Generación de litosfera oceánica en ciclos de 100 Ma en peri-GondwanaOfiolitas de Marruecos e Iberia

  1. R. Arenas 1
  2. S. Sánchez Martínez 1
  3. R. Albert 2
  4. F. Haissen 3
  5. J. Fernández-Suárez 1
  6. N. Pujol-Solà 4
  7. P. Andonaegui 1
  8. R. Díez Fernández 1
  9. J.A. Proenza 4
  10. A. Garcia-Casco 5
  11. A. Gerdes 2
  1. 1 Universidad Complutense de Madrid
    info

    Universidad Complutense de Madrid

    Madrid, España

    ROR 02p0gd045

  2. 2 Institut für Geowissenschaften, Goethe-University Frankfurt
  3. 3 Université Hassan II de Casablanca
    info

    Université Hassan II de Casablanca

    Casablanca, Marruecos

    ROR https://ror.org/001q4kn48

  4. 4 Universitat de Barcelona
    info

    Universitat de Barcelona

    Barcelona, España

    ROR https://ror.org/021018s57

  5. 5 Universidad de Granada
    info

    Universidad de Granada

    Granada, España

    ROR https://ror.org/04njjy449

Revista:
Geotemas (Madrid)

ISSN: 1576-5172

Ano de publicación: 2021

Título do exemplar: X Congreso Geológico de España

Número: 18

Páxinas: 1041

Tipo: Artigo

Outras publicacións en: Geotemas (Madrid)

Resumo

The Variscan Orogen in Iberia and the Anti-Atlas mountains in Morocco contain a set of ophiolites formed between Neopro- terozoic and Devonian times during the complex evolution of the NW African margin of Gondwana. During this time interval the margin evolved from an active margin (c. 750-500 Ma, the Avalonian-Cadomian arc), to the final collision with Laurussia to form Pangea. In this context, different ophiolites have been dated at c. 700, 600, 500 and 400 Ma. The composition of all these peri-Gondwanan ophiolites is of supra-subduction zone type, showing no evidence for preserved MORB-type oceanic lithosphere. Consequently, these ophiolites were generated in the peri-Gondwanan realm during the opening of fore-arc or back-arc basins. The peri-Gondwanan realm has been a domain where generation of oceanic or transitional lithosphere seems to have occurred at intervals of c. 100 Ma. These regularly spaced time intervals may indicate cyclic events of mantle upwelling in the peri-Gondwanan mid-ocean ridges, with associated higher subduction rates at the peri-Gondwanan tren- ches and concomitant higher rates of partial melting in the associated mantle wedges.