Eroded [verb]

In these channels the waters have chafed, ground, abraded, eroded for centuries which man cannot number.

We ride between steep cliffs down a deeply eroded valley, and side valleys run in with narrow deep openings.

Between its terminal moraines and the older moraines we have skirted, a rather voluminous stream has eroded its valley.

During the ice age many of these deposits were eroded and others were piled with boulders.

Whatever the cause, its outlet waters changed and eroded the now famous and splendidly colored cañon of the Yellowstone.

Two ice-eroded cañons begin in the southern rim and extend down the slope.

During the ages it has transported an inconceivable bulk of eroded material to the ocean.

The amphitheaters which the young geologist mistook for craters are now known to be glacier basins eroded by ice.

The tops of the walls, while rough and greatly eroded, are approximately level.

The caravan moved along the high ridge, a narrow trail that wound back toward Martian Haven along the edge of the eroded cliffs.