Crucial detail of the wall, used as proof for the anatectic model for the Evje-Iveland pegmatites

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Crucial detail of the wall, used as proof for the anatectic model for the Evje-Iveland pegmatites

This image is copyrighted. Unauthorized reproduction prohibited.

This detail of the Iveland Wall is interpretated by Müller (2017a) as part of the proof for the anatectic model for the pegmatites of the Evje-Iveland pegmatite field.

Further study by students of the University in Bonn will either confirm or challenge this theory.

Interesting to note is that an overall view of the wall rather suggests that what can be seen here, is a breccia being glued together by pegmatitic melts.

Certain details in the wall seem to contradict the anatectic model for exactly this exposure, though the complexity of the criss-crossing veins makes it very hard to reconstruct a proper chronology of events.

The melts itself can very well be derived from the melting of the host rock, though not necessarily from the rocks exposed in the wall.

Any contributions to this discussion are welcome!

This Photo was Mindat.org Photo of the Day - 12th Oct 2019

This photo has been shown 389 times
Photo added:30th Aug 2019
Dimensions:5312x2988px (15.87 megapixels)
Date/Time of Photo:27th Aug 2019 11:42:13
Exposure time:1/149s
Focal Length:5mm
Focal Length (35mm film equivalent):31mm
ISO speed:40
View The Evje og Hornnes geomuseum, Fennefoss' Photos

Discuss this Photo

Photosgranites and the nature of proof

12th Oct 2019 01:52 BSTTony Peterson Expert

EDIT: Photo link added

I'd avoid saying any observation in geology can be offered as "proof"......the cumbersome, but to me best phrase is, "is consistent with..........." or "does not contradict.....". Proofs were things I saw in linear algebra.

This slab, and the outcrop it came from, may "be consistent with" both models you suggest! There is no reason why granites, surely the messiest systems an igneous petrologist gets to deal with, cannot be sourced both from a deeper locale and the inclusions they partially melt and digest along the way.  At least, you're not proposing in situ granitization

12th Oct 2019 02:04 BSTPaul Brandes Manager

What slab, and what is this in reference to? :/

12th Oct 2019 05:05 BSTFrank K. Mazdab Manager

the comment appears to refer to the POTD, 12 October 2019.

12th Oct 2019 12:15 BSTRalph Bottrill Manager

Tony has a point about proof in geology often being very subjective, though the title of the picture reads “...used as proof...”, which suggests  it’s open to question to the uploader.

12th Oct 2019 18:44 BSTGareth Evans


Proof in Geology! It is all too confusing for me, probably the reason I majored in Chemistry and Physics. :)


12th Oct 2019 18:55 BSTJolyon Ralph Founder


12th Oct 2019 14:26 BSTPaul Brandes Manager

Ok, I see now. But, it would have been nice to start this discussion from the photo itself rather than a stand alone thread.

12th Oct 2019 17:10 BSTUwe Kolitsch Manager

Photo link added to original message.

12th Oct 2019 19:07 BSTPaul Brandes Manager

Thanks Uwe.
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