Abstract
Abstract Palaeogene environmental evolution in East Asia remains ambiguous. Here we present integrative work including magnetostratigraphy, grain-size, geochemistry, and clay mineralalogy from a 1609-m-thick fluviolacustrine sequence in eastern China. The results reveal two periods of tectonic control alternating with three periods of climatic control on the sedimentary evolution. Tectonic activity in the study area, as revealed by particle coarsening and reduced weathering, occurred during 65.6-59 Ma and strengthened in Asia during 55-54 Ma in response to the India-Eurasia collision. Weathering gradually enhanced in East Asia during 59-55 Ma, probably caused by global warming. Continuous global warming during 54-50.5 Ma is responsible for enhanced aridification in East Asia. From 50.5 to 37.6 Ma, global cooling weakened evapotranspiration and increased westerlies-derived moisture. Both aspects increased effective moisture and chemical weathering in East Asia. These results shed light on how alternating tectonism and climate change impacted environmental evolution in Asia during the Palaeogene.
Original language | English |
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Article number | e2021GL096832 |
Number of pages | 11 |
Journal | Geophysical Research Letters |
Volume | 49 |
Issue number | 3 |
Early online date | 24 Jan 2022 |
DOIs | |
Publication status | Published - 16 Feb 2022 |
Bibliographical note
AcknowledgmentsThis work is financially supported by the National Natural Science Foundation of
China (41572346) and National Nonprofit Fundamental Research Grant of China,
Institute of Geology, China Earthquake Administration (IGCEA1906). We feel
grateful to Prof. Jin Meng, Prof. Peter D. Clift, and Dr. Jessica A. Thompson Jobe
for the valuable comments and constructive suggestions. We thank Dr. Zuolin
Chen and Ms Xue Mao for assistance in the field, and Ms Yanhao Li and Mr
Youliang Bai for help in the laboratory. We appreciate Prof. Lucy Flesch (editor)
for handling our manuscript and two anonymous reviewers for constructive reviews
Keywords
- Fluviolacustrine sediments
- Palaeogene
- East Asia
- Environmental evolution
- Tectonism
- Climate change