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本文通过研究三江地区金沙江和澜沧江缝合带ＭＯＲＢｓ的时空分布配置、岩石组合类型、岩石地球化学及区域地化异常，揭示了地幔热柱对古特提斯岩石圈内ＭＯＲＢｓ源岩及ＭＯＲＢｓ的化学成分影响，讨论了地幔热柱对古特提斯洋开启的驱动机制及对岩石圈演化的制约作用。ＭＯＲＢ沿金沙江和澜沧江洋脊与ＯＩＢ分段产出，但在过渡地段，ＭＯＲＢ与ＯＩＢ交互产出，密切共生，并沿洋脊展示明显的地球化学异常。ＭＯＲＢ有３种类型，其中，富集型ＭＯＲＢ靠近ＯＩＢ分布区产出，相对富集ＬＲＥＥ、ＨＦＳＥ和ＬＩＬＥ，显示Ｅ－ＭＯＲＢ地化特征。亏损型ＭＯＲＢ远离ＯＩＢ分布区产出，相对亏损不相容元素，显示Ｎ－ＭＯＲＢ地化特征。过渡型ＭＯＲＢ在ＭＯＲＢ与ＯＩＢ过渡地段产出，则显示Ｔ－ＭＯＲＢ地化特征。ＭＯＲＢ地化特征和空间分布揭示，洋脊具有明显的块段特点，ＯＩＢ区洋脊具热幔柱洋脊特点，亏损型ＭＯＲＢ区洋脊具正常洋脊特征，而过渡型ＭＯＲＢ区段则具过渡型洋脊特征。混合模式计算表明，富集型和过渡性ＭＯＲＢｓ系亏损型ＭＯＲＢ端元与ＯＩＢ端元不同程度的混合产物，揭示地幔热柱物质与其周围的亏损地幔（Ｎ－ＭＯＲＢ源岩）发生了大规模物质能量交换。基于区域构造一岩浆事件分析，?
In this paper, the temporal and spatial distribution of MORBs in the Jinshajiang and Lancangjiang suture zones, the types of rock assemblages, lithogeochemistry and regional anomalies in the Sanjiang area were studied to reveal the influence of the mantle plume on the MORBs source rocks and MORBs in the Palaeo-Tethys lithosphere Composition, the driving mechanism of the mantle plume for the opening of the ancient Tethys Ocean and its restriction on the evolution of the lithosphere are discussed. The MORB yields along the Jinsha River and the Lancang Ridge with the OIB. However, in the transitional area, MORB and OIB are interbedded and closely intergrowth with obvious geochemical anomalies along the ridge. There are three types of MORBs. Among them, enriched MORBs are produced near the OIBs and relatively enriched in LREEs, HFSEs and Lils, indicating the geochemical characteristics of E-MORBs. Loss-type MORB is far away from the OIB distribution area, relative loss of incompatible elements, showing the N-MORB geochemical characteristics. Transitional MORB is produced at the transitional zone between MORB and OIB, indicating the geochemical characteristics of T-MORB. The MORB geomorphic features and spatial distribution reveal that the ridge has obvious block features, the OIB ridge has hot mantle ridge features, the ridge-shaped MORB ridge has normal ridge features, and the transitional MORB segment has Transitional ridge features. The mixed-mode calculations show that mixed MORB terminal and OIB terminal mixed products of depleted and transitional MORBs show that the mantle plumes and their surrounding depleted mantle (N-MORB source rocks) have large-scale material Energy exchange. Based on the regional tectono-magmatic event analysis,