祁连山区燕山期构造体系的特征

Caracteristics of Structure Systems at Yanshan Stage in Qilianshan Region

白垩纪末期的燕山运动席卷全国,这场运动使祁吕贺兰山字型发育成熟。自从喜马拉雅运动以来,出现的新的构造体系的隆起带或坳陷带不整合的斜接或反接在该区古老构造体系之上;而印支运动又使山字型前弧西翼褶带与西翼反射弧褶带普遍的不整合在祁连运动产生的褶皱之上。笔者通过编制燕山期构造体系图和6张该区晚古生代的岩相古地理图,追溯了该区从祁连期至燕山期形变与形成的历史,结合模拟实验,从而讨论了祁连山区从泥盆纪至白垩纪构造体系的发展变化。

The Yanshan movement occurred at the end of Cretaeens swept across the whole China. This movement gave rise to full-growth of the Qilianshan-Luliangshan-Helanshan ∈ structure,Since Himalayan movement, the new structural systems of upheaval belt or depression belt came to pass in juxtaposition or in transposition on the older strueturai systems, moreover Indosinian movement in turn led to both the west-wing fold belt and the reflexarc fold belt of the ∈ front arc uncomformably overlay on the folds produced by the Qilianshan movement. By means of drawing up both map of structural system of Yanshan stage and six lithofacies paleogeographic maps of Late Paleozoic age, the history of both the deformation and the formation from Qilianshan stage to Yanshan stage in this area can be traced, and combined with model experiment, the evolutionary changes of the structural systems from Devonian to Cretaceous in the Qilianshan region are then discussed.