Dear all, March 1, 1999
In the course of doing a fair amount of thin section petrography on
metapelitic rocks, I have looked at a number of graphite-rich and
graphite-poor samples collected from essentially the same outcrop (biotite
into sillimanite zones). I have noticed that the presence of abundant modal
graphite (say, greater than 1+ %, so that it noticably starts to affect the
groundmass color) in a metapelite seems to have an obvious, pronounced
effect on the nature of the textures seen in one rock versus the other. I
expect that others have made this same observation because I rather doubt
that I've been looking at any rocks that are in some way unique or special.
I'm curious to hear, have other petrographers have made a similar
observation? If so, does anyone have any suggestions why such an effect
occurs? Also, does anyone know if this has been discussed specifically
anywhere in the literature?
Many thanks for any input that can be provided on my questions.
Cheers,
Chuck Guidotti
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C.V. GUIDOTTI Univ. Phone (207) 581 2153
UNIVERSITY OF MAINE Univ. Fax (207) 581 2202
DEPARTMENT OF GEOLOGICAL SCIENCES Home Phone (207) 947 1388
5790 EDWARD T. BRYAND GLOBAL SCIENCES BLDG. Home Office Phone (207) 947 6086
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U.S.A. Dept.Home Page
http://www.geology.um.maine.edu.
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