Electromagnetic monitoring network of the Northern Tien Shan
Creation of the permanent network of multi-parametric electromagnetic monitoring for seismically active zones of the Northern Tien Shan in frequency range from 0.1 Hz to 1 MHz
Tech Area / Field
- ENV-SEM/Seismic Monitoring/Environment
3 Approved without Funding
Institute of Geology of NAS of Kyrgyzstan Republic, Kyrgyzstan, Bishkek
- Kyrgyz-Russian Slavonic University, Kyrgyzstan, Bishkek
- KRISS - Korea Research Institute of Standards and Science, Korea, Taejeon\nUniversity of Cologne / Institute of Geophysics and Meteorology, Germany, Köln\nUniversity of Athens / University of Athens, Physics Department, Nuclear and Particle Physics Section, Greece, Athens\nUniversitat de Barcelona / Dept. Geodinamica i Geofisica, Spain, Barcelona\nUniversity of Electro-Communications, Japan, Tokyo\nWright State University, USA, OH, Dayton
Project summaryThe ground electromagnetic observations are one of the most important methods for seismic activity monitoring and earthquake prediction. Electromagnetic precursors are the most sensitive indicators of the stress-strain state of rocks compare with other earthquake precursors (seismic, geodeformation, geochemical, geothermal, hydrogeological, etc.), and they are promising in terms of solving the important task of short-term earthquake prediction.
In the last 10–15 years there has been significant progress in the study of seismo-electromagnetic phenomena. This is primarily because of the development of recording hardware and software tools and the use of the latest achievements of electronics and computer technology in modern equipment with the ability to accumulate and operationally process large amounts of experimental data. New generations of equipment have made it possible to increase significantly the reliability and accuracy of measurements. New results on the recording of electromagnetic precursors in various earthquake-prone areas of the world have been obtained.
The electromagnetic monitoring network in the Bishkek prediction site the creation of which is planned in the framework of this project will ensure the registration of such earthquake precursors as rocks resistivity, electrotelluric anomalies, electromagnetic emission and ionosphere disturbances. This set of precursors investigated in frequency range of 0.1 Hz – 1 MHz is promising for the short and mid-term earthquake prediction. Instruments of audiomagnetotelluric (AMT) soundings ACF-4M for frequency range 0.1-1000 Hz and radiomagnetotelluric (RMT) soundings RMT-F for frequency range 1-1000 kHz will be used at the monitoring.
The works within the present project are based on results of two previous ISTC projects, fulfilled by executors of the suggested project in the Bishkek and Issyk-Kul prediction sites per previous years. In 2003-2007 within the frameworks of the ISTC project KR-583 “Investigations of seismo-electromagnetic phenomena in the range of extremely low frequencies and creation of the experimental network of AMT-monitoring of seismic activity in the Bishkek prediction test site” the modernization of the receiving equipment of audiomagnetotelluric soundings and software tools for data processing with reference to geological and geophysical features and with account of noise conditions in the Bishkek prediction site was executed. Techniques of the tensosensitive zones selection for the realization of long-term monitoring of seismic activity and the study of rocks resistivity variations were developed. Various approaches to the registration of electromagnetic emission anomalies were tested. Monitoring observations of investigated parameters using the experimental monitoring network were executed. Using the received data the regularities of the electromagnetic field behavior in various frequency intervals of the audio frequency range (1-1000 Hz) were investigated. The intervals of frequencies the measurements in which allow us to receive the most reliable and informative data from the point of view of monitoring of the stress-strain state of rocks were revealed. Software tools for the monitoring data processing for apparent resistivity and electromagnetic emission observations were developed.
In 2011-2013 within the frameworks of the ISTC project KR-1828 “Development of the electromagnetic monitoring technology for seismically active zones of the Northern Tien Shan in frequency range from 0.1 Hz to 1 MHz” the researches for the electromagnetic monitoring technology development in sub-audio, audio (0.1-1000 Hz) and radiofrequency (1-1000 kHz) ranges were carried out. Modernizations of equipment and software tools (extension of the frequency range of the RMT soundings instrument, creation of noiseless magnetic sensors for the registration of electromagnetic emission, completion of software tools for monitoring observations) were executed. The technique of measurement and software tools for the data processing and interpretation in wide frequency range from 0.1 Hz to 1 MHz of such earthquake precursors, as resistivity variations and electromagnetic emission were developed. The researches for the estimation of possibilities of ionosphere effects registration above zones of the earthquakes preparation in audio- and radiofrequency ranges were executed. At the realization of works under the project tensosensitive zones for experimental electromagnetic monitoring researches on the Bishkek and Issyk-Kul prediction sites and their subsequent use at the creation of the permanent monitoring network were selected.
Executed within the frameworks of the ISTC projects KR-583 and KR-1828 investigations of seismo-electromagnetic phenomena and development of the technology allow us to plan the following stage - creation of a permanent network of the electromagnetic monitoring of earthquake precursors in seismically active zones of the Northern Tien Shan.
The main purpose of the project is the creation of permanent network of the multi-parametric electromagnetic monitoring of the stress-strain state of rocks in frequency range from 0.1 Hz to 1 MHz with the registration of rocks resistivity variations, electrotelluric and magnetic field anomalies, electromagnetic emission and ionosphere disturbances for seismically active zones of the Northern Tien Shan.
The following tasks will be solved for accomplishment of the main purpose of the project.
А1: Modernization of the equipment of audio- and radiomagnetotelluric methods for the multi-parametric electromagnetic monitoring on the network of stations in frequency range 0.1 Hz - 1 MHz.
А2: Creation of bunker-type monitoring stations and base monitoring data processing centers in Bishkek and St. Petersburg.
А3: Development of software tools for the monitoring control and data processing in the base centers.
А4: Development of the technology of synchronous registration on the network of stations of rocks resistivity variations, electrotelluric and magnetic field anomalies, electromagnetic emission and ionosphere disturbances.
А5: Development of the technology and software tools for integrated data interpretation of the multi-parametric electromagnetic monitoring on the network of stations.
А6: Creation of the permanent network of multi-parametric electromagnetic monitoring for seismically active zones of the Northern Tien Shan in frequency range 0.1 Hz - 1 MHz, consisting of three bunker type stations with the equipment of the AMT and RMT methods and base data processing centers.
The monitoring of the complex of electromagnetic precursors covers a wide spectrum of frequencies from 0.1 Hz up to 1 MHz, including sub-audio, audio and radiofrequency ranges (ULF, ELF, ILF, VLF, LF, MF ranges). The registration of rocks resistivity variations is based on measurements of natural electromagnetic fields in the audio frequency range from 7 up to 300 Hz. The study of electrotelluric and magnetic field anomalies is fulfilled in sub-audio frequency range 0.1-3 Hz. The monitoring of electromagnetic emission is based on the registration of time series of electric and magnetic fields signals in audio and radiofrequency ranges from 3 Hz up to 1 MHz. At the monitoring of ionosphere earthquake precursor’s data of measurements in radiofrequency range (registration of removed radio transmitter’s signals) and audio frequency range (registration of Schumann resonances of natural electromagnetic field) are used.
At the project realization the results of previous researches on the study of geological and geophysical features of the Bishkek prediction site, investigations of seismo-electromagnetic phenomena and development of the monitoring technology with the reference to conditions of seismically active zones of the Northern Tien Shan zones will be used.
Works under the project will be carried out in close contact with foreign collaborators. Information interchange, joint planning and carrying out of investigations at test and prediction sites, tests of hardware-software complexes and carrying out of scientific seminars will be fulfilled.