The Qingchuan Fault (QCF) is the main fault of the northeastern segment of the Longmenshan Fault zone (LMSFZ) on the eastern Tibetan Plateau boundary. The QCF accommodates ongoing deformation in the eastern Tibetan Plateau; however, its fault motion and potential seismic risk are still debated. This study combines a systematic analysis of deflected stream channels along the fault using 10-m digital elevation models with field investigations and measurements of the cosmogenic ¹⁰Be-derived erosion rates. The degree of channel deflection due to the interaction between strike-slip motion and channel growth processes is analyzed, followed by a quantitative extraction of the actual tectonic offsets and a calculation of the erosion rates. The long-term average strike-slip rates calculated from channel offsets range from 0.4 ± 0.1 to 1.7 ± 0.1 mm/a along the fault, with those in the southwestern section lower than those in the central section. Such differences may be attributed to slip partitioning of the northeastern extension of the Yingxiu–Beichuan Fault. In addition, analysis of stream longitudinal profiles and along-fault topographic variations illustrate that the small thrust component of the QCF decreases to the northeast, and a minor normal component exists at its northeastern end. The distributions of strike-slip and vertical-slip motions of the QCF indicate that fault slip of the central LMSFZ propagates to the northeast across the Minshan uplift and continues to slip along the QCF. Moreover, thrusting of the southern-central segment of the LMSFZ and dextral strike-slip faulting of the QCF may both accommodate complex deformation related to eastward expansion of the Tibetan Plateau. These findings have implications for constraining potential seismic hazards and understanding characteristics of the regional tectonic deformation.

青川断裂（QCF）是青藏高原东部边界龙门山断裂带（LMSFZ）东北段的主要断裂。QCF 适应青藏高原东部的持续变形；然而，它的断层运动和潜在的地震风险仍然存在争议。本研究结合了使用 10 米数字高程模型对沿断层偏转的河流通道进行的系统分析，以及对宇宙成因^{10 的}实地调查和测量。Be 衍生的侵蚀率。分析了由于走滑运动和通道生长过程之间的相互作用而导致的通道偏转程度，然后定量提取实际构造偏移量并计算侵蚀率。由河道偏移量计算出的长期平均走滑率沿断层为0.4±0.1～1.7±0.1mm/a，西南段低于中段。这种差异可能归因于映秀-北川断裂带东北延伸的滑动分区。此外，对河流纵剖面和沿断层地形变化的分析表明，QCF 的小推力分量向东北减小，在其东北端存在较小的法向分量。QCF走滑和垂滑运动的分布表明，LMSFZ中部断层滑动穿过岷山隆起向东北方向传播，并继续沿QCF滑动。此外，LMSFZ中南段的逆冲作用和QCF的右旋走滑断裂可能都适应了与青藏高原东扩相关的复杂变形。这些发现对限制潜在的地震灾害和了解区域构造变形的特征具有重要意义。LMSFZ 中南部的逆冲和 QCF 的右旋走滑断裂可能都适应了与青藏高原东扩有关的复杂变形。这些发现对限制潜在的地震灾害和了解区域构造变形的特征具有重要意义。LMSFZ 中南部的逆冲和 QCF 的右旋走滑断裂可能都适应了与青藏高原东扩有关的复杂变形。这些发现对限制潜在的地震灾害和了解区域构造变形的特征具有重要意义。