{"id":11202,"date":"2024-02-07T11:13:11","date_gmt":"2024-02-07T10:13:11","guid":{"rendered":"https:\/\/wp.unil.ch\/geoblog\/?p=11202"},"modified":"2024-02-07T11:17:28","modified_gmt":"2024-02-07T10:17:28","slug":"quaternary-evolution-of-an-african-high-plateau-the-chobe-enclave-northen-botswana","status":"publish","type":"post","link":"https:\/\/wp.unil.ch\/geoblog\/2024\/02\/quaternary-evolution-of-an-african-high-plateau-the-chobe-enclave-northen-botswana\/","title":{"rendered":"Quaternary evolution of an African High Plateau: The Chobe Enclave (Northen Botswana)\u00a0"},"content":{"rendered":"\n

Th\u00e8se en sciences de la Terre, soutenue le 21 f\u00e9vrier 2024 par Thuto Mokatse, rattach\u00e9 \u00e0 l’Institut des dynamiques de la surface terrestre (IDYST) de la FGSE.<\/em><\/p>\n\n\n\n

\"\"<\/a><\/figure>\n\n\n\n

L’\u00e9tude s\u2019est concentr\u00e9e sur la Chobe Enclave situ\u00e9e dans le nord du Botswana, o\u00f9 l’impact de la tectonique est souvent brouill\u00e9 par des couvertures s\u00e9dimentaires mobiles, rendant difficile toute reconstruction pal\u00e9o-environnementale d\u00e9taill\u00e9e. Une combinaison de lev\u00e9s g\u00e9ophysiques de surface, d’analyses s\u00e9dimentologiques et de datations par luminescence stimul\u00e9e optiquement a \u00e9t\u00e9 utilis\u00e9e pour \u00e9tudier la relation entre le d\u00e9veloppement du paysage et l’activit\u00e9 tectonique.<\/p>\n\n\n\n

La Chobe Enclave fait partie du sous-bassin Chobe-Linyanti, une d\u00e9pression structurale d\u00e9limit\u00e9e par des syst\u00e8mes de failles, cruciale pour sa configuration \u00e9volutive. L’\u00e9tude a r\u00e9v\u00e9l\u00e9 la transition d’un environnement fluviatile\/\u00e9olien \u00e0 un environnement lacustre\/palustre, avec la formation de carbonates et de diatomites. Des \u00e9v\u00e9nements tectoniques ont entra\u00een\u00e9 l’ensevelissement de chenaux fluviaux, l’\u00e9l\u00e9vation syn-s\u00e9dimentaire de cr\u00eates sableuses et la formation d\u2019entailles de surimposition fluviales. Les changements hydrog\u00e9ochimiques du Pl\u00e9istoc\u00e8ne sup\u00e9rieur \u00e0 l’Holoc\u00e8ne ont permis la formation de s\u00e9piolite authig\u00e8ne (une argile fibreuse), dans un contexte \u00e9vaporitique.<\/p>\n\n\n\n

L’\u00e9tude au travers des relations min\u00e9ralogiques entre faci\u00e8s et des microtextures associ\u00e9es aux grains de quartz, a pu r\u00e9v\u00e9ler l\u2019histoire complexe d’un ancien c\u00f4ne alluvial influenc\u00e9 par des changements hydrologiques combin\u00e9s \u00e0 des phases \u00e9oliennes, fluviales, palustres et d’alt\u00e9ration multiples.<\/p>\n","protected":false},"excerpt":{"rendered":"

Th\u00e8se en sciences de la Terre, soutenue le 21 f\u00e9vrier 2024 par Thuto Mokatse, rattach\u00e9 \u00e0 l’Institut des dynamiques de la surface terrestre (IDYST) de la FGSE. L’\u00e9tude s\u2019est concentr\u00e9e sur la Chobe Enclave situ\u00e9e dans le nord du Botswana, o\u00f9 l’impact de la tectonique est souvent brouill\u00e9 par des couvertures s\u00e9dimentaires mobiles, rendant difficile […]<\/p>\n","protected":false},"author":47,"featured_media":11203,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"","_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","footnotes":"","_links_to":"","_links_to_target":""},"categories":[49465],"tags":[],"class_list":{"0":"post-11202","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-theses-soutenues"},"_links":{"self":[{"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts\/11202","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=11202"}],"version-history":[{"count":1,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts\/11202\/revisions"}],"predecessor-version":[{"id":11205,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts\/11202\/revisions\/11205"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/media\/11203"}],"wp:attachment":[{"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/media?parent=11202"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/categories?post=11202"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/tags?post=11202"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}