POST-EARTHQUAKE INTERVENTIONS: THE POST-SEISMIC INTERVENTION TEAM

The post-seismic intervention team provides assistance and support to the scientific community interested in studying major earthquakes and the natural processes associated (after-shocks, surface cracks, post-seismic deformation that can be measured in surface area, etc.). Its role is to enable improved coordination of actions to facilitate the field interventions after an earthquake. It also acts as a relay between the scientific community involved in the interventions and the supervisory bodies, particularly the CNRS-INSU.

The team comprises scientists from various French laboratories involved in seismological, geodetic and tectonic studies associated with earthquakes. These scientists are mobilised after a major earthquake, subject to their availability. The team is activated directly by request from French researchers or upon receipt of an earthquake alert message likely to be of interested to the French scientific community. During the crisis, the team helps to collect and assess information, organise actions, publish information, monitor and adjust the actions to be undertaken.

Earthquakes may be classed as “major”, and therefore justifying activation of the team, depending on the context. For example, a 5.5 magnitude earthquake in mainland France will be considered as being major, whereas an earthquake of the same magnitude along a subduction zone elsewhere on the planet will not. The existence of research projects involving French teams in the area of the earthquake and the fact that an intervention by French teams is requested by the country concerned are also important factors.

Outside crisis periods, the team continues to deliberate on the means to be implemented to facilitate and improve the efficiency of post-seismic interventions. In particular, joint action protocols are discussed at a European level.

The team has no mobile instruments of its own, but operates in close collaboration with the managers of the national seismological and geodetic mobile instruments, mainly those of CNRS-INSU. If necessary, they can identify the instruments available in the laboratories that could be loaned for the limited period of the intervention.

Recent interventions:

• Aquila earthquake (Italy, April 6 2009, Mw 6.2)
  

  Intervention with 32 seismological stations, in collaboration with INGV (Istituto Nazionale di Geofisica e Vulcanologia)
  French correspondent: Christophe Voisin (CNRS, laboratoire ISTERRE)
  Participating laboratories and organisations: ISTerre, GeoAzur, BRGM, CETE méditerranée

• Haiti earthquake (January 12 2010, Mw 7.1)
  

  Intervention with 3 land seismological stations and 21 ocean bottom seismometers, in collaboration with IPGP, GeoAzur, Univ. Antilles, IFREMER.
  French correspondents: Bernard Mercier de Lépinay et Yves Mazabraud
  Participating laboratories and organisations: GeoAzur, IPGP, Univ. Antilles, IFREMER

• Chile earthquake (February 27 2010, Mw 8.8)
  

  Intervention with 27 seismological stations and 30 GPS receivers, in collaboration with Chile as part of the LIA "Montessus de Ballore" (Laboratoire International France – Chili)
  French correspondents: Jean-Pierre Vilotte et Christophe Vigny
  Participating laboratories and organisations: IPGP, ENS, ISTerre, IRSN, IRD