Geophysics Hot fluids or rock in eclogite metamorphism? (Reply)

Bjørnerud and Austrheim interpret the geological evidence in the rocks of Holsnøy at Lindås nappe, Norway, to be inconsistent with our cold-crust model, but do not question our new argon isotopic data, on which we base the thermal history of the terrain. A critical flaw underlying their arguments is...

Full description

Saved in:
Bibliographic Details
Published in:Nature 2006-03, Vol.440 (7082), p.E4-E5
Main Authors: W, James K, Camacho, Alfredo, Hensen, Bastiaan-J, Braun, Jean
Format: Article
Language:English
Subjects:
Argon
Diffusion
Geology
Geophysics
Isotopes
Metamorphism
Rocks
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Bjørnerud and Austrheim interpret the geological evidence in the rocks of Holsnøy at Lindås nappe, Norway, to be inconsistent with our cold-crust model, but do not question our new argon isotopic data, on which we base the thermal history of the terrain. A critical flaw underlying their arguments is the implicit assumption that element diffusion does not occur in dry environments, although there is clear evidence to the contrary. Counter to earlier claims of element and isotope immobility in dry rocks, we have demonstrated the existence of diffusion profiles in phlogopite associated with the uptake of argon during the Caledonian in 'unreacted' protolith of the Lindås nappe. Diffusion has taken place in these dry rocks and cannot be ignored.
ISSN:0028-0836
1476-4687
DOI:10.1038/nature04715