The Uralian foredeep is a classical marginal structure located on the foreland of the Late Paleozoic Uralian Orogen. It is subdivided into several depressions/sedimentation basins. This paper presents the analysis of the REE and Th distribution in the Middle Carboniferous and Lower Permian clay rocks of the Yuryuzan–Sylva Depression. This structure, like other depressions of the foredeep, is made up of diverse associations of the first sedimentation cycle clastic and clay rocks, which were formed during the orogen erosion. In the (La/Yb)_N–Eu/Eu* and (La/Yb)_N–Th diagrams, individual and average data points are confined to the field of bottom sediments of mouths of modern rivers draining volcanic provinces. This likely suggests a homogeneous composition of orogen provenance in the Carboniferous and Early Permian.

乌拉尔前缘是位于晚古生代乌拉尔造山带前陆的经典边缘结构。它分为几个凹陷/沉积盆地。本文介绍了尤里赞–西尔瓦De陷中石炭纪和下二叠统粘土岩中的稀土元素和distribution分布。像其他前凹的凹陷一样，这种结构是由造山带侵蚀过程中形成的第一沉积周期碎屑岩和粘土岩的各种组合组成的。在（La / Yb）_N –Eu / Eu *和（La / Yb）_N中–图表，单个数据点和平均数据点均限于排泄火山省份的现代河流口部底部沉积物的区域。这可能表明石炭纪和早二叠世造山带物源的均质组成。