Trace element partition between two pyroxenes and the host lava

Abstract

Partition coefficients for +1, +2, +3 and +4 valent trace ions between alkaline olivine basalt lava and the coexisting ortho- and clinopyroxene phenocrysts from Takashima, North Kyushu, Japan, have been determined by neutron activation analysis. Substitution of trace elements in crystal lattice sites is proposed for the mechanism of trace element partition by examining the relation between measured partition coefficients and ionic radius and ionic charge.