The Tibetan Plateau is the largest orogenic belt on the Earth with high topography and thickened crust, which extends over 2,000 km from the Himalayas to central Asia (England & Houseman, 1986). It is generally believed that the growth of the Tibetan Plateau is the consequence of the continental collision between the Indian and Eurasia plates since the Cenozoic (Tapponnier et al., 2001). However, how the Tibetan Plateau uplifted to its present high topography is a subject of debate (Spicer et al., 2021).Significant attention has been given to the mechanism of crustal thickening and outward growth of the high terrain along the northeastern (NE) Tibetan Plateau (Yin & Harrison, 2000;Zheng et al., 2017), which is the leading edge of the plateau expansion. NE Tibet is composed of several blocks, including the SGT, Kunlun-West Qinling Terrane (KL-WQL), and Qilian orogen from the south to north, which are separated by several major active faults including the KL-WQL, South Qilian Suture, and Haiyuan Fault (HYF; Figure 1). To the east and northeast, NE Tibet is surrounded by the relatively stable Alax and Ordos blocks. On the surface, NE Tibet is generally bounded by the Haiyuan-Liupanshan Fault system to the northeast and the north Qilian frontal thrust (NQFT) to the north (Gao et al., 2013, Figure 1). However, recent surface geological investigations have found that the Tibetan Plateau continues to grow northeastward across the Hexi Corridor, as evidenced by the uplift of Longshou Shan and Heli Shan (Zhang et al., 2017;Zheng et al., 2013). Receiver function studies also reveal that the thickened crust (>50 km) is present across the Haiyuan and Liupanshan faults, suggesting the northeastward growth of the Tibetan plateau (Guo et al., 2015;Shen et al., 2017). Furthermore, recent studies reveal that rapid