Sediments geochemistry of geological units of Sarakhs region: implications to the dust emission

Abstract

One of the critical factors dust sources less consideration is the role of geology and geomorphology as a source of dust emission. Geological units are one of the factors involved in the release of dust particles and the production of sediment. Lithological components with high sensitivity to alteration, weathering, and erosion, play an influential role in the emission and distribution of dust particles. Based on research, Sarakhs County is one of the critical corridors of wind erosion and dust storms in Iran that is affected by 120-days winds of Sistan The sensitivity of the geological units to wind and water erosion in this area categories from medium to very high. To identify the chemical elements of the geological units and their roles in dust emission, soil samples were collected from the surface, and sub-surface layers of the geological units and airborne dust were also collected from the atmosphere. Samples were analysed by induction spectroscopy to determine their chemical elements. To identify the origin of dust and its relationship with geological units and also their classification, factor and cluster analysis was performed. The results of factoring and clustering analysis showed the Sarakhs region with chemical elements sodium, zinc, lanthanum, arsenic, niobium, cadmium, nickel, lead, zinc, lithium, strontium, sulfur, sodium is in factor one with an evaporative and chemical origin, and with elements of aluminum e, iron, cobalt, thorium, manganese, boron, and titanium is in factor two with a detrital and terrestrial origin. Also, the chemical elements of dust in rural areas of Bazangan, Shorlugh, Baghbghoo, Padeh, and Baghak are in the same group as the geological units of Abe-Daraz, Chehel-e-Kaman, Quaternary deposits, bitter water, and Khangiran and have a common origin. The chemical elements barium, arsenic, sulfur, thorium, nickel, and lithium were introduced based on enrichment factors of human origin (chemical-evaporative).

Keywords

• dust
• geochemistry
• geological units
• enrichment factor
• sarakhs