Scholarlink

<p>Subduction-related Cu-(Au) deposits which represent giant geochemical anomalies of metals and S in the upper crust are commonly associated with arc magmas. However, the fundamental differences between barren and fertile magma producing these deposits still remain highly controversial. In this study, we report the chemical compositions of zircon and silicate melt inclusions (SMIs) from barren arc lavas at eastern Taiwan Island aiming to increase our knowledge on the factors that affect the mineralization potential of arc magma systems. The zircon U-Pb dating shows the magmatism occurred at ~0.7 Ma and the andesitic lava formed at ~900–950°C with a reduced magmatic environment. The plagioclase-hosted SMIs show an andesitic melt composition and variable Cu content features. The calculated H<sub>2</sub>O content of parental melt is ~3–4 wt.%. The evidence presented above suggests that oxidation state (<i>f</i>O<sub>2</sub>) and H<sub>2</sub>O content are probably the key controls of Cu-(Au) fertility of arc magmas. We interpret that a reduced and relatively dry magma may be a potential hinderance to cause the absence of porphyry Cu deposits at the eastern Taiwan Island.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

The factors affecting mineralization potential of arc magma: Insights from silicate melt inclusions and zircon composition of igneous lava at Eastern Taiwan Island

  • 期刊论文

  • 发表日期：

    2025年2月14日

查看全文
  • Jianping Li,
  • Shitao Zhang,
  • Gaobin Chu,
  • Huayong Chen

摘要

Subduction-related Cu-(Au) deposits which represent giant geochemical anomalies of metals and S in the upper crust are commonly associated with arc magmas. However, the fundamental differences between barren and fertile magma producing these deposits still remain highly controversial. In this study, we report the chemical compositions of zircon and silicate melt inclusions (SMIs) from barren arc lavas at eastern Taiwan Island aiming to increase our knowledge on the factors that affect the mineralization potential of arc magma systems. The zircon U-Pb dating shows the magmatism occurred at ~0.7 Ma and the andesitic lava formed at ~900–950°C with a reduced magmatic environment. The plagioclase-hosted SMIs show an andesitic melt composition and variable Cu content features. The calculated H2O content of parental melt is ~3–4 wt.%. The evidence presented above suggests that oxidation state (fO2) and H2O content are probably the key controls of Cu-(Au) fertility of arc magmas. We interpret that a reduced and relatively dry magma may be a potential hinderance to cause the absence of porphyry Cu deposits at the eastern Taiwan Island.