Aeromagnetic survey △T maps clearly show that there are two SN-trending aeromagnetic anomaly zones along the Yarlung-Zangbo suture zone, and geological researches have confirmed that the ophiolite rock masses along the Yarlung-Zangbo suture zone extend nearly 2000 km in banded distribution and in ES direction;however, it has been known that the main chromium-containing ophiolite rock masses are distributed on the south bank of the Yarlung Zangbo River. There are discontinuously distributed chromium-containing ophiolite rock masses observed on the ground of Luobusha and Zedang, which have small sizes and whose geological study degree is relatively high. There is Xigaze rock mass outcropped westward on the ground, and there are huge rock masses, including Dangqiong, Purang, and Dongpo, further to the west. Aeromagnetic survey maps show that the rock masses, including Xigaze, Dongpo, Purang, and Dangqiong, are obviously consistent with aeromagnetic anomalies. Ground magnetic survey for the above rock masses accurately has determined the relationship between the known rock masses and the aeromagnetic anomalies, and the Luobusha and Zetang rock masses in the eastern section of the Yarlung Zangbo River belong to small rock masses within the negative anomaly range on the northern margin of the strong aeromagnetic anomaly in the south. The chromium-containing ophiolite rock masses along the river in the west are distributed discontinuously, exhibiting short banded or large three-dimensional masses;ground magnetic survey anomalies prominently reflect the unevenness of distribution of the ground magnetite rock masses, with strong serpentinization and strong magnetic anomaly on the margin of the rock masses (including surrounding rocks near rock masses), thus to accurately delimit the range of the rock masses. The aeromagnetic anomalies reflect that there are relatively enriched magnetic minerals in the rock masses; the magnetic minerals might come from the minerals containing such components as FeO, and Fe2O3 in the deep part, which upwelled to the upper crust with magma and formed Fe3O4 due to serpentinization, thus generating strong magnetism when the temperature was lower than 480 ºC. Inversion calculation shows that the magnetic bodies are within the depth range of 3–5 km;although the magnetite existing in the ophiolite rock masses and their surrounding rocks was not directly from mantle materials, the magma materials in the chromium-containing ophiolite rock masses were main material contributors to the magnetite. The distribution range of the magnetite roughly corresponds to the ore-containing ophiolite rock masses, thus the aeromagnetic and ground magnetic survey anomalies, together with such methods as magnetotelluric method and reflection seismic method, can yield the geophysical characteristics of the deep structure of the rock masses, in favor of delimiting prospective areas for ore prospecting.%航空磁测△T图上清楚显示出沿雅鲁藏布江缝合带具有南北两条航磁异常，地质研究确认沿雅鲁藏布江缝合带的蛇绿岩体呈带状东西向延续近2000 km，但已知主要含铬蛇绿岩体分布于雅鲁藏布江南岸。在罗布莎和泽当地表观测到断续分布着含铬蛇绿岩体，地质研究程度较高，岩体规模不大。向西地表有出露日喀则岩体，再西段有当穷、普兰、东坡等规模巨大的岩体。航空磁测图上显示出日喀则、东坡、普兰、当穷等岩体与清晰的航磁异常对应。对上述岩体进行的地面磁测准确地确定了已知岩体与航磁异常的关系，位于雅鲁藏布江东段的罗布莎与泽当岩体属于其南部强航磁异常北缘的负异常范围内的小岩体。西部沿江含铬蛇绿岩体是断续分布的，呈短条带状或较大的三度体；地面磁测异常突出反映出地表岩体磁铁矿分布的不均匀性，在岩体边缘（包括近岩体围岩）的蛇纹石化较强，磁异常亦较强，并由此较准确地圈定出岩体范围。航磁异常反映出岩体内部有相对富积的磁性矿物和磁性体，它们可能来自深部含FeO、Fe2O3等矿物在岩浆上涌到上地壳由于蛇纹石化而生成了Fe3O4，当温度低于480℃时形成较强的磁性。反演计算了磁性体位于3~5 km深度上，虽然蛇绿岩体及其围岩中存在的磁铁矿非直接来源于地幔物质，但含铬蛇绿岩体的岩浆物质是生成磁铁矿的主要物质贡献者。由此将航磁和地面磁测异常与大地电磁法、反射地震等方法结合可以给出岩体深部结构的地球物理特征，这有利于圈定找矿的远景地段。
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