{"id":14722,"date":"2026-06-10T10:50:15","date_gmt":"2026-06-10T08:50:15","guid":{"rendered":"https:\/\/wp.unil.ch\/geoblog\/?p=14722"},"modified":"2026-06-10T10:50:49","modified_gmt":"2026-06-10T08:50:49","slug":"integrated-biostratigraphic-chemostratigraphic-and-cyclostratigraphic-approaches-to-the-miaolingian-epoch-implications-for-global-correlations-and-cambrian-timescale-refinement","status":"publish","type":"post","link":"https:\/\/wp.unil.ch\/geoblog\/2026\/06\/integrated-biostratigraphic-chemostratigraphic-and-cyclostratigraphic-approaches-to-the-miaolingian-epoch-implications-for-global-correlations-and-cambrian-timescale-refinement\/","title":{"rendered":"Integrated biostratigraphic, chemostratigraphic, and cyclostratigraphic approaches to the Miaolingian Epoch: implications for global correlations and Cambrian timescale refinement"},"content":{"rendered":"<figure class=\"wp-block-post-featured-image\"><img loading=\"lazy\" decoding=\"async\" width=\"898\" height=\"1200\" src=\"https:\/\/wp.unil.ch\/geoblog\/files\/2026\/06\/cambrien.jpg\" class=\"attachment-post-thumbnail size-post-thumbnail wp-post-image\" alt=\"cambrien\" style=\"object-fit:cover;\" srcset=\"https:\/\/wp.unil.ch\/geoblog\/files\/2026\/06\/cambrien.jpg 898w, https:\/\/wp.unil.ch\/geoblog\/files\/2026\/06\/cambrien-225x300.jpg 225w, https:\/\/wp.unil.ch\/geoblog\/files\/2026\/06\/cambrien-766x1024.jpg 766w, https:\/\/wp.unil.ch\/geoblog\/files\/2026\/06\/cambrien-768x1026.jpg 768w\" sizes=\"auto, (max-width: 898px) 100vw, 898px\" \/><\/figure>\n\n\n<div class=\"wp-block-group has-accent-5-background-color has-background has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\">\n<p class=\"has-accent-5-background-color has-text-color has-background has-link-color wp-elements-19362f2b45677413e41c40cd7f0ad4ec wp-block-paragraph\" style=\"color:#212121;font-size:clamp(14px, 0.875rem + ((1vw - 3.2px) * 0.49), 19px);\"><em>Th\u00e8se en sciences de la Terre, soutenue le 26 juin 2026 par Valentin Jamart, rattach\u00e9 \u00e0 l&rsquo;Institut des sciences de la Terre (ISTE) de la FGSE.<\/em><\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Le Cambrien est une p\u00e9riode g\u00e9ologique s\u2019\u00e9tendant de &#8211; 539 \u00e0 &#8211; 487 millions d\u2019ann\u00e9es. Cette p\u00e9riode recul\u00e9e \u00e9tait tr\u00e8s diff\u00e9rente de ce que nous connaissons aujourd\u2019hui. En particulier, la disposition des continents n\u2019avait rien \u00e0 voir avec celle repr\u00e9sent\u00e9e sur les cartes actuelles : la majeure partie des masses continentales \u00e9tait situ\u00e9e entre les tropiques.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Par ailleurs, les continents aujourd\u2019hui verdoyants \u00e9taient d\u00e9pourvus de vie durant le Cambrien, celle-ci n\u2019ayant pas encore \u00e9volu\u00e9 les capacit\u00e9s n\u00e9cessaires \u00e0 la colonisation de ces environnements. Ainsi, la vie multicellulaire complexe \u00e9tait exclusivement marine. D\u2019un point de vue atmosph\u00e9rique, le niveau d\u2019oxyg\u00e8ne \u00e9tait d\u2019environ 10 % de celui que nous connaissons actuellement.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Au cours de cette p\u00e9riode, de nombreux changements fondamentaux sont observ\u00e9s, notamment des variations climatiques majeures ayant perturb\u00e9 le cycle du carbone. L\u2019un de ces \u00e9v\u00e9nements, commun\u00e9ment appel\u00e9 \u00ab explosion cambrienne \u00bb, correspond \u00e0 une apparition relativement rapide et \u00e0 une diversification importante des principaux groupes animaux. Bien que cette p\u00e9riode constitue un moment cl\u00e9 dans l\u2019histoire de la vie sur Terre, de nombreux obstacles limitent encore notre compr\u00e9hension d\u00e9taill\u00e9e de son d\u00e9roulement et de ses impacts.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Parmi ceux-ci figurent le manque de contraintes temporelles pr\u00e9cises et la difficult\u00e9 de corr\u00e9ler les enregistrements g\u00e9ologiques entre les continents. L\u2019\u00e9tude d\u2019une coupe g\u00e9ologique dans le sud de la France ainsi que celle d\u2019un carottage r\u00e9alis\u00e9 en Su\u00e8de m\u2019ont permis de r\u00e9pondre en partie aux questions relatives aux corr\u00e9lations entre des localit\u00e9s situ\u00e9es en dehors des tropiques au Cambrien moyen. Par ailleurs, l\u2019\u00e9tude scandinave a mis en \u00e9vidence l\u2019importance des fluctuations climatiques dans les m\u00e9canismes de transport des s\u00e9diments vers l\u2019oc\u00e9an aux hautes latitudes de l\u2019h\u00e9misph\u00e8re sud durant cette p\u00e9riode.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Enfin, l\u2019utilisation de m\u00e9thodes statistiques modernes appliqu\u00e9es \u00e0 une compilation des \u00e2ges disponibles dans la litt\u00e9rature, combin\u00e9 \u00e0 une r\u00e9vision des cadres biologiques et chimiques, a permis de proposer une r\u00e9vision de l\u2019\u00e9chelle temporelle du Cambrien. Cela fournit ainsi un cadre chronologique plus robuste pour de futures \u00e9tudes visant \u00e0 r\u00e9duire davantage les incertitudes relatives aux \u00e9v\u00e9nements majeurs ayant marqu\u00e9 cette p\u00e9riode.\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Th\u00e8se en sciences de la Terre<\/p>\n","protected":false},"author":47,"featured_media":14723,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"","_seopress_news_disabled":"","_seopress_video_disabled":"","_seopress_video":[],"_seopress_pro_schemas_manual":[],"_seopress_pro_rich_snippets_disable_all":"","_seopress_pro_rich_snippets_disable":[],"_seopress_pro_schemas":[],"footnotes":"","_links_to":"","_links_to_target":""},"categories":[49465],"tags":[],"class_list":["post-14722","post","type-post","status-publish","format-standard","has-post-thumbnail","category-theses-soutenues"],"_links":{"self":[{"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts\/14722","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/users\/47"}],"replies":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/comments?post=14722"}],"version-history":[{"count":1,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts\/14722\/revisions"}],"predecessor-version":[{"id":14725,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts\/14722\/revisions\/14725"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/media\/14723"}],"wp:attachment":[{"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/media?parent=14722"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/categories?post=14722"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/tags?post=14722"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}