Seismic instruments: article

CONSTRUCTION OF THE AVERAGE CURVE OF THE SEISMIC VELOCITY OF THE EARTH'S CRUST IN THE TERRITORY OF ARMENIA, BASED ON THE DATA OF PROFILE SEISMIC OBSERVATIONS
V.Y. BURMIN1
A.M. AVETISYAN2
J.K. KARAPETYAN2
A.O. OGANESYAN2
1 Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences
2 Institute of Geophysics and Engineering Seismology named after Academician A. Nazarov NAS of RA
Journal: Seismic instruments
Tome: 57
Number: 3
Year: 2021
Pages: 19-28
UDK: 550.311
DOI: 10.21455/si2021.3-2
Аnnotation file
Bibliographic list
Keywords: hodograph, velocity model of the Earth's crust, Armenia, profile seismic observations, method of converted waves from earthquakes, deep seismic sounding
Аnnotation: To determine the coordinates of earthquakes, the RA Seismic Service uses algorithms based on the Geiger method. All these algorithms use only one hodograph (one velocity curve) for the entire study area and for all stations of the RA seismological network. Despite the fact that a number of works have been devoted to the structure of the earth's crust and the upper mantle of the Caucasus and, in particular, the RA, however, so far most of the existing travel time curves do not allow determining the coordinates of earthquake hypocenters and, in particular, the depth of the source with sufficient accuracy. It is quite obvious that to determine the coordinates of earthquakes, it is desirable for the Earth's crust to have hodographs (or velocity columns) constructed not according to data from local earthquakes, but according to other seismological data, in particular, according to the data of deep seismic sounding, the method of converted waves from earthquakes, and for the upper mantle according to data from distant earthquakes. Currently, information has been collected on the velocities of longitudinal waves in the crust within the territory of Armenia, which makes it possible to present an averaged velocity model of the earth's crust in Armenia. For this, the data of all available velocity sections were used, compiled on the basis of materials obtained along the network of regional profiles by the method of converted waves from earthquakes and data of deep seismic sounding. The speed curve was built on the basis of the data of the DSS and MOVZ obtained in different years in the territory of Armenia. The use of one velocity curve by the seismological networks in Armenia will allow obtaining homogeneous data obtained by these networks.