the dyke (or dike in american english) intrudes through the even older rocks of african craton, the core of oldest rocks forming the continent of africa.
堤防(或美式英语堤)通过侵入非洲克拉通形成的最古老的非洲大陆巖石核心的更老的巖石。
on an arid outcropping of basalt in northwestern australia, some of the oldest rocks on earth lie exposed to the fierce sun.
在澳大利亚西北部露出地面的一块光秃秃的玄武石上,部分地球上最古老的巖石正暴露在酷阳之下。
if the layers of rock in a region are not disturbed, the oldest rocks are at the bottom, the newest at the top.
如果一个地区的巖层没有被弄乱,最古的巖石在底部,最新的在顶部。
the oldest rocks on earth have been discovered in canada, offering scientists a glimpse at the origins of the planet, announced scientists in a study to be published friday.
科学家将于本周五发表的一项研究报告中公布,他们在加拿大发现了目前地球上最古老的巖石,这一发现为科学家研究地球起源提供了新的线索。