Diatomites of the south Ardebil
During geological investigations in the Ardebil-Astara quadrangle, fish fossil-bearing diatomite horizons explored in the Neogene layers of south Ardebil. These layers are equivalent to the diatomite beds of Tabriz. Because of applications of diatomite in various industries, preliminary studies started on the region. The current report presents the result of a two-day filed study and sampling for 30 thin-sections plus to several geochemical samples.
The area is 260 square kilometers located between south of Ardebil and east of Sarein. The lithology of the area composed of lagoonal deposits and volcanic rocks the unconformably overlay the Eocene andesite porphyry. Three diatomite bearing sections were studied. The silica grade of these layers is about 60%. The diatoms show diversity in forms including circular, colony and spindle. The large extent and purity and uniformity of diatomite, close distant to the main roads are of positive values of the region. Negative point for the region is the existence of freshwater limestone beds above the diatomite layers that are up to 15m thick.