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报道了贵州北部板溪群鹅家坳组晶屑凝灰岩SHRIMP锆石U-Pb年龄,结果显示扬子克拉通内板溪群沉积中期广泛的酸性火山事件的年龄是～780Ma.研究表明它们与扬子克拉通周边同期基性岩墙群和火山岩也构成了克拉通范围的双峰式岩浆活动系列,该期克拉通范围的双峰式火山岩浆组合仅是新元古代中期(835～720Ma)强烈的幕式火成岩系列的一部分.由此可见,扬子克拉通新元古代中期广泛的双峰式、幕式岩浆火山事件系列与弧陆碰撞造山构造模式是矛盾的,它们是裂解构造过程的记录,可能与导致Rodinia超大陆裂解的幕式地幔柱活动有关.
The SHRIMP zircon U-Pb dating of the crystalline tuff in the Gojiajia Au Formation in Banxi Group, northern Guizhou, is reported. The results show that the age of extensive acidic volcanic events in the mid-Banchi group of the Yangtze craton is ~ 780 Ma, Through the same period, the basic dyke swarms and volcanic rocks also formed a series of bimodal magmatic activities in the cratonic range. The bimodal volcanic assemblage in the craton range is only a strong curtain in the mid-Neoproterozoic (835-720 Ma) Type igneous series .Therefore, the wide range of bimodal and episodic magmatic volcanic events in the mid Neoproterozoic of the Yangtze craton are in contradiction with the continent-continent collision orogeny. They are records of the tectonic process of cracking and may be related to The curtain mantle plume activity that led to the break-up of the Rodinia supercontinent.