RT Journal Article
T1 A complex accretionary assembly of Pangea developed in the range c. 400–340 Ma: the four successive events of high-P/ultra-high-P metamorphism of the Variscan Orogen
A1 Novo Fernández, Irene
A1 Arenas Martín, Ricardo
A1 Díez Fernández, Rubén
A1 Garcia Casco, Antonio
AB In the most internal zone of the Variscan Orogen, a stack of ophiolites and (ultra)high-P belts hold evidence for c. 60 Myr (c. 400–340 Ma) of almost continuous metamorphism and accretion onto the continental margin of Gondwana. Subduction of the peri-Gondwanan lithosphere led to three successive (ultra)high-P metamorphic episodes prior to the continental collision between Gondwana and Laurussia that shaped Pangea. A first high-P, high-T metamorphic belt developed during subduction of a peri-Gondwanan magmatic arc in the Early Devonian. Related to this event is the ensuing opening of intra-Gondwana Middle Devonian oceanic basins, which rapidly closed leading to ophiolite accretion. The second high-P metamorphic episode is related to the formation of a serpentinitic mélange after the sequential subduction of oceanic and transitional crust during Middle Devonian time. Tectonic blocks of subducted crustal material recording high-P, low-T metamorphism were detached from the slab and incorporated into a low-viscosity channel developed between the downgoing slab and the mantle wedge. As convergence progressed, a Late Devonian high-P, low- to intermediate-T metamorphic belt developed due to subduction of the most external margin of Gondwana. Subsequently, the scenario switched to continental collision. In this context, Early Carboniferous intracontinental subduction of the Gondwanan foreland below the accretionary wedge triggered ultra-high-P metamorphism and ensuing exhumation via trans-lithospheric diapirism and doming up to the base of the accretionary wedge.
PB Taylor & Francis
SN 0020-6814
YR 2022
FD 2022-10-09
LK https://hdl.handle.net/20.500.14352/72543
UL https://hdl.handle.net/20.500.14352/72543
LA eng
NO Ministerio de Ciencia e Innovación (MICINN)
DS Docta Complutense
RD 23 jul 2024