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对胶东谭格庄地区一地质剖面进行了详细野外观察和锆石SHRIMP年代学研究。剖面主要是由奥长花岗质片麻岩和斜长角闪岩组成,两者互层产出并一起发生褶皱变形,在强变形域两者完全平行化。所以,在强变形地区,不同成分岩性的薄层状互层产出不能作为变质沉积岩的识别标志。奥长花岗质片麻岩(S1105)形成于2496±10Ma,遭受了古元古代早期和晚期变质。两个斜长角闪岩样品(S1238和S0812)都只发育变质锆石,年龄分别为1842±3Ma和1833±13Ma。该剖面岩石记录的两期变质作用在胶东地区具有普遍意义。结合前人研究,作者指出该地区太古宙末存在区域性变质深熔作用,早期地壳受到了强烈的再造;古元古代末的变质作用具有带状分布特点,与造山作用有关。
A detailed geological observation and zircon SHRIMP geochronology of a geologic profile in the Tangezhuang area, Jiaodong were carried out. The section is mainly composed of palaeogene gneisses and amphibolite, both of which are interbedded and fold along with each other, and are fully parallel in the strong deformation zone. Therefore, in strongly deformed areas, the output of thin-bedded interbeds with different lithologies can not be used as the identification mark of metamorphic sedimentary rocks. The Neoproterozoic gneiss (S1105) was formed at 2496 ± 10Ma and suffered early and late Paleoproterozoic metamorphism. Both amphibolite samples (S1238 and S0812) developed only metamorphic zircons, with ages of 1842 ± 3Ma and 1833 ± 13Ma, respectively. The two metamorphism recorded by this section of rock have a universal significance in Jiaodong area. Combined with the previous studies, the author points out that the Late Archean in the area had regional metamorphism and deep melting, and the crust was strongly rebuilt in early stage. The metamorphism of late Paleoproterozoic has belt-like distribution, which is related to the orogenic function.