Open AccessPaleomagnetic poles of Mars: Revisited
Author(s) -
ArkaniHamed Jafar,
Boutin Daniel
Publication year - 2004
Publication title -
journal of geophysical research: planets
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2003je002229
Subject(s) - paleomagnetism , geology , geophysics , geomagnetic pole , geodesy , earth's magnetic field , magnetic anomaly , mars exploration program , physics , cluster (spacecraft) , dipole , altitude (triangle) , magnetic field , geometry , astronomy , mathematics , quantum mechanics , computer science , programming language
The huge amount of data acquired by Mars Global Surveyor during its mapping period provides a unique opportunity to reassess the paleomagnetic pole positions of Mars previously determined on the basis of the limited low‐altitude magnetic data. We identify nine small and isolated magnetic anomalies on the basis of the global magnetic maps and model each anomaly using a vertical prism of elliptical cross section. Both high‐altitude (360–430 km) and low‐altitude (100–200 km) magnetic data are used simultaneously. We calculate a paleomagnetic pole position assuming that the body is magnetized by a dipole core field. Although the new pole positions do not cluster as closely as the old ones, the new cluster overlaps the older cluster. The clustering suggests that Mars' rotation axis has likely wandered by ∼50°–60° in the last ∼4 Gyr. The number of north and south poles in the cluster suggests at least one reversal of the core field during the time the source bodies acquired magnetization.