Morphologic characteristics of aeolian deposits and erosive winds in Sistan plain

Document Type : Original Article

Authors

1 Research Instructor, Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran

2 Senior Expert, Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran

3 Assistant Professor, Sistan Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Zabol, Iran

Abstract

Shifting aeolian dunes damage to infrastructure in Sistan plain.  Accordingly, distribution, morphology and fixed and unfixed status of sand dunes in erosive corridors were surveyed by using satellite images and field investigation. Mean wind velocity, average seasonal and annual sand drift potential, resultant drift direction, resultant drift potential and unidirectional index (RDP/DP) were calculated using hourly wind speed and direction data in six meteorological stations around Sistan plain.  In addition, temporal and spatial variation of wind energy were mapped using Kriging geostatistical method. The results show that activity of sand dunes matched wind of 120 days which lifted sediment from the dry beds of Hamoun Lake into 4 erosive corridors based on topography which forms Registan sand seas in the southwest Afghanistan. The types of dunes are Barchans, transvers and sheet which is formed by unidirectional wind. The DP decreased from northwest to southeast of region and the value of drift potential in Zabol station was calculated 2516 vector unit that it is one of the highest values in inland deserts of the world.

Keywords