The paper describes results of studying effects of total electron content (TEC) variations triggered by the Chelyabinsk meteoroid airburst as inferred from unique data of a dense GPS network located around the final part of the meteoroid atmospheric path. Well‐pronounced TEC disturbances with an average period of about 10 min and amplitude of 0.07–0.5 TECU (total electron content unit, 1 TECU = 1016 el m−2) were detected. These disturbances were initiated by an ionospheric source activated about 5–6 min after the airburst. The disturbance velocity damping with time and distance from the airburst was revealed using a GPS interferometric technique. Several modes of TEC disturbances with propagation velocities ranging from 250 to 660 m/s were distinguished through the distance‐time diagram analysis. The estimated position of ionospheric source of TEC disturbances is shifted 36 km southwestward from the airburst, which is most likely to be associated with the conjoint influence of TEC data errors, damping and anisotropy of TID propagation velocity.

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Terra Nova, 24, 295–300, 2012 Abstract We present the first analysis on the crustal deformation in the Korean peninsula by the 2011 Tohoku earthquake. The great Mw 9.0 earthquake extended the Korean peninsula along E–W direction even though it is at a distance longer than one thousand kilometres from the epicentre. The coseismic surface displacements from 1.0 cm (in the southwestern part) to 5.4 cm (in the eastern part) were detected by continuous GPS observation. The estimated coseismic strains from the displacements correspond to approximately 6–28 years of accumulated strains in the Korean peninsula. The postseismic displacements during 162 days after the earthquake showed 43–48% of the coseismic displacements. The results imply that the contractional strains of the Korean peninsula have been accumulated by the locked subduction zone off, and a part of accumulated strains has been released by the mainshock and the afterslip of the 2011 Tohoku earthquake.