{"id":504,"date":"2026-05-26T19:34:43","date_gmt":"2026-05-26T17:34:43","guid":{"rendered":"https:\/\/ssnhs17.fr\/?p=504"},"modified":"2026-05-26T19:35:42","modified_gmt":"2026-05-26T17:35:42","slug":"week-end-geologique-de-pentecote-aux-portes-de-la-bretagne","status":"publish","type":"post","link":"https:\/\/ssnhs17.fr\/?p=504","title":{"rendered":"Week-end g\u00e9ologique de Pentec\u00f4te aux portes de la Bretagne"},"content":{"rendered":"\n<p>\u00c0 l\u2019occasion du week-end de Pentec\u00f4te, nous avons pass\u00e9 quatre jours \u00e0 d\u00e9couvrir une partie du socle hercynien du sud de la Bretagne historique, entre le sud de Nantes et la r\u00e9gion de Rennes. Ce voyage m\u00ealait g\u00e9ologie, patrimoine minier et histoire m\u00e9di\u00e9vale, avec plusieurs \u00e9tapes marquantes.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u00c0 la recherche des \u00e9clogites \u00e0 Saint-Philbert-de-Bouaine<\/h3>\n\n\n\n<p>Notre premi\u00e8re matin\u00e9e nous a conduits \u00e0 la carri\u00e8re de Saint-Philbert-de-Bouaine, en Vend\u00e9e, c\u00e9l\u00e8bre chez les amateurs de min\u00e9raux pour ses \u00e9clogites riches en grenats. Ces roches m\u00e9tamorphiques se sont form\u00e9es \u00e0 grande profondeur, sous de tr\u00e8s fortes pressions, lors de la collision des continents pendant l\u2019orogen\u00e8se hercynienne il y a environ 350 \u00e0 400 millions d\u2019ann\u00e9es.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260522_084319606-1024x576.jpg\" alt=\"\" class=\"wp-image-530\" srcset=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260522_084319606-1024x576.jpg 1024w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260522_084319606-300x169.jpg 300w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260522_084319606-768x432.jpg 768w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260522_084319606-1536x864.jpg 1536w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260522_084319606-2048x1152.jpg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Carri\u00e8re de Saint-Philbert-de-Bouaine<\/figcaption><\/figure>\n\n\n\n<p>Les \u00e9clogites sont particuli\u00e8rement reconnaissables \u00e0 leurs grenats rouges, ros\u00e9s, parfois aur\u00e9ol\u00e9s de noir, inclus dans une matrice verte riche en omphacite. Nous avons eu la chance d\u2019y d\u00e9couvrir \u00e9galement une belle plaque de disth\u00e8ne (ou cyanite), min\u00e9ral bleu se formant lui aussi dans des conditions de m\u00e9tamorphisme intense.<\/p>\n\n\n\n<div id=\"wp-block-themeisle-blocks-slider-8edb597f\" class=\"wp-block-themeisle-blocks-slider glide\" data-per-view=\"1\" data-gap=\"0\" data-peek=\"0\" data-autoplay=\"true\" data-height=\"400px\" data-hide-arrows=\"false\"><div class=\"glide__track\" data-glide-el=\"track\"><div class=\"glide__slides\"><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260522_095625295-scaled.jpg\" alt=\"\" title=\"\" data-id=\"529\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260522_093920623-scaled.jpg\" alt=\"\" title=\"\" data-id=\"528\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260522_093944969-scaled.jpg\" alt=\"\" title=\"\" data-id=\"527\"\/><\/figure><\/div><\/div><div class=\"glide__bullets\" data-glide-el=\"controls[nav]\"><button class=\"glide__bullet\" data-glide-dir=\"=0\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=1\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=2\"><\/button><\/div><\/div><\/div>\n\n\n\n<p>L\u2019apr\u00e8s-midi fut consacr\u00e9e \u00e0 la recherche d\u2019\u00e9clogites dans les vignes voisines, o\u00f9 les labours font parfois remonter de beaux blocs \u00e0 la surface.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Trilobites de La No\u00eb Blanche<\/h3>\n\n\n\n<p>Le samedi 23 mai, nous avons eu l&rsquo;autorisation de prospecter dans une petite carri\u00e8re exploit\u00e9e autrefois par un agriculteur de La No\u00eb Blanche. Le site est connu pour ses schistes de l\u2019Ordovicien moyen, vieux d\u2019environ 470 millions d\u2019ann\u00e9es.