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A project, named “Earthquake Prediction System Based on Observing the Stress of Rocks by the Method of ULF Electric
Field Measurement” is being carried out at Istanbul Technical University. The aim of this project is to collect
the data of regional rock stress by using electrical measurement methods and analyzing the pattern of this collected
data in order to be able to determine the anomalies related to possible
earthquakes.
The project is also being supported by some other academic and scientific institutions. The study has been planned
in two phases and the first phase is about forecasting the approximate place and time of earthquakes. A data collection
system of 30 stations was started in the Marmara Region. However, earthquake prediction and early warning of earthquakes
are two different stages of the project. If the first phase can be completed and the correlation of collected data and the earthquake
occurrence proves accurate, the second phase, consisting of early warning studies will start.
In order to be able to discuss early warning, the approximate magnitude of possible
earthquakes has to be determined. Even if a successful prediction system is installed in our country, where the
average daily number of earthquakes with a magnitude of bigger than 2,5 is about 4, no success with early warning is
possible unless the magnitude of a possible earthquake is distinguished clearly. In order to be able to consider
the early warning function of the project we must await sufficient data collection. Any suspicious conditions will
also be carefully evaluated throughout the study.
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Depending upon their mineral structure, rocks consist of various quantities of piezoelectric characterized material
such as quartz (SiO2). It is thought that it will be possible to observe piezoelectrically caused changes from
the surface, that occur as a result of an increase in long term stress on the rocks at the fault zones and changes
during the rupture period.
Greek scientists have developed a method called VAN for this purpose but no significant success has been achieved
with it yet. In the VAN method the electrical potential distinction of two points on earth is being measured. Yet,
the electrical characteristics of the earth not only change by seismological effects but also noticeably
change
due to environmental effects such as heat, humidity and pressure.
A digital measuring system, which minimizes the noise component by using a highly sensitive electronic signal processing
method, was developed to be used for the project initiated at Istanbul Technical University. The data of the stations
first around Istanbul and later the whole Marmara Region is being collected at a center and the patterns related
to time and position are being evaluated. The plan is to gradually increase the number of stations
in the Marmara Region
(the area of the study) from 30 at first to 60 eventually.
These types of studies take a long time as the regional mineralogical structure
is varied and the earthquakes do not occur when wanted. A study that will last about 4 years is planned. Even though
the records of the last one year are encouraging, the subject needs to be studied patiently for a longer time in
order to be able to discuss the results of the project.
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