Frontiers in Geochemistry - Contribution of Geochemistry to the Study of the Earth
Frontiers in Geochemistry - Contribution of Geochemistry to the Study of the Earth
复制标题
地球化学前沿 - 地球化学对地球研究的贡献
DOI：
10.1002/9781444329957.ch2
复制
发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Hawkesworth C
中科院分区：
文献类型：
--
作者：
Hawkesworth C
大陆地壳是过去4.4Ga以来地球上条件的主要记录。暴露的地壳岩石中，只有不到10%的年龄超过2.5Ga，但到那时，50%的大陆地壳可能已经稳定下来。一个关键的档案是像锆石这样的矿物，它们可以精确地测定年代，并保存强大的同位素和微量元素信号。早期地壳的大部分成分是镁铁质的，太古代晚期标志着从保存潜力普遍较差的时期过渡到地质记录似乎受到形成岩石的构造环境的偏见的时期。
The continental crust is the principal record of conditions on the Earth for the last 4.4 Ga. Less than 10% of the crustal rocks exposed are older than 2.5 Ga, and yet 50% of the continental crust may have stabilized by that time. A key archive is minerals like zircon which can be precisely dated and preserve robust isotope and trace element signals. Much of the early crust was mafic in composition, and the late Archaean marks the transition from a period of uniformly poor preservation potential to one in which the geological record appears to be biased by the tectonic setting in which the rocks were formed.