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对粤北南雄地区一个副片麻岩中56个碎屑锆石的年代学研究显示,华夏腹地晚新元古代沉积岩主要由新太古代(～2.5 Ga)和Grenville期(0.9～1.1 Ga)的碎屑物质组成,其中还包含了一定数量的中元古代和少量中太古代(3.0～3.2 Ga)和古太古代(3.76 Ga)的碎屑物质.这些发现表明华夏地块存在非常古老的物质.37颗锆石的Hf同位素组成显示这些碎屑物质具有不同的成因,少量结晶于有较多新生地壳组分熔融产生的岩浆,而大多数结晶于古老地壳组分部分熔融产生的岩浆.锆石U-Pb年龄和Hf同位素综合研究指出华夏地块新生地壳物质主要是在2.5～2.6 Ga形成,中太古代(3.0～3.3 Ga)、古元古代晚期(～1.8 Ga)和古太古代(～3.7 Ga)也是重要的地壳生长期.中元古代-新元古代的岩浆活动非常强烈,但主要表现为古老物质的再循环,只有很少有新生地壳增生.～2.1 Ga模式年龄峰值的存在和同时代锆石的缺失表明许多锆石的古元古代模式年龄很可能是源区中新太古代和古元古代晚期物质混合的结果.
The chronological study of 56 detrital zircons from an adjacent gneiss in the Nanxiong area of northern Guangdong shows that late Neoproterozoic sediments in the hinterland of the Huaxia are mainly composed of Neo-Archean (~ 2.5 Ga) and Grenville (0.9 ~ 1.1 Ga) , Which also contains a certain amount of Mesoproterozoic and a small amount of detrital materials of Mesozoic age (3.0 ~ 3.2 Ga) and Paleo-Archean (3.76 Ga) .These discoveries show that there is a very ancient The Hf isotopic composition of the 37 zircons shows that these clastic materials have different origins. A small amount of crystallization occurs in the magma produced by the melting of more nascent crustal components, whereas most of the crystals are partially melted from the ancient crustal components. The zircon U-Pb age and Hf isotopic study indicate that the crustal material of the new crust in the Cathaysia Block is mainly formed in 2.5 ~ 2.6 Ga, Meso-Archaean (3.0-3.3 Ga), Late Paleoproterozoic (~ 1.8 Ga) and Paleo-Archean (~ 3.7 Ga) is also an important crustal growth period.Mprogenic-Neoproterozoic magmatic activity was very strong, but mainly manifested as recycling of ancient materials, with very little new crustal proliferation. Existence and contemporaneous zircon The absence indicates that the ages of many Paleoproterozoic zircons in most zircons are likely to result from the mixing of Neoarchean and Late Paleoproterozoic materials in the source area.