Provenance of the Paleogene sediments in the Pearl River Mouth Basin, northern South China Sea: Insights from zircon U-Pb and fission track double dating

• Published in: Journal of Asian earth sciences 2020-09, Vol.200, p.104494, Article 104494
• Main Authors: Tang, Xiaoyin, Yang, Shuchun, Hu, Shengbiao
• Format: Article
• Language: English
• Subjects: Paleogene; Pearl River Mouth Basin; Provenance; Zircon fission track; Zircon U-Pb
• ISSN: 1367-9120; 1878-5786
• DOI: 10.1016/j.jseaes.2020.104494

[Display omitted] •First zircon U-Pb & FT double-dating dataset for Paleogene sediments were presented.•Sediments were dominantly derived from the intra-basinal uplifts before Late Eocene.•Southeastern Cathaysia Block was the main sediment provenance since Late Eocene.•There was no significant provenance shift during the Oligocene period. The Paleogene provenance of the Pearl River Mouth Basin in the northern South China Sea is poorly understood. In this paper, we present the first batch of zircon U-Pb and fission track double-dating ages of the Wenchang, Enping, and Zhuhai Formations in this basin. Together with data from previous provenance studies, the new dataset has been used to document the provenance shift during the Paleogene period. Characterized by a rather limited spectrum of both U-Pb and fission-track ages, the Eocene Wenchang Formation was probably mainly derived from intra-basinal uplifts. Multimodal distribution and large range of zircon ages of the Late Eocene-Early Oligocene Enping Formation is compatible with the age signatures of modern drainage sediments from the Southeastern Cathaysia Block. Age signatures of the Zhuhai Formation (Late Oligocene) and Enping Formation are indistinguishable, suggesting that they may have similar source areas and sediment provenance did not change dramatically during the Oligocene. Although variations in age patterns from the Wenchang Formation to the Enping-Zhuhai Formations imply a dominant provenance shift from local uplifts to the regional Cathaysia Block, it is difficult to exclude the influence of the local uplifts on sediments in the Enping-Zhuhai Formations.