title: Ediacaran 2,500-km-long synchronous deep continental subduction in the West Gondwana Orogen.
abstract: The deeply eroded West Gondwana Orogen is a major continental collision zone that exposes numerous occurrences of deeply subducted rocks, such as eclogites. The position of these eclogites marks the suture zone between colliding cratons, and the age of metamorphism constrains the transition from subduction-dominated tectonics to continental collision and mountain building. Here we investigate the metamorphic conditions and age of high-pressure and ultrahigh-pressure eclogites from Mali, Togo and NE-Brazil and demonstrate that continental subduction occurred within 20 million years over at least a 2,500-km-long section of the orogen during the Ediacaran. We consider this to be the earliest evidence of large-scale deep-continental subduction and consequent appearance of Himalayan-scale mountains in the geological record. The rise and subsequent erosion of such mountains in the Late Ediacaran is perfectly timed to deliver sediments and nutrients that are thought to have been necessary for the subsequent evolution of sustainable life on Earth.
authors.affiliation: 1] Geological Survey of Brazil, Avenida Pasteur 404, CEP 22290-240, Rio de Janeiro, Brazil [2] Instituto de Geociências, Universidade de São Paulo, Rua do Lago, 562, CEP 05508-080, São Paulo, Brazil.
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Ganade de Araujo
authors.affiliation: Research School of Earth Sciences, Australian National University, Mills Road, Canberra 2610, Australia.
authors.forename: Daniela
authors.initials: D
authors.lastname: Rubatto
authors.affiliation: Research School of Earth Sciences, Australian National University, Mills Road, Canberra 2610, Australia.
authors.forename: Joerg
authors.initials: J
authors.lastname: Hermann
authors.affiliation: Instituto de Geociências, Universidade de São Paulo, Rua do Lago, 562, CEP 05508-080, São Paulo, Brazil.
authors.forename: Umberto G
authors.initials: UG
authors.lastname: Cordani
authors.affiliation: Géosciences Montpellier, Université de Montpellier II, Place E. Bataillon 34095, Montpellier CEDEX 5, France.
authors.forename: Renaud
authors.initials: R
authors.lastname: Caby
authors.affiliation: Instituto de Geociências, Universidade de São Paulo, Rua do Lago, 562, CEP 05508-080, São Paulo, Brazil.
authors.forename: Miguel A S
authors.initials: MA
authors.lastname: Basei