SHANGHAI, July 9 -- China's deep-sea heavy-duty mining vehicle has completed a sea trial at a depth exceeding 4,000 meters, marking a significant breakthrough in the country's deep-sea mineral resource development technology.

The trial was conducted by the "Pioneer II," an engineering prototype independently developed by Shanghai Jiao Tong University, the Shanghai municipal government said on Tuesday.

The "Pioneer II" completed five diving and seabed mining operations, including a record-breaking dive to 4,102.8 meters, marking the first time a Chinese deep-sea heavy-duty mining vehicle has conducted trial operations at depths exceeding 4,000 meters.

The mining vehicle has pioneered several technologies in the country, including high-mobility deep-sea navigation at complex seabed terrains and composite drilling and mining of multiple types of deep-sea minerals.