A sabkha () is a coastal, supratidal mudflat or sandflat in which evaporite-saline minerals accumulate as the result of semiarid to arid climate. Sabkhas are gradational between land and intertidal zone within restricted coastal plains just above normal high-tide level. Within a sabkha, evaporite-saline minerals sediments typically accumulate below the surface of mudflats or sandflats. Evaporite-saline minerals, tidal-flood, and aeolian deposits characterize many sabkhas found along modern coastlines. The accepted type locality for a sabkha is at the southern coast of the Persian Gulf, in the United Arab Emirates. Sabkha is a phonetic transliteration of the Arabic word used to describe any form of salt flat. A sabkha is also known as a sabkhah, sebkha, or coastal sabkha. The term sabkha has also been used as a general term for any flat area, coastal or interior, where, as the result of evaporation, salt and other evaporite minerals precipitate near or at the surface. The term continental sabkha is used for such environments found within deserts. Because of the confusion created by using sabkha for salt flats and playas, it has been proposed that the usage of this term be abandoned for playas and other intracontinental basins and flats. Origin and development The Abu Dhabi Sabkha The origin and progression of coastal sabkha development at the southern shore of the Persian Gulf was first discussed in detail in the seminal paper by Evans et al. 1969. The southern shoreline of the Persian Gulf is a shallow, low-angle carbonate ramp characterised by an evaporitic supratidal system passing offshore, via a broad carbonate–evaporite intertidal environment, into a carbonate-dominated subtidal system. This is a low-energy setting with a small tidal range (1–2 m) and low wave energy as a result of the limited fetch. High rates of evaporation result in salinities of 45–46 g l−1 along the open-marine coast of Abu Dhabi and up to 89 g l−1 in more-restricted lagoons. The coast of Abu Dhabi is locally protected from open-marine conditions by a number of peninsulas and offshore shoals and islands associated with the east–west trending Great Pearl Bank. Khor lagoon In the khor-lagoon-sabkha model, an initial rise in sea-level floods coastal areas and creates shallow water features. If the features silt up, or the land rises, or the sea level falls, then the trapped water evaporates, leaving a flat salt pan, or sabkha. If the coastal region has irregular topography, then the