关键词: 东北地区, 晚古生界, 叠合盆地, 油气新层系

Abstract: Geotectonically, Tectonic setting in NE China during the Late Palaeozoic is traditionally referred to as a Variscan fold belt or orogenic belt. Therefore Late Palaeozoic rocks as a basement of Mesozoic-Cenozoic basins are regarded to be impossible for hydrocarbon exploration. Our recent studies indicate that a crust consolidating event occurred in the individual massifs in NE China in 500 Ma(±). The consolidated massifs amalgamated along the east margin of Daxing’anling Mountain, forming a composite massif as an independent evolution unit (we re-named Jiamusi-Xingmeng massif).The Late Palaeozoic Group is the first regional sedimentary cover on the composite massifs, which consists of marine sediments with abundant of well-preserved fossils. It is noteworthy that the Late Palaeozoic group is not subjected to the regional metamorphism and associated granites with large areas are not formed in Variscan, but Mesozoic time (220-180 Ma). Palaeogeographic features show that sediment setting of Late Carboniferous-Permian was a huge marine basin facing Paleo-Asian Ocean in south. The Mesozoic-Cenozoic lift basins represented by Songliao and Erlian basins are developed on the base of the Late Paleozoic marine sedimentary basin. Thus we suggest that the Late Palaeozoic sediments are not the metamorphosed basement in the Mesozoic-Cenozoic basins, they are superimposed basins. So the Late Palaeozoic group in NE China has tremendous potential for oil and gas resources, and should be an important new area for deep hydrocarbon exploration.

Key words: Northeastern China, Late Palaeozoic Group, superimposed basin, new area for hydrocarbon exploration