Minor- and trace-element zoning in plagioclase: implications for magma chamber processes at Parinacota volcano, northern Chile

  title={Minor- and trace-element zoning in plagioclase: implications for magma chamber processes at Parinacota volcano, northern Chile},
  author={C. Ginibre and G. W{\"o}rner and A. Kronz},
  journal={Contributions to Mineralogy and Petrology},
Abstract. Textural and compositional zoning in plagioclase phenocrysts in a sample from Parinacota volcano (Chile) was investigated using backscattered electron images and electron microprobe analysis of major and trace elements. Large (2 mm) oscillatory zoned crystals (type I) with resorption surfaces of moderate An discontinuities (⩽10% An) and decreasing trace-element contents (Sr, Mg, Ti) towards the rim reflect melt differentiation and turbulent convection in the main magma body. Early… Expand
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