Zircon U-Pb geochronology of Baoyintu beds in the northwestern margin of the North China Craton
Ding, Chengwu (2021), Zircon U-Pb geochronology of Baoyintu beds in the northwestern margin of the North China Craton, Dryad, Dataset, https://doi.org/10.5061/dryad.jh9w0vtb5
The Baoyintu Inlier is located at the northwestern margin of the North China Craton (NCC). Here we present LA-ICP-MS and SHRIMP U-Pb data for zircons extracted from samples of monzogranitic orthogneiss and units in the beds. The 1679±13 Ma date for the orthogneiss demonstrates that Late Palaeoproterozoic rocks do exist in the inlier. The ca. 1413 Ma minimum age of detrital zircons in metasedimentary rocks shows that the maximum age of the Baoyintu beds is Mesoproterozoic. The age distribution of detrital zircons in the structurally lowest exposed part of the beds form clusters at ca. 2680, 2450, 1800 and 1560 Ma, which partly correspond to tectonic-magmatic–metamorphic events previously recognised in the NCC. A structurally higher unit in the beds yields age peaks at ca. 1640 and 1500 Ma limiting the maximum age of the beds at ca. 1500 Ma. Amphibolite with a dolerite protolith from the upper unit also shows evidence for metamorphism during ca. 877-851 Ma.