【摘要】 可能发生在中国扬子地台震旦—寒武系界线上地外撞击事件的目标地层应该是湘西北天门山震旦—寒武系界线上的Ni-Mo多金属元素富集层及其相对应的层位。文中分析了这一目标地层的展布和地质特征。这一特殊层位对于上下地层沉积环境的演变有着重要的意义。更多还原

【Abstract】 The objective stratum related to possible extraterrestrial impacted events in Yangtze paleo-platform of China is preliminarily confirmed by the Ni-Mo polymetal elements layer on the boundary of Sinian /Cambrian in Tianmenshan of western H unan Province.In the context,the di stribution and geological char-acteristics of the objective stratu m have been discussed.The special la yer is significant to the evolution o f depositional environment of stratigraphic formations up near and down n ear the objective stratum.更多还原