The erosional evolution of the Late Permian basaltic source-to-sink sedimentary system in the western South China and its metallogenic effect

<p indent="0mm">The source-to-sink (S2S) sedimentary system links the erosional geomorphic area with the sedimentary geomorphic area through sedimentary path and transforms the erosional geomorphic evolution into the geological historical record through the transport and accumulation of sediments from source to sink. Based on the brief discription of researches on the geomorphic erosion in the S2S system, we have completely summarized the research progresses of the late Permian S2S sedimentary system in the western South China. Detrital sediments of this Late Permian S2S sedimentary system were mainly sourced from the weathering and erosion of rocks in the Emeishan large igneous province and then were transported southeastward into the Youjiang Basin, and deposited in various sedimentary environments of the basin in which a complete sedimentary sequence from terrestrial facies, coastal-shallow marine facies and deep-water basin facies was preserved. Based on the sedimentology and sedimentary provenance analysis of the terrestrial Xuanwei Formation, we have improved the S2S sedimentary system and further confirmed the evolution of erosional landforms of the western South China and its driving mechanism during the middle Wuchiapingian age. Through detailed sedimentological analysis of ore-bearing successions in the lower part of the Xuanwei Formation, we have established the alluvial fan-wetland sedimentary facies association model and determined the early Wuchiapingian weathering-sedimentary mineralization effect.