Specialization: 010700/07 Physics of the Earth and planets
Program: 42 Seismology
Program manager: Prof.. T.B. Yanovskaya
Earth’s physics department
Supervisor: Prof. T.B. Yanovskaya
Referee: Dr. E.L. Lyskova
Effect of earthquakes on the cross-correlation function of ambient seismic
noise
Vera Emtceva
Сorrelated component of noise is composed of surface waves generated by sources distributed
over the Earth’s surface more or less uniformly. In such a case the cross-correlation function
(CCF) at two stations may be considered as the Green’s function of surface wave. An analysis
of both CCF at two stations and earthquake epicenter density shows that if the time interval
used for calculation of CCF is characterized by strong increase of seismicity in a small size
area aside from the line going through two stations, the CCF is distorted, and as consequence
it is impossible to construct a dispersion curve. The methods for reducing the distortion of
CCF are described.
The records of Z-component of noise at the West European and East European stations were
used to obtain dispersion curves of Rayleigh waves using the methods for correction of CCF.
Averaged dispersion curves at both sides from the Tesseire-Tornquist Line were used to
estimate the structure of the crust and upper mantle in the East and West Europe. The S-wave
velocity in crust and upper mantle lid up to 200 km depth to the west of the TTL is found to
be lower than that to the east of TTL, while at the depths exceeding 200 km it turns to be
higher.
The list of the publications
1. V.V. Emtceva, T.Y. Koroleva. Detervination of upper mantle velocity structure by the
noise surface wave tomography accounting influence of earthquake // Geophysical
research methods for Earth and the bowels of the earth, 2012. (submitted)
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