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黄河源区位于青藏高原东北部,区内主要为三叠系沉积地层,发育一系列由北向南的推覆构造带,间有早期近直立的韧性剪切带。笔者对黄河源地区巴颜喀拉山群沉积岩进行了磁组构分析,结果显示岩石磁化率各向异性度P值和磁化率百分率各向异性度H值均不大,反映该地区总体韧性变形较弱,较强韧性变形仅发育于局部地段;岩石磁组构具有磁面理发育、磁线理不发育、磁化率椭球呈压扁形椭球体的特点,反映在挤压应力作用下,岩石发生了压扁变形,主应力方位主要为NNE-SSW(近SN)向,其次为NE-SW向。根据岩石磁组构分析认为黄河源地区存在两条韧性剪切带,韧性剪切带与现今湖泊水体的展布有一定的耦合关系;北部韧性剪切带沿现今黄河河谷分布,控制着扎陵湖、鄂陵湖和玛多“四姐妹湖”的展布;南部韧性剪切带沿岗纳格玛错—野牛沟一线展布,控制着岗纳格玛错和尕拉拉错等残余湖泊的分布。
The source region of the Yellow River is located in the northeastern part of the Qinghai-Tibet Plateau. The main source area of the Yellow River is the Triassic sedimentary strata. A series of nappe structures from north to south are developed with early and upright ductile shear zones between them. The authors analyzed the sedimentary rocks of Bayan Harness Group in the Yellow River source area and found that the anisotropy of rock magnetic susceptibility P and the percentage susceptibility H of magnetic susceptibility were not large, which reflected the overall ductile deformation The weaker and stronger ductile deformation is only developed in the local area. The rock magnetic structure has the development of magnetic texture, the magnetism lineage is not developed, the magnetic susceptibility ellipsoid has the characteristics of flattened ellipsoid, which is reflected by the compressive stress, Squeeze deformation occurred. The main stress orientation was mainly NNE-SSW (near SN), followed by NE-SW. According to the rock magnetic structure analysis, there are two ductile shear zones in the source region of the Yellow River, and the ductile shear zone has a certain coupling relationship with the present lacustrine water body distribution. The northern ductile shear zone distributes along the present Yellow River valley, Lake, Eling Lake and Maduo “Four Sisters Lake ” of the distribution; Southern ductile shear zone along the Gang Nagmar wrong - Ye Niugou line distribution, control of Gunagamar fault and Jalala fault, etc. Residual lake distribution.