@article {2945, title = {Hydrological and thermodynamic controls on late Holocene gypsum formation by mixing saline groundwater and Dead Sea brine}, journal = {Geochimica et Cosmochimica Acta}, volume = {316}, year = {2022}, month = {Jan-01-2022}, pages = {363 - 383}, abstract = {The rapid retreat of the Dead Sea during the past four decades led to the exposure of unique structures of massive gypsum along the shores. Many of these structures (having the shape of mounds) are associated with the activity of Ein Qedem-type saline springs that currently discharge Ca-chloride brine to the lake. Field observations, radiocarbon dating of aragonite (within the gypsum mounds) that yield ancient ages, and the narrow range of 834S and 818O values (d34Sgyp: 14.1-16.9\%; d18Ogyp: 14.4-16.5\%) indicates that the formation of the gypsum structures is related to the mixing of brines: the Dead Sea brine and ancient (last glacial) Ein Qedem type brine. These are Ca-chloride brines having different salinities and sulfur concentrations that satisfy conditions of an outsalting process whereby supersaturation of gypsum is attained by the mixing of these two brines in the offshore shallow water environment. Thermodynamic calculations (using the PHREEQC software) show that gypsum outsalting occurred when both brines were enriched with sulfate as compared to the present. The Ein-Qedem brine had higher sulfate when subjected to less intensive bacterial sulfate reduction. The Dead Sea was characterized by higher sulfate concentrations during intervals of low lake stands. The conditions of higher sulfate concentrations and enhanced discharge of the saline springs occurred repeatedly in the Dead Sea between -6.6 to 0.6 ka and were intermittent with periods of enhanced supply of sulfate to the lake by freshwaters.}, keywords = {BrinesSaline springs, Dead Sea, Hydroclimate, Lacustrine Gypsum, Outsalting, Thermodynamic modeling}, issn = {00167037}, doi = {10.1016/j.gca.2021.10.002}, url = {https://www.webofscience.com/wos/woscc/full-record/WOS:000730092400010?AlertId=ab9062f8-b111-4f95-a2b8-66e7afac0471\&SID=8Dkzxr6qseeJz1VEtb3}, author = {Weber, Nurit and Antler, Gilad and Lazar, Boaz and Stein, Mordechai and Yechieli, Yoseph and Gavrieli, Ittai} } @article {2918, title = {RADIOCARBON RESERVOIR AGES IN THE HOLOCENE DEAD SEAABSTRACT}, journal = {Radiocarbon}, volume = {62}, year = {2020}, month = {Jan-10-2020}, pages = {1453 - 1473}, abstract = {The sources and fate of radiocarbon (C-14) in the Dead Sea hypersaline solution are evaluated with C-14 measurements in organic debris and primary aragonite collected from exposures of the Holocene Ze{\textquoteright}elim Formation. The reservoir age (RA) is defined as the difference between the radiocarbon age of the aragonite at time of its precipitation (representing lake{\textquoteright}s dissolved inorganic carbon pig) and the age of contemporaneous organic debris (representing atmospheric radiocarbon). Evaluation of the data for the past 6000 yr from Dead Sea sediments reveal that the lake{\textquoteright}s RA decreased from 2890 yr at 6 cal kyr BP to 2300 yr at present. The RA lies at similar to 2400 yr during the past 3000 yr, when the lake was characterized by continuous deposition of primary aragonite, which implies a continuous supply of freshwater-bicarbonate into the lake. This process reflects the overall stability of the hydrological-climate conditions in the lake{\textquoteright}s watershed during the late Holocene where bicarbonate originated from dissolution of the surface cover in the watershed that was transported to the Dead Sea by the freshwater runoff. An excellent correlation (R-2=0.98) exists between aragonite ages and contemporaneous organic debris, allowing the estimation of ages of various primary deposits where organic debris are not available.}, keywords = {aragonite, Dead Sea, Holocene, radiocarbon, reservoir ages}, issn = {0033-8222}, doi = {10.1017/RDC.2020.28}, url = {https://apps.webofknowledge.com/InboundService.do?product=WOS\&Func=Frame\&DestFail=http\%3A\%2F\%2Fwww.webofknowledge.com\&SrcApp=search\&SrcAuth=Alerting\&SID=8AkJOJLKFU3j5nkGaRI\&customersID=Alerting\&mode=FullRecord\&IsProductCode=Yes\&AlertId=4d48b20a-7d27-4fa2-}, author = {Weber, Nurit and Lazar, Boaz and Stern, Ofra and Burr, George and Gavrieli, Ittai and Roberts, Mark and Kurz, Mark D and Yechieli, Yoseph and Stein, Mordechai} }