The Tibetan Plateau, which is located in the transitional zone of the Gondwana and Laurasia, plays a key role in studying the supercontinental convergence and cracking of Gondwana. As a result of the opening of the Tethys Oceans, the northern Gondwa⁃na started to rift during Late Paleozoic. Continental intraplate basaltic magmatism is typically considered to have been linked with con⁃tinental break-up. Permian continental intraplate basaltic rocks have been recognized in the Tibetan Plateau and are considered as re⁃cording the Late Paleozoic rift of the northern Gondwana. However, these rocks mainly occur in the Qiangtang and Panjal Traps of western Tibetan Plateau, but no coeval basaltic rocks have been reported in eastern Tibetan Plateau. In this paper the authors present the results of the study of the Early Permian gabbros in the Leiwuqi area of eastern Tibetan Plateau. LA-ICP-MS zircon U–Pb dat⁃ing reveals that the gabbros formed at 280±2Ma. The geochemical features of these gabbros are comparable with those of continental intraplate basalts (WPB). They exhibit positive values of zirconεHf(t) (5.1~11.5), suggesting a depleted mantle origin. Taking into ac⁃count previous data, the authors hold that these gabbros were related to the Early Permian Qiangtang-Panjal mantle plume. There⁃fore, Early Permian continental intraplate basaltic rocks developed in both western and eastern Tibetan Plateau and they were linked with the continental break-up of northern Gondwana and the opening of the Bangong Co-Nujiang Tethys ocean.%青藏高原处于冈瓦纳大陆与劳亚大陆的交汇部位，是研究冈瓦纳大陆裂解与聚合过程的关键地区。晚古生代伴随着特提斯洋的打开与扩张，冈瓦纳大陆北缘发生了广泛的裂解作用。大陆板内岩浆作用是超大陆裂解的重要证据。在青藏高原内部已有二叠纪大陆板内特征基性岩的报道，它们是该裂解事件的记录。然而，根据目前的相关报道，这些岩石主要出露在青藏高原的西部，以羌塘和潘伽地区为主，在其他地区尚无相关报道。首次报道的藏东类乌齐地区早二叠世辉长岩LA-ICP-MS锆石U-Pb定年结果显示，辉长岩的形成年龄为280±2Ma。全岩地球化学资料表明，辉长岩具有与典型大陆板内玄武岩类似的地球特征。辉长岩具有明显正的锆石εHf(t)值（5.1~11.5），暗示其岩浆起源于亏损的地幔源区。结合区域地质资料，认为类乌齐辉长岩是冈瓦纳大陆北缘早二叠世裂解的产物。因此，早二叠世大陆板内基性岩浆作用在青藏高原东部也有出露，它们是在羌塘-潘伽地幔柱活动的作用下，冈瓦纳大陆北缘裂解与班公湖-怒江洋打开和扩张的结果。
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