云开地区两个隐蔽不整合界面的发现

云开变质岩区隐蔽有两个不整合面，其分别代表华夏运动与晋宁运动。上隐蔽不整合面处在海西期中－深层次的绿片岩相滑脱拆离带中，上、下岩系构成非递增变质相系；下隐蔽不整合面处在晋宁期深层次的角门岩相沿脱拆离带中，上、下岩系构成递增变质相系。以原始露头、生物化石和同位素年龄等资料建立的云开变质岩地层往依次为早元古代天堂山群、中一晚元古代云开群、寒武纪八村群、奥陶系及志留系。

THE DISCOVERY OF TWO BLIND UNCONFORMITIES IN YUNKAI REGION

There are two blind unconformities which represent respectively Cathaysianmovement and Jinning movement in Yunkai region. The upper blind unconformity is located in the detachment fault zone within greenschist factes which was formed in Hercynian period and there are non-progressive metamorphic factes with in the rocks of the upper and lower formations. The lower blind unconformity is located in the detachment fault zone within amphibolite factes forming in Jinning period and there is progressive metamorphic factes within the rocks of the upper and lower formations. The metamorphic rocks stratigraphy column established by field crops and biologic fussil and isotopic age information suggestthat there are Tiantangshan Group of lower Proterozoic. Yunkai Group of upper-midProterozoic, Cambrian Bachuan Group, Ordovician and Silurian.