Three different-age series of granitoid veins and dikes of the Baikal–Muya fold belt were studied. Two of them, plagiogranites of the ophiolite complex and the first postophiolitic plagiogranites, are associated with the suprasubduction ophiolites of the eastern Baikal–Muya belt. The third series is represented by hypabyssal tonalite–plagiogranite–leucogranite complex of the Kichera zone in the western Baikal–Muya belt. The composition and isotope-geochemical characteristics (ε_Nd(T) = –0.9; –1.3) of the plagiogranite veins no more than 60 cm thick, and ε_Nd(T) values (–1.8…+ 0.2) of host layered leucocratic gabbros in the Sredne-Mamakan ophiolitic complex are consistent with the previously established suprasubduction nature of the ophiolite association. Tonalites and plagiogranites of the dyke system of the post-ophiolitic magmatic series intersect the dunite–pyroxenite–gabbro banded series of the Sredne-Mamakan ophiolites of the eastern Baikal–Muya fold zone. High Sr/Y ratios and low concentrations of Y and heavy REE indicate that these granitoids are ascribed to the adakite series. LA-ICP-MS study of zircon from post-ophiolitic plagiogranites yields the crystallization age of 629 ± 5 Ma. Sm–Nd isotope-geochemical characteristics of plagiogranitoids (ε_Nd(T) = +2.5; +4.0) in combination with geochemical data confirm their origin during partial melting of a mafic protolith corresponding to the Neoproterozoic oceanic crust. The adakitic granitoids in the Kichera zone of the western Baikal–Muya belt belong to the tonalite–leucogranite differentiated series of the hypabyssal complex, which has no a direct spatial relationship with unambiguous ophiolite associations. The chemical composition and Sm–Nd isotope-geochemical characteristics of these rocks (ε_Nd(T) = +3.2…+7.1) indicate the heterogeneity of the predominantly juvenile island-arc or oceanic Neoproterozoic crust, which experienced partial melting at 595 ± 5 Ma.

研究了贝加尔湖-穆亚褶皱带的三个不同年龄系列的花岗岩脉和堤防。其中两个是蛇绿岩复合物的斜长花岗岩和第一个后蛇纹岩斜花岗岩，与贝加尔湖东部-穆亚带的超俯冲蛇绿岩有关。第三个系列是贝加尔湖-穆雅带西部奇切拉地区的海底斜长石–斜长花岗岩–斜长花岗岩复合体。该组合物和同位素地球化学特征（ε_钕（T）= -0.9; -1.3）的斜长静脉厚不超过60厘米，并且ε_钕Sredne-Mamakan蛇绿岩复合体中寄主层白垩纪辉长岩的（T）值（–1.8…+ 0.2）与先前确定的蛇绿岩超俯冲性质一致。后蛇纹岩浆岩系的脉系的同色岩和斜长花岗岩与贝加尔河-穆雅褶皱带东部的Sredne-Mamakan蛇绿岩的辉光岩-辉绿岩-辉长岩带状系列相交。高的Sr / Y比和低的Y浓度和重稀土元素表明这些花岗岩类归因于the石系列。LA-ICP-MS研究了后蛇纹岩斜长花岗岩中的锆石的结晶年龄为629±5 Ma。钐-钕plagiogranitoids的同位素地球化学特征（ε_钕（T）= +2.5；+4.0）与地球化学数据相结合，证实了它们的起源是在对应于新元古代大地壳的镁铁质原生质的部分熔融期间。贝加尔湖-穆雅地带西部奇切拉地区的adakitic花岗岩类属于斜纹岩-斜纹花岗岩区分的斜纹复合体，与明确的蛇纹岩组合没有直接的空间关系。的化学组成和Sm -这些岩石的钕同位素地球化学特征（ε_钕（T）= + 3.2 ... + 7.1）表示的主要是少年岛弧或海洋新元地壳的异质性，经历了局部熔融，在595±5嘛。