1) Sedimentary structure
Found on
https://www.crosswordclues.com/clue/mudcrack
Mudcracks (also known as desiccation cracks or mud cracks) are sedimentary structures formed as muddy sediment dries and contracts. Crack formation also occurs in clayey soils as a result of a reduction in water content. == Formation == Naturally forming mudcracks start as wet, muddy sediment desiccates, causing contraction. A strain is developed ...
Found on
http://en.wikipedia.org/wiki/Mudcrack
A fracture that develops at the top of a layer of fine grained, muddy sediment when it is exposed to the air, dries out, and then shrinks.
Found on
http://www.encyclo.co.uk/local/22291
No exact match found.
