The upper Jinsha River in the southeastern margin of the Tibetan Plateau, characterized by intense tectonic activity and steep terrain, is a high-risk zone for landslide-damming events. This study focuses on the Woda paleo-landslide-dammed lake, reconstructing its chronology, scale, and geomorphic effects through optically stimulated luminescence (OSL) dating and a "dam-lake synergy analysis." OSL dating results indicate that the landslide-damming event occurred at ~60 ka, corresponding to the late Marine Isotope Stage 4 (MIS 4). During this period, diurnal temperature fluctuations near freezing thresholds promoted repeated freeze-thaw cycles, accelerating bedrock fracturing and preconditioning slope instability. The landslide involved a volume of 1.93 × 10⁸ m³, forming a 109-m-high dam that impounded a lake with a maximum surface area of 21.04 × 10⁶ m² and storage capacity of 137.61 × 10⁷ m³. Lacustrine sediments indicate a minimum water level corresponding to a reduced area of 11.93 × 10⁶ m² and capacity of 53.03 × 10⁷ m³. A 42-m vertical difference between the frontal dam elevation (3,100 m a.s.l.) and the top of lacustrine deposits (3,058 m a.s.l.), combined with evidence of rapid sediment accumulation, suggests short-lived lake existence followed by catastrophic dam breaching. By integrating landslide dam morphology, lacustrine stratigraphy, and multi-proxy sedimentary evidence, this study addresses systematic biases inherent to traditional lacustrine sediment-based reconstructions. It reveals the triggering mechanism of mega-landslides driven by climate-tectonic coupling and provides a methodological framework for assessing landslide-flood cascading hazards in tectonically active regions. The findings underscore the need to address slope destabilization risks induced by freeze-thaw processes under current climate warming.

Liqin Zhou, Mingyue Qin. Reconstruction of the Scale and Chronology of the Woda Paleo-Landslide-Dammed Lake in the Upper Jinsha River. Academic Journal of Environment & Earth Science (2025), Vol. 7, Issue 3: 16-21. https://doi.org/10.25236/AJEE.2025.070302.

[1] Ouyang C, An H, Zhou S, et al. Insights from the failure and dynamic characteristics of two sequential landslides at Baige village along the Jinsha River, China[J]. Landslides, 2019, 16: 1397-1414.

[2] Korup O and Tweed F. Ice, moraine, and landslide dams in mountainous terrain[J]. Quaternary Science Reviews, 2007, 26(25-28): 3406-3422.

[3] Guo X, Sun Z, Lai Z, et al. Optical dating of landslide-dammed lake deposits in the upper Yellow River, Qinghai-Tibetan Plateau, China[J]. Quaternary International, 2016, 392: 233-238.

[4] Jiang H, Xue M, Xu H, et al. Provenance and earthquake signature of the last deglacial Xinmocun lacustrine sediments at Diexi, East Tibet[J]. Geomorphology, 2014, 204(1): 518-531.

[5] Ping W, Zhang B, Qiu W, et al. Soft-sediment deformation structures from the Diexi paleo-dammed lakes in the upper reaches of the Minjiang River, east Tibet[J]. Journal of Asian Earth ences, 2011, 40(4): 865-872.

[6] Liu W, Carling P A, Hu K, et al. Outburst floods in China: A review[J]. Earth-Science Reviews, 2019, 197: 102895.

[7] Liu W, Hu K, Carling P A, et al. The establishment and influence of Baimakou paleo-dam in an upstream reach of the Yangtze River, southeastern margin of the Tibetan Plateau[J]. Geomorphology, 2018, 321(15): 167-173.

[8] Li Y, Chen J, Zhou F, et al. Identification of ancient river-blocking events and analysis of the mechanisms for the formation of landslide dams in the Suwalong section of the upper Jinsha River, SE Tibetan Plateau[J]. Geomorphology, 2020, 368: 107351.

[9] Wang H, Tong K, Hu G, et al. Dam and megafloods at the First Bend of the Yangtze River since the Last Glacial Maximum[J]. Geomorphology, 2020, 373(15): 107491.

[10] Xia M, Ren G M and Tian F. Mechanism of an ancient river-damming landslide at batang hydropower station, Jinsha river basin, China[J]. Landslides, 2023, 20(10): 2213-2226.

[11] Scherler D, Munack H, Mey J, et al. Ice dams, outburst floods, and glacial incision at the western margin of the Tibetan Plateau: A > 100 k.y. chronology from the Shyok Valley, Karakoram[J]. Geological Society of America Bulletin, 2014, 126(5-6): 738-758.

[12] Wang H, Cui P, Liu D, et al. Evolution of a landslide-dammed lake on the southeastern Tibetan Plateau and its influence on river longitudinal profiles[J]. Geomorphology, 2019, 343: 15-32.

[13] Johnsen T F and Brennand T A. The environment in and around ice-dammed lakes in the moderately high relief setting of the southern Canadian Cordillera[J]. Boreas, 2006, 35(1): 106-125.

[14] Wang H, Cui P, Zhou L, et al. Spatial and temporal distribution of landslide-dammed lakes in Purlung Tsangpo[J]. Engineering Geology, 2022, 308: 106802.

[15] Yu Y, Wang X, Yi S, et al. Late Quaternary aggradation and incision in the headwaters of the Yangtze River, eastern Tibetan Plateau, China[J]. Bulletin, Bulletin, 2022, 134(1-2): 371-388.

[16] Lai, Z. and Ou, X. Basic procedures of optically stimulated luminescence (OSL) dating. Progress in Geography, 2013,32: 683-693.

[17] Murray, A.S. and Wintle, A. Luminescence dating of quartz using an improved single-aliquot regenerative-dose protocol. Radiation Measurements,2000, 32(1): 57-73.

[18] Lai, Z., 2006. Testing the use of an OSL standardised growth curve (SGC) for De determination on quartz from the Chinese Loess Plateau. Radiation Measurements, 41(1): 9-16.

[19] Roberts H and Duller G A. Standardised growth curves for optical dating of sediment using multiple-grain aliquots[J]. Radiation measurements, 2004, 38(2): 241-252.

[20] Liu W, Lai Z, Hu K, et al. Age and extent of a giant glacial-dammed lake at Yarlung Tsangpo gorge in the Tibetan Plateau[J]. Geomorphology, 2015, 246(1): 370-376.

[21] Prescott J R and Hutton J T. Cosmic ray contributions to dose rates for luminescence and ESR dating: large depths and long-term time variations[J]. Radiation measurements, 1994, 23(2-3): 497-500.

[22] Lai, Z. and Brückner, H. Effects of Feldspar Contamination on Equivalent dose and the Shape of Growth Curve for OSL of Silt-Sized Quartz Extracted from Chinese Loess. Geochronometria, 2008, 30: 49-53.

[23] Costa J E and Schuster R L. The formation and failure of natural dams[J]. Geological Society of America Bulletin, 1988, 100(7): 1054-1068.