Chemical Elements Analysis of Arjuno-Welirang Igneous Rocks

Abstract

Mount of Arjuno-Welirang has a geological structure consisting of volcanic breccias, lava, tuff and tuff breccias. This study aims to determine the chemical element content of the igneous rocks constructed on Mount Arjuno-Welirang. X-ray fluorescence (XRF) analysis of 7 samples showed the presence of Al, Si, P, K, Ca, Ti, V, Cr, Mn, Fe, Cu, Zn, Sr, Ba, Eu, and Re. The dominant elements (Wt% >10%) from high concentrations are Si, Al, Ca, and Fe. In addition, we also found Rare Earth Element (REE) Europium (Eu) content with an average of 0.23Wt%. SiO2 compound is larger than the Bromo-Semeru volcanic material, while K2O is larger than the Semeru volcanic material and smaller than Bromo. Meanwhile, the Fe2O3 compound is taller than that of Bromo-Semeru. Based on the Hutchinson formula, the depth of the magma source is determined in the range of ± 147.7 km to ± 225.1 km below the surface. Depth data also significantly affect several oxide compounds, such as K2O, V2O5, and ZnO, with correlations of .942**, − .747*, and − .936 **, respectively. The significant correlation shown is only the correlation with K2O, which offers a considerable correlation relationship with a positive trend.