【摘要】 从湘西北天门山震旦—寒武系界线上发现的冲击砾裂、冲击角砾、冲击岩脉、微球粒撞击玻粒(microirghi-zites)、微球粒玻璃陨石(microtektites),特别是陨石碎屑残迹现象,可能表明:在震旦—寒武系界线上曾经发生过地外撞击的事件。更多还原

【Abstract】 Geologic marks related to extraterrestrial impact events, such as im pact split gravels, impact brecciate layers, impact dikes, microirghizites, micr otektites, especially meteoritic residues, were discovered on the boundary betwe en Sinian/Cambrian in Tianmenshan of Western Hunan, which may possibly demonstra te that an extraterrestrial impact event has ever occurred there on the SC bound ary.更多还原