Song Zehua, Wan Shiming, Colin Christophe, France-Lanord Christian, Yu Zhaojie, Dapoigny Arnaud, Jin Hualong, Li Mengjun, Zhang Jin, Zhao Debo, Shi Xuefa, Li Anchun
Key Laboratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Université Paris-Saclay, Centre National de la Recherche Scientifique (CNRS), Géosciences Paris-Saclay (GEOPS), Orsay 91405, France.
Key Laboratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266061, China; Center for Excellence in Quaternary Science and Global Change, Chinese Academy of Sciences, Xi'an 710061, China.
Sci Bull (Beijing). 2023 Feb 15;68(3):305-313. doi: 10.1016/j.scib.2023.01.015. Epub 2023 Jan 13.
Enhanced silicate weathering induced by the uplift of the Himalayan-Tibetan Plateau (HTP) has been considered as the major cause of pCO decline and Cenozoic cooling. However, this hypothesis remains to be validated, largely due to the lack of a reliable reconstruction of the HTP weathering flux. Here, we present a 37-million-year record of the difference in the seawater radiogenic neodymium isotopic composition (Δε) of Ocean Drilling Program (ODP) sites and Fe-Mn crusts between the northern and central Indian Ocean, which indicates the contribution of regional weathering input from the South Asian continent to the Indian Ocean. The results show a long-term increase in Δε and thus provide the first critical evidence of enhanced South Asian weathering input since the late Eocene. The evolution coincided well with major pulses of surface uplift in the HTP and global climatic transitions. Our foraminiferal ε record suggests that tectonic uplift and silicate weathering in South Asia, especially in the Himalayas, might have played a significant role in the late Cenozoic cooling.
喜马拉雅-青藏高原（HTP）隆升引发的增强型硅酸盐风化作用，被认为是pCO下降和新生代变冷的主要原因。然而，这一假说仍有待验证，主要是因为缺乏对HTP风化通量的可靠重建。在此，我们展示了一个长达3700万年的记录，该记录反映了印度洋北部和中部海洋钻探计划（ODP）站点以及铁锰结壳的海水放射性钕同位素组成差异（Δε），这表明了南亚大陆区域风化输入对印度洋的贡献。结果显示Δε呈长期上升趋势，从而提供了始新世晚期以来南亚风化输入增强的首个关键证据。这一演变与HTP地表隆升的主要脉冲以及全球气候转变高度吻合。我们的有孔虫ε记录表明，南亚尤其是喜马拉雅地区的构造隆升和硅酸盐风化作用，可能在新生代晚期变冷过程中发挥了重要作用。
