Detrital zircon U‐Pb dating and Hf isotope analysis have been evidenced to be effective for reconstructing paleography and tectonic evolution of different continental blocks/terranes. Our new detrital zircon U‐Pb and Hf isotopic results combined with literature data for the Paleozoic (meta)sedimentary rocks in the Baoshan and Lincang Blocks provide crucial constraints on the paleogeographic position and tectonic affinity of these blocks during Paleozoic times. The Lincang and Baoshan Blocks were linked with each other during Early Paleozoic times, located on the northern margins of Australia and India in Gondwana, respectively. But a rift‐related ocean basin could likely have existed between these two blocks although they were still attached to East Gondwana during Middle Devonian‐Early Permian times. In contrast, the Simao‐Indochina Block had rifted from East Gondwana at least before the Late Ordovician as reflected by their young age cluster at ~450 Ma that is distinct from the characteristic Pan‐African event (600–520 Ma) in Gondwana. Therefore, the Lincang Block did not represent a continental arc of the Simao Block before the Early Permian, but rather it rifted from the northern margin of Australia Gondwana in the Early Permian and subsequently as an independent block drifted northward to the west side of the Simao Block. Taken together, we propose that the Changning‐Menglian Tethys Ocean was a long‐lived ocean developing successively at least from the Late Ordovician to the Permian and that the southern continuation of the Lincang Block is the Inthanon zone rather than the Sukhothai zone.

中文翻译：

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古生代云南西部宝山和临沧地块的构造演化与古沉积

碎屑锆石U-Pb年代测定和Hf同位素分析已被证明可有效地重建不同大陆块/地貌的地貌和构造演化。我们的新碎屑锆石U-Pb和Hf同位素结果与宝山和临沧地块中的古生代（元）沉积岩的文献资料相结合，对古生代时期这些区块的古地理位置和构造亲和力提供了至关重要的限制。临沧和宝山地块在古生代早期就相互联系在一起，分别位于澳大利亚和印度的冈瓦纳北部边缘。但是，尽管在中泥盆纪-早二叠纪时期，这两个区块之间仍存在与裂谷有关的海盆，尽管它们仍依附在东冈瓦纳。相反，思茅—印度支那地块至少在晚奥陶纪之前就从东冈瓦纳开始裂谷，这反映在它们年龄约在450 Ma上，这与冈瓦纳典型的泛非事件（600–520 Ma）不同。因此，临沧地块并不代表早二叠世之前的思茅地块的大陆弧，而是从早二叠世的澳大利亚冈瓦纳北缘裂谷而来，随后作为一个独立的地块北移至思茅的西侧块。综上所述，我们认为长宁—孟连特提斯海洋是长寿海洋，至少从奥陶纪晚期到二叠纪是连续发展的，而临沧地块的南部延续是印度尼通地区而不是素可泰地区。