Evaluation of Cretaceous Hinterland Weathering and Climate in the Sichuan Basin, SW China
- 1 Graduate School of Creative Science and Engineering, Waseda University, Tokyo, Japan
- 2 Graduate School of Creative Science and Engineering, Waseda University, Tokyo, Japan
- 3 Faculty of Education and Integrated Arts and Sciences, Waseda University, Tokyo, Japan
- 4 State Key Laboratory of Palaeobiology and Stratgraphy, Center for Excellence in Life and Environment, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Science, Nanjing, China
Abstract
Cretaceous is characterized by high atmospheric CO2 concentration and a resultantly high temperature. Thus, the Earth system, which operated during the greenhouse condition, can be deduced by the investigation of the paleoclimate during the Cretaceous. However, information of paleoclimate from continental inland-basins is scarce compared to that from continental margin marine-basins. In this research, the changes of weathering condition through the whole Cretaceous Period were reconstructed by analyzing the whole-rock chemical composition and clay mineral composition of mudstone samples collected in the Sichuan Basin, SW China. The reconstructed paleoweathering intensity positively correlates with paleotemperature estimate, indicating that Cenomanian-Turonian stages were climatic optimum in the Sichuan Basin as well. Furthermore, the result suggests a Cenomanian-Turonian extremely high amplitude humidity fluctuation.
- Hasegawa, H., Tada, R., Jiang, X., Suganuma, Y., Imsamut, S., Charusiri, P., Ichinnorov, N. and Khand, Y. (2012) Drastic Shrinking of the Hadley Circulation during the Mid-Cretaceous Supergreenhouse. Climate of the Past, 8, 1323-1337. https://doi.org/10.5194/cp-8-1323-2012
- Li, Y., Li, C., He, D., Chen, L., Mei, Q. and Zhang, L. (2016) Cretaceous Sedimentary Basins in Sichuan, SW China: Restoration of Tectonic and Depositional Environments. Cretaceous Research, 57, 50-65. https://doi.org/10.1016/j.cretres.2015.07.013
- Ohta, T. and Arai, H. (2007) Statistical Empirical Index of Chemical Weathering in Igneous Rocks: A New Tool for Evaluating the Degree of Weathering. Chemical Geology, 240, 280-297. https://doi.org/10.1016/j.chemgeo.2007.02.017
- O’Brien, C.L., Robinson, S.A., Pancost, R.D., Sinninghe Damsté, J.S., Schouten, S., Lunt, D.J., Alsenz, H., Bornemann, A., Bottini, C., Brassell, S.C., Farnsworth, A., Forster, A., Huber, B.T., Inglis, G.N., Jenkyns, H.C., Linnert, C., Littler, K., Markwick, P., McAnena, A., Mutterlose, J., Naafs, B.D.A., Püttmann, W., Sluijs, A., van Helmond, N.A.G.M., Vellekoop, J., Wagner, T. and Wrobel, N.E. (2017) Cretaceous Sea-Surface Temperature Evolution: Constraints from TEX86 and Planktonic Foraminiferal Oxygen Isotopes. Earth-Science Reviews, 172, 224-247. https://doi.org/10.1016/j.earscirev.2017.07.012