{"id":28506,"date":"2026-08-28T11:01:31","date_gmt":"2026-08-28T09:01:31","guid":{"rendered":"https:\/\/lpg-umr6112.fr\/?post_type=tribe_events&p=28506"},"modified":"2026-09-25T14:32:10","modified_gmt":"2026-09-25T12:32:10","slug":"seminar","status":"publish","type":"tribe_events","link":"https:\/\/lpg-umr6112.fr\/en\/event\/seminar\/","title":{"rendered":"Seminar by Axel Noblet (University of Western Ontario) – “Martian gullies: exploring their surface signatures to unravel their origin”"},"content":{"rendered":"

Since the year 2000, mysterious Martian landforms named ‘gullies’ have been at the center of a debate regarding their origin. Understanding how gullies formed will unlock key knowledge about Mars’ recent climate, the interactions of H2O and CO2 with the surface and the potential for habitable environments on Mars in the last few million years. In this seminar, I will present the results of my PhD research: I will begin by presenting a newly spatially resolved global catalog of more than 8,000 gullied hillslopes that enables the comparison of gully distribution with km-scale global datasets for the first time. Second, I will present the first global map of gully-susceptibility for Mars, which allowed me to discover intriguing regional trends in the distribution of gullies. Finally, I present the results of a morphometrical analysis of gully alcoves that show which suggests that long-term evolution of slopes within gullies is driven by seasonal frost activity on pole-facing slopes, rather than by melting of water ice on equator-facing slopes.<\/p>\n

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Depuis l’an 2000, des formations g\u00e9ologiques martiennes myst\u00e9rieuses appel\u00e9es \u00ab gullies \u00bb font l’objet d’un d\u00e9bat quant \u00e0 leur origine. Comprendre comment ces ravines se sont form\u00e9es permettra d’acqu\u00e9rir des connaissances essentielles sur le climat r\u00e9cent de Mars, les interactions entre l’H\u2082O et le CO\u2082 avec la surface, ainsi que le potentiel d’environnements habitables sur Mars au cours des derniers millions d’ann\u00e9es. Au cours de ce s\u00e9minaire, je pr\u00e9senterai les r\u00e9sultats de ma th\u00e8se de doctorat : je commencerai par pr\u00e9senter un nouveau catalogue global \u00e0 haute r\u00e9solution spatiale recensant plus de 8 000 pentes pr\u00e9sentant des ravines, qui permet pour la premi\u00e8re fois de comparer la r\u00e9partition de ces ravines avec des ensembles de donn\u00e9es globaux \u00e0 l’\u00e9chelle du kilom\u00e8tre. Ensuite, je pr\u00e9senterai la premi\u00e8re carte globale de la susceptibilit\u00e9 \u00e0 la formation de ravines sur Mars, qui m’a permis de mettre en \u00e9vidence des tendances r\u00e9gionales intrigantes dans la r\u00e9partition de ces formations. Enfin, je pr\u00e9senterai les r\u00e9sultats d’une analyse morphom\u00e9trique des alc\u00f4ves des ravines, qui sugg\u00e8rent que l’\u00e9volution \u00e0 long terme des pentes au sein des ravines est d\u00e9termin\u00e9e par l’activit\u00e9 saisonni\u00e8re du gel sur les pentes orient\u00e9es vers les p\u00f4les, plut\u00f4t que par la fonte de la glace d’eau sur les pentes orient\u00e9es vers l’\u00e9quateur.<\/p>\n","protected":false},"excerpt":{"rendered":"

Since the year 2000, mysterious Martian landforms named ‘gullies’ have been at the center of a debate regarding their origin. Understanding how gullies formed will unlock key knowledge about Mars’ […]<\/p>\n","protected":false},"author":172,"featured_media":0,"template":"","meta":{"_acf_changed":false,"_price":"","_stock":"","_tribe_ticket_header":"","_tribe_default_ticket_provider":"","_tribe_ticket_capacity":"0","_ticket_start_date":"","_ticket_end_date":"","_tribe_ticket_show_description":"","_tribe_ticket_show_not_going":false,"_tribe_ticket_use_global_stock":"","_tribe_ticket_global_stock_level":"","_global_stock_mode":"","_global_stock_cap":"","_tribe_rsvp_for_event":"","_tribe_ticket_going_count":"","_tribe_ticket_not_going_count":"","_tribe_tickets_list":"[]","_tribe_ticket_has_attendee_info_fields":false,"_tribe_events_status":"","_tribe_events_status_reason":"","_tribe_events_is_hybrid":"","_tribe_events_is_virtual":"","_tribe_events_virtual_video_source":"","_tribe_events_virtual_embed_video":"","_tribe_events_virtual_linked_button_text":"","_tribe_events_virtual_linked_button":"","_tribe_events_virtual_show_embed_at":"","_tribe_events_virtual_show_embed_to":[],"_tribe_events_virtual_show_on_event":"","_tribe_events_virtual_show_on_views":"","_tribe_events_virtual_url":"","footnotes":"","_tec_slr_enabled":"","_tec_slr_layout":""},"tags":[],"tribe_events_cat":[25,23,22],"coauthors":[252],"class_list":["post-28506","tribe_events","type-tribe_events","status-publish","hentry","tribe_events_cat-amphitheatre","tribe_events_cat-evenements","tribe_events_cat-seminaires","cat_amphitheatre","cat_evenements","cat_seminaires"],"acf":[],"ticketed":false,"_links":{"self":[{"href":"https:\/\/lpg-umr6112.fr\/en\/wp-json\/wp\/v2\/tribe_events\/28506","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lpg-umr6112.fr\/en\/wp-json\/wp\/v2\/tribe_events"}],"about":[{"href":"https:\/\/lpg-umr6112.fr\/en\/wp-json\/wp\/v2\/types\/tribe_events"}],"author":[{"embeddable":true,"href":"https:\/\/lpg-umr6112.fr\/en\/wp-json\/wp\/v2\/users\/172"}],"version-history":[{"count":4,"href":"https:\/\/lpg-umr6112.fr\/en\/wp-json\/wp\/v2\/tribe_events\/28506\/revisions"}],"predecessor-version":[{"id":29264,"href":"https:\/\/lpg-umr6112.fr\/en\/wp-json\/wp\/v2\/tribe_events\/28506\/revisions\/29264"}],"wp:attachment":[{"href":"https:\/\/lpg-umr6112.fr\/en\/wp-json\/wp\/v2\/media?parent=28506"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lpg-umr6112.fr\/en\/wp-json\/wp\/v2\/tags?post=28506"},{"taxonomy":"tribe_events_cat","embeddable":true,"href":"https:\/\/lpg-umr6112.fr\/en\/wp-json\/wp\/v2\/tribe_events_cat?post=28506"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/lpg-umr6112.fr\/en\/wp-json\/wp\/v2\/coauthors?post=28506"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}