Petrographic and geochemical data of high alkaline basalts, Sisaket Terrain, NE Thailand

Abstract

This data article presents mineralogical and geochemical data of high alkaline basalts in Sisaket province, the southern part of Khorat Plateau, NE Thailand. Under the polarized light microscope, the photomicrographs divided the basalts into olivine basalt and alkaline basalt with four textures: aphanitic, porphyritic, vesicular, and diabase. These basaltic rocks comprise olivine microphenocrysts associated with labradorite-anorthite (An66-94), clinopyroxene, opaque minerals groundmass. In addition, nepheline is only found in alkaline basalt as groundmass. Major oxides (Na2O+K2O and SiO2) suggest that Sisaket basalts are basalt, basanite, trachy basalt, and basaltic trachy-andesite. High ratio Nb/Y and low Zr/Ti classify these basalts as alkaline basalt and basanite.

Keywords

• Geochemistry
• Petrology
• Cenozoic basalt
• Trace elements
• Rare earth elements
• ICP-MS