New age data for the Baoban Complex, South China establishes that it lay outboard of western Laurentia in the early Mesoproterozoic but was not part of the Cathaysia Block, with which it is traditional linked, until the mid-Paleozoic. Our geochronology data for detrital zircon and authigenic monazite grains from metasedimentary rocks indicate accumulation between ca. 1.55 Ga and 1.45 Ga for the Gezhencun succession of the Baoban Complex and ca. 1.45 Ga and 1.30 Ga for the Ewenling succession. The former unit is dominated by detrital zircon populations between 1900 Ma and 1500 Ma with two peaks at 1780 Ma and 1580 Ma. The Ewenling succession has detrital zircon peaks at 1720 Ma and 1450 Ma. Newly discovered gneissic granites were emplaced at 1550 Ma and intruded by 1450 Ma leucogranite dykes that are coeval with 1460–1430 Ma bimodal magmatism. The whole Baoban Complex was metamorphosed over the range of 1.3–0.9 Ga based on ages of authigenic zircon and monazite.Depositional ages of metasedimentary rocks are coeval with successions of the Belt-Purcell Basin, western Laurentia. Detrital zircon from the two regions have similar age populations and Lu-Hf compositions, and display a synchronous provenance shift at ca. 1.45 Ga. Basement lithologies on Hainan Island range in age from ca. 1.55–1.43 Ga and underwent metamorphism during 1.3–0.9 Ga. This is younger than basement rocks on the mainland of the Cathaysia Block in South China, suggesting the two regions are spatially unrelated at this time and hence the Mesoproterozoic record of the island cannot constrain the location of the Cathaysia Block in the Nuna and Rodinia supercontinents.

中文翻译：

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华南中元古代的宝板综合体：西部Laurentian岩石圈的缺失片段

华南宝板综合体的新纪元数据表明，它位于中元古生代早期的劳伦西亚西部外围，但直到古生代中期才与它有传统联系的华夏地块。我们从准沉积岩中碎屑锆石和自生独居石颗粒的地质年代学数据表明，大约在两个沉积岩之间形成了堆积。宝板复杂葛镇村演替的1.55 Ga和1.45 Ga。Ewenling序列为1.45 Ga和1.30 Ga。前者以1900 Ma至1500 Ma之间的碎屑锆石为主，其中两个峰值分别为1780 Ma和1580 Ma。Ewenling演替在1720 Ma和1450 Ma处有碎屑锆石峰。新发现的片麻岩花岗岩置于1550 Ma，并由1450 Ma的白云石岩岩侵入，这些岩岩与1460–1430 Ma的双峰岩浆作用同时存在。根据自生锆石和独居石的年龄，整个宝板复合体在1.3–0.9 Ga范围内发生了变质。变质沉积岩的沉积年龄与西劳伦提亚的贝尔特－珀塞尔盆地的演替相吻合。来自这两个地区的碎屑锆石具有相似的年龄种群和Lu-Hf组成，并且在ca处显示出同步的物源偏移。海南岛1.45 Ga。地下岩性的年龄范围大约为大约 1.55–1.43 Ga，并在1.3–0.9 Ga内经历了变质作用。这比华南华夏地块大陆上的基底岩石还年轻，这表明这两个区域目前在空间上没有关联，因此该岛的中元古代记录不能约束华纳街区在努纳和罗迪尼亚超大陆的位置。