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With the objective of establishing a distinction between deformation structures caused by freeze/thaw cycles and those resulting from seismic activity,we studied three well-exposed alluvial deposits in a section at Dogai Coring,north Qiangtang Basin,Tibetan Plateau.Deformation is present in the form of plastic structures (diapirs,folds and clastic dykes),brittle structures (micro-faults) and cryogenic wedges.These soft-sediment deformation features (except the micro-faults) are mainly characterized by meter-scale,non-interlayered,low-speed and low-pressure displacements within soft sediments,most commonly in the form of plastic deformation.Taking into account the geographic setting,lithology and deformation features,we interpret these soft-sediment deformation features as the products of freeze/thaw cycles,rather than of earthquake-induced shock waves,thus reflecting regional temperature changes and fluctuations of hydrothermal conditions in the uppermost sediments.The micro-faults (close to linear hot springs) are ascribed to regional fault activity;however,we were unable to identify the nature of the micro-faults,perhaps due to disturbance by subsequent freeze/thaw cycles.This study may serve as a guide to recognizing the differences between deformation structures attributed to freeze/ thaw cycles and seismic processes.