The Volcanic Hazard Mapping theme (1995-2001) was undertaken as part of the GARS Asiaproject and was initiated to address the global concern of natural hazards of geologic origin through volcanic hazard mapping of lahar flows (mudflows).

Lahars are powerful forces capable of moving great quantities of material over long distances in a short space of time, destroying virtually everything in their path. The result of a lahar flow is usually a deposit of sediment that can range from a few meters to a few hundreds of meters in thickness.

Objective of the Volcanic Hazard Mapping theme

The main objective of the Volcanic Hazard Mapping theme was to develop a new methodology in volcanic hazard mapping using optical, thermal and Synthetic Aperture Radar (SAR) data and Geographic Information System (GIS) technology.

Aim of the theme

The aim of the volcanic hazard mapping theme was to identify old lahar flows using the integration of data from passive and active sensors in order to evaluate the risk of developing new lahar flows on the volcano.

©Jean-Louis Cheminee

Test Sites Bulusan, Mayon, Pinatubo and Taal volcanoes in the Philippines The research was primarily carried out on the Pinatubo volcano as a consequence of its eruption in 1991.

Methodology

Physical characteristics were measured at each of the volcanoes to generate a comprehensive reference database of volcano characteristics. Measurements were made on :

• Volcano structure
• Active fault zones
• Morphology
• Drainage patterns
• Extent of major volcanic and volcanoclastic deposits
  
  The database was used to carry out specific research on
• Risk zonation studies (Bulusan)
• Survey of the flanks of the volcano edifice prone to sector-collapse (Mayon)
• Distribution of different generations of lahar deposits within distalluvial fans (Pinatubo)
• Survey of ground deformation using SAR data (Taal)
• Survey of thermal anomalies using airborne remote sensing data (Taal)

Results

For scientific results, please visit: IUGS, ITC, MRAC and PHIVOLCS.

International Collaboration

Philippine Institute of Volcanology and Seismology (PHIVOLCS), Philippines
Musee Royal de l'Afrique Centrale (MRAC), Belgium
Universite de Paris-VI, France
Bundesanstalt fur Geowissenshaften und Rohstoffe (BGR), Germany
International Institute for Aerospace Survey and Earth Sciences (ITC), Netherlands
University of Cambridge, U.K.