Hotspots leave magnetic scars on Mars

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Source:  Eric Hand, Nature

Excerpt: …Mars Global Surveyor (MGS) …magnetometer.... A section of the martian crust appeared to consist of long 'stripes' of iron-bearing minerals permanently magnetized with alternating orientations. …Ken Sprenke of the University of Idaho…has provided a tantalizing theory to explain these stripes: they were created by ancient hotspots beneath the crust. The hotspots would exhume material from the interior that would then 'freeze' with the magnetic field holding sway at the time. …Sprenke points out how the stripes recall a famous, elongated feature made by a hotspot on Earth: the Hawaiian islands.
 
www.nature.com/news/2010/100625/full/news.2010.312.html

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