Sediment Fingerprinting in the Gheshlagh Dam Watershed, Sanandaj, Using the Geochemical Method based on the Two-Stage Statistical Analyses

Determination of the role of each lithological unit in sediment production is an important priority of watershed management. The geochemical method provides the means to determine the origin of sediments in the Gheshlagh Dam, Sanandaj. Various lithological units were studied as sources of sediment deposited behind sediment-retaining structures. A total of 33 samples of sediment and sediment sources were collected and examined in the laboratory after sieving through a 62-micron sieve and identifying by instrument an ICP Initially, 9 sources of potassium, calcium, phosphorus, carbon, magnesium, chromium, sodium, cobalt, and nitrogen were used to determine the optimal composition of the tracers. Using the 2-stage analysis of variance and detection function, 3 elements, namely: cobalt, chromium, and calcium were selected as suitable tracers and entered the equation stepwise to determine the sources of sediment. The results indicated that the andesite lithological units with interlayers of shale (An / Sh) and microfossilized limestone (Lim) with 56.91 and 30.54%, respectively, had the highest share in the sediment production in the study area.