Provenance Analysis of the Paleogene Strata in the Northern Qaidam Basin, China: Evidences from Sediment Distribution, Heavy Mineral Assemblages and Detrital Zircon U–Pb Geochronology

Minerals

Jianguo Yin¹  Shuai Zhang²  Zhixiong Wu³ 

[1] Key Laboratory of Petroleum Resources, Gansu Province/Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China;Oil and Gas Survey, China Geological Survey, Beijing 100083, China;Research Institute of Exploration and Development, PetroChina Qinghai Oilfield Company, Dunhuang 736202, China;

关键词: provenance analysis;    stratigraphic thicknesses;    net sand to gross thickness ratio;    conglomerate percentage;    heavy mineral analysis;    detrital zircon U‒Pb geochronology;   

DOI  :  10.3390/min10100854

来源: DOAJ

【 摘 要 】

Using provenance analysis to build an accurate source-to-sink relationship is the key to infer mountain building scenarios around the Qaidam Basin, and also important to understanding the uplift and expansion of the Tibetan Plateau. However, some conflicting provenance inferences are caused by different interpretations for the prevalent existence of the late Paleozoic to early Mesozoic age group in detrital zircon U‒Pb age spectra of the Paleogene strata at the northern Qaidam Basin, and these need to be resolved. In this article, an integrated study of sediment distribution, heavy mineral assemblages, and detrital zircon U‒Pb geochronology is carried out to analyze provenance of the Paleogene strata at the northern Qaidam Basin. The decreasing trends of the net sand to gross thickness ratios and conglomerate percentages away from the Qilian Mountains and Altyn Tagh range to basin interior clearly support they are the provenance areas. Sedimentation of materials from the Altyn Tagh range is spatially confined to a small area in front of the mountains. A large sandy body with a uniform distribution of detrital zircon ages (containing a lot of the late Paleozoic to early Mesozoic zircon ages) and heavy mineral assemblages in the Xiaganchaigou Formation is supplied by the Qilian Mountains.

【 授权许可】

Unknown