Variety of chemical compositions of amphiboles from eclogites in the Aktyuz area, northern Kyrgyz Tien-Shan

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　Amphiboles in the Aktyuz eclogites (Northern Kyrgyz Tien-Shan) have a variety of modes of occurrence and a wide range of compositions, including sodic-, sodic~calcic- and calcic-amphiboles. Amphibole inclusions in garnets are classified as glaucophane, Mg-taramite, Mg-katophorite, barroisite, and taramite, whereas amphibole inclusions within clinopyroxene are glaucophane, Mg-katophorite, barroisite, winchite, actinolite and edenite. Amphiboles replacing amphibole inclusions in garnet and clinopyroxene are classified as Fe-hornblende, actinolite, hastingsite and Fe-tschermakite. Amphibole inclusions within phengite are Mg-katophorite or Mg-taramite. Amphibole occurring as a constituent of amphibole + plagioclase aggregates after garnet has Mg-taramite composition. Amphibole in the matrix of the eclogites is zoned from Mg-taramite or taramite cores to Fe-pargasite/pargasite or Mg-hastingsite rims. Amphibole replacing porphyroblastic clinopyroxene is classified as barroisite, whereas amphibole replacing clinopyroxene as clinopyroxene + plagioclase symplectites is Mghastingsite. Porphyroblastic amphibole in retrograded eclogites is zoned from Mg-taramite cores to Mg-hastingsite or Fepargasite rims. Combining the petrography and chemistry of amphiboles in this study with previous studies, we conclude that the amphiboles formed at different stages of the metamorphic evolution of the Aktyuz eclogites.