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Topics - Joeval

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Flat Earth Q&A / Volcanics on a FE?
« on: February 10, 2011, 03:06:51 AM »
(Partly because LyingTruth is being a jackass about the topic...)

How would the various types of volcanoes and volcanic settings work on a FE?

We have several different types in RET, I'm not sure how they would work on a FE, what with no discernible core/mantle, and outright rejection of plate tectonics in certain circles.  As I recall, the FAQ/Wiki doesn't answer these terribly well, either.

Mid Ocean Ridge volcanism.
This is caused by depressurisation of the upper mantle as the oceanic crust is pulled apart.  The lower pressure initiates a partial melt of the upper mantle, and forms a roughly Basaltic melt.  This can be seen all over the place beneath the sea, and on land as a Mid Ocean Ridge cuts through Iceland.

Island Arc volcanism.
Found around Subduction zones, these form when a plate is subducted.  As the plate is subducted, it gives off volatiles (mostly Water, and bits and pieces from the sediment that had accumulated on top of the plate). These volatiles lower the melting point of the overlying mantle wedge, and produces a Basaltic melt, that rises through the overriding plate and becomes more acidic through fractional crystallisation and assimilation of continental crust.  When this reaches the surface, it tends to be an Andesitic or Rhyolitic lava.  Or, it can find itself unable to rise, if it becomes too acidic, and you'll get a granitic pluton.

Hot-Spot Volcanism.
As found in Hawaii, and (if you look on topographic/bathymetric maps, the Emperor Seamount Chain) a rising plume of heat from the mantle, bringing with it deep mantle material, intersects with the crust and a volcano erupts.  A basaltic melt is produced, with markedly different geochemistry to the basalt of Mid Ocean Ridge basalt.

Thanks guys


(tl;dr - different types of Volcano and volcanic setting aren't described in the FAQ or Wiki, and I can't see how they'd work on a FE.)

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The Lounge / To any Linux users... What is the best distro?
« on: July 11, 2009, 02:48:07 AM »
Woo, first thread in Everything Else!

Anywho, I've seen a few Linux users around here, and I use Linux at the moment as well.

So, what is the best/your favorite distro?  By all means say why as well.

Currently, I'm using Mint 7, and quite like it.

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