摘要
可可西里一巴颜喀拉活动型三叠系,与相邻古陆上的稳定型三叠系分布区,构成特提期三叠纪海域。盆地由于基底性质和地质构造背景以及演化过程的差异而具多级性。本文将该盆地作为一级沉积盆地下分四个二级沉积盆地和一个构造带,对其形成机理及演化特征分析研究,指出沉积盆地是古北特提斯裂谷型海槽经过晚二叠世闭合期后形成的活动型海盆。海盆形成于早三叠世早期,到晚三叠世晚期和侏罗纪早期才全部闭合成造山带,经历了沉降—沉积期、隆升—闭合期和闭合期后不同的发展阶段,具有鲜明的演化特征。
The Hoh Xil-Bayan Har sedimentary basin where the active Triassic widely dis-tributed and adjacent paleocontinent where the stable Triassic spreaded had been TriassicTethys sea area. The basin is characterized bymulti-grades owing to the differences of base-mental features, geological structure settings and evolutional process. It, therefore, can beconsidered as a Ⅰ-grade sedimentary basin and divided into four Ⅱ-grade sedimentary basinsand a tectonic belt. Based on the research of forming mechanisms and evolutional character-istics, the author suggest that the sedimentary basin is an active sea-basin formed by the ancient Northern tethys rift trough through the Late Permian closing period. The sea-basinoriginated in the beginning of Triassic was not closed to forman orogenetic belt until the endof Late Triassic or Early Jurassic, passing through the distinct evolutional stages, i. e. de-pression-sedimentary, rising-closing and postclosing stages.
