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4. Electromagnetic
monitoring of geodynamic processes
The basic feature of the variant EМ monitoring, developed in laboratory, consists
in reception simultaneous information on EМ field of an internal (geodynamic) origin in
observable magnetotelluric (MT) magnetovariation
(MV) field and on MT and MV transfer functions. With the purpose of precise
separation of EМ field
of an internal origin an algorithm of damping of external EМ field is developed. It is based on
use of linear relation between components of this field. So, for example,
electric component of magnetotelluric field in a
point of observation is related to variations of a magnetic field by formula:
.files/image016.gif)
Here .files/image017.gif) -
variations of component of EМ fields. .files/image018.gif) - pulse transients of elements of impedance matrix Z. .files/image019.gif) - the
residual field describing contribution of EМ fields of an internal origin. Before statement
of monitoring .files/image020.gif) are
defined. Further with the help of found .files/image021.gif) and .files/image022.gif) and observable variations of a
magnetic field .files/image023.gif) the the synthesized electric field .files/image024.gif) is
calculated. Then in the assumption that vary considerably more slowly than
variations of field a residual field .files/image026.gif) is defined. On the basis of
application of adaptive algorithm of definition of pulse transients and a
residual signal the opportunity of realization of monitoring in quasi-real time
as on residual fields .files/image027.gif) .files/image029.gif) , and
on change in time of transfer functions is realized. This algorithm is realized
in working breadboard computerized measurement complex for magnetotelluric monitoring. With
the help this complex monitoring in seismoactive
areas of Northern
Tien Shan and Caucasus is performed.
The basic publications:
1. B.S.Svetov,
S.D.Karinsky, J.I.Kuksa, V.I.Odintsov. Magnetotelluric monitoring of
geodynamic processes // Physics of the Solid Earth, 1997.N 5.p.36-46.
2. B.S.Svetov,
S.D.Karinskij, Yu. I.Kuksa, and V.I.Odintsov. Magnetotelluric
Monitoring of Geodynamic Processes //. Physics of the Solid
Earth. Vol.33. No.5.1997.pp.372-381.
3. Boris S. Svetov, Sergej D. Karinskij, Yurij I. Kuksa and Vladdimir I. Odintsov. Magnetotelluric
monitoring of geodynamic processes // ANNALI GEOFISICA. VOL. XL, N.2, Marth 1997. pp.435-443.
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