Question

What is a human made structure that is sunk in a region that was previously inhabited by coral reefs?

Answer 1

The answer is artificial reef. Its a man made underwater structure typically built to promote marine life areas with a generally features bottom to control erosion, block ship passage or improve surfing. Artificial reef improve marine life in a certain area and deprive a new location for fishermen to fish and which works to ease the pressure on natural reefs.
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