摘要
A comparative analysis of the geochemical characteristics of sediments from the Oligocene Zhuhai Formation(32-23.8 Ma),the Miocene Zhujiang Formation(23.8-16.5 Ma),and the Hanjiang Formation(16.5—10.5 Ma) and a comprehensive analysis of the geochemical characteristics of rocks surrounding the paleo-Pearl River drainage contribute to understanding the influences of the Tibetan Plateau uplift on provenance evolution of the paleo-Pearl River.The results show that the geochemical characteristics of sediments from the Oligocene Zhuhai Formation are very different from the geochemical characteristics of sediments from the Miocene Zhujiang and Hanjiang Formations.The ∑ rare earth elements(REE) of mudstone is relatively high in the Zhuhai Formation,204.07-293.88 ppm(average 240.46 ppm),and low in the Zhujiang and Hanjiang Formations,181.32-236.73 ppm(average 203.83 ppm) and 166.84-236.65 ppm(average199.04 ppm),respectively.The chemical index of alteration(CIA) for these samples has a similar trend to the∑ REE:the CIA of the Zhuhai Formation is relatively high and the CIA of the Zhujiang and Hanjiang Formations is relatively low.The uplift of the Tibetan Plateau is crucial to the westward expansion of the paleo-Pearl River drainage.
A comparative analysis of the geochemical characteristics of sediments from the Oligocene Zhuhai Formation（32-23.8 Ma）,the Miocene Zhujiang Formation（23.8-16.5 Ma）,and the Hanjiang Formation（16.5—10.5 Ma） and a comprehensive analysis of the geochemical characteristics of rocks surrounding the paleo-Pearl River drainage contribute to understanding the influences of the Tibetan Plateau uplift on provenance evolution of the paleo-Pearl River.The results show that the geochemical characteristics of sediments from the Oligocene Zhuhai Formation are very different from the geochemical characteristics of sediments from the Miocene Zhujiang and Hanjiang Formations.The ∑ rare earth elements（REE） of mudstone is relatively high in the Zhuhai Formation,204.07-293.88 ppm（average 240.46 ppm）,and low in the Zhujiang and Hanjiang Formations,181.32-236.73 ppm（average 203.83 ppm） and 166.84-236.65 ppm（average199.04 ppm）,respectively.The chemical index of alteration（CIA） for these samples has a similar trend to the∑ REE：the CIA of the Zhuhai Formation is relatively high and the CIA of the Zhujiang and Hanjiang Formations is relatively low.The uplift of the Tibetan Plateau is crucial to the westward expansion of the paleo-Pearl River drainage.
基金
supported by the National Major Scientific and Technological Special Project during the Twelfth Fiveyear Plan Period(Grant No.2011ZX05023-002)
