The facing is white marble over granite backing sitting on a bluestone gneiss foundation.

外层为白色大理石，内衬花岗岩，坐落在蓝色片麻岩地基之上。

Here in a remote corner of the Northwest Territories, hundreds of miles, and 1.6 times more kilometers away from the nearest human settlement is a geologic formation called the Acasta Gneiss.

在西北地区一个偏远角落，距离最类居地有英里， 换算成公里则是其1.6倍之遥地方， 存在着一种地质构造， 名为阿卡斯塔片麻岩。

This is the 4.02-billion-year-old Idiwhaa unit of the Acasta Gneiss.

这是阿卡斯塔片麻岩中40.2亿年高龄伊迪瓦单元。

Gneiss has alternate bands of light and dark minerals and can form from a variety of different rocks.

片麻岩具有交替浅色和深色 矿物带，可以由各种不同岩石形成。