Calcareous shells will not accumulate on the ocean floor when the water depth exceeds about 4,500 meters (around 15,000 feet).

Question

Quizplus · Accepted Answer

This is true because at depths below 4,500 meters, the pressure is too high for calcareous shells to form and accumulate. The shells dissolve due to the high levels of carbonic acid in the deep ocean. As a result, the ocean floor at these depths is mostly composed of non-calcareous sediments such as clay, silt, and volcanic ash.

Calcareous Shells Will Not Accumulate on the Ocean Floor When