中國的目標：日本南鳥島近海的錳結核！
~日本今年在其專屬經濟區成功鑽探稀土
~東京大學分析中國稀土論文並發表結果
我們將為您提供讀賣新聞上發表的文章摘要。
University of Tokyo and Yomiuri Shimbun:
On November 30th, University of Tokyo and Yomiuri jointly announced the “analysis results of China’s rare earth paper.”
Currently, China is accelerating rare earth surveys in the high seas off Japan’s Minamitorishima.
1. China’s target is the seabed around Minamitorishima in the high seas of the Northwest Pacific Ocean.
2. China is focusing on high seas seabed surveys off Japan’s Minamitorishima to obtain seabed rare earths.
University of Tokyo and Nippon Foundation:
In June 2024, Japan succeeded in “collecting manganese nodule deposits” within the EEZ off the coast of Minamitorishima.
1. Rare earth reserves are more than 75 years’ worth of Japan’s consumption.
2. Rare earths are distributed on the seabed within Japan’s exclusive economic zone (EEZ).
3. Rare earth resources are found in the deep sea off the coast of Minamitorishima, at a depth of several thousand meters.
Distribution of rare earths around Minamitorishima:
1. Mud with high concentrations of manganese and rare earths: Rare earth mud is abundant.
2. Cobalt-rich mineral nodules: Cobalt-rich crusts are widely distributed.
The University of Tokyo and Yomiuri analyzed the distribution, amount, and origin of rare earths around Minamitorishima in a research paper in an international journal.
A sharp increase in rare earth-related papers from China:
In 2017, China announced its first deep-sea resource development plan.
1. January 2020 to October 2024: 66 Chinese research papers published in international academic journals.
2. 2015 to 2019: The number of Chinese research papers increased significantly from 9.
3. There are particularly many papers on manganese nodules (26) and rare earth mud (25).
China’s rare earth research areas are concentrated in the south and east of Minamitorishima. Most of the research is conducted within the borders of Japan’s EEZ.
ISA: International Seabed Authority:
The United Nations Convention on the Law of the Sea, to which 170 countries (including Japan and China) belong.
1. The ISA grants each country “exploitation rights only within the EEZ.”
2. The ISA prohibits “mining and development of seabed resources in the high seas.”
Existence of exclusive exploration rights by China:
However, the ISA has granted a total of 31 exclusive exploration rights to countries and companies around the world.
1. China has a total of five exclusive exploration rights, more than any other country.
2. Two of these are around Minamitorishima, where China obtained exploration rights for cobalt-rich crusts in 2014 and manganese nodules in 2019.
Nippon Foundation’s analysis results:
The Nippon Foundation requested an Australian company to “analyze Japan’s EEZ offshore Minamitorishima.”
As a result, the total resource volume of the deposits offshore Minamitorishima was 620,000 tons of cobalt and 660,000 tons of nickel.
1. The density of manganese nodules offshore Torishima is twice that of the CCZ offshore Hawaii.
2. Ocean currents from the Antarctic converge offshore Minamitorishima due to the influence of the undersea topography.
The cobalt concentration in the nodules is comparable to that of mines in the Democratic Republic of the Congo, the world’s number one producer of cobalt.
Comparison with the CCZ offshore Hawaii:
Offshore Hawaii also contains important minerals in an amount close to the world’s total land reserves.
1. The density of manganese nodules in Minamitorishima is twice that of the CCZ.
2. The concentration of cobalt nodules in Minamitorishima is 1.6 times higher.
3. The nickel concentration in Minamitorishima was three times that of the CCZ.
https://www.yomiuri.co.jp/science/20241129-OYT8T50091/
University of Tokyo: Develops a seafloor rare metal exploration system
Summary from an article published in Drone-journal.
University of Tokyo Institute of Industrial Science:
A joint research project between the University of Tokyo and Worldscan has been launched.
1. A system for acquiring and analyzing deep-sea rare metal resource information has been jointly developed.
2. In 2023, metal detection and magnetic data were successfully acquired in a 1,700m deep-sea exploration.
Deep-sea rare metal and resource information analysis system:
A detailed investigation of “magnetic responses on the seafloor” will be conducted using a tethered remotely operated robot ROV and sensors.
1. Worldscan develops a new magnetic sensor (metal detection sensor).
2. The Thornton Laboratory at the University of Tokyo Institute of Industrial Science has developed a 3D image mapping system.
Seafloor magnetic survey using ROV in 2023:
1. 1. The new magnetic sensor “JIKAI” detects magnetism on the seafloor and investigates magnetic anomalies in detail.
2. The 3D map “SeaXerocks3” measures high-precision latitude and longitude, bottom sediment, and microtopography of the ocean floor.
It grasps the amount and location of rare metals in the deep sea and creates an accurate seafloor resource map.
Use in offshore wind power facility and inspection system:
Underwater cables that transmit energy generated at offshore wind power facilities.
1. With conventional metal detection sensors, it is difficult to accurately measure the magnetic field of underwater cables.
2. In the future, “JIKAI” will be miniaturized so that it is not affected by strong magnetic field environments.
“JIKAI” will be installed on an autonomous underwater robot (AUV) to efficiently inspect offshore wind power facilities.