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。

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.

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根据Kemmerling说，在他展开勘查的七十年前，这个隔离岩石壁与围绕火山边缘的岩石一样高，但是在他1929年来此前，岩石壁已经相继被侵蚀了。

According to Kemmerling this separating wall was as high as the surrounding crater rim 70 years before his survey, but it had subsequently eroded down by the time of his visit (Kemmerling, 1929).

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这是火星塔尔西斯盾状火山构造地区被风侵蚀的地貌，照片由美国宇航局的高分辨率科学成像实验相机摄于2010年7月31日。

Windblown features are visible on this shield volcano structure in Mars' Tharsis Region seen by NASA's HiRISE camera on July 31st, 2010. (NASA/JPL/University of Arizona)

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