Replying to LO26520 --
Dear Chris, Dear LO'ers,
Chris finished his mail with:
PS. Did I hear someone say panafricanism?
I smiled. But maybe to your surprise Chris, the expression *Panafrican* is
not so unfamiliar for me. It is an expression that at least exists 60
years or so.
For a long time geologists were surprised of the fact that all over the
African continent granite rocks occur of almost the same age: roughly 500
million years. From Egypt to Madagascar, from Nigeria to Namibia. Most of
these granite rocks are incorporated in older rocks or contain remnants of
older rocks. These ages are derived from radiometric dating. Definitely,
the African continent is much older, it forms one of the greatest
'cratons' on earth. A craton is a solid nucleus of very old continetal
rocks with usually along its rims younger rocks and younger mountain
ranges. It seems that the African continent was rejuvenated some 500
million years ago. (That sounds fantastic, isn't it, Chris?).
[Since Africa and South America were once one large continent, the same
500 My ages are found there. In Brazil these event of rejuvenation is
called Braziliano]
The explanation of this geological event is still not clear. Personally I
have a weird explanation for it, but is too much out of scope now.
I hope that a new Panafrican event will come, rejuvenating and refreshing
the present Mental Models of much of its inhabitants. I hope Africa will
then be the delightful example and mirror for the rest of the world.
dr. Leo D. Minnigh
l.d.minnigh@library.tudelft.nl
Library Technical University Delft
PO BOX 98, 2600 MG Delft, The Netherlands
Tel.: 31 15 2782226
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Let your thoughts meander towards a sea of ideas.
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--Leo Minnigh <l.d.minnigh@library.tudelft.nl>
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