Mudcrack

[4] Syneresis cracks are broadly similar features that form from underwater shrinkage of muddy sediment caused by differences in salinity or chemical conditions,[1] rather than aerial exposure and desiccation.

Allen (1982) proposed a classification scheme for mudcracks based on their completeness, orientation, shape, and type of infill.

When mud curls form, the water that is inside the sediment begins to evaporate causing the stratified layers to separate.

Abandoned river channels, floodplain muds, and dried ponds are localities that form mudcracks.

[8] Similar features also occur in frozen ground, lava flows (as columnar basalt), and igneous dykes and sills.

[9] Polygonal crack networks similar to mudcracks can form in human-made materials such as ceramic glazes, paint film, and poorly made concrete.

Mudcrack patterning at smaller scales can also be observed studied using technological thin films[10][11] deposited using micro and nanotechnologies.

Bottom-of-bed preservation occurs when mudcracks that have already formed and are completely dried are covered with fresh, wet sediment and are buried.

[2] In these cases, the original mud cracks will erode faster than the newer material that fills the spaces.

This type of mudcrack is used by geologists to determine the vertical orientation of rock samples that have been altered through folding or faulting.