The presence and growth of CWCs on the slopes of the submarine seamounts in the south-western (SW) Dongsha area could be directly linked with the hard substrates provided by exhumed hydrocarbon-imprinted authigenic carbonates and fed by the food particles enhanced by high-velocity internal tides and near-bottom currents. The δ 13C (−7.36‰ to −1.15‰, V-PDB) and 87Sr/ 86Sr ratios (0.709126–0.709184) indicated that CWC aragonite skeletons had been precipitated from seawater without the involvement of seeping fluids.

The taxa identified were: Balanophyllia ( Balanophyllia) sp., Balanophyllia ( Eupsammia) sp., Lochmaeotrochus sp., Enallopsammia sp., Crispatotrochus sp.1 and Crispatotrochus sp.2. Cold-water corals (CWCs) were found to occur in association with authigenic carbonates in a cold seep area on the northern continental slopes of the South China Sea (SCS).