Re-discussion on the detrital zircon provenance of the lower Yanchang Formation in the southern Ordos Basin

Open Geosciences

Zhang Yu¹  Zhang Haidong²  Liu Jianchao²  Chen Yangyang² 

[1] School of Marine Sciences, Guangxi University, Nanning 530004, China;The School of Earth Science and Resources, Chang’an University, Xi’an, 710054, China;

关键词: triassic;    ordos basin;    detrital zircon;    provenance;   

DOI  :  10.1515/geo-2016-0037

来源: DOAJ

【 摘 要 】

The Ordos Basin is the second largest sedimentary basin in China. The Yanchang Formation is the key oilbearing layer in the Ordos Basin. The stratigraphic time interval and the stratigraphic division of the Yanchang Formation has been highly debated with estimates ranging from Middle Triassic to Late Triassic. According to the latest studies on the stratigraphical division of Yanchang Formation, it was considered to be deposited as early as the Middle Triassic. Based on this new understanding, we reexamined the previous studies of the detrital zircons from the lower Yanchang Formation. The detrital zircons from the lower Yanchang Formation were divided into three groups based on their U-Pb ages: Paleozoic, Paleoproterozoic, and Neoarchean. The lack of Neoproterozoic U-Pb ages indicates no input from either the Qinling Orogen or the Qilian Orogen. The two older age groups (Paleoproterozoic, and Neoarchean) are likely derived from the North China Craton basement. The Paleozoic zircons were derived from the Inner Mongolia Paleo-uplift. The lower Yanchang Formation was mainly derived from the Inner Mongolia Paleo-uplift instead of being recycled from the previous sedimentary material from the central-eastern North China Craton as was previously hypothesized.

【 授权许可】

Unknown