Abstract Mid-oceanic shallow water carbonate platforms are usually characterized by long-term deposition due to the continuous subsidence of the underlying volcanic edifices and thus provide good records of biotic evolution and environmental changes. However, since most of the pre-Jurassic oceanic crust has been subducted, very few remains of Triassic atoll-like platforms are preserved in the Circum-Pacific region. Therefore, it is crucial to precisely document these Triassic carbonate occurrences to better understand the global evolution of climates and ecosystems during the Early Mesozoic in the huge Panthalassa Ocean. In the Sambosan Accretionary Complex (Southwest Japan), several Upper Triassic shallow water limestone blocks are especially well exposed at Mount Sambosan in Shikoku Island. Microfacies analyses associated with biostratigraphic data (reef assemblages, foraminifer associations and conodonts) allow us to reconstruct the geological history of these seamount fragments from the first settlement of reef biota in the Ladinian-Early Carnian to platform growth during the Late Carnian to Rhaetian. Finally, the demise of the carbonate platform occurred during the Latest Triassic to Early Jurassic, followed by platform collapse and accretion to the East Asia margin in the Late Jurassic-Early Cretaceous. Furthermore, cathodoluminescence microscopy reveals that the Sambosan limestone experienced several diagenetic episodes including early cementation, dissolution and dolomitization. At the global scale, the comprehensive sedimentary record at Mount Sambosan shows that evolution of shallow water ecosystems in the Panthalassa Ocean is consistent with biotic and environmental changes documented in coeval carbonate platforms from the Tethys Ocean.

中文翻译：

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Panthalassa洋海山的诞生和死亡：日本西南部四国三宝山的晚三叠世至早侏罗世沉积记录

摘要 中大洋浅水碳酸盐岩台地由于下伏火山结构的不断下沉，通常具有长期沉积特征，为生物演化和环境变化提供了良好的记录。然而，由于大部分侏罗纪前大洋地壳已经俯冲，环太平洋地区三叠纪类环礁台地遗迹很少。因此，精确记录这些三叠纪碳酸盐岩事件对于更好地了解巨大的泛大洋中早中生代气候和生态系统的全球演变至关重要。在三宝山增生杂岩（日本西南部）中，四国岛三宝山的几个上三叠统浅水石灰岩块体特别出露。与生物地层数据（珊瑚礁组合、有孔虫协会和牙形石）相关的微相分析使我们能够重建这些海山碎片的地质历史，从拉迪阶-卡尼阶早期的珊瑚礁生物群的第一次定居到卡尼阶晚期至雷蒂阶的地台生长。最后，碳酸盐台地的消亡发生在晚三叠世至早侏罗世，随后在晚侏罗世-早白垩世地台坍塌并增生到东亚边缘。此外，阴极发光显微镜显示 Sambosan 石灰岩经历了几次成岩作用，包括早期胶结、溶解和白云石化。在全球范围内，