Abstract：Soft-sediment deformation structures，which contain cylindrical structure，pillow structure，load structure and curly bedding structure，were largely preserved in the Middle-Upper Triassic in Yima region, western Henan Province.Most of them occurred in the upper part of fluvial and deltaic deposits，which represents fine-grain and more water-contained sediments.Although it is beneficial to liquefaction of sediments， the trigger of soft-sediment deformation structures is the palaeoearthquake activities from the Qinling Orogen.Comparison of soft-sediment deformation assemblages from the Youfangzhuang Formation with data from the Chunshuyao Formation reveals the initial orogeny of the Qinling Orogenic Belt happened in the later Middle Triassic and more intense activities in the Late Triassic.
. Soft-sediment deformation structures caused by palaeoearthquake in the Middle-Late Triassic in Yima area，western Henan Province[J]. JOPC, 2011, 13(6): 635-644.