<\/p>\n\n\n\n<div id=\"wp-block-themeisle-blocks-slider-65adc1c1\" class=\"wp-block-themeisle-blocks-slider glide\" data-per-view=\"1\" data-gap=\"0\" data-peek=\"0\" data-autoplay=\"true\" data-height=\"400px\" data-hide-arrows=\"false\"><div class=\"glide__track\" data-glide-el=\"track\"><div class=\"glide__slides\"><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260523_113301065-scaled.jpg\" alt=\"\" title=\"\" data-id=\"510\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260523_103256856-1-scaled.jpg\" alt=\"\" title=\"\" data-id=\"511\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260523_090047616.LONG_EXPOSURE-scaled.jpg\" alt=\"\" title=\"\" data-id=\"509\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260523_085322817-scaled.jpg\" alt=\"\" title=\"\" data-id=\"512\"\/><\/figure><\/div><\/div><div class=\"glide__bullets\" data-glide-el=\"controls[nav]\"><button class=\"glide__bullet\" data-glide-dir=\"=0\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=1\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=2\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=3\"><\/button><\/div><\/div><\/div>\n\n\n\n<p>Ces schistes feuillet\u00e9s, qui se d\u00e9bitent en fines plaques ressemblant parfois \u00e0 des \u201cfrites\u201d, peuvent contenir des fossiles marins comme notamment des trilobites. Ces arthropodes aujourd\u2019hui disparus vivaient dans les oc\u00e9ans pal\u00e9ozo\u00efques bien avant les dinosaures. Nous remontons loin dans l\u2019histoire g\u00e9ologique r\u00e9gionale, \u00e0 une \u00e9poque o\u00f9 la Bretagne se trouvait sous des mers tropicales. Nous avons \u00e9galement trouv\u00e9s des bivalves et des bellerophons.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"473\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260523_170311-1-1024x473.jpg\" alt=\"\" class=\"wp-image-514\" srcset=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260523_170311-1-1024x473.jpg 1024w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260523_170311-1-300x139.jpg 300w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260523_170311-1-768x355.jpg 768w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260523_170311-1-1536x709.jpg 1536w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260523_170311-1-2048x946.jpg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Trilobite de la No\u00e9 Blanche<\/figcaption><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">Les terrils miniers d\u2019Abbaretz et la cassit\u00e9rite<\/h3>\n\n\n\n<p>Nous avons ensuite explor\u00e9 les terrils de l\u2019ancienne mine d\u2019\u00e9tain d\u2019Abbaretz. Exploit\u00e9e principalement au XXe si\u00e8cle, cette mine faisait partie des rares grands sites fran\u00e7ais de production d\u2019\u00e9tain. <\/p>\n\n\n\n<p>Le minerai recherch\u00e9 ici est la cassit\u00e9rite, principal minerai d\u2019\u00e9tain, reconnaissable \u00e0 sa densit\u00e9 \u00e9lev\u00e9e et \u00e0 sa couleur sombre brun-noir. Les terrils t\u00e9moignent encore aujourd\u2019hui de cette importante activit\u00e9 mini\u00e8re. Le site est d\u00e9sormais largement grillag\u00e9 afin d\u2019assurer la s\u00e9curit\u00e9 des visiteurs.<\/p>\n\n\n\n<p>Au-del\u00e0 de l\u2019aspect min\u00e9ralogique, le paysage conserve une atmosph\u00e8re industrielle particuli\u00e8re, rare dans l\u2019ouest de la France.<\/p>\n\n\n\n<figure class=\"wp-block-image alignwide size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260523_134050071-1024x576.jpg\" alt=\"\" class=\"wp-image-507\" srcset=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260523_134050071-1024x576.jpg 1024w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260523_134050071-300x169.jpg 300w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260523_134050071-768x432.jpg 768w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260523_134050071-1536x864.jpg 1536w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260523_134050071-2048x1152.jpg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Vue du haut du Terril d&rsquo;Abbaretz<\/figcaption><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">Visite du ch\u00e2teau de Ch\u00e2teaubriant<\/h3>\n\n\n\n<p>Le dimanche, apr\u00e8s un second passage \u00e0 la Noe Blanche, nous avons poursuivi notre voyage par la visite du ch\u00e2teau de Ch\u00e2teaubriant, qui pr\u00e9sente deux ensembles architecturaux et plusieurs si\u00e8cles d\u2019histoire.