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松多群是冈底斯B型山链变质基底的组成部分之一 ,并于晚三叠世—晚第三纪雅江缝合带俯冲超碰撞阶段演化为该B型山链活化根带逆冲推覆超岩片 ,系冈瓦纳大陆北缘于震旦—寒武纪小洋盆及陆缘火山沉积的产物。松多群岔萨岗组、马布库组、雷龙库组及罗马岭超镁铁质岩带 ,彼此间均为构造接触 ,实为一套构造岩石组合体 ,由时代相近而来源、性质不同的地质体构成 ,并经历了低绿片岩相—低角闪岩相变质作用和 4期主要构造变形。岔萨岗组主体为变质基性火山岩 ,化学成分相当TMORB ;马布库组、雷龙库组片岩、石英岩相当于被动陆缘泥砂质复理石建造及石英质复理石建造。罗马岭超镁铁质岩经综合分析判别则形成于伸展裂陷小洋盆构造环境。因而得出松多群为一较完整有限小洋盆火山沉积产物的结论。
Songdoqun is one of the components of the metamorphic basement of the B-type mountain chain in the Gangdise area and evolved into the B-type mountain chain activation root zone thrusting in the Late Triassic-Late Tertiary Yajiang suture subduction and supercritical phase Overlying the rock fragments, the Department of the northern margin of the Gondwanaland in the Sinian - Cambrian small oceanic and continental volcanic deposits. The Songdu Group, the Sagu Group, the Mabu Group, the Leilongku Group, and the Roma Ridge ultramafic belt are all structurally in contact with each other and constitute a set of tectonic rock assemblages that are similar in source and age Different geological bodies, and experienced low-greenschist facies-amphibolite facies metamorphism and four major structural deformation. The main component of the Chasangang Formation is metamorphic base volcanic rock, and its chemical composition is quite similar to that of TMORB. The Mbukou Formation and the Leilongku Group schist and quartzite are equivalent to the construction of passive continental margin muddy flysch and quartz flysch. The Roma Ridge ultramafic rocks are formed in extensional rifting small oceanic basins by comprehensive analysis and discrimination. Therefore, it is concluded that the Songdo Group is a more complete and limited small-basin volcanic sedimentary product.