许多无脊椎动物的碳酸钙贝壳中可以找到其形成时自然条件的证据。
Many invertebrates have shells of calcium carbonate that bear evidence of the physical conditions in which they formed.
目前这个地区已有1200余件刻有文字的文物出土，其中包括涂墙，陶罐，动物骨头和贝壳，其活跃时间大约为公元前600年至公元前400年之间。
Some 1200 inscribed objects have been found, ranging from painted wallsto pots, bones and shells. The date of the script appears to liesomewhere between 600 and 400 BC.
今年3月，通过对冰岛一带贝壳的研究发现，其硬壳氧同位素的水平会随水温的变化而产生差异。
A study this March of clamshells taken from Iceland found that the levels of oxygen isotopes in the shell layers varied depending on the temperature of the water in which they formed.
应用推荐