The Indian Ocean is divided into the Wharton Basin and the Mid-Indian Basin by the Ninety East Ridge of about 5,000 km in length. The two basins are connected by an abyssal gap in the middle of the Ridge. Such connectivity plays a key role in deep water exchange and has an important impact on the Indian Ocean circulation. The mooring system carries several kinds of ocean observation equipment, and the long-term marine environment parameters obtained provide data support for studying the characteristics and laws of deep circulation in the Indian Ocean.

The 52rd cruise of Ocean No. 1 by China is the key cruise to the implementation of the "Jiaolong" deep-sea exploration program. The sea area of the Ninety East Ridge of the Indian Ocean for operation this time is one of the key environmental areas planned in this program. Continuous observation on the fixed submersible buoys will contribute to the understanding of the characteristics and change rule of ocean dynamic environment in this sea area.