关键词: 柴达木, 阿尔金, 背斜, 变形特征

Abstract: The Cenozoic deformation in the NW Qaidam Basin is controlled by both the NE-directed thrusting and NEE-directed
sinistral strike-slipping. In this paper, we analyze the characteristics and mechanism of the Cenozoic deformation across the
Xianshuiquan anticline in the northern end of the Yinxiong Range in the western Qaidam Basin based on field investigation,
borehole logging, and 3D high-resolution seismic data. The results show that the Xianshuiquan anticline is largely controlled by
NEE-directed basement-involved dextral thrust faults since the late Miocene with intense deformation occurring in Pleistocene.
According to the different deformation patterns, we divide the Xianshuiquan anticline into the northern and the southern parts.
The southern part is slightly influenced by the Altyn Tagh Fault system and is characterized by the development of NNW-trending
secondary anticlines and NW-trending back-thrusts with small amount of horizontal shortening. The northern part is greatly
affected by the Altyn Tagh Fault system and is characterized by NWW-trending sub-anticlines and back-thrusts with much larger
amount of shortening. Our results support that the Qaidam basin is a compression-dominated basin, and the influence of the
sinistral strike-slip Altyn Tagh Fault system on its deformation is only confined within a limited area in the Cenozoic.

Key words: Qaidam, Altyn Tagh, anticline, deformation characteristics