Abstract：Affected by the collision between Cathaysian Plate and Yangtze Plate, the ancient uplifts around Upper Yangtze Sea area developed during the Silurian period, and the sediment sources in the study area were complex. In order to investigate the sedimentary environment of Silurian strata in Yongshun area of Northwestern Hunan, the authors in this paper studied the REE geochemical characteristics of Silurian sandstone in this area. The results show that the differentiation between LREE and HREE is obvious in samples, with rich LREE and flat HREE. Eu is of obviously negative anomaly, and Ce is normal. The palaeoenvironment of the Silurian period in the study area was anoxic and weak reduction environment, implied by Ceanom results. The geochemical characteristics of REE indicate that the sedimentary rate of the Silurian period in the study area is fast. Combined with structural features and achievements in palaeogeography of predecessors, the authors in this paper suggest that the provenance of the study area comes from the sedimentary rock in Xuefeng Mountain uplift, which can provide some reference for lithofacies paleogeography restoration of Silurian in Northwestern Hunan.
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2023, Vol. 10 
