On Sat, Jan 26, 2019 at 08:57:01AM -0800, shadow at shadowgard.com (via tml list) wrote:
> Take some time to heat the rock a mile or two down hotter than it
> already is. Remember, there are organisms that live in mineral
> springs that run 100 C or more.

Yes, it would take some time.  The temperatures down there are a
result of the small but steady heat flow from the inner earth to the
cooler surface.  If you keep the surface hot, everything deeper in the
crust heats up by almost the same amount.

> Don't forget that the base of those ecosystems is single-celled
> organisms that live in fluid coming out of the black smokers. Which
> is can be as hot as 464 C!!!

While some organisms can survive very high temperatures for a time,
no known life form can reproduce at more than 130 C.

- Tim