Stalactite
Topic: Landforms and their Evolution: Rivers, Groundwater, Glaciers, Waves and Wind · NCERT: Class 9, Ch 2 "Shaping of the Earth's Surface"; Class 11, Ch 6 "Landforms and their Evolution"
Meaning
A stalactite is an icicle-shaped deposit of calcium carbonate that hangs from the roof of a limestone cave. Water seeps through the rock and carries dissolved calcium carbonate with it. When a drop hangs from the cave roof, it loses carbon dioxide or evaporates, and it leaves a thin ring of calcium carbonate behind. Drop by drop, the ring grows down into a hanging spike. A stalactite is broad at the base, where it joins the roof, and it tapers to a point at the free end. Stalactites form slowly, and they show that water still moves and deposits minerals underground.
Example
The Borra Caves in Visakhapatnam district, Andhra Pradesh, are limestone caves with large stalactites hanging from their roofs.
Don't confuse with
- Stalagmite: it rises up from the cave floor. A stalactite hangs down from the roof. Memory aid: a stalactite holds "tight" to the ceiling.
- Cave pillar: forms when a stalactite and a stalagmite grow until they meet and join.