Reference work entry
The undulating granite hilltop of Daqingshan in Hexigten Banner, Inner Mongolia, contains hundreds of circular, oval, and irregularly shaped caves with large openings and great depths that are shaped like a mortar, a cylinder, a bowl or a dish. Unlike the potholes carved by flowing water along rivers in southern China, there is no indication of water flowing into the cave. They have two main formation mechanisms: congelifraction or wind erosion, but both may occur (Fig. 28).
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