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对华夏地块南部粤中增城和赣南鹤仔3个基底变质岩的地球化学和碎屑锆石年代学研究表明,它们的原岩都是形成于晚新元古代的沉积岩.3个变质沉积岩都主要由新元古代早期(1.0～0.9Ga)的碎屑物质组成,并混有少量中元古代和新元古代中晚期(0.8～0.6Ga)的碎屑物,说明沉积物主要来源于一个遭受过Gondwana大陆聚合事件影响的Grenville期造山带.碎屑锆石的Hf同位素成分显示这些Grenville期锆石可能是造山旋回早期形成的弧与古老大陆碰撞产生的岩浆结晶的.结合华夏地块其他地区～1.0Ga年龄锆石的分布及形态学特征,本文认为华夏地块的南缘很可能曾经存在或者极其靠近一个Grenville期的造山带.而这期造山作用的时代与东印度以及东南极的Grenville造山带一致,且同样受到Gondwana大陆聚合事件的影响.因此,从Rodinia超大陆裂解到Gondwana超大陆聚合期间,华南地块很可能位于澳大利亚西部而与东印度和东南极相邻.
Geochemical and detrital zircon geochronology of three basement metamorphic rocks in southern Guangdong and Zengcheng in southern China and Crane in southern Jiangxi Province shows that all of their protoliths were sedimentary rocks formed in Late Neoproterozoic. Three metamorphic sedimentary rocks Are mainly composed of clastic matter in the early Neoproterozoic (1.0 ~ 0.9Ga) with a small amount of clastic materials in the middle and late Proterozoic and Neoproterozoic (0.8 ~ 0.6Ga), indicating that the sediments mainly come from one The Hf isotopic composition of the detrital zircons, which was affected by the Gondwana conglomeration event, shows that these Grenville zircons may be crystallized by the collision of the earlier formed orogenic arcs with the ancient continent. In this paper, the southern margin of the Cathaysian Block is likely to have existed or was extremely close to a Grenville orogenic belt, and the period of this orogeny is similar to that of East India and Southeast Antarctica The Grenville orogenic belt is consistent and subject to the same events as the Gondwana conglomeration, so it is likely that the South China block will be located between the Rodinia supercontinent and the Gondwana supercontinent Leah pole adjacent to the west and East India and southeast.