This story, though, raises the question of why there is but a single ejecta layer of iridium and shocked quartz in late Cretaceous rocks around the world.是什么意思_This story, though, raises the question of why there is but a single ejecta layer of iridium and shocked quartz in late Cretaceous rocks around the world.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句