中文摘要：

牛首山—罗山断裂带分隔了青藏高原东北缘和鄂尔多斯地块两大构造单元,是青藏高原东北缘最外缘的一条断裂带。通过断裂带内详细的构造变形测量,结合区域构造分析与筛分,获得新生代4期构造应力场。通过年代学的初步研究,提出牛首山—罗山断裂带新生代构造演化序列,即：始新世末—渐新世近N-S向挤压逆冲变形、中新世晚期—上新世NW SE向挤压与左行走滑活动、上新世末—中更新世NNE SSW向挤压与右行走滑活动、晚更新世以来近E-W向挤压与伸展构造。其中强烈的构造变形起始于中新世晚期,表明青藏高原东北缘的边界扩展在中新世晚期已经到达该断裂带。研究结果表明,牛首山—罗山断裂带在不同阶段的构造演化过程与印度欧亚大陆碰撞及青藏高原隆升过程密切相关,同时记录了青藏高原东北缘向外侧扩展和鄂尔多斯地块新生代构造转换的构造过程。

英文摘要：

The Niushou Shan Luo Shan fault zone is located in the outer edge of the northeastern Tibet Plateau and separates the northeast margin of the Tibet Plateau from the Ordos block.The structural features of the main faults and regional tectonic analysis indicate that the Niushou Shan Luo Shan fault zone may have undergone four stages of paleo-stress field in the Cenozoic.Combined with the geochronological information,the Cenozoic tectonic evolution may be constrained as follows： N-S compression and thrust in the Late Eocene Oligocene,NW SE compression and sinistral strike-slip in the Late Miocene to the Pliocene,NNE SSW compression and dextral strike-slip in the Late Pliocene to the Middle Pleistocene,and E-W compression and extension since the Late Pleistocene.The intensive structural deformation of the fault zone commenced at the Late Miocene,implying that the margin of the Northeastern Tibet Plateau had extended to the Niushou Shan Luo Shan fault zone at the time.Our study indicates that the Cenozoic tectonic evolution of the Niushou Shan Luo Shan fault zone was closely related to the Indian Eurasian continental collision and the Tibet Plateau uplifting,recording the northeastward growth of the Tibet Plateau and the Cenozoic tectonic transition of the Ordos block.