Sedimentology and sedimentary geochemistry of Jazmurian playa

Document Type : Research Paper

Author

Abstract

Playa lakes are an important source for aeolian and dust storm sediments, because of their location in low land, arid and desert regions with strong wind systems and existence of fine and unconsolidated sediments. Jazmourian playa (Hamun Jazmourian) is an ephemeral lake with a large catchment has located in the Southeast of Iran. During the last 10 years, the playa was dried because of drought. In this study, 26 surface sediment samples were taken for sedimentology and sedimentary geochemistry analysis. Sieve for the samples, laser, calcimetry, mineralogy, morphoscopy, morphometry and chemical analyses have been done. Results show that the sediments with the size of silt and clay are dominated which are potentially suitably for wide distance and long time transportation. The most important minerals are calcite, quartz, feldspar and halite. Distributions of minerals in playa have a regular pattern. Montmorilonite, chlorite and Illite are the major clay minerals whereas Kaolinite is the minor one which is autogenic. Sedimentary geochemistry results show there are two main debris sources for the elements including igneous, ophiyolite omelange, and evaporate sediments. Elements Ca, Sr and Na mostly precipitate by chemical process in the playa. Because of morphology, climatology and sedimentology conditions, the Jazmuriyan playa is an important source of aeolian sediments and dust storm in the southeast of Iran and southearn Asia.              

Keywords