Eolianite

Eolianite or aeolianite is any rock formed by the lithification of sediment deposited by aeolian processes; that is, the wind. In common use, however, the term refers specifically to the most common form of eolianite: coastal limestone consisting of carbonate sediment of shallow marine biogenic origin, formed into coastal dunes by the wind, and subsequently lithified. It is also known as kurkar in the Middle East, miliolite in India and Arabia, and grès dunaire in the eastern Mediterranean.

They are understood to have formed during the last one million years, and it is thought that the timing of deposition is related to sea level, but the nature of that relationship remains the subject of some debate.

Eolianite occurs in many parts of the world. It occurs most extensively between the latitudes of 20° and 40° in both hemispheres, with little nearer the equator, and virtually no deposits nearer the poles. There is no apparent difference in distribution between the hemispheres, but if the extent and thickness of deposits are taken into account, the Southern Hemisphere has the bulk of eolianite.