Constraints on the late thermotectonic evolution of the Western Alps - Evidence for episodic rapid uplift
Details
Serval ID
serval:BIB_61D29BF7B349
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Constraints on the late thermotectonic evolution of the Western Alps - Evidence for episodic rapid uplift
Journal
Tectonics
ISSN-L
0278-7407
Publication state
Published
Issued date
1991
Peer-reviewed
Oui
Volume
10
Pages
758-769
Language
english
Notes
ISI:A1991GJ46100007
Abstract
Forty-two new apatite and zircon fission track ages are presented for
samples from the Western Alps in southern Switzerland, northern Italy,
and southeastern France. Measured ages plotted against assumed closure
temperatures yield cooling patterns for the final cooling, uplift, and
exhumation of the Western Alps. Similar fission track zircon ages in
the Penninic Gran Paradiso massif, Dent Blanche nappe, Sesia-Lanzo Zone,
and Ivrea Zone indicate cooling of all four units to approximately
225-degrees-C by 33 Ma. Differences in apatite ages reveal differential
cooling of the four blocks between 33 Ma and the present. In the
Sesia-Lanzo Zone, similarity of apatite ages regardless of elevation,
together with near-volcanic confined fission track length patterns
suggest rapid cooling and uplift at approximately 25 Ma compared with
slow cooling of other Western Alps units around 12 Ma. Uplift is thus
not continuous but episodic, often over a short time interval beyond the
resolution of other methods. Such episodes of uplift, as revealed here
in the Sesia-Lanzo Zone, may be the rule rather than the exception.
samples from the Western Alps in southern Switzerland, northern Italy,
and southeastern France. Measured ages plotted against assumed closure
temperatures yield cooling patterns for the final cooling, uplift, and
exhumation of the Western Alps. Similar fission track zircon ages in
the Penninic Gran Paradiso massif, Dent Blanche nappe, Sesia-Lanzo Zone,
and Ivrea Zone indicate cooling of all four units to approximately
225-degrees-C by 33 Ma. Differences in apatite ages reveal differential
cooling of the four blocks between 33 Ma and the present. In the
Sesia-Lanzo Zone, similarity of apatite ages regardless of elevation,
together with near-volcanic confined fission track length patterns
suggest rapid cooling and uplift at approximately 25 Ma compared with
slow cooling of other Western Alps units around 12 Ma. Uplift is thus
not continuous but episodic, often over a short time interval beyond the
resolution of other methods. Such episodes of uplift, as revealed here
in the Sesia-Lanzo Zone, may be the rule rather than the exception.
Create date
05/12/2012 20:20
Last modification date
20/08/2019 14:18