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The tectonic significance of Triassic dolomite and cargneule in the Gran Paradiso region, Western Alps

Published online by Cambridge University Press:  01 May 2009

J. R. Vearncombe
J. R. Vearncombe
Affiliation:
Department of Earth Sciences, The Open Univeristy, Walton Hall Milton Keynes MK7 6AA, U.K.
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Summary

The interrelationships of dolomite, anhydrite, gypsum and cargneule (a yellow-brown dedolomitised breccia), are discussed with specific reference to the Gran Paradiso region, Western Alps. The dolomite is a highly deformed rock which occurs along the soles of both early and late-Alpine thrusts. Evidence suggests that cargneule formed late in the geological history of the region. It is suggested that dolomite + anhydrite + water acted as an important decollement horizon. Recent exposure to the surface, hydration of anhydrite to gypsum and dedolomitisation resulted in cargneule formation.

Type
Articles
Information
Geological Magazine , Volume 119 , Issue 3 , May 1982 , pp. 301 - 308
Copyright
Copyright © Cambridge University Press 1982

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