A Quaternary study by mineral compositions along salty-clay surfaces of Sabzavar dry-lake playa

We studied mineral and deposition records in a dry lake playa, Sabzevar, northeastern, Iran. For sampling soil and depositional records, 12 samples were taken along Playa surfaces including firm puffy ground, clay-carbonate plain, and salty pan with the dominance of Halite salts. All profiles were excavated by hand auger with a 5 cm diameter head to a depth of ~5 cm. Sediment analysis was carried out through soil physicochemical properties and XRD/XRF were done for mineralogy. According to the XRF results, main minerals of quartzite and calcite are observed over the playa. After XRD results, the major minerals in the sediments were categorized as quartzite, halite, calcite, and gypsum. Afterward, the minerals of halite, calcite, gypsum indicate dominant evaporate process. Enrichment of evaporate minerals on the surface grounds are an evidence of a variation hydrostatic level of Sabzevar playa, which can be a signal for a wet lake in the past and dried one in the present day.