Characterization of regional and local scattering effects from small-aperture seismic array recordings

Journal of Seismology, v. 9, n. 2, p. 137-149, 2005. http://dx.doi.org/10.1007/s10950-005-8234-1International audienc

Apport des antennes sismologiques pour l'analyse de l'influence régionale des hétérogénéités géologiques sur la propagation des ondes - Les expériences de Caille 1994, Annot 1998 et du LSBB 2001

Cahier technique AFPS-CFGI "Géologie et risque sismique", 49-5

Une expérience multi-antennes à Annot pour l'analyse des effets de site en sismologie: A multi-array experiment in Annot for site effect analysis

Durant deux mois, les vibrations du sol induites par la sismicité naturelle ont été enregistrées par 4 réseaux denses, comprenant chacun 9 stations sismologiques. La zone choisie couvre une superficie de 400 km2 et présente une topographie avec des orientations bien marquées. Les sites correspondent à des fonds de vallées plans et remplis de sédiments récents peu consolidés. Les données acquises lors de cette expérience serviront à caractériser les trains d'ondes traversant ces différentes vallées (azimuts des contributions énergétiques principales, vitesses apparentes) dans le but de quantifier les effets de site

Energetic charged particles above thunderclouds

The French government has committed to launch the satellite TARANIS to study transient coupling processes between the Earth’s atmosphere and near-Earth space. The prime objective of TARANIS is to detect energetic charged particles and hard radiation emanating from thunderclouds. The British Nobel prize winner C.T.R. Wilson predicted lightning discharges from the top of thunderclouds into space almost a century ago. However, new experiments have only recently confirmed energetic discharge processes which transfer energy from the top of thunderclouds into the upper atmosphere and near-Earth space; they are now denoted as transient luminous events, terrestrial gamma-ray flashes and relativistic electron beams. This meeting report builds on the current state of scientific knowledge on the physics of plasmas in the laboratory and naturally occurring plasmas in the Earth’s atmosphere to propose areas of future research. The report specifically reflects presentations delivered by the members of a novel Franco-British collaboration during a meeting at the French Embassy in London held in November 2011. The scientific subjects of the report tackle ionization processes leading to electrical discharge processes, observations of transient luminous events, electromagnetic emissions, energetic charged particles and their impact on the Earth’s atmosphere. The importance of future research in this area for science and society, and towards spacecraft protection, is emphasized