华北南部晚古生代陆表海盆地层序地层格架与海平面变化

陆表海盆地与边缘海盆地的区域地质条件具有根本性差异,其层序地层格架必然不同。研究表明,华北晚古生代陆表海盆地极平缓的地势难以形成大范围的侵蚀不整合,高频海平面变化和突发性的海侵事件是层序形成的主导因素。陆表海盆地含煤层序具有二元结构,即"海侵体系域—高水位体系域"的层序模式。

SEQUENCE STRATIGRAPHIC FRAMEWORK AND SEA-LEVEL CHANGES IN THE LATE PALAEOZOIC EPICONTINENTAL BASIN IN NORTHERN CHINA

The sequence stratigraphic framework of an epicontinental basin differs from that of amarginal basin because of the differences in regional settings in the two kinds of basins.The research results in the present paper show that the main factors controlling the formation of the sequences in the Late Palaeozoic epicontinental basin in northern China are high-frequency sea-level changes and episodic transgressive events, because the gentle slope of the basin made it difficult to form basin-wide erosional unconformity. The coalbearing sequences in the epicontinental basin are of binary configuration, i. e., the sequence model of "transgressive systems tract-highstand systems tract".