archaean era造句

• It was early in the archaean era , 3 . 8 to 2 . 5 billion years ago , that life first appeared on earth
  它在及早在archaean时代, 3 . 8到2 . 5十亿年前,生活第一次出现在地球上。
• It suggests that gold accumulation occurred in the every main stage of geologic history of fujian from late - archaean era to quaternary period but the scale and the feature of the gold accumulation are different in different stage and yanshan metallogenic epoch is the most important period of mineralization of fujian gold deposits
  提出福建省内自晚太古代至第四纪的各个地质历史发展的主要阶段均有金的富集作用，但不同阶段所形成的金富集规模及特征明显有别，燕山期为福建省金矿最重要的成矿期。