{"id":6979,"date":"2021-01-07T15:33:27","date_gmt":"2021-01-07T14:33:27","guid":{"rendered":"https:\/\/www.geoparc-chablais.com\/?page_id=6979"},"modified":"2021-07-07T15:46:51","modified_gmt":"2021-07-07T13:46:51","slug":"geological-description","status":"publish","type":"page","link":"https:\/\/www.geoparc-chablais.com\/en\/science-and-research\/geological-description\/","title":{"rendered":"Geological Description"},"content":{"rendered":"

In the 50 km separating Thonon-les-Bains from Joux Plane pass (Morzine-Les Gets), the Chablais’ rocks reveal the history of the Alps’ formation. The Dranse de Morzine valley is a natural geological section, from the pillow lava in Les Gets (a vestige of the ancient Alpine Ocean) to Lake Geneva, which was created by the Rh\u00f4ne glacier. In this exceptional area, 245 million years of history are told.<\/p>\n<\/div><\/div>\n\n

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A simplified geological history of the Chablais <\/h2>\n<\/div>\n\n

The formation of the Chablais’ landscape began nearly 245 million years ago (mya). It can be broken down into 3 main acts: the formation of rocks, the formation of reliefs, and the shaping of landscapes by humans and erosion.<\/p>\n\n

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Act 1: the formation of rocks<\/h3>\n<\/div>\n\n

Nearly 245 mya, at the beginning of the Mesozoic era, the Earth looked very different than it does today. The supercontinent Pangaea fragmented and a body of water \u2014 the Tethys Sea \u2014 emerged between what would become Europe and Africa.<\/p>\n\n\n

\"La
The Earth at the end of the Triassic (around 210 mya)
The red dot indicates the location of the Chablais rocks being formed during this period<\/figcaption><\/figure>\n\n\n
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During the Mesozoic era: the Triassic, Jurassic, and Cretaceous periods<\/h4>\n<\/div>\n\n
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During the entire Mesozoic era, the rocks in the Chablais Prealps were being formed in the Tethys Sea, which continued to expand. Even the two wide continental margins of Europe and Africa were underwater, without a single mountain on the horizon.<\/p>\n<\/div>\n\n\n

\"Etape
Act 1: The Chablais’ geological history began with the formation of its rocks in a mainly marine environment, through sediment deposits in various marine “basins”. In this diagram, the colours represent these different basins. The marine environments did not all have the same depth, biological activity, temperature, sediment supply, currents, etc.<\/figcaption><\/figure><\/div>\n\n\n