scholarly journals Vegetation geoseries of the Ortles-Cevedale massif (central Alps, Italy) and their phytogeographic significanc

Bocconea ◽  
2021 ◽  
Vol 29 ◽  
Keyword(s):  
2009 ◽  
Vol 45 (3) ◽  
pp. 204-207 ◽  
Author(s):  
Rosangela Bocchio ◽  
Ilaria Adamo ◽  
Franca Caucia
Keyword(s):  

2017 ◽  
Vol 721 ◽  
pp. 179-195 ◽  
Author(s):  
Alfons Berger ◽  
Philip Wehrens ◽  
Pierre Lanari ◽  
Horst Zwingmann ◽  
Marco Herwegh

1991 ◽  
Vol 198 (1) ◽  
pp. 53-72 ◽  
Author(s):  
P. Passerini ◽  
G. Sguazzoni ◽  
M. Marcucci
Keyword(s):  

Geosphere ◽  
2020 ◽  
Vol 16 (2) ◽  
pp. 510-532
Author(s):  
Paraskevi Io Ioannidi ◽  
Samuel Angiboust ◽  
Onno Oncken ◽  
Philippe Agard ◽  
Johannes Glodny ◽  
...  

Abstract A network of fossil subduction plate interfaces preserved in the Central Alps (Val Malenco, N Italy) is herein used as a proxy to study deformation processes related to subduction and subsequent underplating of continental slices (in particular the Margna and Sella nappes) at depths reported to in the former brittle-ductile transition. Field observations, microfabrics, and mapping revealed a network of shear zones comprising mostly mylonites and schists but also rare foliated cataclasites. These shear zones are either located at the contacts of the two nappes or within the boundaries of the Sella unit. Microprobe results point to two different white mica generations, with higher-pressure (Si-rich) phengites rimming lower-pressure (Si-poor) phengites. Garnet is locally observed overgrowing resorbed pre-Alpine cores. Pressure-temperature estimates based on pseudosection modeling point to peak burial deformation conditions of ∼0.9 GPa and 350–400 °C, at ∼30 km depth. Rb/Sr geochronology on marbles deformed during the Alpine event yields an age of 48.9 ± 0.9 Ma, whereas due to incomplete recrystallization, a wide range of both Rb/Sr and 40Ar/39Ar apparent ages is obtained from deformed orthogneisses and micaschists embracing 87–44 Ma. Based on our pressure-temperature, structural and geochronological observations, the studied shear zones last equilibrated at depths downdip of the seismogenic zone in an active subduction zone setting. We integrate these new results in the frame of previous studies on other segments of the same Alpine paleosubduction interface, and we propose that this system of shear zones represents deformation conditions along the subduction interface(s) in the transition zone below the seismogenic zone during active subduction.


2000 ◽  
Vol 12 (6) ◽  
pp. 1245-1260 ◽  
Author(s):  
Sakiko N. Olsen ◽  
Clark M. Johnson ◽  
Brian L. Beard ◽  
Lukas P. Baumgartner

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