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共和盆地周缘晚古生代镁铁质火山岩分布于南侧阿尼玛卿蛇绿岩带,北侧宗务隆构造带和两者间的苦海-赛什塘带.阿尼玛卿带的镁铁质火山岩构成了以玛积雪山OIB为中心向东西两侧过渡为MORB的古洋脊热点构造,苦海-赛什塘带的镁铁质火山岩由E-MORB和大陆裂谷玄武岩构成,而宗务隆构造带的岩石则为略显富集的N-MORB.普遍低的Nb/U和Ce/Pb比值反映了区域性的镁铁质岩浆源区OIB物质的的影响.从岩石的地球化学特征,空间分布和构造关系分析,阿尼玛卿带与苦海-赛什塘带构成一古三联点构造.而苦海-赛什塘坳拉谷的形成为宗务隆带镁铁质火山岩源区遭受玛积雪山OIB物质可能的交代混染提供了构造通道.古三联点构造的出现和宗务隆带的开裂分割了本区诸造山带和地块.热点构造是本区晚古生代拉张体制主要的深部动力学原因,而它引发的三联点构造是形成多块体洋陆格局的主要构造形式之一.
The Late Paleozoic mafic volcanic rocks in the periphery of the Gonghe Basin are distributed in the Animianqing ophiolite belt in the south, the Zongwulong tectonic belt in the north and the bitter Sea-Seishun zone in both. Volcanic rocks constitute the hotspot of the ancient ocean ridge that transitions to the MORB centering on the Oma mountains and the OIB center. The mafic volcanic rocks of the Ostuary-Seishitang belt consist of E-MORB and continental rift basalts, The Long structural belt rocks are slightly enriched N-MORB. The generally low ratios of Nb / U and Ce / Pb reflect the OIB material effects in the regional mafic magma source zone. From the geochemical characteristics of the rocks , The spatial distribution and tectonic relation analysis, the Animaden belt and the oceans-Saishitang belt form an ancient triple point structure, while the formation of the Tashi-Seishutang Aura valley is the source region of the mauxenian mafic volcanic source The possible channeling and mixing of the OIB material in the Masai Snow Mountain provides a structural channel.The emergence of the Paleozoic point structure and the cracking of the Zonglun Long zone divide the orogenic belts and the parcels in this area.The hotspot structure is characterized by the Late Paleozoic stretching system The main reason for the deep dynamics, which triggered the triple point structure is the formation of multi-block ocean land One of the main structural form Agency.