Glassy pseudotachylites often do not survive more than about 25 M yr without devitrification. Are you looking at fine-grained devitrification products?
Ernie Rutter
-----Original Message-----
From: Tectonics & structural geology discussion list [mailto:[log in to unmask]] On Behalf Of Urai, Janos
Sent: 10 October 2014 08:06
To: [log in to unmask]
Subject: Re: Problem related to Pseudotachylite
Arindam,
perhaps your samples are cataclasites or ultracataclasites, and not true pseudotachylites.
Janos Urai
On 10 Oct 2014, at 08:30, arindam sarkar <[log in to unmask]> wrote:
Respected Teachers and Dear Friends,
I am working on "Pseudotachylites" of India. I have collected lots of samples of it, appearing as dark in hand specimen. But after the preparation of the thin section, these samples are showing light color under microscope and with out microscope which are completely uncorrelatable with the hand specimen. Actually, I did not get any possible reasons of this problem.
If you (group members) kindly intimate me the possible reasons or suggest me solution of this problem, I will be highly obliged.
Thank you,
Regards,
--
Arindam Sarkar
Doctoral Fellow (Ph.D.)
Centre for Advanced Studies in Geology,
University of Delhi, Delhi-7
Mob: +91 9717118391
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