土壤科学与植物健康杂志

Routing and Geochemical Properties of Clastic Sediments in Southwestern Iran

Amir Jokar*, Nader Kohansal Ghadimvand, Davood Jahani and Mahdi Mashal

The Khuzestan plain is located in the southwest of Iran in the Khuzestan province and southwest of the Zagros Mountains. It is a part of the Arabian platform and has a completely sedimentary rock lithology. As one of the most important oil regions of Iran and the Middle East, the plain is of great importance in the geochemical and environmental studies. These studies aim to examine 276 sedimentary samples from different parts of this plain. Initially, the basic sedimentary properties of the samples are studied, especially in terms of grading and particle size changes. Then, the detailed geochemical analysis of the sediments is performed to determine all sediment properties, including the routing, paleoclimatology, and environmental characteristics of the sediments. The results of granulometric studies indicate that the sediments are mainly of silt and clay dimensions, and the particles of sand and gravel dimensions are less frequent in the study areas. Investigating the geochemical properties of the sediments indicates that the most frequent constituent oxides in the study area are Cao, SiO₂ and Al₂O₃, respectively. Also, according to the studies, the most frequent sub-elements in the study areas are Ti, Zr, V, Ce and La, respectively. The classification of the sediments based on the geochemical indicators shows that the sediments are mainly in the range of greywacke and ferruginous shales. In addition, the paleo- climatological studies indicate the arid to semi-arid climate conditions in the sediment source area. The tectonic setting studies in the area based on the geochemical properties of the sediments indicate the tectonic settings of continental island arc and active continental margin. Also, the routing of the sediments indicates the mainly felsic and sometimes mafic source of the mentioned sediments. The study of environmental contamination in the study areas indicates that elements Ni, Cr and Zn are the most frequent heavy metals in the sediments.