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。

youdao

The ancient carbonate ancient karst of Well TZ16-TZ24 area can be divided into two main categories, the erosion karst and deep karst.

塔中16 - 2 4井区奥陶系碳酸盐岩古岩溶主要分为侵蚀面岩溶和深部岩溶。

youdao

The formation mechanism is the flowing water trace to the source erosion-rock collapse-ancient slope withdrawal.

形成机制是流水溯源侵蚀—岩石块体崩塌—谷坡后退。

youdao

And sometimes we find that vast mountains of it have been worn down by erosion and that the cassiterite is now spread through the silt and sand of an ancient estuary.

FORBES: After Conflict Minerals Comes The Death Metal: Tin. And It's Apple's Fault Again.