在 Nanxiongarea 从帕拉片麻岩为 56 由岩屑形成的锆石标明日期的 U-Pb,北广东省,显示在 Cathaysiahinterland 的最近的 Neoproterozoic 沉积由众多的 Grenvillian 和 Neoarchaean 组成碎屑状的材料,以及 someMesoproterozoic 岩屑。次要的 Paleoarchaean (3.76 Ga ) 和 Mesoarchaean (3.0—3.2 Ga ) 锆石,是在华南的最旧的锆石,第一也在沉积被发现,建议卡赛西亚·布洛克可以包含很旧的材料。thirty-sevenzircons 的 Hf 同位素作文表明这些碎屑状的材料有不同起源。次要的锆石从产生从的岩浆结晶相对少年外壳,当大多数锆石的父母岩浆从古老的外壳被导出时。U-Pb 标明日期和这些锆石的 Hf 同位素分析的集成建议在 Cathaysia 块的少年外壳的产生主要发生在 2.5 点—2.6Ga。Mesoarchaean (3.0—3.3 Ga ) ,迟了的 Paleoproterozoic (~ 1 .8 Ga ) 和 Paleoarchaean (~ 3 .7 Ga ) 可以也是外壳的生长的重要事件。Grenvillian magmatism 是极其强烈的,但是它主要涉及与少年外壳的很少形成古老的外壳的部件再循环。~ 2 .1 Ga Hf 模型年龄的 Themarked 存在和有结晶化的锆石的缺席在~ 2 .1 Ga 变老建议许多锆石的父母岩浆可能从由 Neoarchaean 和迟了的 Paleoproterozoic 材料组成的混合来源被导出。
U-Pb dating for fifty-six detrltsl zircons from a paragneiss in Nanxiong area, northern Guangdong Province, Indicates that the latest Neoproterozoic sediments in Cathaysia hinterland are composed of numerous Grenvillian and Necerchaean clasUc materials, as well as some Mesoproterozolc detritus. Minor Paleoarchaean (3.76 Ga) and Mesoarchaean (3.0-3.2 Ga) zircons, which are the oldest zircons In South China, also are firstly found in the sediments, suggesting that the Cathaysia Block may contsln very old materials. The Hf isotope compositions of thirty-seven zircons reveal that these clastlc materials have different origins. Minor zircons crystslllzed from magma generated from relatively juvenile crust, while the parental magma of most zircons was derived from ancient crust. Integration of U-Pb dating and Hf Isotope analysis of these zircons suggests that the generation of juvenile crust in the Cathaysia block mainly occurred at 2.5-2.6 Ga. Mesoarchaean (3.0-3.3 Ga), late Paleoproterozolc (-1.8 Ga) and Paleoarchaean (-3.7 Ga) may also be important episodes of crustal growth. Grenvllllan magmatism is extremely Intense, but it mainly involved recycling of ancient crustal components with little formation of Juvenile crust. The marked presence of -2.1 Ga Hf model ages and the absence of the zircons with crystsllizatlon ages at -2.1 Ga suggest that the parental magma of many zircons was probably derived from the mixed source consisting of Neoarchaean and late Paleoproterozoic materlals.