Journal de géologie et géophysique
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Origins of Soft-Sediment Deformation Structures from the Batang Paleodammed Lakes in the Upper Jinsha River, SE Tibetan Plateau

Yongbo Teng, Jian Chen, Zhijiu Cui, Weichao Li and Yan Li

Multiple levels of preserved soft-sediment deformation structures occur in sediments deposited in the paleodammed lakes in the Batang-Zhongza reaches of the upper Jinsha River Valley, southeast Tibetan Plateau. These deformation structures include folded layers, convoluted layers, ball-and-pillow structures, recumbent lamination, waterescape structures, and small-scale landslide. Combining the assessments of depositional facies, potential triggers, paleoenvironmental context, we conclude that the probable trigger agents of this deformation were earthquakes, slides, and debris flows. The seismically-induced soft-sediment deformation structures provide new substantial evidence for the existence of active tectonics and paleo-earthquakes in the Batang area since the Holocene.