منشايابي رسوبات بادي منطقه رفسنجان

Source Studying of Eolian Sediments in Rafsanjan Region

Prevention of sediment movement in the taking area is a fundamental basic task. For source studying of Rafsanjan eolian sediments, step by step method (Ekhtesasi-Ahmadi et al.) was employed. This study is carried out in two stages: direction finding and location finding. For direction finding of taking sector, first through quesitionnaire Fill up informations on local winds were gathered. Then satellite images at two periods were compared through these images as well as field investigations, the erg morphological map was prepared. By studying wind regime and windrose drawing, the erosive winds were recognised. After recognition of taking sector (west and southwest sector), the location-finding phase was started. In this stage through geomorphological studying of taking sector and sampling into facies, the mineralogical and morphoscopical studies of sand dunes and taking sector sediments were done. At last with due attention to reasonings such as: the direction of Seif and Barkhan dunes (southwest-northeast), the settlement of Zibars in the west and southwest of erg, high intensity of energy for west and southwest winds, the existence of heavy minerals as Hematite and Amphibole in sediment samples, large median of samples (240 microns), the skewness of some samples towards coarse particles as well as low roundness factor (of taking sector samples), it was found that the sources of eolian sediments are close (<20 km) and inctude the followings: rangelands, abondoned farmlands and pistachio gardens on the east and southwest plains of Rafsanjan, the barelands or poorly covered grounds on the east pediments of Rafsanjan as well as beds of Shoor, Shahzadeh Abbas and Kabootarkhan rivers.