The Yichang gravel layers distribute largely at the Yichang，Zhijiang and Songzi area，which have important significance for the research of stratigraphic division，geomorphic evolution，ancient environmental changes of the Jianghan Plain and the middle Yangtze River，even formation and evolution of the Yangtze River. Based on previous research of our studying team，a total of six profiles were chosen in this paper. Here，heavy mineral characteristics of very fine sand fraction (63-125μm) was selected from bulk samples were analyzed. The results revealed that heavy mineral assemblages of the fine grained sediments from the gravel layers are almost the same which meant zircon，epidote，leucoxene，hematite limonite，ilmenite and magnetite. Relation of the source to sink shows source rock types reflected by heavy mineral assemblages distributed primarily in the Jinshajiang，Minjiang and Wujiang drainage basin，besides Western Three Gorges. Meantime heavy mineral assemblages of the sediments are similar to those of the modern Yangtze and the low terrace sediments，which is showed by comparison the heavy mineral assemblage with the modern Yangtze and the main rivers in the Jianghan Plain. Based on the comprehensive analysis above，together with the early research on formation age of the Yichang gravel layers，we conclude that the Yichang gravel layers were the alluvial fan formed when the Yangtze River cut through the Three Gorges in the Early Pleistocene，approximately 1.0Ma BP.