沖ちゅう積せき統とう

noun

alluvial series

Geological term for a sequence of alluvial deposits. Used in stratigraphy and sedimentology.

• この地ち域いきの沖ちゅう積せき統とうは主おもに砂さ礫れきからなる。

  The alluvial series in this area consists mainly of sand and gravel.