Magnetization, Paleomagnetic Poles, and Polar Wander on Mars

Pole wandering of Mars: Evidence from paleomagnetic poles

“…Many investigators considered the problem of estimating the paleomagnetic pole position of Mars (e.g., Sprenke and Baker, 2000;Arkani-Hamed, 2001;Hood and Zacharian, 2001;Richmond and Hood, 2003;Arkani-Hamed and Boutin, 2004;Sprenke, 2005;Frawley and Taylor, 2004). The paleomagnetic pole position not only provides a means to determine the magnetization of the crust through inversion of the magnetic anomalies (Arkani-Hamed, 2002), but also has indirect inferences about the rotational dynamics of the planet.…”

Planetary Magnetism

“…There is great interest in identifying a Mars paleopole, and a number of authors have sought to determine ancient pole position(s) on Mars by fitting various magnetized sources to MGS magnetic field observations (Arkani-Hamed, 2001b; Arkani-Hamed and Boutin, 2004;Boutin and Arkani-Hamed, 2006;Frawley and Taylor, 2004;Hood et al, 2010;Langlais and Purucker, 2007;Sprenke and Baker, 2000). A large number of putative paleopoles have been proposed but as yet no consensus has emerged (for a recent compilation, see Milbury et al, 2012).…”

“…Connerney et al (1999) found the magnetic lineations on Mars sufficiently reminiscent of the pattern of magnetization associated with seafloor spreading on Earth that they proposed a similar mechanism -crustal spreading in the presence of a reversing dynamo -for the evolution of the Mars crust. Sprenke and Baker (2000) modeled crustal magnetization in the southern highlands using the same aerobraking observations and inverse methods used by Connerney et al (1999). Their models imposed constraints on the direction of magnetization ('normal' and 'reversed') and allowed for a variation in the intensity of magnetization in the cross track direction.…”

An Origin for the Linear Magnetic Anomalies on Mars through Accretion of Terranes: Implications for Dynamo Timing

“…These anomalies have alternating strong and weak magnetic signatures, a pattern which is comparable to much weaker linear magnetic anomalies observed in the Earth's oceanic floor. Thus, this pattern on Mars was proposed to be genetically related to seafloor spreading in the presence of a reversing dipolar magnetic field (Connerney et al 1999, Nimmo 2000, Sprenke and Baker 2000. Sleep (1994) had already proposed that plate tectonics operated on Mars in the Noachian, although he considered the lowlands instead of the highlands as the ancient oceanic crust.…”

“…Even the existence of anomalies may be due to impact demagnetization of a previously globally magnetized crust (Sprenke and Baker 2000, Arkani-Hamed 2001, Hood et al 2002.…”