{
  "abstract": "Understanding the origin and evolution of Variscan ophiolitic sequences is crucial for reconstructing the palaeogeography of the Variscan belt. The Chamrousse ophiolite (External Crystalline Massif, Western Alps) dated by U -Pb zircon presents a Late Devonian-Early Mississippian age (355-345 Ma), which coincides with the beginning of the Palaeotethysian Cycle. By characterising the melt source of this ophiolite through new zircon chemical investigations, we propose a geodynamic opening model in a pull-apart setting during the Palaeotethysian break-up. Through low U/Yb, Nb/Yb and Th/Yb ratios coupled with highly radiogenic initial Hf isotopes (ca. +12), the Chamrousse ophiolite demonstrates an oceanic origin from a chemically depleted mantle source. Its architecture illustrates the structure of magma-poor oceanic ridges and rifted margins suggesting that the Chamrousse ocean basin opened likely in a transtensional pull-apart setting. This oceanic basin is preserved between its two conjugate margins. To the west, the bimodal Séchilienne unit reflects the Cambro-Ordovician continental rifting of the North-Gondwana margin. To the east, the Late Devonian-Early Mississippian Rioupéroux-Livet-Gavet formation is made of a bimodal magmatic and volcanosedimentary association. The Rioupéroux meta-trondhjemite (ca. 367 Ma) could record the earliest stage of rifting, that may have led to the continental break-up and the Chamrousse opening. This geodynamic scenario can be integrated into the broader triangular Palaeotethysian break-up, where the Chamrousse marginal oceanic basin and other extensional volcano-sedimentary continental basins located in the Moroccan Meseta and Bohemian Massif, are triggered by the westward propagation of the Palaeotethys Ocean, prior to the final assembly of Pangea.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "name": "Maureen Gunia"
    },
    {
      "name": "Adrien Vezinet"
    },
    {
      "name": "Carole Cordier"
    },
    {
      "name": "Emilie Janots"
    },
    {
      "name": "Anna Duhoux"
    },
    {
      "name": "Stéphane Guillot"
    },
    {
      "name": "Alexis Plunder"
    },
    {
      "name": "Alexander V Sobolev"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/9af2ck26fhkkm.bib",
  "cited_by": 0,
  "doi": "10.1016/j.lithos.2026.108749",
  "fulltext_url": null,
  "id": "9af2ck26fhkkm",
  "issns": [
    "0024-4937",
    "1872-6143"
  ],
  "landing_url": "https://brgm.hal.science/hal-05734026v1",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "hal",
      "0.sdu"
    ],
    [
      "hal",
      "1.sdu.stu"
    ],
    [
      "openalex",
      "1908|Geological and Geochemical Analysis"
    ]
  ],
  "openalex": "W7204046895",
  "pdf_url": "https://brgm.hal.science/hal-05734026/document",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-01",
  "publisher": "Elsevier",
  "ris": "https://research.draconitic.com/paper/9af2ck26fhkkm.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:24Z",
      "native_id": "hal-05734026",
      "source": "hal",
      "url": "https://brgm.hal.science/hal-05734026v1"
    }
  ],
  "subjects": [
    {
      "field": "earth",
      "origin": "openalex:1908|Geological and Geochemical Analysis",
      "subfield": "geophysics"
    }
  ],
  "title": "A remnant of the Palaeotethys break-up: The Variscan Chamrousse ophiolite (Western Alps)",
  "title_text": "A remnant of the Palaeotethys break-up: The Variscan Chamrousse ophiolite (Western Alps)",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:24Z",
  "url": "https://research.draconitic.com/paper/9af2ck26fhkkm",
  "venue": "Lithos",
  "versions": []
}