'Snowball Earth' theory melted

BBC ^ | Wednesday, March 6, 2002

[SunkenCiv]

Geoscientists in Scotland say they have evidence to disprove the controversial "Snowball Earth" theory - the idea that the planet was completely encased in ice just over 600 million years ago.

We are claiming that in reality there was not a totally frozen snowball Earth and that even during the coldest conditions large regions remained ice-free -- Dr Dan Condon

The team, from the University of St Andrews, has published its findings in the scientific journal Geology, after studying rocks in the west of Scotland, Ireland, Namibia and California. Drs Dan Condon, Tony Prave and Doug Benn say they have found evidence of sedimentary material, which could only have been derived from floating ice on open oceanic waters... The controversial theory that for millions of years the Earth was entirely smothered in ice, up to one kilometre thick, has been kicked around for more than 50 years. It rests on the apparently anomalous evidence of past glaciation in places that should have been much too hot - very near the equator. Even during the most severe ice age, many scientists thought that the ice only reached as far down as Northern Europe and the middle of the USA.

[SunkenCiv]

Hmm, maybe — I missed that. C-13 is the decay result of (sez here) boron-13 and nitrogen-13; the abundance of C-13 relative to C-12 (both are stable, ie don’t decay) in a mineral sample could be used to date that sample, or date the period of exposure to weathering.

http://www.astrobio.net/exclusive/293/when-did-life-on-earth-begin-ask-a-rock

“Normally, carbon-13 (C-13, with atomic weight 13), is much rarer than C-12. However, biological processes concentrate C-12, so when organic debris falls to the ocean floor, the C-12 to C-13 ratio rises still further in the sedimentary rock that forms. That ratio is preserved even in rocks that formed billions of years ago.”

however, also see:

http://www.sciencedaily.com/releases/2008/09/080910104202.htm

[DManA]

How do you explain all the cracks in the Earth.

How do you explain that N and S America fits into Africa and Europe perfectly?

[SunkenCiv]

How do you explain all the cracks in the Earth.

The Earth has cracks in it. That's the explanation.

How do you explain that N and S America fits into Africa and Europe perfectly?

It isn't true, but for such a superficiality to have any bearing on anything, it would be necessary for the elevations to have NOT CHANGED over 284 million years. Plate tectonics is warmed-over continental drift, and both are pareidolia.

[Ernest_at_the_Beach]

Haven’t seen that before...

[TigersEye]

There’s also a “Slushball Earth” version.

No one wants to get hit with that theory! ;^)

[Marine_Uncle]

"Haven’t seen that before..."
I'm staying out of this one.

[SunkenCiv]

:’)

[SunkenCiv]

This graphic shows the tilting of the Earth that might occur if a dramatic imbalance in the planet's mass distribution ever developed in the Arctic. According to the theory of true polar wander, a heavy spot in the Arctic -- caused by a very large upwelling of magma, for instance -- would reorient the planet over 5 to 20 million years so that the heavy spot would lie at the equator, changing the orientation of the Earth in relation to its poles. New evidence uncovered by the team of Princeton geoscientist Adam Maloof shows that this sort of reorientation may have occurred in the planet's distant past. (Graphic: Maloof Laboratory)