CCD (Carbonate Compensation Depth)

The Carbonate Compensation Depth (CCD) is the ocean depth at which the rate of carbonate sediment dissolves faster than it accumulates. Below this depth, calcium carbonate from shells and coral, which usually settle on the seafloor, gradually breaks down due to increasing pressure and acidity of seawater. As a result, deeper ocean floors often lack these carbonate materials, impacting marine ecosystems and sediment composition. The CCD is a crucial factor in understanding ocean chemistry, sedimentation processes, and the history of Earth's climate, as it reflects the balance between biological production and chemical dissolution of carbonates.