Hi
Doug,
> Don't dried lakebeds have elevated salts due
to the evaporated waters & run-off
>
they have received over the years - the Salton Sea comes to mind for
example,
>
not to mention may others like it around the world-, and if so, how does
this
>
manifest itself on meteorites being found, say in California dried (pre)
historical
>
lakes?
The short answer
is that meteorites don't like it! (The Salton Sea is
probably
not the best
example since it isn't natural and thus isn't very
old, but I get
what
your asking). Dissolved salts are obviously not good for
meteorites -- a
meteorite that
periodically sits in saltwater has got to be worse
off than
one that spends an
equal amount of time in fresh water. My experience
has
been that
meteorites found on dry lakes can look quite fresh on the
outside,
but be
weathered to W5 or beyond on the inside. 100% fusion crust
can
protect a
meteorite's innards, but all it takes is one crack in the
surface
to begin the
downward spiral. Water's unusual phase diagram (water
denser
than
ice) only serves to accelerate the process, with freeze and thaw
cycles
fracturing meteorites
into smaller and smaller fragments as the
centuries
pass.
--Rob
