摘要
依据在原划武当岩群中获得的 1 6 86± 4 5Ma (锆石U -Pb)同位素测年资料 ,结合岩石学、岩石地球化学及区域地层对比 ,从中解体出姚坪岩组。通过岩石学、岩石地球化学、构造特征、变质变形特征研究及形成环境探讨认为 :南秦岭凤凰山元古代武当岩群 (包括姚坪岩组、杨坪岩组 )变质火山岩系为古—中元古代时期多岛洋构造环境过渡基底建造 ;耀岭河岩组浅变质火山岩为本区Rodina事件的产物。该成果对南秦岭构造基底的组成、发展、演化研究具有重要意义。
Studies of lithology, lithochemistry, regionally stratigraphic correlation and the isotopic dating (zircon U Pb,1686±±45Ma), which is obtained from the original Wudang Rock Group have separated out the Yaoping Formation. Discussion and studies of lithology, lithogeochemistry, structures, reformation, metamorphism and forming environment have denoted that the metamorphosed igneous rock system of the paleo middle Proterozoic Wudang Rock Group (including the Yaoping Formation and the Yangping rock Formation) in Fenghuangshan area of Southern Qinling is a transitional basement formation under a multiple island ocean structural setting in the early middle Proterozoic era; the shallow metamorphosed igneous rock of the Yaolinghe rock formation was the result of the Rodina event in this area. This conclusion is important for the studies of the formation, development and evolvement of the structural basement in Southern Qinling.
出处
《陕西地质》
2002年第2期9-19,共11页
Geology of Shaanxi
基金
项目编号 :QD970 3
马池幅
汉王城幅
瓦房店幅 1:5万区调联测。
关键词
元古代
凤凰山地区
构造基底
武当岩群
姚坪岩组
杨坪岩组
耀岭河岩组
锆石U-Pb同位素测年资料
southern Qinling, Fenghuangshan area, structural basement, the Wudang Rock Group, the Yaoping rock Formation, the Yangping Rock Formation, the Yaolinghe Rock Formation