CHEMICAL VARIATIONS AMONG L-GROUP CHONDRITES I. THE AIR,APT AND TOURINNES-LA-GROSSE (L6) CHONDRITES

Petrographic, mineralogical and bulk chemical data are presented for three of approximately 25 L-group chondrites with which we are attempting to define and interpret major element chemical variations in the L-group. Two of these unbrecciated L6 chondrites - Aïr and Apt - have olivine and feldspar characteristics that testify to shock pressures of approximately 240–260 kb; they contain sparse veins and pockets of glass. The third, Tourinnes-la-Grosse, experienced a lower shock pressure and lacks such evidence of melting.