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我们回顾了奥斯陆(OSLO)地区最近的古地磁成果(有发表过的和未发表过的),包括沉积岩、菱长斑岩熔岩,互层玄武岩沉积层以及脉岩等资料。这些成果认为在裂谷带的南部和西部地区已经有前基阿玛(Kiaman)时代(即前石碳纪,距今300百万年)的大量岩浆作用。在前中生代时期主要的火成活动区看来是向北扩展了。因而,在晚石碳纪和或早二迭纪,火山活动似乎席卷整个 OSLO 地区.而在裂谷的北端(靠近布鲁蒙特(Erumurddal))熔岩流的喷出,发生在晚二迭纪.观察到构造变形晚于火山作用.很可能属于中生代时期。有晚于古生代时期.很可能在侏罗纪.看来至少有两次岩脉侵入脉动使奥斯陆(OSLO)区域受到了影响。
We review recent paleomagnetic achievements (published and unpublished) in the Oslo area, including sedimentary rocks, laponite lavas, interbedded basalts and veins. These results suggest that there is already a large amount of magmatic activity in the Kiaman era (formerly Carboniferous dating back 300 million years) in the southern and western parts of the rift zone. The major zones of pre-Mesoamerican events appeared to have expanded northward. Thus, during the Late Carboniferous and or Early Permian, volcanic activity appeared to swept the entire OSLO region, whereas lava flows at the northern tip of the rift (near Erumurddal) occurred during the Late Permian. It is observed that tectonic deformation is later than volcanism and is likely to belong to the Mesozoic period. Late in the Paleozoic period, most likely in the Jurassic, it appears that at least two diagenesis pulses have affected the Oslo area.