QUALITATIVE METHODS FOR DETECTING THE SEDIMENT SOURCES BY GRAIN SIZE DISTRIBUTION AND X-RAY DIFFRACTION

Abstract

The sources of sediment deposited in Sengguruh and Sutami reservoirs are detected by qualitative analysis of grain size distribution and mineral composition resulted from x-ray powder diffraction (XRD). Grain size distribution of sediment in Sengguruh reservoir shows that Lesti sub-basin contributes higher percentage of sand particles than Brantas sub-basin. The most dominant minerals in Sengguruh reservoir are Feldspar and Carbonate (Calcite). In Sutami reservoir, the most dominant minerals are Feldspar, Mica and Chlorite. The difference of mineral composition both of reservoirs indicates the increasing of sedimentation from Metro-sub-basin. Now, it should be considered while it was neglected in the past. Finally, the proposed method is applicable to assess sub-basins contribution of sediment origin and to evaluate the existing sedimentation countermeasures.