Dipartimento di Scienze della Terra

On a young Earth, chemosynthesis was the only mode of primary production - much unlike today where most life is based by photosynthesis. Among the few chemosynthesis-based environment in today's oceans are methane seeps, where a single biogeochemical process sustains mass occurrences of benthic metazoans and drives mineral authigenesis in the shallow subseafloor. After an introduction on the anaerobic oxidation of methane (AOM), the key biogeochemical process at seeps, I will discuss some recent developments in seep research, including (1) the formation of stromatolites, (2) coated grain formation and phosphorous cycling, (3) nitrogen cycling, (4) iron-driven AOM and magnetite formation, and (5) the ecology of dimerreloid brachiopods.

Speaker: Prof. Jörn Peckmann

After a doctorate from the lnstitut de Physique du Globe de Paris in 2003 and a post-doctorate at the University of Toronto (Canada), Alexandre Schubnel was recruited by CNRS in 2006 at the Laboratoire de Geologie of the Ecole normale superieure in Paris. There, he has strongly contributed to the establishment of a unique experi­ mental set-up of rock mechanics making it possible to cover the ranges of pressures and temperatures prevailing in the Earth's lithosphere. This set up enabled him to reproduce and "listen", in the laboratory, to the processes involved during the propagation of earthquakes, and, in particular, made it possible to better under­ stand the origin of deep earthquakes, which occur more than four hundred kilometers underground. In 2014, he was awarded the CNRS bronze medal and the Gouilloud-Schlumberger prize of the French Academy of Scienc­ es. In 2015, he was laureate of an ERC consolidator grant on the topic of "laboratory earthquakes''. Since 2019, he acts as the head of the Laboratoire de Geologie of the Ecole normale superieure de Paris.

Link to the Webinar:

https://unito.webex.com/unito-en/j.php?MTID=m41d6657a1aeac3bbe29b121b23ae9942

Contact: geoseminar.dst@unito.it