Chronology, petrogenesis and heat sources for successive Carboniferous magmatic events in the Southern–Central Variscan Vosges
Mts (NE France)
Anne-Sophie Tabaud
Vojtěch Janoušek
Etienne Skrzypek
Karel Schulmann
Philippe Rossi
Hubert Whitechurch
Catherine Guerrot
Jean-Louis Paquette
10.6084/m9.figshare.3453860.v1
https://geolsoc.figshare.com/articles/dataset/Chronology_petrogenesis_and_heat_sources_for_successive_Carboniferous_magmatic_events_in_the_Southern_Central_Variscan_Vosges___Mts_NE_France_/3453860
<p>Plutonic bodies of the Central and Southern Vosges Mts can be assigned to two major early Carboniferous magmatic events: a
Visean Mg–K event (<em>c.</em> 345 and 340–336 Ma) and a younger S-type event (329–322 Ma). New petrological, geochemical and Sr–Nd isotopic data highlight
the existence of two groups of Mg–K intrusions that might be related to the nature of their primary magma sources; that is,
CHUR-like and enriched mantle, which interacted with juvenile and mature crustal material, respectively. The differences between
these two groups are explained by a geodynamic scenario involving deep subduction and relamination of the Saxothuringian continental
crust under the Moldanubian continent. The relaminated radiogenic Saxothuringian material is thought to have been responsible
for dehydration melting of both subducted crust and underlying metasomatized mantle, thereby generating the Mg–K magma subsequently
emplaced at middle crustal depth. During their ascent, the mafic magmas interacted with crustally derived felsic melts. Significantly
later (<em>c</em>. 10–15 myr) a widespread mid-crustal anatexis occurred, generating voluminous granite intrusions from mixed crustal sources
(paragneisses and/or immature felsic–intermediate metaigneous rocks mixed with Mg–K plutons). The principal heat source for
such a major melting event is related to the presence of Mg–K plutons rich in heat-producing elements, which were responsible,
after the time lag specified, for a temperature increase at mid-crustal levels by <em>in situ</em> radiogenic heat production. The current study underlines the importance of deep continental crust subduction and relamination
for the magmatism and development of collisional orogens.
</p>
2016-06-21 11:43:41
geodynamic scenario
metasomatized mantle
subducted crust
granite intrusions
collisional orogens
mafic magmas interacted
Plutonic bodies
radiogenic heat production
pluton
Mg
Ma
NE France
crustal material
relaminated radiogenic Saxothuringian material
crustal sources
Southern Vosges Mts
heat source
Moldanubian continent
middle crustal depth
relamination
New petrological
crust subduction
felsic
heat sources
temperature increase
Carboniferous magmatic events
magma sources
Geology