Entity

Time filter

Source Type


Rong D.-L.,Lanzhou National Observatory of Geophysics | Rong D.-L.,Lanzhou Base of Institute of Earthquake Science | Li Y.-R.,Lanzhou National Observatory of Geophysics | Li Y.-R.,Lanzhou Base of Institute of Earthquake Science
Earthquake | Year: 2011

In this paper we studied the characteristics of two seismological precursors(seismic spatial correlation length and coda Q c) associated with three moderate-strong earthquakes occurred in Gansu province, China, based on Allegre's scale-rule theory of rock fracture. The results show that an increasing trends of seismic spatial correlation length and coda Q c appeared before the three earthquakes. A power exponent relation is used to fit the increasing variation form of these two parameters. Source


Xie T.,Lanzhou National Observatory of Geophysics | Xie T.,China Earthquake Networks Center | Du X.,Lanzhou National Observatory of Geophysics | Liu J.,Lanzhou National Observatory of Geophysics | And 4 more authors.
Acta Seismologica Sinica | Year: 2013

Wavelet transform technique is applied to the analysis of geo-resistivity data observed at Chengdu and Jiangyou stations before and after Wenchuan MS8.0 earthquake in 2008 and the ionospheric magnetic field recorded by DEMETER satellite before and after the Wenchuan earthquake and the 2010 Haiti earthquake, in order to study the wavelet power spectrum of geo-resistivity and ionospheric magnetic field and its relative variation. Our analysis result suggests that (1) the wavelet power spectrum and its relative variation increased greatly at the times when the geo-resistivity of N58°E channel of Chengdu station displayed its medium-term decrease and short-term increase, the impending anomaly was recorded on the N10°E channel of Jiangyou geo-resistivity station and the wavelet power spectrum of x component of ionospheric magnetic field and its relative value increased distinctly before Wenchuan earthquake, showing typical Earth-space electromagnetic anomaly of geo-resistivity and ionospheric magnetic field; (2) The wavelet power spectrum of x and z components of ionospheric magnetic field and its relative variation also increased greatly before Haiti earthquake, similar to the increase before and after Wenchuan earthquake. Source

Discover hidden collaborations