The first member was formed in the beginning of downfaulting period during which alluvial fan, fluvial and delta facies were mainly developed.是什么意思_The first member was formed in the beginning of downfaulting period during which alluvial fan, fluvial and delta facies were mainly developed.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句