China's Explorer 2 scientific research ship and Deep-sea Warrior manned submersible returned to Sanya City on September 25 after completing the in-situ observation of deep-sea geology and the sea trial of domestic equipment in the South China Sea. With the 4,500-meter-class manned submersible, the deep-sea voyage completed the in-situ observation of the topography of the deep-water well site and obtained survey data of the underwater production system. The deep-sea well serves as an important source of clean energy for the Hainan Free Trade Port and the Guangdong-Hong Kong-Macao Greater Bay Area.