Re: Shrinking Earth

>If the North American Plate has been moving against the Pacific Plate at 2
>Cm/Yr for 100 million years (just a slice of time for analysis), where did
>all of those 200,000,000 cm of crust go?

People think it eventually melts and mixes back into the mantle. It
can be tracked
down the first 700 of theose 2000 km by plotting earthquakes in that
crust.
Deeper than that its suspected to be too soft. Some seiismic
tomography
people claim to see velocity anomalies all the way through the mantle,
while others debate this.

Some of the melt rises to the surface quickly at the subduction zone
volcanoes.

.

Relevant Pages

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  • Re: Tidal forces on the magma, and earthquakes.
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  • Re: Owens Two-Phase Model of Earth Expansion
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  • Re: Gas reserves deep in the Earth? - New research
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  • Re: PLATE MAPS OF THE PAST
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