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Re: Antarctica...how cold?
From: William Gibson Parker <firstname.lastname@example.org>
To: Larry Febo <email@example.com>
Cc: firstname.lastname@example.org <email@example.com>
Date: Saturday, December 11, 1999 3:15 PM
Subject: Re: Antarctica...how cold?
>Lystrosaurus is known from early, early middle Triassic rocks in
>Antarctica. The early Permian rocks in the Transantartic Mountains contain
>many sediments suggesting the presence of glaciation, including
>diamictites...etc.. then suddenly in the middle to late Permian there is a
>vast change to coal measures and sediments full of Glossopteris and
>Gigantoperis. Volcaniclastic are also prevailient in the Late Permian
>sections due perhaps to a large island arc system of of the East Antarctic
> Although there are no Late Triassic vertebrates known from the
>Late Triassic of Antarctica that I am aware of, the environment was right
>for them. Transition of the Transantarctic Basin to a foreland setting,
>rapid subsidence and sediment accumulation in a braided stream system was
>Coal measures and numerous Palynomorphs show the area still possessed a
>seasonally warm climate.
> There are Jurassic dinosaurs known from Antarctica, the large
>theropod Crylophosaurus (sic?), also I believe two smaller unknown
>theropods were found, (I'm writing this without notes in front of me, I
>can give references later.) As for the Cretaceous there is an Ankylosaur
>known from the Antarctic Peninsula.
> So, the climate and setting was right for dinosaurs, there is a,
>albeit small, Triassic, Jurassic, and Cretaceous record, so were there
>Pterosaurs on Antarctica? Most likely, except that we are looking at the
>incompleteness of the fossil record, especially in Antarctica where there
>is less than 2% outcrop exposure.
>By the way the current Antarctic Ice Sheet did not form until the
>Oligocene so there should be an early Tertiary record as well. Bring on
>the Greenhouse effect! Let's melt that cap!
>Hope this helps
Thanks for all that info Bill, (and thanks to Jerry Harris too!). I guess
climate could change many times over in the span of a hundred million years
(give or take a few). I do suppose though, because of it`s higher latitude,
it was generally much cooler than
the equatorial belt at any given time,...even back then.