Why are some lakes salty?
Show answer & explanation
Answer: No outlet causes accumulation
Underground salt deposits dissolve — Wrong. Dissolved minerals do contribute, but salt lakes form primarily because they have no outlet—water evaporates leaving minerals behind.
Seawater trapped long ago — Wrong. Most salt lakes weren't formed from trapped seawater. They become salty because water flows in carrying dissolved minerals, then evaporates, leaving salt behind with no outlet to the ocean.
No outlet causes accumulation ✓ — Correct! Salt lakes (Dead Sea, Great Salt Lake) are endorheic—no outlet river. Rivers flow in carrying dissolved minerals, water evaporates, but minerals stay. Over thousands of years, salts concentrate, becoming more saline than oceans! The Dead Sea is 34% salt (ocean is 3.5%). It's mineral accumulation through evaporation!