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Proceedings of the International Conference on
Advances and New Challenges in Earthquake
Engineering Research, Hong Kong Volume
THE REAL-TIME EARTHQUAKE INFORMATION SYSTEM
IN THE NORTHERN KYUSHU, JAPAN WITH A SMALL
SCALE GEOINFORMATION DATABASE FOR SEISMIC
INTENSITY ESTIMATION
Hidemori Narahashi
Assoc. Professor
Department of Architecture
Kyushu Sangyo University, Japan
ABSTRACT
The system to estimate seismic intensity distribution quickly after earthquakes has been
developed since 1999, regarding to a local densely populated area of 20x20 square miles in
the northern Kyushu, Japan. It is called KSU Real Time Earthquake Information System. The
system consists of two subsystems, those are the seismic observation and data acquisition
subsystem and seismic intensity estimation subsystem. In this paper the performance and
goals of the system are outlined and matters to be improved are discussed.
The two properly oriented observation stations and the eight K-NET stations are deployed in
the area to observe three components ground acceleration for twenty-four hours. Soon after
two or more stations will have been triggered with an event the center collects data from the
other stations via public telephone line. It takes about forty minutes to receive a data set from
all of the stations. Since April 2002 additional seismic intensity data at the 108 stations of
Fukuoka Prefecture are transferred very promptly via ISDN telephone line to the data
acquisition subsystem.
After the data acquisition subsystem receives a data set from the ten ground motion
observation stations it is about fifteen minutes until the latter subsystem estimates earthquake
ground motion for more than ten thousands of blocks of 250x250 square meters in the area.
The topography of each block is assigned on the GIS database of this subsystem in order to
estimate JMA seismic intensity based on the data from triggered observation stations.
Eventually the system gives 16 times as dense seismic intensity estimation results than the
DIS system of the National Land Agency, Japan.
The system is characterized as an earthquake information system for the local governments of
the area. The procedures for interpolating the base rock motion from not too many ground
surface data, as well as the procedure for evaluating ground motion amplification effect with
the surface topography, should be improved for practical use. In addition, the third subsystem
should be prepared to open the simulated results for local governments and the community of
The area.