awkwardsituationist: unlike many cave networks that are formed by the erosion of water over limeston
awkwardsituationist:unlike many cave networks that are formed by the erosion of water over limestone, the cueva de los verdes (or “green caves”) in the canary islands were formed three to five thousand years ago when surface lava cooled and hardened quickly while streaming lava continued to flow underneath the petrified basaltic layer. the caves were formed over a fifty kilometre squared area of more than one hundred volcanoes, the last of which erupted almost two hundred years ago. the lava tunnels can stretch for several kilometers, with some parts dropping well below sea level and reaching temperatures of up to six hundred degrees. photos by edwin jones (more cave photos) -- source link
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