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JOGMEC successfully identifies Mineral Resource Potential at 50-million-ton level through resource assessment of seafloor hydrothermal deposits- Steady progress towards development of seafloor hydrothermal deposits in EEZ zone -
JOGMEC successfully identifies Mineral Resource Potential at 50-million-ton level through resource assessment of seafloor hydrothermal deposits
- Steady progress towards development of seafloor hydrothermal deposits in EEZ zone -
PDF version of this page (168 KB)November 8, 2023
Japan Organization for Metals and Energy Security (JOGMEC) has continuously conducted reconnaissance exploration, drilling, and mineral resource assessment of seafloor hydrothermal deposits, mainly contains copper, zinc, lead, gold, and silver (Note 1), in the Okinawa and Izu-Ogasawara marine regions.
Based on the results of the surveys to date, mineral resource assessments have been conducted for the “Hakurei site,” “Gondou site,” “Dana site,” “Noho site,” “Amami site” and “Ginsui site” in the Okinawa marine region, as well as the “Hakurei prospect” in the Izu-Ogasawara marine region. The total estimated Mineral Resource Potential (Note 2) was 51.805 million tons in these assessments. This achievement is an important milestone that provides the basis for formulating future development of seafloor hydrothermal deposits in the EEZ.
In the future, JOGMEC will continue to conduct exploration to improve the confidence of resource estimates at existing sites, evaluate the resource potential at unexplored sites, and discover new deposits. JOGMEC is determined to further our efforts to contribute to government initiatives.
Based on the results of the surveys to date, mineral resource assessments have been conducted for the “Hakurei site,” “Gondou site,” “Dana site,” “Noho site,” “Amami site” and “Ginsui site” in the Okinawa marine region, as well as the “Hakurei prospect” in the Izu-Ogasawara marine region. The total estimated Mineral Resource Potential (Note 2) was 51.805 million tons in these assessments. This achievement is an important milestone that provides the basis for formulating future development of seafloor hydrothermal deposits in the EEZ.
In the future, JOGMEC will continue to conduct exploration to improve the confidence of resource estimates at existing sites, evaluate the resource potential at unexplored sites, and discover new deposits. JOGMEC is determined to further our efforts to contribute to government initiatives.
Image of seafloor hydrothermal deposits
Note 1: Seafloor hydrothermal deposits
Seafloor hydrothermal deposits are formed by the precipitation of metallic elements such as copper and zinc contained in hydrothermal water rising from the seafloor surface and cooled by seawater. In Japan, they are distributed in the Okinawa region, Izu-Ogasawara region, and their occurrence has been confirmed at depths of 500m to 3,000m.
Note 2: “Mineral Resource Potential”
The concept of Mineral Resource Potential, a unique concept pioneered by JOGMEC in the exploration of seafloor hydrothermal deposits, is roughly equivalent to the combined value of the Inferred Mineral Resources and the Exploration Results as defined by the international standard for onshore resource evaluation. The calculation of the Mineral Resource Potential used a calculation method employed in the mining industry to determine the Inferred Mineral Resources for onshore mineral deposits. In addition to the calculation method above, this approach also incorporates the calculation for potential and expected ore body projected from specific geological attributes of each survey area (site), drilling results, metal grades obtained by extrapolation and simplified analysis, insights from previous research and studies on deposits formation processes, and results from seafloor observations and geophysical exploration. The procedures and results of the calculations, including the given conditions, have been advised by external experts.
Seafloor hydrothermal deposits are formed by the precipitation of metallic elements such as copper and zinc contained in hydrothermal water rising from the seafloor surface and cooled by seawater. In Japan, they are distributed in the Okinawa region, Izu-Ogasawara region, and their occurrence has been confirmed at depths of 500m to 3,000m.
Note 2: “Mineral Resource Potential”
The concept of Mineral Resource Potential, a unique concept pioneered by JOGMEC in the exploration of seafloor hydrothermal deposits, is roughly equivalent to the combined value of the Inferred Mineral Resources and the Exploration Results as defined by the international standard for onshore resource evaluation. The calculation of the Mineral Resource Potential used a calculation method employed in the mining industry to determine the Inferred Mineral Resources for onshore mineral deposits. In addition to the calculation method above, this approach also incorporates the calculation for potential and expected ore body projected from specific geological attributes of each survey area (site), drilling results, metal grades obtained by extrapolation and simplified analysis, insights from previous research and studies on deposits formation processes, and results from seafloor observations and geophysical exploration. The procedures and results of the calculations, including the given conditions, have been advised by external experts.
Background on the Mineral Resource Potential of 50 million tons
The resources of seafloor hydrothermal deposits were determined as 3.4 million tons in the First Basic Plan on Ocean Policy (FY 2008-2012) and 7.5 million tons in the Second Basic Plan on Ocean Policy (FY 2013-2017). The most emphasized task outlined in the "Third Basic Plan on Ocean Policy (FY 2018-2022)" was resource identification at the level of 50 million tons. In addition, the Plan for the Development of Marine Energy and Mineral Resources, which was revised after the formulation of the above-mentioned plan, set a target of confirming an approximate resource level of 50 million tons and ordered to work on toward this goal. The 50-million-ton level is a rough estimate of resources that have a metal value of 2 trillion yen and can be extracted over 15 years or more.
Measures to achieve Mineral Resource Potential of 50 million tons
It was thought that it would be extremely difficult to identify the Mineral Resource Potential of 50 million tons in the third plan, given that the figures for the first and second plans were 3.4 million tons and 7.5 million tons, respectively. However, this achievement was realized through proactive drilling and reconnaissance explorations conducted by JOGMEC’s research vessel, Hakurei, in conjunction with private-sector research vessels. Until the second plan, exploration was carried out exclusively by “Hakurei”. The expansion of the scope of the drilling was made possible by the inclusion of private-sector research vessels in the third plan. The “Amami site,” which was discovered during the reconnaissance exploration in the third plan, also contributed to the attainment of Mineral Resource Potential. It is necessary to improve the confidence of the Mineral Resource Potential of this calculation by additional drilling and resources assessment towards commercialization of seafloor hydrothermal deposits, and we will proceed with our efforts.
Reference
The inquiry about this page.
Seafloor Mineral Resources Department
Tel +81-3-6758-8030
Public Relations Division
Tel +81-3-6758-8106
