English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In the present work, phenomena in the iono- sphere are studied, which are connected with earthquakes (16 events) having a depth of less than 50 km and a magnitude M larger than 4. Analysed are night-time Es-spread effects using data of the vertical sounding station Petropavlovsk- Kanchatsky (' = 53:0o, = 158:7o) from May 2004 until August 2004 registered every 15 minutes. It is found that the maximum distance of the earthquake from the sound- ing station, where pre-seismic phenomena are yet observ- able, depends on the magnitude of the earthquake. Further it is shown that 1-2 days before the earthquakes, in the pre- midnight hours, the appearance of Es-spread increases. The reliability of this increase amounts to 0.95. 2 Method of analysis In the present work earthquakes with magnitudes of M > 4:0 and depths of up to 50 km are studied. The investigation of such rather weak earthquakes is reasonable as the sporadic E-layers have only a distance of about h 100 km from the surface of the earth, and the seismo-ionospheric effects are apparently stronger than in the case of the F-layer situated at an altitude of about 300 km.

On Es-spread effects in the ionosphere connected to earthquakes