Gypsum Deltas at the Holocene Dead Sea Linked to Grand Solar Minima

Unique gypsum structures: large capes (termed “gypsum deltas”) and small pitted gypsum mounds are exposed along the western shores of the currently retreating Dead Sea, the hypersaline terminal lake in the Dead Sea Basin. The gypsum deltas were formed during time intervals of low lake stands (∼420 ± 10 m below mean sea level), when sulfate-rich Ca chloride brines discharged from the coastal aquifer via saline springs, mixed with the Dead Sea brine and precipitated the gypsum (outsalting process). The ages of formation of the gypsum structures coincide with times of North Atlantic cooling events and grand solar minima suggesting a direct impact of the latter on the Dead Sea hydrology and high sensitivity of the regional hydrology (controlling lake level) to global solar-related events. The temporal occurrence and numbers of the gypsum structures appear to follow the Hallstatt Cycle that approaches minima at ∼3,000–2,000 years before present.