Calibrating the Jehol Biota in the Baiwan Basin of the North Qinling Orogenic Belt, central China

The Jehol Biota sensu lato has a very wide distribution in East Asia, providing palaeontological clues for recovering the Early Cretaceous terrestrial ecosystems. This Biota was considered to reach the Qinling Orogenic Belt but its reaching time remains unclear. In this study, we initially constrained the age of the Jehol Biota recovered from the Baiwan Formation of the Baiwan Basin, Zhenping County, southwestern Henan Province, which geographically lies in the North Qinling Orogenic Belt. LA-ICP-MS U-Pb analyses were conducted for the fossil-bearing layers, providing a maximum depositional age of ca. 123.6 Ma (early Aptian). This age is consistent with the biostratigraphic analyses, and can approximately constrain the fossil-bearing layers. This study confirmed that the Jehol Biota has already reached the Qinling Orogenic Belt during its secondary evolutionary stage, revealing the unique palaeogeographic position of this belt for the dispersal of the Jehol Biota in East Asia. (c) 2024 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.