The abundance of iron and manganese were detected by using non-destructive X-ray Fluorescence (XRF) scanning technique. Continuous downcore measurements of element variations were performed in the ITRAX XRF Core Scanner Laboratory, Department of Geosciences, National Taiwan University. All U-channels were scanned by using the 3 kW Mo source and were analyzed at 30 kV/24 mA, 2 mm resolution with a exposure time of 30 s. The count value of each element was calculated from element peak areas of original XRF spectra by the Q-Spec software provided by COX Analytical Systems.