Hi Jochen and others
I agree with the others about the interpretation of the zircon CL pattern that you posted to the list. However, it might be worth considering crystal-plastic deformation and associated localized trace element diffusion as another potential cause of disruption to primary CL patterns in zircon.
Timms, N.E., and Reddy, S.M., 2009, Response of cathodoluminescence to crystal-plastic deformation in zircon, Chemical Geology, 261, (1-2), 11-23.
Regards,
Nick
_______________________________________
Dr Nick Timms
The Institute for Geoscience Research (TIGeR)
Department of Applied Geology
Curtin University of Technology
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_______________________________________
-----Original Message-----
From: Metamorphic Studies Group [mailto:[log in to unmask]] On Behalf Of Jochen Mezger
Sent: Monday, 17 May 2010 11:13 PM
To: [log in to unmask]
Subject: Zircon CL-pattern -thanks
Thanks to all,
for providing valuable information and hints. I
have ordered a copy of the RIM zircon volume, and
got a hold of the Zircon issue of "Elements" (the
website of Elements apparently does not work at
the moment). I will also look at some of the recommended authors.
I may also have the chance to get BSE images from
these zircons. Considering the causes for such
patchy or mottled textures, Simon called it
"brain texture" [I like that one; or maybe "BSE
brain texture" :) ], I should consider myself
lucky for the fact that one third of the analyses
of that sample provide meaningful concordant ages.
Best wishes and merci bien,
Jochen
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Dr. Jochen Mezger
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Allgemeine Geologie
Martin-Luther-Universität Halle-Wittenberg Tel.: 49-0-345-5526120
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