关键词: 小江断裂, 盆地, 断层活动

Abstract: Along the middle segment of the Xiaojinag fault zone 21 basins of different scales have developed since Cenozoic. They have 4 different stages of evolution,i.e. the Eocene Oligocene,the Pliocene-early Pleistocene,the middle Pleistocene and the late Pleistocene Holocene stages. Among them,the Pliocene-early Pleistocene stage was the period of great prosperity of the basins. According to the duration time of the development of the basins,they can be classified into inherited basin,staged basin,rejuvenated basin and new born basin. The basins can be assigned to depressed and non-depressed origin. The Eocene Oligocene stage was dominated by non-depressed basins,the Pliocene-early Pleistocene stage was dominated by both depressed and non-depressed basins,while the stage after the middle Pleistocene was dominated by depressed basins. The depressed basins can further be divided into thrust type,graben-semigraben type and pull-apart type basins. Based on the analysis of the formation mechanism,plane distribtuion and the type of deposition of the basins,the authors have discussed the characteristics of the regional crustal movement in the different periods of Cenozoic along the southeastern margin of Qinghai Tibet Plateau and in Sichuan-Yunnan region.

Key words: Xiaojiang fault, Basin, Faulting