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

农民发现这底下的沉积物很肥沃。

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

各时期形成的砂岩和粒屑灰岩集体,为油气集提供了有利的场所。

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个砂矿床，供给砂矿的含岩体具多期多源特点。