B. H. Emraninasab et al. 315HST system tracts, separated from each other by MFS. Sartakht formation rocks in Bakhshi section are deposited in a low-angle homoclinal ramp, mostly in the inner ramp, located in the south of Paleotethys Ocean. The depositional sequence identified in Sartakht formation points to the age of middle Permian, conforming to middle Absaroka II supersequence. The upper erosional boundary between Sartakht and Hermez formations conforms to the global-scale sea level fall.

The upstream water catchments are the main source providing sediments in rivers and sedimentary basins. The balance between the erosion phenomenon and the amount of sediment entering into the basin relies on the geometrical specifications and the morphology of the river along the water catchment direction and the amount and type of the sediments. The sedimentary feed of rivers and basins are changed for the sake of natural factors or human disturbances. The river and basin react against this change in that their shape, morphology, plan and profile get changed due to the increase or decrease of the input sediment into the basin. It is essential to know the sediment amount produced by erodability and sedimentation of upstream basins and effects of projects and also to evaluate the amount of sedimentary load in base studies, civil projects, optimizing rivers and dam construction studies specially calculating the amount of sediment amount entering into the dams' reservoirs in order to take engineering decisions and related alternatives. Sediment Weight Model and PSIAC Experimental Model are recognized as two common methods calculating the amount of the produced sediment caused by erosion applied in this research. Holistically, these methods have been used and compared. Although the results are almost close to one anoth-* Corresponding author. A. Alijani et al. 693 er, more sediment load has been produced in PSIAC method. As more affective parameters are used to cause erosion and produce sediment in PSIAC experimental model, it is recommended to refer to the results of this method because they are closer to reality.

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A multidisciplinary study of the sedimentology, geochemistry and mineralogy has been conducted to understand the linkage between marsh and alluvial sediments and also their potential sources in Eynak marsh, North of Iran. The influence of the upstream potential sources on recent sediment geochemistry has been discussed based on geochemical, sedimentological and mineralogical results. A spatial grain size distribution study was carried out to investigate the hydrodynamic and deposition system of the marsh. So, the surficial sediment sampling was carried out to describe the sedimentological parameters and elemental geochemistry of sediments in Eynak marsh. Mineralogical complexes are mainly made up of felsic minerals such as quartz, calcite, feldspar, pyrite, mica, and clay minerals (in very low values) indicated by high amounts of Al, Ca, and Ni. As expected, the mineralogy of sediments is controlled mainly by the rock formations. Also sediment textures are controlled by the hydrodynamic condition in the marsh. So its distribution has been influenced by distance from the entrance sediments to Eynak marsh. The results showed that there are no enrichments related to fine grain sediment distributions. An association of Al with the trace elements such as Sc, Y, La, Ce, and Zr indicates that their distributions are mainly controlled by the felsic rocks in the upstream. On the other side, due to the waste water entrance to the marsh, Ni and Pb concentration could be under the effects of anthropogenic activities around the marsh. Results represented high values for Mn concentration (min 462, max 1784 and average 1037 ppm) and it showed a significant correlation with Ca, Sr, and Mg. A redox habitat and constantly calm hydrodynamic circumstance in the study area, likely cause high concentration of Ca, Sr, and Mg, and Mn. And they are representing negative correlations with some elements such as Al, Be, Fe, K, and Na.

Provenance and tectonic setting of the Late Lower Cretaceous (Albian) sandstones in SW Iran have been interpreted on the basis of geochemistry (major and trace elements) of 35 samples from Iranian offshore oil fields (Soroosh, Nowrooz, Foroozan and Hendijan). Geochemically, trace-element concentrations, such as La, Th, Sc and Zr, and ratios, such as La/Sc, Th/Sc, La/Co, and Th/Co, of sandstones from Kazhdumi Formation at four localities indicate that they were derived from felsic source rocks and deposited in a passive continental margin. Most major and trace element contents of Kazhdumi sandstones are generally similar to upper continental crust (UCC) values. However, some samples are depleted in major and trace elements (such as K2O, Na2O, Sr and Ba) relative to UCC, which is mainly due to absence or smaller amount of Na-rich plagioclase and K-feldspar and also paucity of clay minerals, which is possibly due to intense weathering and recycling. Enrichments in Zr, negative Sr anomalies and Th/U ratios higher than 4 for Kazhdumi sandstones are further evidence for recycled sources. The study of paleoweathering conditions based on chemical index of weathering (CIW) indicates a moderate to intense weathering of first cycle sediments, or it may alternatively reflect recycling under semi-arid to semi-humid climate conditions in Kazhdumi sandstones. The results of this study suggest that the main source for the Kazhdumi sandstones is likely located in uplifted shoulders of a rifted basin (Neo-Tethys) in its post-rift stage (Arabian basement).