Eventi, distinguished lectures e seminari

Subduction hides ultra-deep sources of energy.

Alberto Vitale Brovarone - Dipartimento di Scienze Biologiche, Geologiche e Ambientali

Alma Mater Studiorum Università di Bologna

Abstract

By regulating the exchanges of carbon and water between the surface and the deep Earth, subduction has played a central role in the evolution of our planet and the formation and preservation of habitable conditions. The last decade has witnessed extensive efforts in deciphering key missing tiles of the deep carbon and water cycles at convergent margins and the mechanisms through which they participate in global geo-biological equilibria. Most of the current knowledge about the deep carbon cycle and subduction relies on the cycle of deep CO₂ and H₂O, from their formation through metamorphic reactions to volcanic degassing. However, much less is known about the role of more reduced and energetic fluid species, such as CH4 and H2, in subduction zone processes.

This seminar will explore the reduced far side of subduction. A general introduction on geological CH₄ and H₂ genesis will be presented, followed by recent results suggesting that subduction may have hosted the largest sources of this deep energy on Earth from the beginning of plate tectonics. 

Biosketch

Alberto Vitale Brovarone obtained a binational PhD in Earth Sciences at the Universities of Torino and Montpellier (France). During the PhD he studied the high-pressure tectono-metamorphic evolution of the subducted Tethyan hyper-extended passive margins preserved in Alpine Corsica. He conducted one year of post-doctoral research at ISTeP (Univiersité Pierre et Marie Curie, now Sorbonne Université), on the tectono-metamorphic evolution of New Caledonia, and then two years of post-doctoral research at IMPMC (Sorbonne Université) on high-pressure metasomatism and mass transfer in Alpine Corsica. He obtained a permanent position at the French CNRS, based at IMPMC, where he started investigating deep carbon recycling in subduction zones. For this research, he was awarded the Emerging Leader Award by the Deep Carbon Observatory. He was a recipient of the MIUR Rita Levi Montalcini program that he conducted at DST, University of Torino. He was recently awarded the ERC Consolidator grant DeepSeep on deep serpentinization, H₂, and abiotic CH₄. From 2020, he is Full Professor in petrology at BiGeA, University of Bologna.