How are caves formed?
Show answer & explanation
Answer: Water dissolves rock over time
Animals dig them out — Wrong. While some animals live in caves or enlarge small holes, they don't create large cave systems. Most caves form through chemical dissolution of rock by water, a process taking thousands to millions of years.
Water dissolves rock over time ✓ — Correct! Most caves form in limestone rock through a process called dissolution. Rainwater absorbs carbon dioxide from air and soil, becoming slightly acidic. This weak carbonic acid slowly dissolves limestone as it seeps through cracks. Over thousands of years, this creates underground caverns. Stalactites and stalagmites form from minerals redeposited by dripping water!
Wind erosion hollows rocks — Wrong. Wind erosion can create shallow rock shelters in deserts, but not deep underground cave systems. Most caves form through water dissolving soluble rocks like limestone underground. Wind erosion is a surface process and too weak to create large underground chambers.
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