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In the Zagros fold-thrust belt, the Fars region is affected by the basement left-lateral strike-slip faults such as the Nezamabad, Razak, and Hendurabi faults which these faults have affected on the folding system of this area and the effect of these faults activity is one of the factors in the folding diversity. Also, the Fars region anticlines are very important in the Zagros fold-thrust belt, due to their huge gas reserves in the Permian‒Triassic carbonate sediments. The Hendurabi faults have major effects on folding style base on changes of the folding geometry. For more analysis, when the effective stress and deformation value is different, the type of fold has been changed in different parts of fold. This case may be created by cropping out of the salt domes, activities of main active faults and other structural elements. The studied area is a special structural feature in the Zagros fold-thrust belt that is shown the effects of the strike slip faults on the folding geometry. In the study area, close fold type in all parts has shown the study anticline affected by the special may be from deformation of the Razak and Hendurabi sinistral strike-slip faults. [ABSTRACT FROM AUTHOR]

Quaternary sediments of the Haji Arab River catchment located in Qazvin Plain, northwestern Iran, were studied in terms of sedimentology and geochemistry to determine the sedimentary environment and rock weathering. Discrimination diagrams show that the source rock of these sediments is granite and their tectonic setting is the active continental margin. These rocks show a negative Eu anomaly and a high ratio of light rare earth elements to heavy rare earth elements, suggesting that these sediments are originated due to the weathering of felsic rocks. Regarding the descending trend of chemical index of weathering, chemical index of alteration values, and the increase in coarse-grained particles, it was concluded that the sediments from the depth of 6 to 2.6 m formed under arid and high-energy conditions; however, this trend for sediments from 2.6 m depth to surface changes slightly toward semi-humid up to semiarid climate. Hence, it can be stated that the conditions of sedimentation environments in the Haji Arab basin are not constant at least in the Upper Holocene (Schmidt et al. in Holocene, 2011. https://doi.org/10.1177/0959683610385961) and this has led to changes in river sedimentation. These results indicate the changes in river regime conditions probably because of the changes in weather conditions during the Quaternary. [ABSTRACT FROM AUTHOR]

The study area is the Southern Caspian Sea. Three rivers, Chalous, Sardabroud and Namak Abroud, are effective in this area. Sediment loads carried by these three rivers are the source of environmental pollution in this area's seabed sediments. To identify environmental pollution in this research, a total amount of 80 samples were collected from sediment of the sea and the rivers. By measuring the amount of As, Cd, Co, Cr, Cu, Ni, Pb and Zn in these sediments, one can determine the pollution pattern in this area by calculating environmental indicators such as: Geoaccumulation Index, Enrichment Factor, Contamination Factor and Pollution Load Index. Granulometry experiments show that sedimentary facies are divided into two main groups: sand and mud. The amount of Geoaccumulation Index is unpolluted. Enrichment Factor of river and shallow water sediments, the amount of As, Cd, Pb, Zn is in the high to medium category and the amount of Co, Cr, Cu and Ni is in the low category. Contamination Factor shows that river and shallow water sediments are very high to low ranking. Pollution Load Index is showing heavy metal contamination in the river and shallow water sediments. Statistical studies reveal the relationship between the pollution indicators and the amount of elements more effectively. The concentration of heavy metals in river sediments is more than in marine sediments due to the use of pesticides and chemical fertilizers in agricultural lands. The results of contamination indicate their anthropogenic origin and the lithological does not in the production of environmental pollution. [ABSTRACT FROM AUTHOR]

Kashkan Formation is located in Merk watershed in the southeast of Kermanshah, Iran, at a distance of 35 km. The age of the studied formation ranges from upper Paleocene to middle Eocene. This formation is located between two shallow-environment carbonated formations (Teleh-Zang Formation at the bottom and Shahbazan Formation at the top). While there is no Teleh-Zang Formation (like the study area), Kashkan Formation lies above Amiran Formation. Regarded also as a forest, this formation includes clay, silt and sandstone. Field and microscopic studies reflect two sandstone (chert arenite and lithic arenite) and siltstone petrofacies. In this study, seven lithofacies (Gm, Sm, St, Sr, Fm, Fl and P) and four architectural elements (CH, CS, FF and OF) were identified in two sections. The detailed grain-size analysis was used as a vital sedimentological tool to unravel the hydrodynamic conditions, mode of transportation and deposition of detrital sediments. Twenty samples from Kashkan Formation were investigated. Parameters of grain statistics and bivariate analysis were used to reveal the depositional processes, sedimentation mechanisms, hydrodynamic energy conditions and to discriminate different depositional environments. The results showed that the depositional environment of Kashkan Formation is braided river with sedimentary load of sand and silt classified as Bijou Creek Type. [ABSTRACT FROM AUTHOR]