DETRITAL ZIRCON CHARACTERISTICS OF THE MESOPROTEROZOIC SERIES IN TAIHANG AND XIONG’ER MOUNTAIN: IMPLICATIONS FOR BASIN EVOLUTION IN THE CENTRAL AND SOUTHERN NORTH CHINA CRATON

The breakup of the Proterozoic supercontinent Columbia lead to the formation of the Mesoproterozoic sedimentary basins worldwide. The central NCC deposited the Changcheng, Jixian and Qingbaikou groups, which were well documented in previous literatures and got huge progresses in geochronology recently. The Mesoproterozoic in the south of the NCC mainly distributed in three areas, including the Wufoshan Group in Songshan area, the Ruyang and Luoyu groups in the Xiong’er Mountain and the Gaoshanhe Group in the North Qinling area. There are still controversies on the time of the initial deposition, the geochronological framework as well as the mechanisms driving the formation of the basins.

In this contribution, we conducted detrital zircon U-Pb isotope dating of the samples from the Changcheng Group in the central NCC. Together with the previous geochronological dataset and the vertical lithological associations from the southern NCC, we aimed to discuss the relationship between the basins in the central and south and shed some lights on the tectonic evolution of the Mesoproterozoic basins in the NCC.

Our samples were from the Chuanlinggou and Zhaojiazhuang formations of the Changcheng Group in the central of the NCC, the Yunmengshan and Baicaoping formations of the Ruyang Group in the southern NCC. Our data showed the distinct similarity of the detrital zircon age distribution between the Chuanlinggou Formation and the Zhaojiazhuang Formation in the central NCC. On the contrary, the differences of the detrital zircon age pattern from the Mesoproterozoic series between the central and southern NCC were distinct.

We suggest the differences of the detrital zircon pattern of different formations from different areas can reflect the evolution of the Mesoproterozoic basins in the NCC. It indicated that the rift of the NCC were possibly initial from the south and deposited the Bingmagou Formation and the Yunmengshan Formation simultaneously, then progressively developed further to the north. During the deposition of the Baicaoping Formation, the southern NCC possessed a relative deep-water environment and deposited the fine-grain silicilastics rocks. Meanwhile, in the areas further north, the rifting just began and deposited the Zhaojiazhuang Formation with coarse siliciclasitics lithology.