Cross Bedding in Dali, Yunnan
What appears to be a textural painting is actually a process called cross-bedding, where Neogene sandstone sediments in a riverbed are embedded with coal sediments. Such patterns are influenced by the densities of the materials and the direction of the flow of sediments. Cross-bedding such as this one found in the Dali region of Yunnan, China, suggests a past environment of flowing water in the area. One yuan coin for scale.