Re: OT-CHAT: calcium in water

In addition to uplift and subsidence, there were also cycles of rise and
fall of ocean levels with global warming and cooling cycles.

I had never really thought about it before - the glaciers reworked
surface geology so much in the northern US, that I had never realized
that there could still be intact limestone bedrock underlying glacial
deposits.  And I didn't realize there was open water all the way up the
middle of the continent.

<.... the Arctic Ocean connected to the Gulf of Mexico several times
with the rise and fall of the continent>

My understanding was that a few valleys, including Sequatchee Valley
here in east Tennessee and Cades Cove in the Smokies resulted in part
from 'tears' in layers being pushed up over basement rock, sort of like
pizza dough if you try to spread it too fast & far.

<..the crest of Crab Orchard (?) ridge which further south becomes the
valley of the
Sequatchee River..>

I'm not sure about depth, but from what I've read, limestone formed in
shallow salt water open seas with little wave action and no sediment.
Plus I think they come from a much older time period than coal bearing
shales?  Precambrian vs carboniferous? (I had to go look it up -
<http://gpc.edu/~pgore/geology/geo102/timechrt.htm>

<Limestone formed further west from south to north in deeper water of
amenable temperatures, although the water extended from the Gulf to the
pole.>
--
Linda Mann east Tennessee USA zone 7/8
East Tennessee Iris Society <http://www.korrnet.org/etis>
American Iris Society web site <http://www.irises.org>
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