NHESS Natural Hazards and Earth System Sciences NHESS Nat. Hazards Earth Syst. Sci. 1684-9981 Copernicus Publications Göttingen, Germany 10.5194/nhess-14-2069-2014 Palaeoclimate and palaeoseismic events discovered in Diexi barrier lake on the Minjiang River, China Wang X. Q. 1 Li Y. R. 2 3 Yuan Y. 1 Zhou Z. 1 Wang L. S. 1 State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Chengdu University of Technology), Chengdu 610059, China Taiyuan University of Technology, Taiyuan 030024, China AGECON Ltd., Hong Kong, China 14 08 2014 14 8 2069 2078 Copyright: © 2014 X. Q. Wang et al. 2014 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://nhess.copernicus.org/articles/14/2069/2014/nhess-14-2069-2014.html The full text article is available as a PDF file from https://nhess.copernicus.org/articles/14/2069/2014/nhess-14-2069-2014.pdf

Studies on the formation of the ancient Diexi barrier lake on the Mingjiang River, southwestern China, have long been carried out. However, investigations into the correlation between the palaeoclimate and palaeoenvironment and the palaeoseismic events in this area are rarely found in literature. The present study took sediments from the ancient Diexi barrier lake to investigate the palaeoclimate, palaeoenvironment and palaeoseismic events. A drilling at the centre of the barrier lake was conducted and the core of about 260 m long was examined. The palaeoclimate and palaeoenvironment indicators (sporopollen, carbon and oxygen isotopes, organic matter, calcium carbonate, granularity) from the sediments have been tested and analysed, and indicate that there were 10 climatic and environmental periods between 30 000 and 15 000 a BP (before present). The discovered disturbance segments in the core indicate there were at least 10 seismic events during that period. The consistency between climate change and seismic events indicates that a strong seismicity is normally accompanied by a climatic variation. This may be a useful supplement for climate and geohazard predictions in the future.

 References An, W., Zhao, J. Q., and Yan, X. B.: Tectonic deformation of lacustrine sediments in Qiangyang on the Minjiang fault zone and ancient earthquake, Seismol. Geol., 4, 980–988, 2008. Chen, J. A., Wan, G. J., and Tang, D. G.: Modern climate change Erhai Lake sediment grain size and isotopic records, Nat. Sci. Prog., 10, 253–259, 2000. Chen, J. A., Wan, G. J., and Zhang, F.: Environmental record in lake sediments at different time scales – a case study in sediment grain size, Chinese Sci. Ser. D, 33, 563–568, 2003. Duan, L. P.: The Ancient Barrier Lake and Geoenvironment, Diexi, Minjiang River, Ph.D. thesis, Chengdu University of Technology, China, 2002. Duan, L. P., Wang, L. S., and Yang, L. Z.: The ancient climatic evolution characteristic reflected by carbon and oxygen isotopes of carbonate in the ancient barrier lacustrine deposits, Diexi, Minjiang River, The Chinese J. Geol. Hazard Control, 13, 91–96, 2002. Krivonogov, S. K., Sheinkman, V. S., and Mistruykov, A. A.: Stages in the development of the Darhad dammed lake (Northern Mongolia) during the Late Pleistocene and Holocene, Quaternary Int., 136, 83–94, 2005. Moreiras, S. M.: Chronology of a probable geotectonic Pleistocene rock avalanche, Cordon del Plata (Central Andes), Mendoza, Argentina, Quaternary Int., 148, 138–148, 2006. Trauth, M. H. and Strecker, M. R.: Formation of landslide-dammed lakes during a wet period between 40,000 and 25,000 <abbr>yr</abbr> B. P. in northwestern Argentina, Palaeogeogr. Palaeocl., 153, 277–287, 1999. Wang, L. S., Yang, L. Z., and Li, T. B.: Evolution mechanism of Jiaochang earthquake landslide on Minjiang River and it s cont rolling, J. Geol. Hazards Environ. Preserv., 11, 195–199, 2000. Wang, L. S., Yang, L. Z., and Wang, X. Q.: Discovery of huge ancient dammed lake on upst ream of Minjiang River in Sichuan, China, J. Chengdu University of Technology: Science and Technology Edition, 32, 1–11, 2005. Wang, L. S., Wang, X. Q., and Xu, X. N.: What happened on the upstream of Minjiang River in Sichuan Province 20,000 <abbr>years</abbr> ago, Earth Sci. Front., 14, 189–196, 2007. Wang, P., Zhang, B., Qiu, W. L., and Wang, J. C.: Soft-sediment deformation structures from the Diexi paleo-dammed lakes In the upperreaches of the Minjiang River, east Tibet, J. Asian Earth Sci., 40, 865–872, 2011. Wang, S. B., Li, Y., and Xia, X. G.: Magnetostratigraphic Study of Lake Sediments in Jiaochang, Maoxian County, Sichuan, 426 pp., 2006. Wang, S. M. and Li, J. R.: Lake sediments – effective means to study the history of climate – an example from Qinghai Lake and Daihai Lake, Chinese Sci. Bull., 36, 54–56, 1991. Wang, X. Q.: The Environment Geological Information in the Sediments of Diexi Ancient Dammed Lake on the upstream of Mingjiang River in Sichuan Province, China, Ph.D. thesis, Chengdu University of Technology, Chengdu, China, 2009. Wassmer, P., Schneider, J. L., Pollet, N., and Schmitter-Voirin, C.: Effects of the internal structure of a rock-avalanche dam on the drainage mechanism of its impoundment, Flims sturzstrom and Ilanz paleo-lake, Swiss Alps, Geomorphology, 61, 3–17, 2004. Weidinger, J. T.: Case history and hazard analysis of two lake-damming landslides in the Himalayas, J. Asian Earth Sci., 16, 323–331, 1998. Wu, J. L., Li, S. J., and Wang, S. M.: Modern climatic signals recorded in Xincuo Lake sediments in Zoige Basin, eastern Tibetan plateau, China, J. Lake Sci., 12, 291–296, 2000. Yang, W. G.: Research of sedimentary record in terraces and climate vary in the upper reaches of Mingjiang River, china, Ph.D. thesis, Chengdu University of Technology, Chengdu, China, 2005. Zhang, Y., Zhu, L., and Yang, W., Luo, H., He, D., and Liu, J.: High resolution rapid climate change records of lacustrine deposits of Diexi Basin in the eastern margin of Qinghai-Tibet Plateau, 40–30 ka BP, Earth Sci. Front., 5, 91–98, 2009. Zhao, X. T., Qu, Y. X., and Zhang, Y. S.: Discovery of Shigu Paleolake in the Lijiang area, northwestern Yunnan, China and its significance for the development of the modern Jinsha River valley, Geol. Bull. China, 8, 960–969, 2007. Zhu, D. G., Meng, X. G., and Zhao, X. T.: Lake-level change of Namco Tibet since the Late Pleistocene and environment information of clay minerals in lacustrine deposits, J. Geomechan., 10, 300–309, 2004.