1·Igneous and metamorphic rocks are more compact, commonly crystalline, and rarely contain spaces between grains.
火成岩和变质岩比较致密，通常是结晶性的，颗粒之间很少有空隙。
2·Some very ancient sediments were no longer recognizable, having been converted to igneous and metamorphic rocks in the course of mountain building.
在造山的过程中，一些非常古老的沉积物已被转化为火成岩和变质岩，已经无法辨认了。
3·Rather than matching the ages of the zircons, the researchers note, the ages of the inclusions matched the ages of the metamorphic minerals surrounding the zircons.
研究人员发现，这些包体的年代与锆石样本周围的变质矿物的年代相当，而与包裹它们的锆石样本年代不符。
4·Daniels says Western Australia's metamorphic rocks contain more iron than the igneous rocks on the east coast, making some of the beaches a more orangey-red colour.
丹尼尔说澳大利亚西海岸的变质岩比东海岸的岩浆岩含铁成分高，因此沙滩呈现橙红色。
5·Gneiss, a metamorphic rock, can be commonly found in Precambrian areas.
片麻岩，变质岩，可以发现，在常见的前寒武纪地区。