innovation Promotion Association,Chinese Academy of Sciences(2016) 

主　　题：periodicity of earthquakes time-frequency analyses ocean tide earth tide Local Mean Time 

摘      要：Previously, inadequate earthquake catalogs and the lack of method made it challenging, if not impossible, to determine the dominant period of earthquake *** the advent of densely distributed seismic stations in Japan since 2002, 410 642 M1.0+ earthquakes have been cataloged under the mainland within30-km depth, which provide a superb dataset to identify the periodicity of *** processed this catalog using time-frequency analyses and daily stacking, which are powerful in extracting weak periodical signal from strong random *** concentrated on the time sector from 0:00 to 6:00(*** midnight to daybreak), which is a reliable time window for much higher detectability of weak earthquakes,since it has the lowest affects from cultural *** successfully observed two apparent periodicities of12-and 24-hour, which are much smaller than the fortnightly periodicity presented previously in the *** earth tides, after intentionally ignoring the contribution from the Moon, present similar dominant periods as the *** may indicate that the dominant period of earthquakes is statistically associated with the Sun rather than the *** daily stacking number of earthquakes using a15-minute or 1-hour interval shows a peak around 1:30, rather than usually expected 3:00 to 4:*** addition, bigger earthquakes show more evident variations in the stacking results, and the trend is very consistent for various lower limits of earthquake magnitude from M1.0 to *** discoveries settled the disputes on the existence of the periodicity of earthquakes since 1886 and may open a window to unravel the mystery of earthquakes.