{"id":5424,"date":"2018-10-16T10:52:39","date_gmt":"2018-10-16T09:52:39","guid":{"rendered":"http:\/\/mdemierre.speleologie.ch\/?p=5424"},"modified":"2026-05-16T15:34:33","modified_gmt":"2026-05-16T14:34:33","slug":"speleologie-sous-glaciaire","status":"publish","type":"post","link":"https:\/\/www.techt.ch\/mdemierre\/?p=5424","title":{"rendered":"Grotte du bas-glacier d’Arolla"},"content":{"rendered":"

La tr\u00e8s grande majorit\u00e9 des cavit\u00e9s naturelles se d\u00e9veloppent dans le calcaire. Certaines se d\u00e9veloppe aussi en particulier dans le gypse, le sel, le marbre, la lave (tubes de lave) et aussi la glace<\/strong>.<\/p>\n

Bienvenue dans la glaciosp\u00e9l\u00e9ologie ! La glace a comme caract\u00e9ristique tout simplement fondre, plut\u00f4t que d’\u00eatre \u00e9rod\u00e9e (action m\u00e9canique) ou corrod\u00e9e (action chimique) comme les cavit\u00e9s karstiques. La glace fond sous l’action de l’eau et des courants d’air. Les sculptures en r\u00e9sultats sont tr\u00e8s esth\u00e9tiques. La glace est aussi transparente, laissant filtrer une surprenante lumi\u00e8re bleut\u00e9e lorsque la couche de glace est assez mince.<\/p>\n

Ces cavit\u00e9s sont accessibles depuis les pertes glaciaires que sont les moulins, des crevasses ou depuis l’exsurgence au front glaciaire. Des cavit\u00e9s int\u00e9ressantes se trouvent souvent dans les pertes des b\u00e9di\u00e8res (torrents en surface du glacier). Souvent, en plus du mat\u00e9riel classique de sp\u00e9l\u00e9ologie, des piolets, des crampons et des broches \u00e0 glaces sont n\u00e9cessaires pour progresser.<\/p>\n

A noter que les cavit\u00e9s sous-glaciaires \u00e9voluent rapidement, surtout \u00e0 cause du changement climatique. Les mouvements du glacier cr\u00e9er aussi des contraintes dans la glace et le risque d’effondrement incite \u00e0 la prudence. Les variations du d\u00e9bit d’eau sont aussi tr\u00e8s brutales. Les cavit\u00e9s sont en g\u00e9n\u00e9ral accessibles uniquement durant la saison froide, co\u00efncidant avec la baisse des d\u00e9bits dans le glacier.<\/p>\n

Une belle grotte se situait au bas-glacier d’Arolla. Quelques photographies (octobre 2018).
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\nL’entr\u00e9e s’est effondr\u00e9e en 2022, victime du changement climatique. Elle n’est plus accessible…<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

La tr\u00e8s grande majorit\u00e9 des cavit\u00e9s naturelles se d\u00e9veloppent dans le calcaire. Certaines se d\u00e9veloppe aussi en particulier dans le […]<\/p>\n","protected":false},"author":1,"featured_media":5427,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ngg_post_thumbnail":0,"footnotes":""},"categories":[8,83,109,10],"tags":[],"class_list":["post-5424","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cavites","category-explo-valais","category-sous-glaciaire","category-visite-suisse"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t