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Posted on 02/22/2016 9:23:26 PM PST by BenLurkin
Antarctica is known by meteorite specialists as a fruitful hunting ground, because the rocks are collected from their landing sites by glacial flows and transported to concentrated dumping-grounds.
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Among this Antarctic haul, however, researchers have noticed that iron-rich meteorites - whether partly or wholly made of the metal - are surprisingly scarce, compared to the percentage collected in other places around the world.
Dr Joy and her colleagues think they may have discovered why.
They froze two small meteorites of similar size and shape, one made of iron and the other rocky and non-metallic, inside blocks of ice. A special lamp was trained on the ice from above, to mimic the rays of the Sun.
Both meteorites, on repeated trials, melted their way downward through the ice block. But because the metal conducts heat more efficiently, the iron meteorite sank further, faster.
The researchers then expanded that observation using a mathematical simulation. Their model showed that this Sun-driven burrowing would be enough to cause iron-rich rocks to sink so much during the long summer days that, over the course of the year, it would account fairly precisely for the lack of iron space rocks welling their way to the surface of the Antarctic "stranding zones".
"The idea is, they never make it to the surface. They're forever trapped, 50-100cm or so below the ice," Dr Joy explained.
That means, if the team's findings are to be believed, that the hunt is on
(Excerpt) Read more at bbc.com ...
Your dog must be on a high iron diet...
What with humans causing the ice to melt these things will quickly surface.
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