stratified sampling of water

例句：

1. 1.The soil is stratified with layers of different minerals.
   土壤分层，含有不同矿物质的层次。
2. 2. The rock formation is a classic example of stratified sedimentary rock.
   这种岩石形成是典型的层状沉积岩的例子。
3. 3. The geologist studied the stratified layers of the ancient lake bed.
   地质学家研究了古代湖泊底部的分层层次。