Study of Serpentinized Ultramafic Rocks of Bela Ophiolite, Balochistan, Pakistan

Abstract

Mineralogical and petrological study of ultramafic rocks of Bela Ophiolite of Cretaceous age revealed serpentinization after harzburgite. It is further evident on SiO2/MgO vs. Al2O3, molar ratio Si/Mg+Fe vs. LOI and MgO-SiO2-LOI diagrams. The XRD analysis also showed occurrence of olivine, different members of pyroxene and serpentine groups. The three polymorphous of serpentines can be distinguished on (Fe2++ Mg2+)/(Fe3++A13+) vs. H2O diagram, reflecting thermal regime in the study area.