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朝鲜平南盆地翁津地区发育中元古代黄海群和同时期(称之为瓮津期)花岗岩,花岗岩体侵入于黄海群。本文采用锆石原位微区U-Pb定年技术,对黄海群中的酸性火山岩及花岗岩进行了年龄测试。获得的数据表明,黄海群中下部层位及上部层位的酸性火山岩分别在1235±5Ma和1203±7Ma喷发,由此说明黄海群的沉积时代应为中元古代,而不是传统上认为的古元古代;两个翁津期花岗岩体(翁津和黄衣山岩体)的侵位年龄分别为1251±22Ma和1248±13Ma,为中元古代花岗质岩浆活动的产物。上述1251~1203Ma年龄的获得,表明朝鲜半岛发育中元古代岩浆作用,从而明确朝鲜黄海裂谷与华北东缘裂谷在时间上具有同期性,同时也表明中国华北与朝鲜在中元古代具有类似的发展历史。
In the Wengjin area of the Pingnan basin in North Korea, the Mesozoic Huanghai Group and the granite in the same period (called Ongjin period) were developed. The granite invaded the Huanghai Group. In this paper, the in-situ zircon U-Pb dating technique was used to test the age of acidic volcanics and granites in the Huanghai Group. The obtained data indicate that the acidic volcanic rocks in the middle and lower strata of the Huanghai Group and the upper strata erupt respectively at 1235 ± 5Ma and 1203 ± 7Ma, indicating that the depositional age of the Yellow Sea Group should be the Proterozoic, rather than the traditionally considered ancient Proterozoic. The emplacement ages of the two Wengjin granites (Wengjin and Huangyi rocks) are 1251 ± 22Ma and 1248 ± 13Ma respectively, which are the products of the Mesoproterozoic granitic magmatism. The above 1251-1203 Ma ages indicate that the Paleoproterozoic magmatism was developed in the Korean Peninsula so as to make it clear that the North Sea rift in North Korea has the same period of time as the eastern North China Rift and that North China and North Korea in North China had a similar The history of development.