
Which geologic process best explains the formation of coral atolls that encircle central lagoons?
Medium
Create a free account to see more questions and build your own quiz.
Get StartedWhich geologic process best explains the formation of coral atolls that encircle central lagoons?
Options:
- Subsidence of a volcanic island with upward coral growth
- Sea-level drop exposing a fringing reef
- Tectonic uplift of a coral platform
- Erosion of a coastal limestone plateau
Correct answer: Subsidence of a volcanic island with upward coral growth
Explanation: Darwin's subsidence theory (proposed in 1842) explains atolls: a volcanic island slowly sinks while reef-building corals grow upward, leaving a ring-shaped reef around a lagoon.
Created . Updated .