<\/p>\n\n\n\n<p>La partie m\u00e9di\u00e9vale, domin\u00e9e par son imposant donjon et ses fortifications, rappelle le r\u00f4le d\u00e9fensif du ch\u00e2teau aux fronti\u00e8res de la Bretagne. Construite principalement en schistes locaux, cette forteresse massive est caract\u00e9ristique de l\u2019architecture militaire du Moyen \u00c2ge, avec ses murailles \u00e9paisses, ses tours et ses douves.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"360\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_144811-1024x360.jpg\" alt=\"\" class=\"wp-image-506\" style=\"aspect-ratio:2.8445245019315073;width:1171px;height:auto\" srcset=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_144811-1024x360.jpg 1024w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_144811-300x106.jpg 300w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_144811-768x270.jpg 768w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_144811-1536x540.jpg 1536w, https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_144811-2048x721.jpg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p>Le ch\u00e2teau Renaissance, ajout\u00e9 plus tard, contraste fortement avec l\u2019aust\u00e9rit\u00e9 de la forteresse m\u00e9di\u00e9vale. Plus ouvert et plus lumineux, il m\u00eale briques rouges et pierres calcaires claires dans un style inspir\u00e9 de la Renaissance fran\u00e7aise, ainsi que de nombreuses colonnes de schistes. Nous avons notamment pu d\u00e9couvrir la c\u00e9l\u00e8bre Chambre dor\u00e9e, richement d\u00e9cor\u00e9e, qui t\u00e9moigne du raffinement recherch\u00e9 par la noblesse \u00e0 cette \u00e9poque. <\/p>\n\n\n\n<div id=\"wp-block-themeisle-blocks-slider-a9a56054\" class=\"wp-block-themeisle-blocks-slider glide\" data-per-view=\"1\" data-gap=\"0\" data-peek=\"0\" data-autoplay=\"true\" data-height=\"400px\" data-hide-arrows=\"false\"><div class=\"glide__track\" data-glide-el=\"track\"><div class=\"glide__slides\"><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_145853-1-scaled.jpg\" alt=\"\" title=\"\" data-id=\"520\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260524_124939647-scaled.jpg\" alt=\"\" title=\"\" data-id=\"517\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_144732-1-scaled.jpg\" alt=\"\" title=\"\" data-id=\"521\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_144734-scaled.jpg\" alt=\"\" title=\"\" data-id=\"519\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_143848-scaled.jpg\" alt=\"\" title=\"\" data-id=\"518\"\/><\/figure><\/div><\/div><div class=\"glide__bullets\" data-glide-el=\"controls[nav]\"><button class=\"glide__bullet\" data-glide-dir=\"=0\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=1\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=2\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=3\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=4\"><\/button><\/div><\/div><\/div>\n\n\n\n<p>Apr\u00e8s la visite du ch\u00e2teau, nous avons parcouru le centre historique de Ch\u00e2teaubriant. Plusieurs maisons \u00e0 colombages y sont encore visibles : leur structure en poutres de bois apparentes permettait autrefois de construire des habitations solides tout en \u00e9conomisant la pierre, plus co\u00fbteuse. Certaines anciennes devantures commerciales sculpt\u00e9es sont \u00e9galement conserv\u00e9es, avec leurs d\u00e9tails en bois travaill\u00e9s, t\u00e9moins de l\u2019activit\u00e9 artisanale et commer\u00e7ante de la ville aux si\u00e8cles pass\u00e9s.<\/p>\n\n\n\n<div id=\"wp-block-themeisle-blocks-slider-8caeb3f6\" class=\"wp-block-themeisle-blocks-slider glide\" data-per-view=\"1\" data-gap=\"0\" data-peek=\"0\" data-autoplay=\"true\" data-height=\"400px\" data-hide-arrows=\"false\"><div class=\"glide__track\" data-glide-el=\"track\"><div class=\"glide__slides\"><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_160441-scaled.jpg\" alt=\"\" title=\"\" data-id=\"524\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260524_140947975-scaled.jpg\" alt=\"\" title=\"\" data-id=\"526\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/20260524_160957-scaled.jpg\" alt=\"\" title=\"\" data-id=\"523\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/PXL_20260524_141948524-scaled.jpg\" alt=\"\" title=\"\" data-id=\"525\"\/><\/figure><\/div><\/div><div class=\"glide__bullets\" data-glide-el=\"controls[nav]\"><button