Stalactites hang from the ceiling. Stalagmites rise from the floor. Some even meet to create a column. Other formations look like needles, popcorn, pearls and flowers.
A visitor still remembers the memory aid she learned long ago from her fifth-grade teacher. Stalactites have to hang on "tight" to the ceiling or they might fall off. And be careful about stalagmites -- you "might" trip over one on the floor.
One of the first questions that visitors have is how did Carlsbad Cavern form? Guides explain that it did not result from the action of water and streams like other limestone caves. Instead, it was created by the action of sulfuric acid.
The limestone developed about 250 million years ago. Then, within the last 20 million years, movements in the earth pushed the rock upward, forming the Guadalupe Mountains. Today these mountains extend from west Texas into southeast New Mexico.
The action of oil and natural gas created hydrogen sulfide in the limestone. The hydrogen sulfide reacted with oxygen in rainwater moving through the rock. Sulfuric acid developed. The acid created the caves by dissolving the limestone in its path.
Later, the water and most of the acid left the caves as the Guadalupe Mountains continued to rise. This permitted freshwater to move through. The freshwater left behind minerals. These minerals became the formations and shapes on the ceilings, walls and floors of the caves.
最新
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25