Provenance and Implication of Carboniferous–Permian Detrital Zircons from the Upper Paleozoic, Southern Ordos Basin, China: Evidence from U-Pb Geochronology and Hf Isotopes

Abstract

Carboniferous−Permian detrital zircons are recognized in the Upper Paleozoic of the whole Ordos Basin. Previous studies revealed that these Carboniferous−Permian zircons occurred in the Northern Ordos Basin mainly originated from the Yinshan Block. What has not been well documented until now is where this period’s zircons in the Southern Ordos Basin came from, and very little discussion about their provenance. To identify the provenance of the detrital zircons dating from ~350 to 260 Ma, five sandstone samples from the Shan 1 Member of Shanxi Formation and eight sandstone samples from the He 8 Member of Shihezi Formation were analyzed for detrital zircon U-Pb age dating and in situ Lu-Hf isotopic compositions. The results indicate that the two age clusters of 520−378 Ma and ~350−260 Ma in the Southern Ordos Basin most likely derived from the North Qinling Orogenic Belt−North Qilian Orogenic Belt and the North Qinling Orogenic Belt, respectively. Furthermore, we propose that the zircons aging ~320−260 Ma are representative of the important tectonothermal events occurred in the North Qinling Orogenic Belt during the Late Paleozoic.

Keywords

• provenance
• detrital zircon
• la–icp–ms
• u-pb dating
• lu-hf isotope
• upper paleozoic
• ordos basin