منشایابی رسوبات آبی حوضه ورتوران قزوین با روش انگشت نگاری ترکیبی

Determining the relative contribution of sediment sources is the first step in planning for soil conservation programs. Due to many problems of traditional methods for determining the contribution of sediment sources, fingerprinting technique have attracted the researchers as an appropriate alternative. The main purpose of this study was to determine the relative contribution and importance of sediment sources of Vartavan catchment using composite fingerprinting technique. Therefore, after preparing the precise lithological map of catchment, 66 samples of sediment sources and 9 samples of sediments were collected. Particle size distribution, mineral and element content of samples were determined. Then nine lithological units were classified to three sediment sources (volcanic, calcareous and clastics) using cluster analysis. Three tracer including Cd, Pb and calcite were determined as the optimum tracers combination using discriminant function analysis. The output of multivariate mixing model showed that the contribution of sedimentary (red mudstone, red sandstone, black shale), calcareous (shale limestone, orbitolina limestone and plagioclase limestone) and volcanic sources (dark tuff, andesite) in Kaman subcatchment were 63.4, 25.8 and 10.8 percent and in Mushaghin subcatchment were 36.2, 45.9 and 17.9 percent, and in whole output were equal to 47.6, 37.4 and 15.1 percent respectively. But the relative importance of sediment sources that is an index that the effect of source area is removed, is as sedimentary > calcareous > volcanic in subcatchments and final outlet.