REDUCING EARTHQUAKE LOSSES
IN THE SOUTH ASIAN REGION (RELSAR)

Ø Seismicity of the Asian region
Ø RELSAR programme
Ø RELSAR meetings

Seismicity of the Asian region
The Asia region has the highest level of seismicity on the planet. It is also the setting for many of the largest earthquakes. The high seismic risk in the region was recently emphasized by the September 1999 magnitude 7.4 earthquake in central Taiwan that caused more than 1,000 deaths and billions of U.S. dollars in damage and by the 26 January 2001 magnitude 7.5 Bhuj earthquake in India. The majority of earthquakes in the Asia region are related to regions of plate convergence where one tectonic plate slides beneath another plate (subduction zones). In addition to generating large earthquakes, plate subduction often gives rise to volcanism. However, large earthquakes are not always associated with subduction zones. Faults where horizontal motion takes place (strike-slip faults) also generate devastating earthquakes. Strike-slip faults in China and Mongolia are responsible for numerous destructive earthquakes, often with magnitudes between 6.0 and 7.5 and occasionally greater than 8.0.

In response to this risk, most nations have increased the number and quality of seismic stations used to monitor earthquake activity. The optimal use of these data for regional earthquake monitoring is a major challenge that will require the exchange of data, software, and expertise among the interested nations.

RELSAR programme
Since 1993, the U.S. Geological Survey (USGS) and the United Nations Educational, Scientific and Cultural Organization (UNESCO) have been cooperating with eastern Mediterranean region earth science organizations under the program for the Reduction of Earthquake Losses in the Eastern Mediterranean Region (RELEMR). Countries from the western Mediterranean region have also participated. The European?Mediterranean Seismological Center (EMSC) has coordinated the exchange of data among Eastern Mediterranean countries. Since 1996, the Lawrence Livermore National Laboratory (LLNL) has also been cooperating in the program.

To discuss issues related to seismicity, seismic hazards, magnitude calibration, broadband data, the CTBT, and the interest in and need for a RELEMR-type program for Asia, a workshop was held at Clark Air Base, Pampanga, the Philippines, 5-7 December 1999. The workshop was hosted by the Philippine Institute of Volcanology and Seismology (PHIVOLCS) and sponsored by UNESCO. To focus on the high risk Himalayan region, UNESCO, the USGS, the Nepal Department of Mines and Geology, and the Nepal Geological Society organized a workshop on Seismic Analysis in the South Asia Region in Kathmandu, Nepal, 10-13 September 2001 and the Second International Workshop on Seismic Analysis in the South Asia Region was organized by the China Seismological Bureau (CSB), UNESCO, and the USGS and held in Kunming, China, 20-23 May 2002. As a follow-on to the Kathmandu-2001 and the Kunming-2002 workshops, the Third International Workshop on Seismic Analysis in the South Asia Region was organized by the Sri Lankan Geological Survey and Mines Bureau (GSMB), UNESCO, and the USGS.

RELSAR meetings

• " 5th International workshop on Seismic Analysis in the South Asia Region, Xi'an, China, 12-15 November 2005.
• " Fourth International Workshop on Seismic Analysis in the South Asia Region, Dakha, Bangladesh, 12-15 September 2004.
• " Third International Workshop on Seismic Analysis in the South Asia Region. Colombo, Sri Lanka, 30 September - 3 October 2003.
• " International Workshop on Future Cooperative Activities in the South Asia Region, Kathmandu, Nepal, 23 November 2002.
• " Second International Workshop on Seismic Analysis in the South Asia Region, Kunming, China, May 2002.
• " International Workshop on Seismic Analysis in the South Asia Region, Kathmandu, Nepal, 10-14 September 2001.

Next meeting

• 6th International Workshop on Seismic Analysis, Chiang Mai, Thailand, 4-7 December 2006