International Archives of Photogrammetry and Remote Sensing. Vol. XXXII Part 7C2, UNISPACE III, Vienna, 1999 
93 
UNISPACE III - ISPRS/EARSeL Workshop on 
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E3 
I5PRS 
‘Remote Sensing for the Detection, Monitoring 
and Mitigation of Natural Disasters ” 
2:30-5:30 pm, 22 July 1999, VIC Room B 
Vienna, Austria 
SPACE TECHNOLOGY AND EARTHQUAKE HAZARD MANAGEMENT 
J. Béquignon 
European Space Agency 
Via Galileo Galilei, 1-00044 Frascati - ITALY 
Jerome.Bequignon@esrin.esa.it 
ABSTRACT 
The hidden nature of earthquakes, taking place at depth varying from 1 to hundreds of kilometres, the extreme conditions governing 
the phenomenon, its rheology both in terms of time and space, make progress of the research difficult. Space technology does 
contribute to the scientific research and to general measures in earthquake management, sometimes in unexpected ways such as with 
SAR interferometry, but it cannot provide a magic answer beyond physics. This presentation intends to review the contributions of 
space techniques along the 3 main phases of the management of earthquake hazards. 
Most earthquakes occur in well-known areas and while this is still a difficult task, risk maps and vulnerability maps may be drawn. In 
this context, satellite imagery is used effectively for land use or urban management, and this usage will certainly increase with very 
high resolution imaging systems. Imaging systems are also used at a larger scale for detecting tectonic lineaments and structures. 
However structural characterisation of buildings has still to be performed by means of traditional surveys. 
Accurate positioning systems, involving laser tracking, and VLBI have been used for a long time. Nowadays, dense networks of GPS 
systems equip areas such as the Los Angeles basin. Such systems, and the novel technique of differential SAR interferometry, allow 
for measuring accurately ground deformation, aseismic displacements and plate motion rate along active faults such as the North- 
Anatolian fault. These data may be integrated with other geophysical measurements in order to assess stress loading. 
Various phenomena, such as electromagnetic, thermal or seismic anomalies, have been quoted as possible precursors of large 
earthquakes, and some experiments with imaging systems operating in the thermal band are found in the literature. Dedicated satellite 
missions are planned for electrical anomaly tracking. For the time being these are research issues which have not met a general 
acceptance nor are systematically used. 
The next generation of satellite mobile phones provides telecommunication means virtually independent of terrestrial lines and 
relays, which should be particularly appropriate after an earthquake occurs. 
Current imaging systems have shown limitations in terms of resolution for mapping effectively damaged areas, as in the case of Kobe 
or Spitak. The next generation of 1-m optical systems may provide a suitable resolution but revisit time may be a serious issue. Again 
SAR interferometry may be used effectively to map surface deformations, when this method will be completely robust. Assessment 
of structural damage to buildings is probably beyond: the capabilities of even the very high resolution optical systems although some 
research with. SAR polarised instruments have shown some potential. 
Management of earthquake hazard is a very difficult task. In most phases, current space technologies may contribute to it, together 
with other methods. Some new satellite systems will deliver more appropriate information and others will continue to contribute to 
the necessary basic research. 
Space technology and earthquake 
hazard management 
J. Béquignon 
European Space Agency 
Jerome.Bequignon@esrin.esa.it 
22 July 1999 
§esa, 
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