The Qilian Orogenic belt is one of the typical orogenic belts globally and a natural laboratory for studying plate tectonics. Many researchers have studied the ophiolite and high pressure and ultra-high pressure metamorphic rocks in the Qilian orogen and obtained valuable achievements. However, a hot debate exists on the basement property, the distribution of ophiolite, and the boundaries of tectonic units. Large-scale high-precision aeromagnetic surveys have recently been conducted in the Qilian Orogenic belt and adjacent areas. In this study, we are trying to analysis the tectonic framework of the Qilian Orogen using 1:500, 000 aeromagnetic data. The results provide geophysical perspectives for studying the structural framework and deformation of this area. According to the aeromagnetic ΔT anomaly map, the central and Southern Qilian have the same magnetic anomaly feature that noticeably differs from the North Qilian Orogenic belt and the Qaidam Block. This result indicates that the central and Southern Qilian have a unified magnetic basement and differ from the North Qilian orogenic belt and Qaidam Block. The map shows the distribution of ophiolite in the North Qilian orogenic belt. Linear magnetic anomalies represent the ophiolites because the mafic–ultramafic rocks usually have high magnetic susceptibility. The ophiolite belts are continuously distributed in the western part of North Qilian orogenic belt and have a large scale. However, the scale of the ophiolite belt and the outcropping of mafic–ultramafic rocks reduces when they pass through Qilian County to the east. The results indicate differences in the evolution process between the eastern and western parts of North Qilian, with Qilian County as the transition zone. This study also systematically defines the geophysical boundaries of the Qaidam Block, Qilian Block, North Qilian Orogenic belt, and Alxa block. It is proposed that the sinistral displacement of the Altun Fault is adjusted and absorbed by the series of NE-trending faults in the Qilian orogen and merge into the Longshoushan–Gushi Fault. The extension of the North Qilian Orogenic belt is strengthened by the neotectonics movement along the shearing direction, which separated the North Qilian Orogenic belt into several segments and formed a series of northeast-trending faults.

祁连造山带是全球典型的造山带之一，也是研究板块构造的天然实验室。许多研究者对祁连造山带蛇绿岩及高压、超高压变质岩进行了研究，并取得了宝贵的成果。然而，关于基底性质、蛇绿岩的分布以及构造单元的边界等问题存在着激烈的争论。近期，在祁连造山带及邻近地区开展了大规模高精度航磁调查。在本研究中，我们试图利用1：500、000航磁数据来分析祁连造山带的构造格架。研究成果为研究该区构造格架和变形提供了地球物理视角。根据航磁ΔT异常图，中、南祁连地区具有相同的磁异常特征，但与北祁连造山带和柴达木地块存在明显差异。这一结果表明，中、南祁连地区具有统一的磁基底，与北祁连造山带和柴达木地块存在差异。该图显示了北祁连造山带蛇绿岩的分布情况。线性磁异常代表蛇绿岩，因为镁铁质-超镁铁质岩石通常具有高磁化率。蛇绿岩带在北祁连造山带西段连续分布，规模较大。但蛇绿岩带向东经过祁连县后，其规模和出露的镁铁质—超镁铁质岩逐渐减少。结果表明，以祁连县为过渡带，北祁连东西部演化过程存在差异。本研究还系统界定了柴达木地块、祁连地块、北祁连造山带和阿拉善地块的地球物理边界。认为阿尔金断裂的左行位移被祁连造山带一系列北东向断裂调整吸收，并入龙首山—固始断裂。沿剪切方向的新构造运动加强了北祁连造山带的伸展，将北祁连造山带分成了数段，并形成了一系列北东向断裂。