中文摘要：

豫西济源中三叠世油房庄组下部发育曲流河沉积，以细砂、粉砂和粉砂质泥岩为主，局部含泥砾和粗砂岩。根据Miall的岩相分类法，油房庄组发育有17种岩相，主要有Sts、Sps、Sws、Fh、Fr、Fc、Ch和Cr等，可归纳为代表曲流河不同发展阶段的7种岩相组合类型。根据岩相类型和沉积构造特征，曲流河沉积识别出3个沉积亚相和8个沉积微相，其中河道亚相包括河道滞留沉积微相和边滩沉积微相；堤岸亚相包括天然堤沉积微相和决口扇沉积微相；洪泛平原亚相由近端洪泛平原沉积微相、远端洪泛平原沉积微相、永久性河漫湖泊微相和暂时性河漫湖泊微相组成。研究区河流曲率P为0．64，属于低弯度曲流河沉积。

英文摘要：

The meandering fluvial deposits, preserved in Middle Triassic Youfangzhuang Formation of Jiyuan Area, western Henan, comprise mainly fine sandstone, siltstone and silty mudstone interbedded with conglomerate and coarse sandstone. According to Miall＇ s lithofacies classification, seventeen lithofacies can be recognized from Youfangzhuang Formation, the main lithofacies are Sts, Sps, Sws, Fh, Fr, associations. Based on the features of lithofacies types and Youfangzhang Fc, Ch and Cr, which can be aligned to seven lithofacies sedimentary structures, the fluvial sedimentary facies of Fm. can be subdivided into three sublithofacies and eight microlitofacies. The fluvial channel sinuosity （P） is 0. 64, the fluvial deposits belong to low-sinuosity meandering fluvial deposits