The clay deposits are scattered all over, in ancient volcanic surfaces and heavily cratered highland regions, some of which have apparently been exposed by erosion only recently.
粘土沉积分布在古代的火山表面和坑坑洼洼的高原地区，其中一些显然是最近才由于侵蚀而暴露出来的。
2
This close up of Dione reveals its cratered and fractured icy surface.
这张土卫四（Dione）的近距离特写照片展示了其坑坑洼洼支离破碎的冰冷表面。
3
Epimetheus, as pictured above, is actually well behind the heavily cratered Rhea.