open access

https://hdl.handle.net/2115/97463

Ionospheric changes immediately before the 2008 Wenchuan earthquake

英語

Scaling law

2024-05-01

Elsevier

Advances in Space Research

73(9)

4539-4545

Ionospheric disturbances associated with large earthquakes can be observed with global navigation satellite system (GNSS) receivers on the ground as changes in total electron content (TEC). In addition to coseismic disturbances 10 min after earthquakes caused by acoustic-gravity waves from epicenters, there have been reports on changes immediately before very large earthquakes. We show such disturbances for the 2008 Wenchuan earthquake (M w 7.9), China, started 37 min before the main shock and reached 5 percent of the background value. The results of past 20 cases with Mw 7.3 or more exhibit simple relationships that the leading times scale with fault lengths and the intensities of the anomalies relative to the backgrounds scale with fault areas. We demonstrate that the anomaly imme- diately before the 2008 Wenchuan earthquake fits well with these trends but with slightly longer leading time and stronger intensity. Ó 2024 COSPAR. Published by Elsevier B.V. All rights reserved.

学術雑誌論文

Accepted Manuscript

Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International

© 2024. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/

0273-1177

BA00878857