洪こう積せき層そう

noun

diluvium; diluvial formation

Geological term for Pleistocene deposits; now often replaced by 更新統 (こうしんとう) in modern stratigraphy, but still encountered in older literature and some contexts.

• この地ち域いきの洪こう積せき層そうからは多おおくの化か石せきが発はっ見けんされている。

  Many fossils have been discovered in the diluvial deposits of this region.