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广西东南部十万大山旧州岩体中副变质麻粒岩包体中锆石U-Pb定年和Hf同位素分析结果显示,麻粒岩原岩物质主要来源于新元古代-中元古代(564～1061Ma)的碎屑物质,峰值年龄为～822 Ma,其物源主要来自与新元古代Rodinia超大陆裂解有关的火成岩.部分锆石为古元古代(1778～2227 Ma),并有少量中太古代-古太古代物质(最老锆石年龄为(3551±8)Ma),暗示十万大山或周缘地区可能存在非常古老的地壳物质.另外,还获得一组早中生代岩浆锆石((234±2)Ma)和一组晚古生代变质锆石((253±3)Ma)年龄.锆石Hf同位素分析结果指示麻粒岩包体的原岩沉积物具有多来源特征,既有古老再循环地壳物质的参与,也有新生物质的贡献.锆石U-Pb-Hf同位素特征指示十万大山地区在～253 Ma经历了一次强烈的热事件,原岩发生麻粒岩相变质作用,而后在抬升过程中(～234 Ma)发生部分熔融形成花岗岩,麻粒岩包体为熔融残留体。
The zircon U-Pb dating and Hf isotopic analysis of the paragenetic granulite inclusions in the old state rocks of the Shiwandashan Mountains, southeastern Guangxi, show that the original rock materials of the granulite come mainly from Neoproterozoic to Mesoproterozoic (564 ~ 1061Ma), with a peak age of ~ 822 Ma, and its source mainly comes from the igneous rocks associated with the Neoproterozoic Rodinia supercontinent. Some zircons were Paleoproterozoic (1778 ~ 2227 Ma) with a small amount of medium The ancient-ancient Archean material (the age of the oldest zircon is (3551 ± 8) Ma) suggests that there may be very ancient crustal material in the Shiwandashan Mountains or the surrounding area. In addition, a series of Early Mesozoic magmatic zircons ( ± 2 Ma) and a group of late Paleozoic metamorphic zircons (253 ± 3 Ma) ages.The results of Hf isotopic analyzes of zircons indicate that the protolith deposits of granulite inclusions have multi-source characteristics, both ancient recirculation The involvement of crustal material and the contribution of new biomass.The U-Pb-Hf isotopic characteristics of zircon indicate that the Shiyawandashan area experienced a strong thermal event at ~ 253 Ma, the granulite facies metamorphism of the original rock, During the process (~234 Ma), partial melting took place to form granites with granulite inclusions Residual melt body.