First International Conference on MOLDAVIAN RISKS – FROM ...

<strong>First</strong> <strong>International</strong> <strong>Conference</strong> on MOLDAVIAN RISKS - FROM GLOBAL TO LOCAL SCALE
16-19 May 2012, Bacau, Romania
DEVELOPMENT OF EARTHQUAKE-PRONE AREAS
PATTERN RECOGNITION FROM 1972 TO 2012
A.D. Gvishiani 1 , A.I. Gorshkov 2 , A. A. Soloviev 2
1 Geophysical Center, Russian Academy of Sciences, Moscow, Russia
2 Institute of Earthquake Prediction Theory and Mathematical Geophysics, Russian Academy of
Sciences, Moscow, Russia
Corresponding author: gvi@wdcb.ru
Abstract: Accurate definition of earthquake sources plays a main role in development of
seismic hazard assessment. We present the history of the development and the results of
long-term implementation of an original methodology dedicated to pattern recognition of
earthquake prone areas. The methodology was initiated by the pioneering work by
I.Gelfand, V.Keilis-Borok, E.Rantsman (1972). It was based on the hypothesis, derived
from the observations, that large earthquakes are associated with nodes, specific structures
forming around the intersections of the fault zones. The further development and
implementation of the methodology has been carried out in a close international
cooperation with well known geologists, seismologists and geophysicists, including
M.Caputo and G.Panza (Italy), L.Knopoff and F.Press (USA), A.Cisternas, H. Philip,
C.Weber (France), M.Garcia-Fernandez (Spain). Since 1972 over 150 papers on the
development and testing the methodology in different seismic regions of the world have
been published in Russian and international journals and have been presented at
international conferences. Seismogenic nodes for different target magnitudes have been
recognized in numerous seismic regions worldwide including most part of the Alpine belt
from Pyrenees to Himalaya, South America Andes, California, Kamchatka, Iberian
Peninsula and some others. 86 earthquakes of target magnitudes occurred in the regions
studied with this pattern recognition approach since 1972 up to now. 71 of them took place
within the nodes recognized to be potential sites for strong earthquakes prior to their
occurrence. Note that 22 out of these 71 earthquakes occurred at nodes, where, at the
moment of the recognition, events of target magnitude have been unknown yet. Six postpublication
earthquakes took place at nodes defined by pattern recognition as non potential
sites for target magnitudes. Nine earthquakes happened outside the nodes. This 40 years
implementation provided strong evidences in favor of reliability of the methodology. The
results obtained for the mountain regions encouraged us to extend the methodology to
intraplate regions of moderate seismicity, specifically, the interiors of the Iberian Peninsula
and some areas within the Russian and West-European platforms. The paper describes the
stages of development of pattern recognition of earthquake-prone areas during these 40
years and shows future prospective of the method. Special attention is paid to earthquakeprone
nodes in Romania and Moldova.
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