HR: 14:10h
AN: T43E-03 [Abstracts]
TI: Seismo-Electromagnetic Effects Observed by DEMETER in the Ionosphere
AU: * PARROT, M
EM: mparrot@cnrs-orleans.fr
AF: LPCE/CNRS, 3A Avenue de la Recherche, ORLEANS, 45071
France
AB:
The French micro-satellite DEMETER was launched on June 29, 2004 on a polar and circular orbit with an altitude of 700 km.
One of its main scientific objectives is to detect in the ionosphere, anomalous variations of electromagnetic waves, particle
fluxes or thermal plasma parameters which could be related to seismic activity. If it is shown that such perturbations are
real and systematic, they could be considered as short-term precursors, occurring between a few hours and a few days before
the quake. There are several hypotheses to explain the generation mechanism of these phenomena (wave emissions from the
Earth's crust, piezo- or tribo-electric effects, emissions of radioactive gas or metallic ions, propagation
of acoustic-gravity waves, .). The payload of the micro-satellite allows to measure waves in a broad frequency
range and also important plasma parameters (ion composition, electron density and temperature, energetic particles). The
scientific payload is composed of several sensors: - Three electric and three magnetic sensors (6 components of the
electromagnetic field to investigate from DC up to 3.5 MHz), - A Langmuir probe, - An ion spectrometer, and, - An energetic
particle analyzer. There are two modes of operation: (i) a survey mode to record low bit rate data all around the Earth, and
(ii) a burst mode to record high bit rate data above seismic regions. The telemetry is received in Toulouse and sent to the
DEMETER mission center in Orléans where data and plots are processed (http://demeter.cnrs-orleans.fr). After eighteen
months of operation, the paper will present significant events recorded when the satellite is close in time and in space to
earthquakes. The main purpose of the project is to perform a statistical analysis with many events in order to determine the
main characteristics of the seismo-electromagnetic effects and methods which are currently operative will be explained.
DE: 2435 Ionospheric disturbances
DE: 2487 Wave propagation (0689, 3285, 4275, 4455, 6934)
DE: 6984 Waves in plasma (7867)
DE: 7223 Earthquake interaction, forecasting, and prediction (1217, 1242)
SC: Tectonophysics [T]
MN: Fall Meeting 2005