HR: 0800h
AN: P51C-0669    [Abstracts]
TI: Paleomagnetic Pole Locations of Lunar Swirl Albedo Magnetic Anomalies: A possible Pre- existence of Ancient Lunar dynamo
AU: * Sherif, B M
EM: berguig@ipgp.jussieu.fr
AF: Institud de Physique du Globe de Paris, 4 avenue de Neptume St-Maur les Fossés, Paris, 94100, France
AU: Mohamed, H
EM: hamoudi@ipgp.jussieu.fr
AF: Institud de Physique du Globe de Paris, 4 avenue de Neptume St-Maur les Fossés, Paris, 94100, France
AU: Yves, C
EM: cohen@ipgp.jussieu.fr
AF: Institud de Physique du Globe de Paris, 4 avenue de Neptume St-Maur les Fossés, Paris, 94100, France
AB: The nature and the origin of the magnetic fields responsible of lunar remanent magnetization are highly debated. There are two possible magnetization processes; either the crustal field was generated by an ancient lunar dynamo or it was generated by external transient fields impact. Here, we investigate the hypothesis that the lunar magnetic field was generated by a paleo lunar dynamo process. Magnetometer data obtained by Lunar Prospector showed high swirl albedo over certain regions were inverted to determine paleomagnetic pole locations. These selected formations seem to have an Imbrian age. The mostly lie antipodal to large impact basins such as Descartes Formation, Mare Marginis, Mare Ingenii and Gerasimovich. The Reiner Gamma and Airy crater have not previously associated with antipodal impact basins. The modeling of these anomalies shows a clustered paleomagnetic pole positions within a radius of 35 degrees centered at (30S, 225E). This result supports the hypothesis of a now extincted paleo lunar dynamo that may have probably magnetized rocks of lunar crust. The scattered positions of the other obtained paleomagnetic pole locations suggest that the lunar remanent magnetization were since modified by subsequent impact events.
DE: 1595 Planetary magnetism: all frequencies and wavelengths
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting