Iron Crystal Core? [was "earth/moon relationship"]

Geoff Smith (geoffs@unixg.ubc.ca)
Wed, 29 Oct 1997 11:06:56 -0800 (PST)


On 29 Oct 1997, Anders Sandberg wrote:

> EvMick@aol.com writes:
>
> > And I heard (somewhere,can't remember, no references..but recently....sorry)
> > that some evidence had been "unearthed" that the core of the earth was a
> > single (huge) iron crystal...
> >
> > In accordance with principles set forth in "Demon Haunted World"....is this
> > bogus? or actually possible.
>
> I'm not sure, and I'm not a geologist, astrophysicist or even a
> physicist, but I would argue it is unlikely. The core is believed to
> contain not just nickel-iron, but other heavy elements. This suggests
> to me that the core cannot form a nice crystal lattice, and likely has
> an amorphous structure. But a lot likely depends on the behavior of
> this mixture at high pressures and temperatures; things can get rather
> counterintuitive down there, so I wouldn't be totally surprised if it
> occured.
>
> Is there a geologist in the house? :-)

I seem to remember reading an article that stated that the very centre of
the core was a massive crystal(I think of iron) How was this determined?
Well, don't quote me on this, but I think either someone shot some time of
EM radiation through the earth and measured it's distortion on the other
side (of course, the radiation would be altered differently depending on
how it entered the grain of the crystal) Hmm... that doesn't sound like a
very likely scenario now that I think about it. How about this: when an
earthquake occurs on the other side of the planet, you measure how long it
takes to go through the diameter of the earth. The time it takes should
be influenced by the direction the shock wave passes through the crystal.
Apparently, the arrangement of the domains of this large iron crystal
explain the earth's large magnet field. Also, one could explain pole
shift(not the kind Danny was talking about!) by the inversion of this iron
crystal, which might be induced by some external magnetic field... a large
metallic asteroid? Sorry I'm being so vague... has anyone else read the
article to which I am poorly alluding?

Geoff.