class=\"glide__bullet\" data-glide-dir=\"=0\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=1\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=2\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=3\"><\/button><\/div><\/div><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Le mus\u00e9e des min\u00e9raux de la Ferme de l\u2019Orme<\/h3>\n\n\n\n<p>Pour terminer ce s\u00e9jour, nous avons visit\u00e9 le mus\u00e9e des min\u00e9raux de la Ferme de l\u2019Orme, consacr\u00e9 aux min\u00e9raux fran\u00e7ais. Le mus\u00e9e pr\u00e9sente de nombreuses esp\u00e8ces min\u00e9rales provenant des diff\u00e9rentes r\u00e9gions fran\u00e7aises, permettant de mieux comprendre la richesse g\u00e9ologique du territoire. Ses nombreuses vitrines class\u00e9es par composition chimique montrent des pi\u00e8ces d&rsquo;exceptions.<\/p>\n\n\n\n<div id=\"wp-block-themeisle-blocks-slider-2df66769\" class=\"wp-block-themeisle-blocks-slider glide\" data-per-view=\"1\" data-gap=\"0\" data-peek=\"0\" data-autoplay=\"true\" data-height=\"400px\" data-hide-arrows=\"false\"><div class=\"glide__track\" data-glide-el=\"track\"><div class=\"glide__slides\"><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/625376438_1430770445504454_8454440654900978082_n.jpg\" alt=\"\" title=\"\" data-id=\"537\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/530248848_1285429093371924_4302678382333615995_n.jpg\" alt=\"\" title=\"\" data-id=\"538\"\/><\/figure><\/div><div class=\"wp-block-themeisle-blocks-slider-item-wrapper glide__slide\" tabindex=\"0\"><figure><img decoding=\"async\" class=\"wp-block-themeisle-blocks-slider-item\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/626010453_1430770478837784_2043732042344120198_n.jpg\" alt=\"\" title=\"\" data-id=\"536\"\/><\/figure><\/div><\/div><div class=\"glide__bullets\" data-glide-el=\"controls[nav]\"><button class=\"glide__bullet\" data-glide-dir=\"=0\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=1\"><\/button><button class=\"glide__bullet\" data-glide-dir=\"=2\"><\/button><\/div><\/div><\/div>\n\n\n\n<p>Page Facebook du mus\u00e9e : <\/p>\n\n\n\n<a href=\"https:\/\/www.facebook.com\/p\/La-ferme-de-lOrme-Mus%C3%A9e-mines-et-min%C3%A9raux-100057145371218\/?locale=fr_FR\" \n   target=\"_blank\" \n   rel=\"noopener noreferrer\">\n    <img decoding=\"async\" src=\"https:\/\/ssnhs17.fr\/wp-content\/uploads\/2026\/05\/MuseeMinerauxFermeOrme.jpg\"\n         alt=\"Page Facebook du mus\u00e9e des min\u00e9raux de la Ferme de l\u2019Orme\"\n         style=\"max-width:50%; height:auto; border:1px solid #ccc; border-radius:8px;\">\n<\/a>\n\n\n\n<p>Ce s\u00e9jour nous a permis de traverser plusieurs centaines de millions d\u2019ann\u00e9es d\u2019histoire g\u00e9ologique, depuis les oc\u00e9ans ordoviciens jusqu\u2019\u00e0 la formation de la cha\u00eene hercynienne, tout en d\u00e9couvrant un riche patrimoine historique et minier.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u00c0 l\u2019occasion du week-end de Pentec\u00f4te, nous avons pass\u00e9 quatre jours \u00e0 d\u00e9couvrir une partie du socle hercynien du sud de la Bretagne historique, entre le sud de Nantes et la r\u00e9gion de Rennes. Ce voyage m\u00ealait g\u00e9ologie, patrimoine minier et histoire m\u00e9di\u00e9vale, avec plusieurs \u00e9tapes marquantes. \u00c0 la recherche des \u00e9clogites \u00e0 Saint-Philbert-de-Bouaine Notre [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":529,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_themeisle_gutenberg_block_has_review":false,"footnotes":""},"categories":[6],"tags":[],"class_list":["post-504","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-geologie"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=\/wp\/v2\/posts\/504","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=504"}],"version-history":[{"count":6,"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=\/wp\/v2\/posts\/504\/revisions"}],"predecessor-version":[{"id":539,"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=\/wp\/v2\/posts\/504\/revisions\/539"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=\/wp\/v2\/media\/529"}],"wp:attachment":[{"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=504"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=504"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ssnhs17.fr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=504"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}