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锡林郭勒杂岩是中亚造山带内出露面积较大的强变形变质地质体,其形成时代与性质存在较大认识上的分歧.对锡林浩特东南锡林郭勒杂岩定名处黑云斜长片麻岩进行了岩相分析和SHRIMP锆石U-Pb年代学研究,其形成年龄下限由杂岩中碎屑岩浆锆石SHRIMP U-Pb年龄限定为437±3 Ma,其形成上限由侵入于杂岩内的石榴石花岗岩SHRIMP锆石U-Pb年龄限定为316±3 Ma.这表明该杂岩的沉积成岩年龄晚于晚奥陶纪～早志留纪,因此不是前寒武纪古老地质体.结合实际野外观察和室内岩石特征分析,该杂岩可能是一套经历强变形与变质作用的古生代弧前浊积岩建造.杂岩中碎屑锆石还给出分散的前寒武纪年龄,最老可达3.1 Ga,这些锆石既可能来源于华北基底,也可能来源于南蒙微大陆,抑或暗示该区存在600～800Ma或更古老(3.1 Ga)块体,表明其碎屑来源的复杂性.
The Xilin Gol complex is a strongly deformed metamorphic geological body with a large exposed area in the Central Asian orogenic belt, and there is a big difference in understanding of the age and nature of the Xilin Gol complex. For the lithofacies analysis and SHRIMP zircon U-Pb zircon dating, the lower age of formation is defined by SHRIMP U-Pb age of clastic magmatic rocks in the complex as 437 ± 3 Ma, and the upper limit of its formation is determined by the intrusive pomegranate The SHRIMP zircon U-Pb age for stone granites was limited to 316 ± 3 Ma, indicating that the sedimentary diagenesis of this complex was later than that from Late Ordovician to Early Silurian and was therefore not an ancient Precambrian geological body. And the analysis of indoor rock characteristics, the complex may be a set of Paleozoic archaeal pre-turbidite that experienced strong deformation and metamorphism.The detrital zircons in the complex also give the Precambrian age dispersed, the oldest 3.1 Ga. These zircons may originate from the North China basement or from the South Meng micro-continent, or may suggest the presence of 600 ~ 800Ma or older (3.1 Ga) blocks in this area, indicating the complexity of the source of these debris.