On Thu, 21 Aug 2003 12:30:11 -0700 (PDT) 
Robert Verish

>This most recent influx of moisture 
>into the deserts has caused severe 
>flash-flooding.  Up until now, the
>"dry" lakes have been overly wet with 
>standing water, but flash-flooding 
>has the energy to bring large volumes 
>of mud and rock with that water, out 
>into the middle of these playas and 
>bury any promising surface with a new 
>layer of sediment. 

First, the flooding is not going carry
any rock of any size into the playa. 
Any rock, except for pumice, of any 
size is going to drop out along the 
edges of the playa lake. Just the finer-
grained sediments, i.e. mostly silt and
clay will get carried out into the playa.
Along the edges of any playa, there 
might be a substantial accumulation of
sediments. However, the actual thickness
of accumulation will drastically decrease
towards the interior of any lake bed to 
the point where it can be quite thin.

Finally, the deposition of sediment is
not altogether a bad thing. Any of the 
clutter and garbage that has accumulated 
on the playa lake surfaces because of 
human activity should be buried, in a 
some cases just awhile, giving the 
meteorite hunter a clean surface on 
which a person can more easily find 
any meteorite falls after the lake 
dries out.

I qualify my statements with "awhile" 
because, in some lake beds, the 
pedoturbation of the lake sediments 
after the lake bed dries out might 
cause larger pieces of rock, older
meteorites, and human debris to 
resurface in the next decade or so 
if they are not too deeply buried.
Also, after a lake dries out, wind
action can significantly erode and
move any silt, clay,or fine sand that
might accumulated during these floods
and also expose, in time, objects
buried outside of the lake margins. 
Again, in time, some of stuff that 
was buried by these floods within the 
lake beds away from its margins will 
start to resurface in the next few 
years as wind erodes the new lake 
sediments and deflates the lake surface.


Baton Rouge, LA

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