These folded rocks are composed of medium to thick bedded limestone of Ordovician and of thin bedded shale and siltstone of Silurian.是什么意思_These folded rocks are composed of medium to thick bedded limestone of Ordovician and of thin bedded shale and siltstone of Silurian.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句