RE: RATE Vol. II

If all five continents formed a single unit on the surface of the earth, does that mean there were no oceans?

 
Moorad

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From: asa-owner@lists.calvin.edu on behalf of Randy Isaac
Sent: Fri 5/19/2006 8:47 AM
To: asa@calvin.edu
Subject: Re: RATE Vol. II

I'm not sure I follow. Why is plate tectonics necessary for a planet to
sustain life? It was probably necessary to produce the particular earthly
configuration we see today but why would it be true in the more general case
that plate tectonics is necessary to sustain life?

Randy
----- Original Message -----
From: "Bill Hamilton" <williamehamiltonjr@yahoo.com>
To: "Randy Isaac" <randyisaac@adelphia.net>; <asa@calvin.edu>
Sent: Thursday, May 18, 2006 10:33 PM
Subject: Re: RATE Vol. II

> In fact radioactive decay helps produce the heat necessary to keep the
> magma
> liquid, which in turn supports plate techtonics, which many
> astrobiologists
> consider necessary for a planet to sustain life.
>
> Bill Hamilton
Received on Fri May 19 17:10:40 2006