Monday, 18 August 2008

Quote of the day

Read & Weep. Found this one on the blog of Jennifer Marohasy. It might have been funny if it weren't this nonsense is posted by someone with a PhD in science. As a geologist i want to cry. It's a fine example of how a firm semi-religious belief in something (in this case : a political viewpoint) makes people making the most ridiculous errors and using incredible fallacies to make science fit into the dogma. Even if this requires a form of reasoning that is simply ridiculous.

Gordon Robertson on a Molten Core

I have become curious about something. The core of the Earth is alleged to be molten. It's also a fact that the deeper you dig into the Earth, the warmer it gets. Where is that heat coming from... surely not from the Sun. What's the possibility that the Earth generates some of it's own heat from geothermal processes?

When I studied a bit of geology, we learned that the Earth is actually oblate, like a pumpkin. That shape apparently comes from the stress of the gravitational pull of the Sun the Moon. As the Earth moves in its orbit about the Sun, it is flexing due to those stresses, and cracks in the Earth heat up as they rub against one another.

There are estimates that the Earth's core may be in the vicinity of 5,000 to 6,000°C. That heat has to go somewhere. There is also a theory that the core may be turning at a differnt rate than the rest. There would be immense friction in that case, and immense heat generated.


3 comments:

  1. Oh dear. The cat has it right. Just in case anybody doesn't know these things (which they could have encountered any time from middle school onward):

    The earth is an oblate spheroid because it rotates and is not infinitely strong mechanically. The tidal forces from the moon and sun can only account for 10-20 cm of deformation, not the 20+ km we observe.

    We know there's a liquid outer core because seismic waves of a sort that require a solid to propagate through don't pass through this zone.

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  2. LOLcat!

    Marohasy is the worst. A biologist, entomologist I think, who shills for the IPA who receive funds (in shillings, I guess) from Exxon Mobil Australia.

    Her intellectual dishonesty in supporting the 'earth cooling since 1998' meme is abhorrent!

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  3. Thanks Robert for adding some explanations. I thought it was so obvious i didn't need to post them, but in retrospect you're right to give them anyway.

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