Honeycomb weathering
Honeycomb weathering, also known as honeycombs, honeycombed sandstone, is a form of cavernous weathering that consists of regular, tightly adjoining, and commonly patterned cavities that are developed in weathered bedrock; are less than in size; and resemble a honeycombed structure. Honeycombs also been called alveoli, lacework, stonelace, fretting, or miniature tafoni weathering. The size at which honeycombs are differentiated from tafoni varies greatly in the scientific literature and lacks an official consensus.
Distribution
Honeycomb weathering typically develops in siliceous, either coarse-grained sedimentary or coarsely crystalline plutonic rocks. It can be found in all climate types, but is most prolific in salt-rich environments, such as deserts and coastal zones. The common factors in the environments in which it is found are high salt concentrations and frequent or occasional desiccating conditions. Honeycomb weathering is rarely associated with highly soluble rock such as limestone or dolomite. Honeycombs also occur in stone structures, e.g. buildings and breakwaters, where a rate of development can be established. Honeycomb weathering has been found to have formed in greywacke blocks since they were used to build seawalls on the coast of Southeast Australia in 1943 and 1949.Honeycomb and other forms of cavernous weathering are likely as characteristic of the weathering of sandstones as fluting is of limestones, but it is not uniformly or universally developed. For example, in some cliffs, large expanses of the rock face exhibit surface weathering and cavernous weathering of metric dimensions. However, other rock faces are pitted between closely spaced bedding and vertical joint planes. In the southwestern United States, sheer faces of Coconino and Supai Sandstones cropping out along the sides of the Grand Canyon are only sparsely honeycombed. Also, the tall spires of De Chelley Sandstone at Monument Valley in Utah are unmarked by such weathering. In contrast, the Aztec Sandstone of The Valley of Fire in Nevada exhibits delicate and widespread honeycomb and other cavernous weathering. The difference may lie in contrasting patterns of permeability and jointing and resulting variations in the flow of waters through these sandstone.