China has expanded its international seabed mining area to 86,000 square kilometers in the last five years, the Ministry of Land and Resources said on its website on Tuesday.

With the expanded area, China has become the country with the most categories of seabed mineral in the world. 

This was achieved as a result of world-class deep-sea exploration equipment such as the manned deep-sea submersible, Jiaolong, and a well-established scientific expedition system, the ministry said.

A staff member from the Changsha Research Institute of Mining and Metallurgy Co in Central China's Hunan Province told the Global Times that it maps out mineral resources under a patch of the East Pacific that covers about 72,000 square kilometers.

The institute is a subsidiary of China Minmetals Corp, which is one of only 27 contractors for deep-sea mining within the Pacific Ocean under the International Seabed Authority.

Seabed mineral resources mainly refer to three types of deposits - polymetallic nodules, cobalt-rich crusts and polymetallic sulfide deposits. Some of these metals are vital ingredients for emerging industries such as new-energy vehicles.

There are huge quantities of deep seabed minerals and they are highly concentrated compared with their land equivalents, the anonymous staff member told the Global Times earlier in an interview.