Crystal reaming during the assembly, maturation, and waning of an eleven-million-year crustal magma cycle: thermobarometry of the Aucanquilcha Volcanic Cluster

  title={Crystal reaming during the assembly, maturation, and waning of an eleven-million-year crustal magma cycle: thermobarometry of the Aucanquilcha Volcanic Cluster},
  author={Barry Alan Walker and Erik W. Klemetti and Anita L. Grunder and John H. Dilles and F.J. Iii Tepley and D. Giles},
  journal={Contributions to Mineralogy and Petrology},
Phenocryst assemblages of lavas from the long-lived Aucanquilcha Volcanic Cluster (AVC) have been probed to assess pressure and temperature conditions of pre-eruptive arc magmas. Andesite to dacite lavas of the AVC erupted throughout an 11-million-year, arc magmatic cycle in the central Andes in northern Chile. Phases targeted for thermobarometry include amphibole, plagioclase, pyroxenes, and Fe–Ti oxides. Overall, crystallization is documented over 1–7.5 kbar (~25 km) of pressure and ~680–1… 
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