The farmers found the alluvial deposits at the mouth of the river very fertile.

农民发现这条河口底下的沉积物。

Four alluvial deposits distributing along Yuanjiang river and the diamondiferous rocks that supply diamonds to these placer deposits have striking properties of varied sources and multi-phases.

沅水流域分布4个金刚石砂矿床，给金刚石砂矿的含金刚石岩体源特点。

Mainly developed are fan - delta, deep lake turbidite and calcirudite deposit, and also alluvial fan deposit in early period.

各时形成的砂岩和粒屑灰岩储集体,为油气储集提了有利的场所。