武当地区武当岩群变火山岩原岩性质及其构造环境研究

Original Petrology and Tectonic Setting of Meta-Volcanic Rocks in Wudang Rock Group

武当岩群中的变火山岩类经历了海水蚀变和区域变质的改造,其岩石学特征和化学成分发生了较大变化。不活动组分的研究表明,武当岩群中的变基性火山岩属拉斑玄武岩浆系列,原岩为玄武岩类;变酸性火山岩属钙碱性岩浆系列,原岩为流纹岩类,后者是前者结晶分异的产物。它们的地球化学特征具岛弧火山岩的性质,形成于岛弧环境。

The meta-volcanic rocks in the Wudang Rock Group have undergone alteration and regional metamorphism, so these rocks have been changed in petrographic features and chemical compositions. Studies of immobile elements in the rocks show that these meta-volcanic rocks were originally tholeiite and ryhyolite, and have geochemical characteristics of island arc volcanic rocks, formed in the island arc setting.