SEISMIC MONITORING OF STRONG EARTHQUAKES SOURCE AREAS
A. Lutikov
Geophysical Survey of RAS, Russia
Physically justified choice of seismological parameters for seismic situation monitoring
directed to strong earthquakes precursors finding is based on the supposition, that the stress
upbuilding process during the strong earthquake preparation leads to simultaneous changes in
seism tectonic deformation process.
In this way the introducing of seism tectonic deformation concept is very important. It is
based on the submission that the earthquake is a result of elastic deformations release
accumulated owing to slow earth's interior movements. So to the earthquake responds some
contribution to this movement. For this contribution determining such source parameters as focal
mechanism and value of displacement are used [Yunga, 1990].
The rate of seism tectonic deformation (*ij) is
k= K
*ij = 1/ (VT) mij(k) M0(k)N(k)
(1)
k=1
Where  is shift module, V is containing volume, T is time interval, M0(k) is scalar seismic of
the earthquakes in volume V for time interval T in k-th magnitude range, N(k) is number of
earthquakes in k-th magnitude range (k=1,2,…K),
mij(k) = (ainj + aj ni) (k) / 2D(k)
(2),
here a is the displacement change on selected surface of the separated fault, n is normal vector,
D is average fault displacement; corner brakes means the average value by k-th magnitude
range. Matrix mij(k) is of unite intensity.
The scalar analog of expression (1) is
k=K
* = 1/ (VT) (k) M0(k)N(k)
(3)
k=1
Parameter  (01) is called as order coefficient or ordering index; in general way it slightly
depends on magnitude and is considered as a chaotic measure of seismic process [Yunga, 1990;
Lutikov, 1999, Lutikov, 2002a].
It is possible to introduce ordering index (k) в k-th magnitude range as the ratio of average by
the sampling seismic moment tensor matrix norm M(k)ij  to the average by this sampling
seismic moment tensor matrix norm M(k)ij. So
(k) = M(k)ij  / M(k)ij
(4)
Included in the formula (3) parameters -  M0(k) и  - are in the independent concern, as
characterize the different sides of the seismic process.
Scalar seismic moment time series in strong earthquakes source areas give the
opportunity to trace by the level of background seismicity the stages of activization and seismic
quiescence - one of the important seismic precursors of strong earthquakes [Sobolev, 1993] and
are rather reliable to its detecting [Lutikov, Kuchay, 1998].
In turn, the time series of ordering index  demonstrate natural shift of order and
chaotization phases of the seismic process in time, related with originating of strong earthquakes.
Usage of parameter  for seismic situation analysis in the areas of strong earthquakes occurrence
responds a hypothesis about the determined chaos and selforganizing of the tectonic process or
Self-organized Criticality [Turcotte, 1999].
Ordering Index was used with the aim of retrospective seismic situation analysis in the
source areas a number of strong earthquakes for the last decade in different regions of the World:
Shikotan (near South Kuriles), 04.10.1994, Mw=8.3; Kronotskoye (near East coast of
Kamchatka), 05.12.1997, Mw=7.8; Taiwan, 20.09.1999, Mw=7.7; near the coast of New Britain,
04.06.2000, Mw=7.9; near West Coast of Peru, 23.06.2001, Mw=8.2. Besides it Tien Shan region
was chosen as an example of continental area - here Susamir Earthquake in Kirghizia,
19.08.1992, Mw=7.3, was considered [Lutikov, 2002b].
1.2
8
7.5
1
7
0.8

6.5
0.6
6
0.4
5.5
K
0.2
5
0
1977
1980
1983
1986
1989
T, years
1992
1995
1998
4.5
2001
Kav
Kav-s
Kav+s
Mw max
Mw m.e.
Parameter's  temporal dependence in Kronotskoye EQ, 05.12.1997, source area.
For example, parameter's  temporal dependence in Kronotskoye EQ source area is
shown in the picture.
Practically in all the cases considered the strong earthquake arises on a background of
sharp ascending of parameter , to which one will precede its deep minimum. On the basis of
comparing the results of analysis for all these earthquakes, it is possible to make conclusion that
the phenomenon detected wears global nature.
The paper is fulfilled at the support of fund RFBR, grants 02-05-64433, 04-05-64826 and
fundamental program № 5 ONZ of RAS.
Reference
1. Lutikov A.I. Elements of Tien Shan seismic mode in terms of seism tectonic deformation. //
Materialy Vserossiyskoy shkoly-seminara «Geomorphology of Mountains and Forelands».
Barnaul - Gorno-Altaisk, September, 24-30, 2002a, pp. 172-179.
2. Lutikov A., Kuchay M.S. Seismicity time variation in the areas of occurense a number of
strong earthquakes in the North Caucasus. //1998. Journal of earthquake prediction research.
V.7, No.1, pp.76-82.
3. Lutikov A. Seismicity monitoring of six strong earthquakes source areas (1976-2001) by one
seismic moment tensor invariant in different regions of the world. // Europian Geo-physical
Society. 27th General Assembly. Geophysical Research Abstracts. 2002b, V.4, CD.
4. Sobolev G.A., 1993, The foundations of earthquake prediction. // Moscow, Nauka, 313 pp.
(rus)
5. Turcotte D.L. Seismicity and self-organized criticality. Physics of the Earth and Planetary
Interiors, 111, 1999, pp. 275–293.
6. Yunga S.L. // 1990, Methods and results of studies of seismotectonic deformations.
Moscow, Nauka, 191 pp. (rus)