講演情報
[PPS02-P04]Topographic-albedo-magnetic field correlations found at the Descartes magnetic anomaly
*Hyeonhu Park1、Ian Garrick-Bethell2、Ho Jin1 (1.Kyung Hee Univ.、2. UC Santa Cruz)
キーワード：
Moon、Magnetic anomalies、Lunar swirl、Descartes、Magnetization
The Moon’s crust exhibits localized regions of strong magnetic anomalies, the origin of which are mostly unknown. Some strong lunar crustal magnetic anomalies are in antipodal deposits of ejecta from large impact basins. The Descartes magnetic anomaly, which is one of the strongest isolated anomalies with high albedo, is located near the antipode of the pre-Nectarian Dirichlet-Jackson (DJ) basin, but also near the rim of the Nectaris basin. It is also oriented radial to the Imbrium basin. Here we investigate the hypothesis that the magnetized material near Descartes is comprised of DJ basin ejecta using geologic relationships. We found that the high albedo materials of the Descartes anomaly (centered at 10.6° S, 15.9° E) is part of a quasi-circular cluster of magnetism that is located within ~6 degrees of the DJ basin (centered at 13.4° N, 158.2° W) antipode. This compares with ~3 degrees for the more well-known Gerasimovich family of anomalies at the antipode of the Crisium basin. We find topographic-albedo-magnetic field correlations that are especially pronounced just north of Descartes crater, and some high albedo deposits appear to spill into this crater. These findings appear to be the first topographic-albedo-field correlations found at a lunar swirl and magnetic body. The topography can be used to estimate the ejecta thickness and demonstrate that the magnetization is surficial. Also, this would help estimate the magnetic source volume. In turn, this can help estimate the rock magnetization strength and constrain the magnetizing field value, assuming different rock types.