Where would you look for a spectacular cave like this one?
Groundwater dissolves minerals and rocks into ions. Groundwater deposits those ions into different types of structures. Limestone caves are the best place to see this. Water erodes the cave and it has deposits structures like stalactites and stalagmites. The cave pictured here is Carlsbad Caverns in New Mexico.
Caves are known for their spectacular mineral structures. Caves are likely to be found in limestone where the groundwater level has gone down. This exposes the cave and its features. Stalactites are beautiful icicle-like formations. They form as water containing calcium carbonate drips from the ceiling of a cave. The word stalactite has a c, and it forms from the ceiling. Stalagmites form as calcium carbonate drips from the ceiling to the floor of a cave. The stalagmite grow upwards. The "g" in stalagmite means it forms on the ground. You can see examples of both stalactites and stalagmites in the Figure below.
Stalactites hang from the ceiling and stalagmites rise from the floor of a cave. The two together form a column.
If a stalactite and stalagmite join together, they form a column. One of the wonders of visiting a cave is to witness the beauty of these amazing and strangely captivating structures.
Some of the largest, and most beautiful, natural crystals can be found in the Naica mine, in Mexico. These gypsum crystals were formed over thousands of years. Groundwater that is rich in calcium and sulfur flowed through an underground cave. Check it out:
Naica Mine-Gypsum-Selenite at http://www.youtube.com/watch?v=6drrYFj91Ko (2:40)
column: A solid cave feature formed when a stalactite and a stalagmite grow together.
stalactite: Icicle-like formation of calcium carbonate. Forms from water dripping from the ceiling of a cave.
stalagmite: Deposit of calcium carbonate that grows upward in caves as water drips onto the floor.
- Groundwater dissolves minerals and carries the ions in solution.
- Groundwater deposits the material in caves as stalactites, stalagmites, and columns.
- Giant crystals may be found in caves.
Use this resource to answer the questions that follow.
Earth: The Skinny on Cave Formations at http://news.discovery.com/videos/earth-the-skinny-on-cave-formations.html (2:03)
- How does a cave form?
- What can cause caves to form?
- What is a stalactite?
- What is a stalagmite?
- How does a column form?
- Why is it important to watch your step in caves?
- Describe how groundwater creates depositional features.
- What are stalactites, stalagmites and columns?
- What conditions are best for cave formation?