But with half the world's limestone still to be explored, 但世界上仍有一半石灰岩洞尚未被开发
they came across whole galleries filled with the most unusual formations, 他们发现了成片叹为观止的地貌
like these 5-metre cones, frosted with the most delicate crystals. 例如这些5米高的石锥 上面布满了雪霜一样的松脆结晶
The walls were covered with the most delicate and fragile crystals. 石壁上布满了光洁美丽的脆弱结晶
It mixes with oxygen and the water, 与水中的氧发生化合反应
is actually coloured white with sulphuric acid. 竟然被硫酸染成了白色
keeping their grip with microscopic hooks on their fins. 它们用鳍上的小钩紧紧抓住岩壁
It's the same story with other troglodytes. 其它穴居动物也是同样的情况
The rocky outcrops of New Zealand's Poor Knight Islands are riddled with sea caves 新西兰坡·骑士岛的 岩礁下布满了海蚀洞